Conference Program at a Glance

Nassau Gramercy East Gramercy West
 MONDAY, AUGUST 21, 2023
 7:00 am REGISTRATION (Second Floor South Corridor)
 8:00 – 9:00 am CHAIRMAN’S ADDRESS
Strategies for Bridge Maintenance
Khaled Mahmoud, PhD, PE
Chief Bridge Engineer, BTC, New York City, USA

KEYNOTE SESSION I
Maintenance Strategy for New York City Bridges
Paul Schwartz, PE
Deputy Commissioner/Chief Bridge Officer
Division of Bridges New York City Department of Transportation, USA
 9:05 – 9:40 am COFFEE BREAK (Murray Hill & Second Floor South Corridor)
9:45 am – 12:05 pm SESSION 1A: BRIDGE DESIGN (I) SESSION 1B: BRIDGE MANAGEMENT & DIGITAL DESIGN SESSION 1C: STEEL BRIDGES
 12:10 – 1:15 pm LUNCH (Murray Hill & Second Floor Corridor)
 1:30 – 3:30 pm SESSION 2A: EVALUATION AND STRENGTHENING OF BRIDGES SESSION 2B: BRIDGE INSPECTION, REHABILITATION AND REPLACEMENT SESSION 2C: BRIDGE CABLE EVALUATION AND AERODYNAMICS (I)
 3:35 – 4:10 pm COFFEE BREAK (Murray Hill & Second Floor South Corridor)
 4:15 – 6:15 pm SESSION 3A: SEISMIC ANALYSIS & RETROFIT SESSION 3B: BRIDGE COATING, CATHODIC PROTECTION & REPAIR SESSION 3C: MAINTENANCE OF LONG-SPAN BRIDGES
Room A Room B Room C
TUESDAY, AUGUST 22, 2023
7:00 am REGISTRATION (Second Floor South Corridor)
8:00 – 8:40 am CHAIRMAN’S INTERIM ADDRESS

KEYNOTE SESSION II
Risk-Based Analysis of Sensors on Two Cable-Stayed Bridges in China & UK
Professor Micheal C. Forde
School of Engineering, The University of Edinburgh, Scotland, UK
8:45 – 9:20 am COFFEE BREAK (Murray Hill & Second Floor South Corridor)
9:25 – 11:25 am SESSION 4A: MAINTENANCE OF CONCRETE BRIDGES SESSION 4B: RAILWAY BRIDGES SESSION 4C: CABLE SUPPORTED BRIDGES (I)
11:30 pm – 12:40 pm LUNCH (Murray Hill & Second Floor South Corridor)
12:50 – 2:50 pm SESSION 5A: ASSESSMENT & RECONSTRUCTION OF BRIDGE DECK SESSION 5B: RELIABILITY-BASED ANALYSIS AND EVALUATION SESSION 5C: BRIDGE CABLE EVALUATION & AERODYNAMICS (II)
2:55 – 3:30 pm COFFEE BREAK (Murray Hill & Second Floor South Corridor)
3:35 – 5:55 pm SESSION 6A: BRIDGE INSTRUMENTATION & MONITORING SESSION 6B: BRIDGE DESIGN (II) SESSION 6C: CABLE-SUPPORTED BRIDGES (II)
6:00 – 6:15 pm CHAIRMAN’S CLOSING REMARKS

KEYNOTE SESSIONS

Gramercy Room

MAINTENANCE STRATEGY FOR NEW YORK CITY BRIDGES

Paul Schwartz, PE
Deputy Commissioner/Chief Bridge Officer
Division of Bridges
New York City Department of Transportation, New York, USA

RISK BASED ANALYSIS OF SENSORS ON TWO CABLE STAYED BRIDGES IN CHINA AND UK

Professor Micheal C. Forde
School of Engineering
The University of Edinburgh
Scotland, UK

TECHNICAL SESSIONS

ASSESSMENT & RECONSTRUCTION OF BRIDGE DECK
BRIDGE INSPECTION, REHABILITATION AND REPLACEMENTMAINTENANCE OF CONCRETE BRIDGES
BRIDGE CABLE EVALUATION & AERODYNAMICS (I)BRIDGE INSTRUMENTATION & MONITORINGMAINTENANCE OF LONG-SPAN BRIDGES
BRIDGE CABLE EVALUATION AND AERODYNAMICS (II)BRIDGE MANAGEMENT & DIGITAL DESIGNRAILWAY BRIDGES
BRIDGE COATING, CATHODIC PROTECTION & REPAIRCABLE SUPPORTED BRIDGES (I)RELIABILITY-BASED ANALYSIS AND EVALUATION
BRIDGE DESIGN (I)CABLE-SUPPORTED BRIDGES (II)SEISMIC ANALYSIS & RETROFIT
BRIDGE DESIGN (II)EVALUATION AND STRENGTHENING OF BRIDGESSTEEL BRIDGES

SESSION 1A: BRIDGE DESIGN (I)

MONDAY, AUGUST 21 ● 09:45 am – 12:05 pm ● Nassau
Session Chair: Jeffrey Wright, PE, Chief Engineer, New York State Bridge Authority, New York, USA

ABSTRACT: Over time, owners may face challenges with management of bridges with outdated details. One such detail that is no longer used today is the steel girder shiplap connection. These were originally employed to simplify analysis of continuous girders while also moving
joints away from the piers, improving longevity of bridge bearings and substructures. Unfortunately, fatigue issues have appeared in these connections resulting in cracking at critical loadcarrying locations. In this project, analysis was performed to investigate connection fatigue and strength and retrofit design verification. Results utilizing non-linear analysis showed that while stresses from ultimate loading could adequately redistribute throughout the web, high stress concentrations were created, exacerbating fatigue. Stress calculations for shiplap web details are not well codified or easily assessed with simple hand calculations, so finite element analysis was utilized. Results showed web fatigue life had been exhausted with more cracking expected at other locations, convincing the owner retrofit was necessary even though the bridge was programmed for replacement.

ABSTRACT: Arup is the Engineer of Record for the Park Union Bridge, opened to pedestrians in July 2021, connecting the U.S. Olympic & Paralympic Museum to America the Beautiful Park and Downtown Colorado Springs. Called the rip curl for its cresting design, the footbridge spans 245ft over active rail lines. The 300 ton steel superstructure is designed to both integrate with the aesthetic vision for the museum and to minimize impact on rail operations during construction. One of the key project successes for the design team was producing a design that struck a balance between achieving the aesthetic vision and minimizing the impact on the rail-roads below. From bridge inception, the designers leveraged their parametric 3-D work environment to communicate visually and explain crucial aspects of the bridge behavior among themselves and with key collaborators of the project team.

ABSTRACT: North American bridge codes have either transitioned or are in the process of transitioning from a load factor-based wind design approach to an ultimate wind speed de-sign approach. This transition was meant to unify risks across different wind climates in a way that load factors could not easily accomplish. Moving to the ultimate level wind speed leads to the potential of increased aeroelastic effects including coupling of degrees-of-freedom as well as changes to the structure based on aerodynamic damping and stiffness. These coupling, damping and stiffness effects do not typically follow the square of the wind speed rule and are the focus of the current study. The aeroelastic effects are also assessed in the current study through the use of the stack state-space buffeting approach demonstrated on two test cases. The results of these studies are incorporated into a Monte Carlo approach to evaluate the risk of failure in a simplified reliability analysis in four different wind climates typical of different regions across North America. Based on these studies it is shown that the move to ultimate level wind speeds helps to unify the risk of failure across wind climates and due to a wide-ranging aeroelastic effects.

ABSTRACT: This paper describes the role of Independent Engineer (IE) in the design and construction of the newly constructed New Bridge over the Saint Lauren (NBSL) also known as the New Champlain Bridge in Canada. Designed in 1962 and used by millions of commuters each year, the Champlain Bridge, which connects Montreal and the South Shore, had reached the end of its service life, and needed to be replaced. The new $3.2B Private Public Partnership (P3) project includes a 2.1 mile long New Bridge with a 790-foot cable stay main span. It also includes 19 bridge overpasses, and more than 3 miles of highway improvements. The new Bridge has two three-lane corridors for vehicular traffic and a two-lane light rail transit system. The new Bridge also includes a multi-use path for pedestrians and cyclists. This new bridge has a 125-year design life and was open to highway traffic in both directions on July 1, 2019. The construction is ongoing on the bridge to install the light rail transit system which is expected to open in the Spring of 2023. Various monitoring mechanisms have been set out to ensure that the Private Partner delivers the project in compliance with stipulated performance criteria. The Stantec and Ramboll team was selected by Private Partner and the Government of Canada to be the Independent Engineer, whose mandate involves: • Examining, at various stages, the design documents, supervision plans and the management and quality control system provided by the Private Partner (PP) • Performing design reviews at various stages of the design • Monitoring all work for the purpose of compliance with the Project Agreement (PA) • The certification of the completion of the work at substantial and final completion stages In summary, the IE role includes performing independent reviews, quality reviews, site and shop inspections, quality audits, and completion certifications.

ABSTRACT: Composite repair has been proven to be an efficient technique for repairing fatigue-damaged structures. However, the efficiency of this repair technique highly depends on understanding the mechanics behind how composite patching improves fatigue life. Laboratory scale experimentation and numerical simulations were conducted to better understand the behavior and to determine what controls the efficiency of composite repair for fatigue-damaged structures. It was found that besides selecting the correct composite materials for patching, the adhesive bonding between the patch and substrate is extremely important. In this experimentation, fatigue life was extended by more than 500% by designing an efficient composite patch and adhesive bond line for the damage. Finite element analyses were conducted to support and refine the design of the repair techniques.

SESSION 1B: BRIDGE MANAGEMENT & DIGITAL DESIGN

MONDAY, AUGUST 21 ● 09:45 am – 12:05 pm ● Gramercy East
Session Chair: Michael C. Forde, Professor, School of Engineering, The University of Edinburgh, Scotland, UK

NYCDOT’s Structural assessment of the Triple Cantilever section of the BQE included both NDT and nonNDT testing. Review of the design live load, versus legal loads and potential overweight loading in relation to remaining service life prediction led to the installation of WIM sensors in 2019. The information gathered led to refinement of service life analysis as well as the push for first-in-nation direct enforcement of truck weight limits. Beyond the legislative approval, the need for national calibration and acceptance efforts was also pursued for the implementation of the program.

ABSTRACT: Departments of Transportation (DOTs) and/or local road agencies collect vehicle permits and weigh-in-motion (WIM) data. Rarely, these two unique data set sources are fused or used together for a full understanding of route-specific freight trips. However, there are challenges in using these data sets together. There is a need to present specific data issues and approaches using the data to improve our knowledge of the freight network and roadway loading. The objectives of this paper are to share information on both permitted vehicles and WIM data and how they can be used to address highway infrastructure needs. The traffic flow includes regular freight travel along with permit vehicles and illegally loaded vehicles. There is a need for procedures to identify permit vehicles in the traffic flow. A large volume of data from these two sources (permit and WIM data) exists, and improved procedures are needed for processing this big data set between these data sources. This involves the development of efficient filtering procedures to eliminate or tag questionable data. Another objective is the fusion of the permitted overloaded vehicles vs. those considered overloaded based on the WIM data results. Knowledge of truly overloaded vehicles is needed. Fusion of the permit and WIM data helps in assessing the number of overloaded vehicles vs. legally permitted vehicles that have State approval to travel along specific roadways.

ABSTRACT: In world practice, as a rule, developed countries use modern information systems such as Bridge Management System to make effective management decisions on the operation of bridges. In Ukraine, such a system began to be created in 2004, it is called Analytical expert bridge management system (AESUM). In 2006, the process of its implementation in the management system of the Road Authority began, the function of which included the management of the operation of bridges on public roads. The implementation of the AESUM system led to the fact that it is possible to quickly get answers to many questions regarding detailed information on bridges, to analyze the aggregate of bridges in terms of certain parameters, to build schedules of bridge inspections, to predict the degradation of bridge elements, and accordingly, to predict with a certain probability the technical condition of bridges, calculate estimated repair costs and build certain strategies for bridge operation both in the long term and in the short term. The information collected in such systems is obtained on the basis of inspections conducted on bridges. A bridge inspection is an important part of bridge life cycle, its results make it possible to plan the effective use of funds for bridge maintenance and therefore considerable attention should be given to this type of work. A timely bridge inspection makes it possible to ensure reliable and trouble-free bridge maintenance. The best practices show that the cost of the bridge inspection is repaid by optimizing the cost of bridge maintenance. Only in the case of a comprehensive timely assessment of the bridge state and timely implementation of repair works, effective bridge maintenance is possible. 

In February 2022 russia’s brutal and unprovoked full-scale war against Ukraine began. Bridges in such a situation play a strategic role, sometimes even a key one. Many bridges were damaged and destroyed on the territory of Ukraine. In such difficult conditions, work on the restoration of bridges is carried out. At present, significant areas of Ukraine are still in uncontrolled territory. I believe this situation will be change soon and the challenge will be to restore the country in a short time, and with it a large number of bridges. The help of the international community is needed in this process. 

Keywords: bridge, bridge inspection, technical state, software, AESUM, war. 

ABSTRACT: Located in Delaware, Taylors Bridge Road Bridge carries vehicular traffic for State Route 9 (SR-9) over Blackbird Creek. The existing bridge is a 10 span, simply sup-ported, non-composite prestressed concrete box girder bridge built in 1964. Delaware Department of Transportation (DelDOT) determined that replacement offered better value than continued maintenance/retrofit. Pennoni Associates, Inc (Pennoni) provided design services for the structure. As part of its evaluation of digital delivery and BIM technologies, DelDOT requested that Pennoni deliver preliminary and detailed design through a model-based process using Nemetschek Group’s Allplan software. Pennoni was tasked with creating both digital and traditional deliverables. This paper addresses the methodology and rationale behind these design choices and discusses experiences in delivering a project in both digital and CAD formats. The authors present a foundation for further exploration of BIM model-authoring and model-consumption tools, important software toolsets, and rectification of shortcomings in tools and practice.

ABSTRACT: This paper aims to demonstrate how the utilization of OpenBrIM Platform’s cloud-based parametric workflows can lead to significant time and cost savings in 3D/FEA modeling and design code checks. The objective of this study is to showcase the benefits of OpenBrIM technology through a rehabilitation project in Florida State. It focuses on highlighting the improved competencies required to build a parametric 3D/FEM model for complex staged deconstruction/reconstruction bridge analysis on the cloud using the OpenBrIM Platform.

ABSTRACT: Little Island on the Hudson River is a newly opened 10,000m2 public park that features a unique, sculptural shape with irregular, undulating, and complex curved ge-ometry that conventional design, documentation, and construction methods could not de-liver. The design team adopted the latest technologies in digital parametric scripts to gener-ate almost all structural elements. The workflow was streamlined from the architectural concept through to the construction information which was represented in 3D electronic models rather than the conventional 2D drawings. In the fabrication phase, CAD/CAM subtractive techniques with CNC milling were utilized to create complex curved precast concrete elements and individually defined steel connection elements. Assembly of the structural module was done off-site to ensure the quality and speed to meet the schedule. This paper illustrates the details of the innovative approaches and implementations made by the design and the contracting team to realize a large-scale iconic project in New York City with complex geometries.

SESSION 1C: STEEL BRIDGES

MONDAY, AUGUST 21 ● 09:45 am – 12:05 pm ● Gramercy West
Session Chair: Jamie F. Farris, PE, Bridge Division Deputy, Director, Texas Department of Transportation, USA

ABSTRACT: Using three I-girders to make a bent cap offers significant advantages compared to traditional box-style caps. The primary advantage is that three I-girder caps have redundancy and are therefore not fracture critical members (or non-redundant steel tension members). This distinction precludes the need for costly and intrusive in-service fracture critical inspections over the life of the structures. Another advantage is that three I-girder caps require significantly less effort to fabricate compared to traditional box-style caps, and these savings result in lower fabrication cost and improved fabrication schedule for these elements.

ABSTRACT: Cross-frames and diaphragms are important steel bridge components as they provide stability to primary longitudinal girders and improve lateral or torsional stiffness and strength of the bridge system during construction and in-service. Over the last few years, the steel bridge industry has seen a general increase in the size of cross-frames used in steel I-girder bridges across the country, in terms of both the individual member sizes and the connections themselves, resulting in significant inefficiencies, especially in skewed and curved girder bridges. On a cost per pound basis, the cost to fabricate cross-frames can be the most expensive part of any steel girder bridge project. This presentation will review the design history of cross-frames, and then provide guidance to designers based on the complexity of their bridge, so that they can make better choices regarding cross-frame and diaphragm layouts and types, members, connections as well as loads, analysis, and design. Fabrication techniques for cross-frames and diaphragms will also be discussed, explaining why certain decisions will result in more efficient fabrication of cross-frames and diaphragms.

ABSTRACT: Inorganic zinc (IOZ) coatings are frequently used as a primer layer in paint systems for steel structures. However, these coatings can also be used by themselves and provide an economical and durable corrosion protection. This application of inorganic zinc coatings is referred to as single-coat inorganic zinc (SIOZ) and was the subject of a recent literature review, field assessment and owner survey by NSBA. This presentation will provide an overview of that work and next steps.

ABSTRACT: The advent of new AASHTO guidance on Internal redundancy offer the designer new opportunities for innovation for extending the life of existing bridges and to develop new structural systems with enhanced safety and reduced maintenance costs. This presentation explores two use cases for internal redundancy: i) rehabilitation of the upper level anchorage spans at the Verrazzano Narrows Bridge (VNB), and ii) the replacement of two short span bridges for Indiana DOT using press brake bent plate tub girders. Taking maximal advantage of Internal redundancy was key in both of these projects, but the strategies were entirely different. For the rehabilitation of the anchorage spans at VNB, staged construction required a number of unusual choices, which ultimately led to stacked floorbeams drilled in assembly on site. As this is a two level structure, with replacement of the upper level deck and structural steel, lower level night-time closures were necessary for this operation. Field drilling was performed efficiently and was useful in accommodating geometry deviations that inviariably arise in rehab projects that require staged construction. The Indiana DOT projects limit the press brake component to the webs, which are bent in a z shape. Internal redundancy is achieved via the use of bolted top and bottom flanges. This strategy promises to extend the span range of press brake tub girders substantially as the webs can be much deeper, and the change in flange sizes gives the designer the ability to customize the cross section. The webs for these bridges were produced using pole manufacturing work flows and steels used in this industry which are typically 65 ksi yield strength. These bridges were evaluated for both the complete fracture of an entire web or the entire bottom flange, with very little impact to overall load carrying capability

ABSTRACT: Two AASHTO Guide Specifications were released at the end of 2018 with 2022 interims. They offer the analytical framework needed to revisit the way we evaluate redundancy in steel bridges considering system-level and member-level redundancy for new or existing bridges. For the last four decades, the steel bridge industry has become accustomed to determining redundancy through engineering judgment married to a single approach, namely load path redundancy (referring to the number of girder lines). Publication of the 2022 NBIS has opened up design to other modes of redundancy and with it, new inspection protocols. Combined with the new AASHTO Guide Specifications, industry experts are now enabled to design outside the box that we put ourselves in 40 years ago. This presentation will briefly explore how owners and designers can take advantage of risk-based inspection intervals that are intrinsically linked to the redundancy of their steel bridge designs.

SESSION 2A: EVALUATION AND STRENGTHENING OF BRIDGES

MONDAY, AUGUST 21 ● 1:30 – 3:30 pm ● Nassau
Session Chair: Luke Tarasuik, PE, CPEng, Associate, Americas Bridge and Civil Structures Skills Leader, Arup, USA

ABSTRACT: Nondestructive evaluation (NDE) and structural monitoring are both essential tools for assessing the condition of structures, but they serve different purposes. NDE is typically used for localized investigations and provides a snapshot of the test section condition at the time of testing. It can identify specific areas of concern or verify that a repair has been successful. NDE methods can include techniques such as ultrasonic tomography, GPR, and impact echo, among others. On the other hand, structural monitoring provides information about the global condition of a structure over a long period. It can detect changes in a structure’s behavior, such as deformation or cracking, and monitor the effects of environmental factors such as temperature and moisture. Structural monitoring methods can include strain gauges, accelerometers, and vibration sensors. While NDE and structural monitoring serve different purposes, they can also overlap in certain situations. For example, NDE methods may be used to verify the results of structural monitoring, or structural monitoring data may be used to guide the selection of areas for NDE investigations. This presentation is an overview of the general discussion of the differences between NDE and structural monitoring and how they can be used together to assess the condition of structures.

ABSTRACT: Over the coming years, bridges and other physical infrastructure will experience unprecedented demands due to extreme weather and trends in freight. These increasing demands are set against a backdrop of infrastructure deterioration as many assets reach the end of their intended service life. Bridge owners have done a significant amount of work to identify vulnerabilities in their infrastructure but challenges such as budget constraints and environmental complexities limit their ability to adapt.
The proper application of technology, however, can help bridge owners safely extend the useful life of their structures. This can be done by gathering information that can be used to optimize lifecycle costs, to better quantify vulnerabilities, and maintain situational awareness to mitigate risk. This is particularly important for long-span bridges which require a disproportionate amount of maintenance expenditures and would cost billions of dollars to replace. However, there are still multiple challenges to deploying a cost-effective structural monitoring system that provides easily understandable and actionable information. This paper will provide an overview of the current practice of managing long-span bridges using structural monitoring (SM), examining both new and existing bridges. The paper will draw on the authors’ combined experience working with numerous bridges, each with more than one hundred sensors. The need for new and improved resources for handling the large amounts of data generated by these systems will then be discussed. Finally, a vision for the future of SM for long-span bridges will be presented.

ABSTRACT: Back in April of 2021, bids were submitted to the New Jersey Department of Transportation for Contract 8B for the rehabilitation of the Pulaski Skyway. Skanska was the successful bidder at $161.5 Million. The project designed by GPI and URS (AECOM) involved the rehab of the superstructure and several piers on this three mile long viaduct that included 118 High load multirotational disk bearings with some unusual details to accommodate the 1000 year return earthquake loads and displacements. This paper will discuss the design, manufacture, testing and installation of these devices focusing on the unique details of the bearings that will provide many years of life for this iconic structure.

ABSTRACT: The application of Fiber Reinforced Polymer (FRP) materials in concrete structures has been rising due to their several advantages, including lightweight, high tensile strength, ease of installation, and corrosion resistance. They have been mostly implemented for strengthening and repairing existing structures in the form of an externally bonded system, i.e., sheet, jacket, near surface mounted. Furthermore, they have been recently utilized as internal reinforcement of concrete elements in the form of strands, bars, tendons, etc. Although higher durability and per-formance are associated with the FRP material in some aspects compared to steel, concerns re-main regarding damages and defects in this material, many of which are related to their unique features. Importantly, debonding of FRP materials from a concrete surface or within a concrete element has always been an issue resulting in the premature failure of the structure. To this end, concrete elements strengthened or reinforced with FRP materials has to be inspected periodically to detect potential issues and hence prevent any premature failures. This study first determines all possible or potential damages and anomalies attributed to FRP reinforced/strengthened concrete (FRP-RSC) elements. It then investigates Non-Destructive Testing (NDT) methods that can be applicable to the inspection of FRP-RSC elements from a literature survey of past studies, appli-cations, and research projects. Furthermore, this study evaluates the ability of two of the most commonly used NDT methods, Ground Penetrating Radar (GPR) and Phased Array Ultrasonic (PAU), in detecting FRP bars/strands embedded in concrete elements. GPR and PAU tests were performed on two slab specimens reinforced with GFRP (Glass-FRP) bars, the most commonly used FRP bar, with variations in their depth, size and configuration, and a slab specimen with different types of available FRP reinforcements. The results of this study propose the most appli-cable methods for detecting FRP and their damage/defects in FRP-RSC elements. By providing the inspection community with more clarity in the application of NDT to FRP, this study offers means for verifying the performance and, therefore, help the proliferation of FRP materials in concrete structures.

ABSTRACT: The Benjamin Franklin Bridge (BFB) is a heavily traveled bridge with a total Average Daily Traffic (ADT) of vehicles more than 100,000 and about 200 PATCO trains per day. After being in service for over ninety years, many major components in the sus-pended spans require replacement or strengthening, which includes the removal and re-placement of one hundred and eight (108) end sections of bottom lateral bracing in the suspended spans; four (4) wind pins at both towers; eight (8) rocker links at both towers; two (2) wind pins, four (4) end laterals and four (4) rocker links at both anchorages. To replace these elements, robust jacking frames and temporary supports were needed for supporting all vertical and lateral loads while causing minimal impacts to the traffic. They also need to be easy to construct and adjust. Many innovative designs were developed to achieve the project goals and keep the traffic smooth and safe.

SESSION 2B: BRIDGE INSPECTION, REHABILITATION AND REPLACEMENT

MONDAY, AUGUST 21 ● 1:30 – 3:30 pm ● Gramercy East
Session Chair: Michael Mangione, PE, Senior Vice President, HNTB, New York City, USA

ABSTRACT: The Longfellow Bridge is a historic structure and a recognizable landmark that crosses the Charles River between Boston and Cambridge in Massachusetts. The “Salt and Pepper Bridge”, nicknamed so due to prominent granite towers flanking its center span, was originally constructed in 1907 and has recently undergone a rehabilitation through a $305 million Design-Build Contract. In fact, the bridge history claims that it is the first bridge in the United States intentionally designed to carry rail and vehicular traffic raising its already historic profile. The functional capacity of the bridge, which carries pe-destrian, roadway, and light rail traffic, was restored along with the historic bridge aesthet-ic. Original steel arches and granite piers remained in place, with repairs and retrofits in-stalled as needed. Additional members, including built-up steel spandrel columns, string-ers, and floorbeams, were manufactured to replicate the original design of the bridge while carrying modern loads, including current seismic criteria. The historic fabric was main-tained even to the point where approximately 10,000 structural rivets were used for the project and new buckle-plate decking forms replaced original ones. Staged construction, which included the use of a shoo-fly to move trains onto the roadway, allowed the bridge to remain open to traffic throughout construction.

ABSTRACT: The Williamsburg Bridge crosses the East River, connecting Manhattan and Brooklyn and carries approximately 111,000 vehicles, 92,000 transit riders, 600 bikers, and 500 pedestrians on a daily basis. Originally completed in 1903 and most recently rehabbed through the 1990s and early 2000s, it is time for another refresh. R.J. Watson has been selected by Skanska USA to supply disc bearings to replace the failed pot bearings that were installed during the late 1990s. 108 R.J. Watson Disktron Bearings will be engineered, manufactured, and installed on the structure’s approach spans. These bearings will range in vertical service load capacities between 155 kips and 400 kips, with a horizontal capacity ranging from 10% to 60% that of the vertical loads. Expansion bearings will allow for up to 15” of total movement and all bearings will accommodate a rotation of up to 0.025 radians. The intriguing aspect of these bearing is how they will be designed to fit within the limited space available: custom engineered to reduce bearing heights and to fit on existing pier caps. The bearings will also need to be delivered in a configuration that is easily movable by the contractor, as installation is not as simple as picking the bearing up and setting it down on a pier without any obstruction. This presentation will cover the history of the bridge bearing, the evolution to the disc bearing, typical applications of a disc bearing, and the Williamsburg Bridge case study example.

ABSTRACT: The Easterly Passaic River Bridge, which opened in January 1952, carries the New Jersey Turnpike’s Eastern Alignment over the Passaic River. The bridge carries more than 110,000 vehicles per day and is the second largest structure in the New Jersey Turnpike Authority’s (the Authority) inventory. The original structure consisted of a riveted two-girder system, and was widened in 1971 with the addition of two welded steel plate girders. The structure has eight major pin and hanger assemblies in the girders connecting the three-span continuous main river unit to its adjacent spans.
Shortly after the bridge’s last major rehabilitation in 2008, the pin and hanger assemblies stopped functioning and the adjacent bearings began exhibiting excessive movements. HNTB designed repairs to address the sudden change in the structure’s behavior, which included replacing the pin and hanger assemblies and installing bearing restrainers. Work required specialized instrumentation, analyses, and complex vertical and lateral jacking systems. The contract was awarded to Cornell & Company, Inc. (Cornell) of Westville, NJ in February 2019, and it was completed in early 2022.
In July 2020, Cornell discovered that the girders at three of the eight pin and hanger locations were significantly offset and rotated relative to one another beyond anticipated tolerances. This prompted a significant redesign effort, which included checking for local stresses due to the offsets, determining the long-term performance of the links, and revising details using already fabricated components.
HNTB developed a change of plan through multiple working sessions with the Authority, Cornell, and the construction manager, whose involvement allowed for an expedited design while ensuring constructability. This proactive method was also used to evaluate an alternative lateral jacking system proposed by Cornell. Throughout the contract, HNTB and the key stakeholders worked collaboratively to successfully address all unanticipated field conditions on this complex rehabilitation project.

ABSTRACT: The Delaware Department of Transportation is replacing a low-level, bobtail swing span bridge carrying SR36 over Cedar Creek. The 70-year-old bridge has significant deterioration and requires increasing maintenance and repair work to maintain safe and reliable bridge operations. A key objective for the bridge replacement project is to relocate the new support, balance, and drive systems for the movable span above the flood elevation to protect the equipment, reduce maintenance and improve the reliability. Additionally, to match the approach roadway profile without reducing the bridge’s hydraulic opening, a shallow superstructure depth was required. Both goals will be achieved with the new bridge. A Dutch-style bascule bridge utilizes hydraulic cylinders, an overhead counterweight and balance frame and orthotropic steel deck system. The design of the new bridge will incorporate features that address the durability and future maintenance needs as well as the project specific hydraulic conditions of this busy waterway.

ABSTRACT: National Bridge Inspection Standards (NBIS) mandate minimum guidelines for the inspection of all publicly owned highway bridges in the United States. NBIS are mandated by federal statute at 23 U.S.C. 144 and implemented under 23 CFR 650 subpart C. The primary goal of NBIS is to maintain bridge safety. Many owners do collect more data required than NBIS to assist with the bridge management decisions for planning future preservation and rehabilitation/replacement work. Recent updates to the NBIS have brought focus on using nondestructive and corrosion testing technologies to augment bridge in-spection and has introduced other data items that will promote bridge/asset management by the owners. These changes will bring more uniformity among states so that bridge inspec-tion data can also be useful for making bridge preservation and management decisions to maintain highway bridges in a cost-effective manner. This paper describes some of these efforts.

SESSION 2C: BRIDGE CABLE EVALUATION & AERODYNAMICS (I)

MONDAY, AUGUST 21 ● 1:30 – 3:30 pm ● Gramercy West
Session Chair: Paul Schwartz, PE, Deputy Commissioner, Chief Bridge Officer, NYC Department of Transportation, USA

ABSTRACT: This study investigated the relationship between “rust color distribution ratio,” “corrosion surface shape,” and “fatigue strength” of high-strength galvanized steel wires used in cable supported bridges. The study utilized a digital image color analysis system to classify the rust color distribution rate and categorize corrosion levels based on the distribution ratio. The relationship between cross-sectional loss rate and corrosion depth tendency was visually and quantitatively comprehended from the categorized corrosion levels. The study found that fatigue and tensile strengths of the specimens from the corrosion levels set in this study were equivalent to or higher than those of new wires. However, the possibility of variations due to the small number of specimens or insufficient corrosion progress cannot be ruled out.

ABSTRACT: Wind stability and design loads of long-span bridges are assessed applying experimental and theoretical methods. The commonly used approach entails the extraction of fundamental aerodynamic data of key structural elements such as the deck, towers, and cables, either experimentally or numerically, and the application of theoretical models for evaluation of structural responses to turbulent winds. This phenomenon called buffeting is extremely complex and, to date, there is no closed-form theoretical model to reproduce how the wind converts to structural responses and loads which the bridge must resist. The objective of this paper is to explore the base of the problem, namely the transformation of wind gusts to actual loads, and the response estimations. The time domain response approach has been adopted for solution of the generalized equations of motion allowing the exploration of details in the performance of various theoretical interpretations. Starting from the classic quasi-static linear model, theoretical simplifications are removed toward a more complete model of buffeting loads. Non-linear and aerodynamic coupling effects on response predictions are examined specifically aiming at improved buffeting load representations within the framework of the currently available experimental data. A new concept called stack state-space analysis has been introduced for the response solution to wind buffeting. Aerodynamic and structural data of Pierre-Laporte Bridge in Québec City, and the IABSE Working Group 10, long-span bridge validation example, are utilized as representative cases in this study. Avenues for further experimental and numerical validations of the presented new solution approach are suggested toward more accurate predictions of wind response and design loads of long-span bridges.

SESSION 3A: SEISMIC ANALYSIS & RETROFIT

MONDAY, AUGUST 21 ● 4:15 – 6:15 pm ● Nassau
Session Chair: Alp Caner, PhD, PE, Professor, METU & BridgeWiz, Turkey, WSP, USA

ABSTRACT: There are quite a few bridges designed by the old design codes in Japan. Many of those bridges may not be satisfactory for the current seismic design codes. The behavior of a steel truss bridge under a large seismic loading is checked out by the nonlin-ear dynamic finite element analysis in the present study, and indeed some members are found damaged in the earthquake. The buckling restrained bracing (BRB) is widely used to improve the seismic behavior of a building. On the other hand, the application to a bridge is very limited. The BRB device may also be used as a damper rather than the structural component, the bracing, in which case the device is called a buckling restrained damper (BRD). Yet, such application has not been explored much. In the present paper, the appli-cation of the BRD is tried. A parametric study on the seismic behavior of a steel truss bridge with BRDs is conducted by changing the length and the cross-sectional area of the yielding core of the BRD. The influence of the locations of BRDs is also considered. Fol-lowing the seismic design codes for highway bridges in Japan, the performance of the bridge with BRDs are investigated using three seismic loadings. The study concludes that with the application of well-designed BRDs to appropriate locations, a steel truss bridge could go through a large earthquake without damage

Abstract: A seismic design standard is presented that: lowers construction costs; avoids earthquake damage; and saves lives by enabling post-earthquake emergency services. Ecuador’s 2016 magnitude 7.8 earthquake fault ruptured directly under the Bahia Bridge. The 3g seismic force demands were 20 times the seismic design strengths required by AASHTO. The bridge has seismic isolators compliant with the Seismic Isolator Standard “SIS” [UCB]. These Triple Pendulum seismic isolators reduced the seismic design forces on the pile foundations by 80%, reducing construction costs by 5%, and avoiding earthquake damage. This was the first time a bridge remained 100% functional after experiencing such strong earthquake shaking. Over the past 34 years 18 essential structures with SIS isolators have retained 100% functionality after 7 major earthquakes. These 18 structures also cost less to build. Absorbing earthquake displacements in SIS isolators avoids earthquake damage and saves construction costs, as compared to accommodating seismic displacements through plastic hinges in the bridge piers.

ABSTRACT: The Seto-Ohashi Bridges are about 10 km long road-rail bridge group con-necting Honshu and Shikoku in Japan; which consist of three suspension bridges, two ca-ble-stayed bridges, one truss bridge and elevated bridges with truss and concrete girders at-tached to them. It had carried out the seismic retrofit for the Seto-Ohashi Bridges with the aim of limiting damage caused by major earthquakes and keeping the bridge in a state where its functions can be restored as soon as possible. The basic approach for the seis-mic retrofit was to reinforce only the members that exceeded their bearing capacity, after studying the measures to be taken for these bridges as a whole, in order to reinforce them reasonably because the Seto-Ohashi Bridges have a large number of components. As a re-sult, seismic retrofit of the Seto-Ohashi Bridges began in 2014 and was completed in 2021.

ABSTRACT: The bid price, final cost and delivery schedule of seismic isolation bearings are significantly impacted by the contract/bid documents. Often, critical information is missing, there are conflicting requirements, and unnecessary complexity result in manufacturers and contractors either adding cost to their initial pricing or relying on change orders to cover the added costs if the Owner ultimately has a more expensive interpretation of the manufacturer’s scope of work. The type of issues encountered are not generally possible to resolve during the bid phase using the bidder inquiry process. Resolution of the issues takes place after both contract award and issuance of a purchase order to a manufacturer, and often takes a considerable amount of time. Delivery of isolation bearings to the jobsite is ultimately delayed, sometimes having deleterious effect on the construction schedule.
This paper describes some of the problems commonly encountered and presents solutions that ensure the Owner’s intent and requirements are correctly communicated to the bidders while eliminating the cost and schedule impacts often experienced on bridge projects that incorporate seismic isolation bearings.

SESSION 3B: BRIDGE COATING, CATHODIC PROTECTION & REPAIR

MONDAY, AUGUST 21 ● 4:15 – 6:15 pm ● Gramercy East
Session Chair: Beatrice Hunt, PE, Principal Hydraulic Engineer, AECOM, New York City, USA

ABSTRACT: Halifax Harbour Bridges (HHB), a commission of the province of Nova Sco-tia, is responsible to operate and manage two long span suspension bridges, Angus L. Macdonald Bridge (1955) and A. Murray MacKay Bridge (1970), and their approaches. Long span cable supported bridges are complex and unique types of structures, bearing unique maintenance challenges. Corrosion protection of a massive steel structure in a harsh environment is one of the critical challenges. The bridges were originally painted with a lead-based oil alkyd three- coat paint system. Two independent coating consultants through detailed condition assessment recommended that the existing coating system should be re-placed for concerns of the integrity of the existing coating system and degree of rusting, full replacement of the existing coating system coupled with steel repair at unknown quan-tity is a significant capital investment. This paper discusses the issues, challenges, and op-portunities to develop and implement a suspension bridge corrosion protection program.

ABSTRACT: Bridge No. 02708 over Plum Creek in Old Saybrook Connecticut is a bridge on a main highway into the city. The Connecticut Department of Transportation decided that the bridge needed to be replaced in large part due to scour of the original abutment. A full accelerated bridge replacement was conducted at the beginning of 2021 and a steel cofferdam was installed around the new abutments. The sheet pile cofferdam was also designed to serve as scour protection. VCS Engineering was hired by Arborio Construction to design and install a cathodic protection system to protect the cofferdam from corrosion. Since the location of the bridge is close to the ocean and tidal, the environment is extremely susceptible to corrosion. VCS designed a galvanic anode system to protect the sheet piling using magnesium soil anodes. A horizontal anode string was designed to protect the interior and exterior of each cofferdam with all wires routed to four test stations so that each string of anodes can be monitored separately. The system was installed successfully and all checks on the bridge have shown that the system complies with NACE SP169 criteria. A new bridge service life requirement is 75 years, but the sacrificial thickness of the cofferdams provided only 50 years of protection. Inclusion of cathodic protection extends the service life of the cofferdams by at least 25 years to achieve the overall bridge service life objective. This presentation describes the design and installation of this system.

ABSTRACT: Concrete structures exposed to a marine environment can experience high maintenance costs and reduced service life due to corrosion. This is particularly true for concrete reinforced piles in seawater (or brackish water) where an individual concrete pile can have a variety of exposure conditions including airborne chlorides, periodic wetting by splashing, regular wetting by tidal activity, and fully submerged. Galvanic jacketing systems have been successfully employed to address active corrosion on concrete piles in all exposure conditions. There are different variations of galvanic systems that incorporate zinc-based embedded anodes, stay-in-place forms and submerged bulk zinc anodes. Se-lecting the best galvanic jacket for the application will help to address corrosion-induced deterioration and will preserve and extend the service life of concrete piles in the marine environment.

ABSTRACT: Fluoropolymer coating systems have found widespread use in Japan and the rest of Asia over the last 40 years. This is due to their ability to provide 30+ years of weatherability and corrosion resistance. Regular use of these coating systems in the US has been slower to arrive, but the last 10 years have seen an increase in usage on a range of steel bridge types in this country. Fluoropolymer systems show outstanding weathera-bility, with little change in gloss and color retention for 30 years or longer. Recent test re-sults indicate that these coatings have better corrosion resistance than other high-performance coatings. Fluoropolymer coating systems offer significant life cycle cost sav-ings compared to conventional coatings.

SESSION 3C: MAINTENANCE OF LONG-SPAN BRIDGES

MONDAY, AUGUST 21 ● 4:15 – 6:15 pm ● Gramercy West
Session Chair: Stoyan Stoyanoff, Ph.D., P.Eng., ing. Senior Technical Director, Infrastructure Principal, RWDI, Canada

ABSTRACT: Large-scale suspension bridges are very important infrastructures for supporting national economic activities. However, recently regarding suspension bridges that were built more than 30 years ago, the decline in durability due to local damage from aging is a concern. Damage to the components of cable systems is especially critical since these elements are either irreplaceable or need special techniques for replacement or retrofitting. This paper introduces some examples of the methods involved in improving the durability of cable components, together with the replacement methods for enchanting the service life of suspension bridges.

ABSTRACT: Long-span bridges require specific construction techniques and a constantly renewed design, either due to the evolution of materials, techniques and knowledge, or due to a variable geometry and/or typology that calls for design adaptations.
These exceptional structures generally fall outside the existing regulations and classic frameworks for monitoring and maintenance, whatever the country. In that sense, they require, from the moment they are commissioned, a particular expertise and approach for their continuous monitoring, calling in particular for the production of risk analysis matrices, sensitivity analyses (wind, earthquake, assembly fatigue, etc.), exhaustive maintenance manuals adapted to each structure, regular campaigns of targeted non-destructive tests, while having recourse to particular means of access associated with different types of inspection carried out by qualified and experienced inspectors.
In order to ensure that these structures behave well over time, they are generally monitored, which requires individualized use of the data acquired by the SHMS, whose program can be adapted a posteriori after a period of learning about the actual functioning of the structure.
To complete this monitoring, it is necessary to implement a specific follow-up of the durability of materials and more specifically of reinforced concrete, to carry out updated digital twins associated with adapted management software.
All this specific approach is necessary to have a clear and exhaustive vision of the condition of these structures and the follow-up of their good ageing over time, which sometimes differs significantly from what is foreseen at the time of the design; the objective being in particular to ensure the safety of the operation and the users and to engage the maintenance works at the right time and at the least cost, for a durability which must exceed 120 years for these exceptional and unique structures.
Through emblematic examples, we propose to present these specific approaches implemented on large structures, whether pathological or not, and the proposed management strategies.

ABSTRACT: In recent years there have been several developments to automate the inspec-tion of the free cable length of cable supported bridges by means of robots. Robotic in-spection of cable supported bridges requires a detailed cable investigation of the free cable length but also the anchorage zone. That applies to a broad variety of cable types like stranded cables, grouted parallel wire cables, full locked cables, or open spiral cables.
This article will focus on the robotic detection of Local Faults (LF), the Loss of Metallic Area (LMA) due to wear and corrosion using the Magnetic Rope Testing (MRT) method and the visual detection of defects in the corrosion protection system of the free cable length (e.g. PE-duct) such as cracks and tears using robotic methods. The article will show how robotic solutions are increasingly becoming an integral part of cable inspection pro-jects.

ABSTRACT: The current practices of bridge condition inspection and assessment mainly rely on engineers who perform visual inspection at bridge sites and manually document the inspect results, which are labor-intensive and time-consuming. This research proposes to perform bridge condition inspection and assessment by utilizing robotic platforms such as drones and crawlers that carry various types of sensors such as cameras to collect bridge inspection data. This research develops an approach to automatically detect and quantify realistically complex cracks in concrete bridges based on computer vision and deep learning using photos recorded by cameras. The developed approach is implemented into automatically analyze and interpret photos of strain-hardening cementitious composites with dense microcracks. The results showed that the approach could accurately detect and quantify complex cracks, and the crack assessment results could be utilized to evaluate the remaining load-carrying capacity and durability of cracked strain-hardening cementitious composites. This research promotes the utilization of robots for bridge inspection and condition assessment with high efficiency and high efficacy.

ABSTRACT: When it comes to maintenance of the free cable length of cable supported bridges and structures there has been a strong development in the recent years for semi-automated and fully automated robotic solutions. That applies to a broad variety of cable types like stranded cables, parallel-strand cables, parallel-wire cables, full-locked cables, or open spiral cables.
Focus of this article is on corrosion & UV protection of bridge cables by automated ro-botic wrapping of a multilayer butyl rubber tape system. The advantages of the wrapping are highlighted such as faster execution times, reduced impact on traffic and lane closures, reduced environmental impact as well as the durability of the solution.
In addition, cable wrapping also other robotic supported maintenance services are de-scribed such as robotic welding of PE stay pipes as well as automated cable cleaning. Us-ing example projects across the globe, it is made clear how robotic solutions are increas-ingly becoming an integral part of cable maintenance projects and which role they play within the entire scope of bridge cable maintenance.

SESSION 4A: MAINTENANCE OF CONCRETE BRIDGES

TUESDAY, AUGUST 22 ● 9:25 – 11:25 am ● Nassau
Session Chair: Suhail Albhaisi, PhD, PE, Regional Leader, Bridges, Stantec, New York City, USA

ABSTRACT: Among the test systems for in-place strength available today, two measure the in-place physical strength, pullout and cores. Both systems are dealt with in detail in this paper, the pullout systems named LOK-TEST / CAPO-TEST (ASTM C900-19) and coring (ASTM C42/42M-18). Six testing cases with emphasis on pullout and cores are illustrating different ap-plications:
Case 1. Production testing at the Great Belt Link, Denmark.
Case 2. Service life of bridge pier, Great Belt Link, Denmark.
Case 3. Curing of the cover layer evaluated by pullout and conductivity, Denmark.
Case 4. Strength testing with CAPO-TEST for further loading of old bridges, Poland.
Case 5. In-Situ compressive strength testing of quarantined precast concrete tunnel lining seg-ments using CAPO-TEST, UK.
Case 6. Safe and early loading with LOK-TEST, Canada.
Other cases are given on www.NDTitans.com

ABSTRACT: Corrosion of steel bars is considered as one of the most critical durability issues for bridge pier cap beams, during its service lives. The shear-span to depth ratio (a_v/d) also affect the failure mode, and durability of reinforced concrete (RC) beams. A limited models have been developed for estimating the effects of loss of bond on ultimate strength of beams, particularly those with different shear-span to depth ratios. This study investigates the role of unbonded rebar length L_ub (0%L, 15%L, 30%L and 45%L) on ultimate strength of RC beams, having shear-span to depth ratio (a_v/d) of (2.0, 4.0 and 6.0), respectively. The results suggest that the unbonded rebar length have significant effect on the performance of RC beams with various shear-span to depth ratios. As the unbonded rebar length increases, the failure mode of some RC beams turned from shear failure to flexural failure. Additionally, the ultimate strength, stiffness, and ductility decrease under the same failure mode.

ABSTRACT: In the construction of concrete bridges, the lighter dead load of decks can significantly reduce the number or size of substructure members such as girders, piers and foundations. Although, the arch decks (ADs) ensure superior load carrying capacity and can have longer span length than flat decks (FDs), relatively minute number of studies was performed on longer span decks manufactured as arch shape to maximize the performance. In the previous study, a precast reinforced concrete (RC) AD with enhanced width of 2.5 m was developed. In this study, the behavior of precast RC AD under punching shear load was studied. Three real-scale AD specimens were tested and analyzed to understand its performance under punching shear loading. Different sizes of the ADs were manufactured to evaluate the punching shear capacity. The punching shear capacity and failure mode were obtained from the test, and the results were then compared to various design provisions. Finite Element Analyses (FEAs) were conducted to validate the experiment results and to verify the arching action of the AD with various thicknesses. The study results clearly verified that the AD had a higher or similar load-carrying capacity than the FD due to the arching action caused by the lateral restraint and arch shape, despite of thinner thickness of AD than FD. An analytical and prediction model for the punching shear behavior of ADs was developed and calibrated. The resulting models are described in a code-friendly formulation.

ABSTRACT: This paper introduces a new approach for risk-based selection of inspec-tion methods for external post-tensioning (PT) tendons in segmental bridges. To illustrate the procedure, an actual segmental post-tensioned bridge was used for which the inspec-tion results were available. Hands-on and nondestructive tests were performed on several external PT tendons to investigate their accuracy. The results showed the level of accuracy for the selected methods for the inspection to be adequate for the inspection to continue in large scale. External tendons of the bridge were then inspected using the selected NDE method. The results were used to statistically determine the condition of post tensioning elements using finite element analysis and a deterioration model proposed for post ten-sioning elements. This will facilitate lifetime reliability analysis utilizing the structural model and deterioration model. Although the approach was developed for post tensioned bridges, it can be also adopted for other bridge types.

ABSTRACT: The highway bridges near industrial facilities may experience strand-debonding damage due to the large volume of overloaded trucks. Under frequent overloads, the bond between strands and the surrounding concrete at critical section in bending deteriorates, which results in debonding over that section. Prestressed concrete (PC) bridge girders offer extra flexural strength compared with conventional reinforced concrete bridge, due to their embedded prestressing strands. The level of strength depends on the integrity of the concrete-strand bond in pretensioned concrete girders. Therefore, sufficient strand bond is necessary in PC girders to ensure the transfer of prestressing force and to guarantee the ability of strand to perfectly work on increasing stress once the girder is overloaded. This paper investigates an in-depth analysis on flexural behaviors of a girder-deck system experiencing a strand debonding damage repaired with various strengthening systems, based on finite element software ABAQUS. Two retrofitting techniques were proposed by the use of Carbon Fiber Reinforced Polymer (CFRP) or Steel Plate (SP), and a detailed finite element analysis (FEA) model was developed and verified against the relevant experimental data conducted by other researchers. It was demonstrated that the finite element model could be used to predict flexural behavior for debonding damaged prestressed girder-deck system with strengthening systems. Based on the verified FE model, 51 girder-deck systems were investigated with the consideration of following variables: 1) debonding level, 2) strengthening type, and 3) strengthening material amount. The parametric study was conducted to investigate the effects of above variables on flexural behaviors. It was found that different debonding lengths can significantly affect flexural performance. A longer debonding length for strands has a lower ultimate strength than a relatively shorter debonding length. However, the ductility increases with longer debonding length.

SESSION 4B: RAILWAY BRIDGES

TUESDAY, AUGUST 22 ● 9:25 – 11:25 am ● Gramercy East
Session Chair: Ronnie Medlock, PE, Vice President – Technical Services, High Steel Structures LLC, Lancaster, PA, USA

ABSTRACT: Physical limitations can present challenges when mounting sensor arrays to monitor structures and oftentimes require traffic control, specialized equipment to access hard-to-reach areas, and other imposing safety concerns. However, various measurement techniques have helped engineers to monitor and evaluate different structures despite ac-cessibility challenges. In this study, advanced technologies, and digital image correlation (DIC) techniques are used to monitor deflections of a railway bridge over the Susquehanna River without sensor arrays directly attached to the structure. Deflections of the bridge subjected to live loads from freight and passenger trains were measured with a focus on the truss joints. The dynamic monitoring station utilized high-speed cameras to detect peaks in the time signature and dynamic impact due to axle loads. A series of laboratory tests were conducted to verify the accuracy of the DIC system when tracking cyclic motion over a defined range of frequencies and acceleration amplitudes by which structures are commonly subjected. DIC displacement measurements are compared to the commonly used contact-based method for double integrating the acceleration signal.

ABSTRACT: Physical limitations can present challenges when mounting sensor arrays to monitor structures that are difficult to access without maintenance of traffic control, obtaining equipment for hard-to-reach areas, and other imposing safety concerns. However, various measurement techniques have helped engineers to monitor and evaluate different structures despite accessibility challenges. In this study, advanced technologies, and digital image correlation (DIC) techniques are used to monitor deflections of a railway bridge over the Susquehanna River without mounted sensor arrays. Deflections of the bridge subjected to live loads from freight and passenger trains were measured with a focus on the truss joints. The dynamic monitoring station utilized high-speed cameras to detect peaks in the time signature and dynamic impact due to axle loads. A series of laboratory tests were conducted to verify the accuracy of the DIC system when tracking cyclic motion over a defined range of frequencies and acceleration amplitudes by which structures are commonly subjected. DIC displacement measurements are compared to the commonly used contact-based method of double integrating the acceleration signal. However, in the study, low-cost, microelectromechanical systems (MEMS) accelerometers were utilized, and signal processing techniques were applied to isolate signal noise, especially at high frequencies. The methodologies employed show promise for non-contact, dynamic monitoring of structures using verified non-contact, vision-based measurement techniques and poses the MEMS accelerometers as low-cost long-term structural monitoring solution for a vast range of structures.

ABSTRACT: Rail-structure interaction (RSI) analysis and vehicle-track-structure-interaction (VTSI) analysis are often required during bridge design. For example, the California High-Speed Train Project requires RSI analysis for final design of all structures, as well as VTSI analysis, with the level of interaction to be modeled determined by the complexity of a structure. The goal of RSI analysis is to ensure that superstructure deformations and rail stresses are within acceptable limits. VTSI analysis is a dynamic analysis that takes into account influence of actual trainsets. VTSI Level 1 analysis includes train loads as a series of moving loads. This analysis allows evaluation of dynamic impact effects from trainsets and vertical accelerations of the deck. For complex high-speed railway bridges, VTSI Level 2 might be required, accounting for full dynamic interaction between the trainset and the bridge. To represent this interaction, the trainset is modeled as a multi-body system consisting of rigid bodies, springs, and dashpots. The interaction between wheels and rails is accounted for through kinematic constraints and Lagrange multipliers. This paper presents modeling, RSI, and VTSI analyses of a railway bridge in the LARSA 4D software package. The track and superstructure are modeled in an expedited way using a macro that generates the track, approach, and bridge geometries. Fasteners are modeled as hysteretic springs and automatically positioned along the curved geometry of the track using a LARSA 4D’s bridge path coordinate system definition. RSI analysis is performed accounting for temperature differentials between rails and the deck, vertical train loads, acceleration and braking forces. Break in the rail is introduced using stage construction analysis, followed by progressive collapse analysis (with adapting increments and arc-length control) or nonlinear dynamic analysis. Finally, VTSI Level 1 and 2 analyses are per-formed and the results are compared. Car body accelerations are compared to limit values to ensure passenger comfort.

ABSTRACT: Filler beam decks are structures which utilize closely spaced steel beams that become fully encased in the concrete deck, leaving only the bottom flange exposed. They are shallow depth, durable and robust. There are hundreds of filler beam bridges in Europe that have been in service for many years and carry both rail and highway loads. Filler beam decks were successfully utilized recently for rapid emergency replacements of rail undergrade structures on Metro North’s Hudson Line over Wicker’s Creek in Dobbs Ferry, NY and NJ TRANSIT’s North Coast Line over Laurel Avenue in Holmdel, NJ.

ABSTRACT: This paper presents the design and construction aspects of the foundations for the North Jersey Coast Line (NJCL) Raritan River Bridge Replacement project, which will replace the 115-year-old existing bridge connecting South Amboy and Perth Amboy in New Jersey. The new bridge piers are founded on a cluster of 8.0 feet diameter drilled shafts with shaft tip elevations varying from 180 feet to 230 feet below the water line, which will satisfy the American Railway Engineering and Maintenance-of-Way (AREMA) Manual requirements. This includes limiting the computed longitudinal deflection of the superstructure under load to one inch. Additionally, the new bridge abutments are supported on 24 inch closed-ended steel pipe piles. This paper also discusses the construction aspects of the bridge’s foundation.

SESSION 4C: CABLE-SUPPORTED BRIDGES (I)

TUESDAY, AUGUST 22 ● 9:25 – 11:25 am ● Gramercy West
Session Chair: Joseph Keane, PE, Chief Engineer, MTA Bridges & Tunnels, New York City, USA

ABSTRACT: A 4 km long sea-crossing structure is currently rising out of Storstrømmen in Denmark. The new structure will be one of the few bridges, in the world, carrying a two-track high speed railway and 2 lane road, as well as a combined footway and cycle path, on one single cross section. Comprising 44 viaduct spans and 2 navigational spans. The main bridge will be a cable stay structure with a 100 m tall pylon. The Design & Build Contract was awarded in February 2018, the detailed design is almost complete, with construction well on the way. The paper gives a status of construction at site, details of construction methods chosen by the Contractor, difficulties faced during construction and optimizations of the construction methods developed by the Contractor which are currently being imple-mented. The new bridge will be an outstanding landmark, replacing what was once, Eu-rope’s longest combined road and railway bridge.

ABSTRACT: The paper describes the advancements in the design of materials used to produce the wire rope suspenders for the George Washington Suspension Bridge. These advancements include the steel wire production and coating methods that are designed to increase the life cycle and corrosion resistance of individual suspenders. The advancements result in higher strengths and less maintenance requirements for products in severe service applications. The paper will also discuss the socketing development of the suspender end terminations. The terminations provide enhanced securities for continued service in elevated temperature environments with enhanced coating technologies. The termination design is unique for this project with the design and testing evaluations to be detailed. The wire rope design advancements are becoming prevalent in other structural industry segments and can incorporate load sensing tools for installation practices and long term monitoring of structural performance. All of the improved characteristics are beneficial to the owner of the structure by providing less maintenance requirements to the cables and ultimately a longer service life of the product.

ABSTRACT: The 1915Çanakkale Bridge across the Dardanelles in Türkiye is the longest suspension bridge in the world with a main span of 2023 m. It opened to traffic in 2022. Risk prevention and mitigation were decisive in the development of construction methods for the bridge. Eight lifting gantries were required to erect almost 3.3 km of deck in two months. The innovative lifting gantries were self-erected onto the main cables and devel-oped to minimize disruption to the navigation channel, maximize pre-assembly off the crit-ical path and avoid the use of floating cranes. The paper focuses on the risk-based ap-proach that led to the successful development and implementation of several innovations. It also describes the specialist methods to erect the deck segments near the towers without floating cranes. It ventures into other technological solutions for long span bridge deck erection, placing sustainability at the core of construction engineering and temporary works design.

ABSTRACT: Part of the Netherlands’ busiest highway, the Van Brienenoord bridge comprises 12 lanes of traffic split across the eastbound bridge built in the 1960s and the west-ern bridge built in the 1990s. The Van Brienenoord bridge complex consisting of two parallel 300m span steel arch bridges, approach structures and three parallel bascule bridges over the New Meuse. The bridges carry about 230,000 vehicles daily. A strengthening and replacement strategy was developed to reduce road closures to one of the two bridges at a time and reducing this time to weeks instead of months. The strengthening consists of plate stiffeners to the main girders and arches and a new deck. Construction begins in 2025 and will extend the bridge’s useful life to another 100 years. The strengthening instead of replacing is in line with RWS’ commitment to adopting circular economy principles for their infrastructure network.

ABSTRACT: The ShiZiYang suspension bridge in the GuangDong province in China will when constructed have a world record main span of 2180 m and carry an impressive 2 x 8 lanes of traffic on the two-level truss girder. A bridge of this previously unmatched pro-portion requires innovative design concepts to develop a feasible and constructable bridge. COWI carried out a General Scheme Design in the initial design process to develop a concept for the overall configuration of suspended deck, tower, and cable system. Various alternatives for these main structural components were defined and pros and cons evaluated. Some component alternatives are mutual dependent such that for example the deck structural concept may define the cable system and type of towers. Several concepts were com-pared by a quantitative cost comparison to determine the preferred concept which was subsequently detailed further.

SESSION 5A: ASSESSMENT & RECONSTRUCTION OF BRIDGE DECK

TUESDAY, AUGUST 22 ● 12:50 – 2:50 pm ● Nassau
Session Chair: Hani Nassif, PhD, PE, Professor & Director, Rutgers Infrastructure Monitoring & Evaluation (RIME) Group, Rutgers University, New Jersey, USA

ABSTRACT: Reflection of ground penetrating radar (GPR) amplitudes from rebars is an important parameter for assessing current condition of concrete bridges. GPR reflection amplitudes may be influenced by several factors, including chloride content, rebar corro-sion, and environmental conditions at the time of data collection. The objectives of this study are to observe the change of GPR signals over time and to evaluate the effect of envi-ronmental conditions on GPR reflection amplitudes. A series of six reinforced concrete bridge deck slabs were fabricated with varying chloride contents, from 0.02 percent to 0.1 percent. Corroded rebars were used to examine any corrosion impact on GPR signal atten-uation. In the first testing phase GPR data was recorded daily for 90 consecutive days. Af-ter 90 days, the specimens were sprayed with water, and GPR data was collected to study the effect of surface water on GPR amplitudes. Specimens were then placed in an environ-mental chamber in a second testing phase where relative humidity (RH) was set at three levels. Temperature for each RH level was varied from 5◦C to 40◦C. Both the increased chloride content and rebar corrosion resulted in reduction of GPR reflection amplitudes. GPR reflection amplitude of corroded rebars was found to be smaller than that of non-corroded rebars. GPR reflection amplitudes for concrete specimen with no chloride content decreased by approximately 0.05 dB for every 1◦C increment. The higher the chloride con-tent the higher the GPR reflection amplitude. The RH was observed to have an insignificant effect on GPR reflection amplitudes. This study will greatly benefit the West Virginia De-partment of Transportation as the agency continues to safely preserve over 7,200 bridges.

ABSTRACT: Traditional deck testing techniques (half-cell, chloride sampling, and rein-forcement cover readings), provide useful information but can be destructive (chloride testing), and time consuming in the field. Unlike the more traditional deck testing tech-niques, Ground Penetrating Radar (GPR) collects more data in a much shorter period of time while giving comparable results. With proper data analysis to account for variable re-inforcement cover and asphalt thickness, the information that GPR provides can also help determine what stage of service life the bridge is at.
Once the stage of service life and remaining service life are known, rehabilitation strate-gies can be developed. These rehabilitation strategies then undergo a life cycle analysis via a Monte Carlo simulation to account for uncertainty. Finally, the rehabilitation options may be put through a decision matrix if non-financial factors, such as interference to the public, need to be considered in the evaluation of the final decision. This paper gives details of GPR studies conducted on three projects in Canada.

ABSTRACT: The Verrazzano Narrows Bridge (VNB) is an iconic, irreplaceable span that is integral to the transportation network of the NYC Metropolitan region. The bridge is the longest suspension span in the US with a double-deck mainspan that is heavily traveled, with over 220,000 vehicles crossing each day between Staten Island and Brooklyn and a directional commuter surge in the AM and PM peak periods. This job, known as VN-84AX, is the first of a series of major projects to rehabilitate the VNB upper level approach decks and reconstruct the anchorage spans, which are largely original to the span’s opening in 1964. In recent years, the deteriorating decks have become a source of maintenance needs, with potholes and occasional punch throughs developing.
The project’s scope includes the replacement of 225,000 square feet of bridge deck, superstructure replacement in the anchorage spans, seismic upgrades, two-way cashless tolling implementation, and improvements to lighting, drainage and standpipes within the limits of deck replacement.
All work was performed while maintaining the existing peak hour lane configuration, which has a total of 7 lanes, including a Bus/HOV lane, 4 on the upper level and 3 on the lower level, utilizing a complex Maintenance and Protection of Traffic (MPT) scheme through the use of multiple reversible lanes with Moveable Barrier operations.
This presentation will focus on developing and implementing the Maintenance and Protection of Traffic (MPT) techniques used to manage traffic for the construction of the project, and the innovative approach for superstructure replacement in the anchorage spans with active partnering between the contractor and designers to accelerate construction.

ABSTRACT: A pilot project study was conducted for protection of a new concrete deck of a long span bridge, using thin polymer overlays. Various overlay materials and systems were considered, out of which two primary systems were considered, specifically two-layer epoxy and one-layer Methyl Methacrylate systems. Field testing was the next step. Initially, test patches consisting of single-span and one lane-width were installed, one for each system, and later inspected and evaluated for long-term performance. Subsequently, prototype installation of thin overlay on multiple spans (single-lane) was done, for each of the two systems. The success of this pilot study resulted in application of thin overlay over the remaining deck areas of the subject bridge. This paper will include description of the various phases of this project and technical comparison of the selected two polymer systems. In summary, both systems are effective for protecting a concrete deck that is either newly constructed or in reasonably good condition. The epoxy system is easier to work with, but is limited to favorable warm weather. In contrast, the Methyl Methacrylate system is harder to install, but it can be applied without weather limitation.

ABSTRACT: Fiber-reinforced polymer (FRP) materials have been widely accepted to retrofit deteriorated infrastructure. Despite the advancement in FRP techniques, inspection of its installation presents a significant challenge to its widespread use. To ensure durability and capacity of externally bonded FRP structures, it is critical to evaluate the potential for debonding failure and surface defects. In this study, experimental and theoretical investigations on employing ground-penetrating radar (GPR) and infrared tomography (IRT) methods were carried out to evaluate bridge deck slabs externally bonded with glass FRP (GFRP), carbon FRP (CFRP), and a combination thereof. Eight externally bonded FRP concrete deck slab specimens were prepared: three with CFRP, four with GFRP, and one with hybrid CFRP/GFRP. Cracks, voids, and debonding were artificially made on the surface of the concrete deck slabs. Test variables include location and size of surface voids, and rebar depths. Improved 2-D and 3-D image reconstruction using synthetic aperture focusing technique (SAFT) was established to effectively interpret GPR data collected. The results showed that the developed software, using the enhanced image reconstruction technique, provides clear and high-resolution images of the FRP-strengthened deck slabs in comparison to those obtained from the device’s software. Test data revealed that the GPR technique could accurately determine rebar depths as well as depth, size, and location of artificial voids. The GRP, however, could not well predict debonding and cracking. Results obtained from IRT images indicated that it could detect and locate near-surface defects with a good accuracy. The study suggests that the combination of the GPR and IRT techniques can be effectively assess internal defects of FRP-strengthened concrete bridges.

SESSION 5B: RELIABILITY-BASED ANALYSIS AND EVALUATION

TUESDAY, AUGUST 22 ● 12:50 – 2:50 pm ● Gramercy East
Session Chair: Andrzej S. Nowak, Professor and Chair, Department of Civil and Environmental Engineering, Auburn University, Alabama, USA

ABSTRACT: Dewberry was the lead designer on this complex Design-Build project with contractor Posillico/El Sol Joint Venture for the New York State Department of Transporta-tion. This contract was the first phase of a three-phase project which will increase capacity on the Van Wyck Expressway between Kew Gardens Interchange and JFK Airport in order to improve access to and from the airport. The scope of work included the reconstruction and lengthening of nine overpass bridges to accommodate a widened Van Wyck Express-way which will be constructed in the third phase. The project location was a dense urban neighborhood in Queens requiring extensive coordination and innovative design solutions in order to minimize impacts to traffic on the expressway, overpass bridges, service roads, numerous vital utilities, and the PANYNJ Air Train which runs above seven of the nine bridges. One key strategy was utilizing a top-down construction method for the new abut-ments where the existing abutments were left in place, new abutment pile caps were con-structed behind them, and finally a new concrete abutment wall facing was constructed from the new pile cap down to the roadway level after removing the existing abutments. Despite a multitude of challenges, this project was constructed with minimal delays or im-pacts to the community and traveling public.

ABSTRACT: In steel girder bridges, girders are typically connected by cross-frames at different locations along their length. Cross-frames provide lateral-load resistance to the steel girders during construction and reduce the unbraced length of the compression flanges of steel girders. Moreover, cross-frames are thought to have a beneficial impact on girder load distribution. Once the simply supported composite bridge is constructed, the only theoretical purpose of the cross frames is live load distribution. However, prior works by various authors that have investigated the role of cross-frames in live load distribution concluded that the role of cross-frames in distributing the live load is minimal. On the other hand, cross-frames cause numerous complications for steel girders, including fatigue issues, warping and lateral bending stresses that differ from designers expectations, significant fabrication costs, and construction fit-up issues. So, to reevaluate the role of cross-frames in steel bridges, two tests were conducted for a decommissioned bridge in New Castle County, Delaware: one at the in-service stage with cross-frames and the other a destructive test conducted after removing all the intermediate cross-frames. During these tests, the bridge’s girders were instrumented with strain gauges in various locations along their length. The results of these two tests were used to compare the bridge’s performance due to transverse load distribution, web distortion, and forces induced on the girders by the cross-frames.

ABSTRACT: The impact of climate change on global infrastructure systems is becoming increasingly apparent and concerning, with severe weather events exacerbating the already-existing stress on aging infrastructure. Despite the guidance of building codes and standards, primarily developed based on historical data, the risk of infrastructure failure due to climate change is growing, making it crucial to assess and adapt to these risks. However, assessing and evaluating climate change risk on bridge infrastructure presents a challenge for practitioners and decision-makers. This paper discusses the need for a multi-objective and multi-hazard risk assessment method to evaluate the impact of climate change on bridge structures. The framework proposed includes integrating the fuzzy analytical hierarchy process to create a risk assessment methodology that evaluates bridges structurally and socioeconomically. The objective is to create a system that empowers practitioners and decision-makers to make well-informed decisions regarding the risk level to bridges caused by anticipated climatic factors.

ABSTRACT: Bridges are exposed to many extreme conditions, such as floods, scour, and severe dynamic loads, e.g. earthquake, blast, vehicular impact, and they are frequently damaged or even collapse during such events. The continued stability and performance of a damaged bridge can be broadly attributed to “redundancy”, and it is usually quantified based on the behavior of bridges following member failure(s). Unfortunately, redundancy and ability of bridges to mobilize alternative load paths for damaged bridges have not been well understood. Moreover, traditional design approaches are unable to provide explicit measures of residual safety of bridges subjected to damage or failure of members. In this study, a basic framework is proposed for deterministic assessment of robustness of bridges that can be used in design offices. Four different types of bridges were selected to develop this framework. Failure or damage of members of the bridges was simulated through sudden member removal in LS-DYNA. Behavior of the bridges under various damage scenarios was evaluated quantitatively through the performance indicators such as deflection of the bridge or girders, effective plastic strain, rotation of girders. Compared to the current approaches such as pushdown analysis, the proposed approach has several advantages, (1) it is a deterministic approach where the bridge performance under various damage scenarios for all structural members can be evaluated thoroughly and quantitatively, (2) it is straightforward and simulates actual damage scenarios with realistic loads, such as extreme load combination for dead and live loads, dynamic effect can be included, and (3) critical members or locations of bridges and the related ranking can be identified and the results can be easily used to strengthen bridges for an improved robustness against potential damage or member failure.

ABSTRACT: A bridge in Turkey constructed with balanced cantilever method has been studied for the assessment of the bridge for its current situation. The bridge is 30 years old and has four main spans with 115 m and two side spans with 72 m. Total length of the bridge is 604 m. The superstructure of the bridge is a monocell reinforced concrete box girder with variable depths throughout the span length. The post tensioning tendons of the section are internal and external. Some of the external tendons are damaged and need to be replaced. Expansion joints need to be repaired and some of them need to be replaced. There are some concrete surfaces exposed to water leaking from the expansion joints and they have deteriorated and need to be repaired. This paper includes the structural analysis of the bridge, engineering calculations and planning for the maintenance and repair works. The bridge was modeled using finite element analysis software including construction stage analysis. In addition, the current performance of the bridge considering the time dependent deformations based on the time passed in the service was obtained by the help of the analysis model. The replacement of damaged external tendons was studied one by one in the structural model. Visual inspection performed inside the section revealed the current situation of the bridge. Bridge inspection, maintenance and rehabilitation is very important and need to be planned for each and every bridge structure. That is important to provide safety and assure structural performance along the planned service life of the structure.

SESSION 5C: BRIDGE CABLE EVALUATION & AERODYNAMICS (II)

TUESDAY, AUGUST 22 ● 12:50 – 2:50 pm ● Gramercy West
Session Chair: Khaled Mahmoud, PhD, PE, Chief Bridge Engineer, BTC, New York City, USA

ABSTRACT: The Bronx-Whitestone Bridge was designed during the 1930s in an era of suspension bridges with decks stiffened by shallow plate girders, many of which were subsequently found to be vulnerable to aerodynamic instabilities such as vortex shedding and flutter. Following the occurrence of mild and benign wind-induced oscillations in the first several years after opening in 1939, the bridge has undergone a series of retrofits, from structural solutions such as stay cables, stiffening trusses, and a steel orthotropic deck, to aerodynamic enhancements such as a tuned mass damper and wind fairings. Wind tunnel studies in 2015 confirmed the improved aerodynamic performance due to the recently installed wind fairing system and stiffer orthotropic deck. A subsequent rehabilitation project gave the opportunity to assess measures to further improve the aerodynamic performance of the bridge. A 3ft tall solid screen added on top of the median barrier was found to act as an above-deck vertical baffle plate, disrupting the alternating pattern of vortices, reducing the susceptibility of the bridge to instabilities. This led to the conceptual design of a Median Barrier Extension (MBE) comprised of 3ft solid transparent acrylic panels fixed to the top of the existing median barrier posts, supported by a tubular steel frame. To ensure this unique barrier modification met current industry safety standards, the MBE design was iterated through a crash analysis study using non-linear finite element models before the final design proceeded to a full-scale physical crash testing program to MASH Test Level 4. This paper presents the full timeline of this innovative retrofit project, from conception during wind tunnel testing, through to design, crashworthiness studies and final construction in 2020. This project has demonstrated that a vertical extension to a median barrier can act as a simple and cost-effective enhancement to the aerodynamic performance of existing bridges.

ABSTRACT: This paper presents a study on the introduction of an arch rib onto a deteriorating cable-stayed bridge. The research found that introducing an arch rib significantly reduces axial force, bending moments, tension on the cable, and deflection of the main girder. Additionally, the ultimate strength of the bridge was examined through a comparative study between non-deteriorated cable-stayed bridges and inclined suspension arch bridges. The study found that the ultimate strength increased by more than three times with the introduction of an arch rib. The visual impact of the bridge was also investigated using 3D CAD diagrams, Computer Graphics (CG) diagrams, and videos, and it was determined that the scale and visual balance with the surrounding environment are essential factors.

ABSTRACT: New long-span bridges must be designed for climate resiliency based on historical records and long-term predictions. Existing bridges must be rehabilitated for climate resiliency to ensure safe operation and increased longevity. A multi-hazard assessment combined with bridge monitoring, wind tunnel studies and numerical analysis can provide an accurate picture of the current state of the bridge as a whole and specific components of the bridge, including cables, deck, and hangers. Bridge microclimate past, present and future can be modelled, and climate scenarios can be applied to a digital bridge model to predict the structure’s response to the wind storms of tomorrow and to develop a framework of climate change adaption.
The authors will illustrate how aerodynamic and climate engineering consulting can inform decisions about the design and rehabilitation of long-span bridges using case studies. Aerodynamic and climate consulting early in the design process contributes to both design, material, and carbon cost savings. Aerodynamic consulting and climate (weather) forecasting in construction stage planning ensure the safe, efficient, and cost-effective construction of a bridge or a bridge rehabilitation plan.
A case study of the design of a new signature long-span bridge, case studies of bridge cables and hangers and a case study of a bridge rehabilitation will be detailed to outline the benefits of early-stage aerodynamic and climate consulting.

SESSION 6A: BRIDGE INSTRUMENTATION & MONITORING

TUESDAY, AUGUST 22 ● 3:35 – 5:55 pm ● Nassau
Session Chair: Wael Zatar, PhD, FPCI, Dean, College of Information Technology and Engineering, Marshall University, West Virginia, USA

ABSTRACT: The management of bridge assets is essential to maintaining a functioning transportation network throughout the United States. The ability to conduct traditional in-spections is sometimes limited due to cost, safety, or access. DOTs have recently started incorporating the use of uncrewed aerial vehicles (UAVs) to inspect otherwise difficult to reach areas, and to quickly monitor different areas of the bridge. The current study demonstrates the application of UAVs for conducting 360° inspections of a long curved bridge and a wide bridge. Multiple key observations were made during the data collection, processing, analysis, and data management. The approach adopted in this study is ex-pected to result in significant savings in terms of data collection and storage costs. This study is expected to provide the DOTs with an idea about feasibility of using these data collection tools for monitoring bridge infrastructure.

Keywords: Infrastructure, Bridges, UAV, 360° Inspection, Savings

ABSTRACT: Over the coming years, bridges and other physical infrastructure will experience unprecedented demands due to extreme weather and trends in freight. These in-creasing demands are set against a backdrop of infrastructure deterioration as many assets reach the end of their intended service life. Bridge owners have done a significant amount of work to identify vulnerabilities in their infrastructure but challenges such as budget constraints and environmental complexities limit their ability to adapt.
The proper application of technology, however, can help bridge owners safely extend the useful life of their structures. This can be done by gathering information that can be used to optimize lifecycle costs, to better quantify vulnerabilities, and maintain situational awareness to mitigate risk. This is particularly important for long-span bridges which re-quire a disproportionate amount of maintenance expenditures and would cost billions of dollars to replace. However, there are still multiple challenges to deploying a cost-effective structural monitoring system that provides easily understandable and actionable information. This paper will provide an overview of the current practice of managing long-span bridges using structural monitoring (SM), examining both new and existing bridges. The paper will draw on the authors’ combined experience working with numerous bridges, each with more than one hundred sensors. The need for new and improved resources for handling the large amounts of data generated by these systems will then be discussed. Finally, a vision for the future of SM for long-span bridges will be presented.

ABSTRACT: The Ile de Re viaduct located in France was built in 1988 and has 27 spans over 2840m in total length. It has about 300 external post-tensioned cables to support the bridge. Sixense has inspected 85 anchorages using ultrasonic testing and installed 170 acoustic sensors to monitor the bridge. This presentation would detail the UScan tests and results, as well as the SHMS installed on the bridge.

ABSTRACT: Beam deterioration in steel bridges due to corrosion is a critical problem in the bridges of the northern United States, particularly in New England. We have seen that water, ice melt chemicals, and malfunctioning expansion joints greatly contribute to steel beam end corrosion.
In the current research work, our team is utilizing LiDAR and other scanning technologies in order to measure section loss and to capture the corrosion/damage pattern present in a given corroded beam end. We are able to generate a thickness contour and estimate the capacity of the corroded end using our in-house created codes and methods. The contours and heat maps generated have immense detail and are the result of millions of points extracted from point clouds. These methodologies also allow for the validation of our real loading tests that we perform in our lab. Our group is delving into the influence that different scanners, methods, and scanning components have on the overall result.
We have been exploring the use of several 3D scanners, training AI for capacity estimation, and locating severe section loss where additive manufacturing is being explored as a method of beam end repair. We find that LiDAR and 3D scanning technologies prove to be innovative in the future of bridge inspection.

ABSTRACT: The 1915Canakkale bridge in Turkey is the longest suspension bridge in the world with its 2023m main span. Sixense is installing the biggest SHM System ever installed on a bridge with more than 1000 sensors. This will allow to monitor the environment of the bridge, its structural behavior and its ageing. Data will also allow to predict the evolution and anticipate maintenance.

ABSTRACT: Infrastructure monitoring has been gaining substantial attention over recent years. What is lacking from this attention is the community engagement and outreach component. This is essential in making end users more comfortable in monitoring infrastructure while making the technology less expensive and more accessible. Flooding, wildfires, sporadic downpours, and many other natural events put communities at risk due to the failure of bridges and other forms of structural infrastructure. Therefore, with higher community involvement in understanding and utilizing new sensing technologies, there is more to be gained in preparing for and mitigating the effects of natural hazards. The research team developed a Low-cost Efficient Wireless Intelligent Sensor (LEWIS) platform to give communities the ability to create innovative monitoring solutions, including informing how to prepare to post wildfire flooding events. The LEWIS platform can be modified for a diverse array of purposes and in partnership with communities, clients, and their needs. LEWIS sensors are low-cost, rapidly fabricated, and low maintenance. Deploying a network of LEWIS sensors is rapid and can sustain the diversity of weather conditions to meet community needs in a reliable manner. A network of LEWIS sensors is wireless and interconnected via hotspot and the collected data is accessible remotely via website. LEWIS sensors provide accurate and consistent data acquisition on environmental phenomena and their impacts, which allows for communities to make smart decisions on how they build, adapt their infrastructure, and how they plan solutions for damages from potential or previous natural events. This presentation briefly discusses LEWIS platform and community (from student to industry professional) engagement efforts.

SESSION 6B: BRIDGE DESIGN (II)

TUESDAY, AUGUST 22 ● 3:35 – 5:55 pm ● Gramercy East
Session Chair: Ronald J. Watson, CEO, RJ Watson Inc., Alden, New York, USA

ABSTRACT: One of the ways wind interacts with bridges is to make noise. Usually this “aeroacoustic” (wind induced) noise is insignificant. However, in some cases bridge ele-ments make significant tonal noise that can be heard miles away. Such problems are often extremely annoying, difficult to solve, and newsworthy, as aeroacoustic issues are rare and conspicuous. Aeroacoustic issues can be prevented if addressed early in design stage, avoiding costly post-construction modifications. Through detailed analysis integrating ex-pertise in wind climate, acoustics, fluid-structure interactions, and wind tunnel testing, po-tential aeroacoustic noise issues can be flagged. In most cases, the risk can be mitigated through small design changes. When high risk issues are anticipated, or have been ob-served post-construction, on-site measurements or wind tunnel testing can be completed to identify the character and severity of noise produced. In understanding the specific condi-tions and root cause of the mechanism of the noise, a solution that works in the context of the project can be developed.

ABSTRACT: This paper focuses on the design challenges of a Texas U-Turns interchange supported by the Skillman Arch Underpass Bridge located in Dallas, Texas. The geometric challenges to include all traffic movements, U-turns and multi-use paths resulted in an ex-tremely wide tied-arch structure and these challenges are presented in detail. It is currently under construction and will serve to convey traffic on Skillman Street over IH635/LBJ Freeway in the Lake Highlands Area. With the U-turn ramps, the bridge is very wide for a single arch bridge structure at 217 feet accommodating 14 lanes of traffic and shared use paths. The turn-around lanes required cantilevering floor beams to accommodate traffic lanes outside of the arch’s tie-girders with long cantilevers. The span is 288.5 feet long. Due to the turning requirements of trucks, the left turn movements precluded the inclusion of a full center arch rib requiring unique arch bracing. The bridge design utilizes a network of inclined cable-stayed hangers on each arch that made the tie girder more efficient and enhanced the system redundancy. Discussion includes the foundation design and design challenges of the 10º canted arches, including arch ribs, tie-girder, hangers, knuckle region and geometrically challenging bracing of the partial center arch rib. The design challenges in the deck and floor beam system are included along with construction driven decisions. Aesthetic requirements with complex lighting requirements and the related influences on the design are also discussed. Finally, redundancy design and rulings by FHWA on inter-nal redundancy with tie-cables within the tie-girders are also presented.

ABSTRACT: Connected and Autonomous Vehicle (CAV) technology is advancing in the United States and abroad. The technology allows two or more vehicles equipped with state-of-the-art driving support systems to travel closely forming a platoon with the vehicles driven by Intelligent Transportation Systems technology, and mutually communicating along a certain distance. Potential benefits of truck platooning include reduction in driver numbers, improved safety, and greater fuel efficiency. Because of its potential benefits, several states and the FHWA performed truck platoon demonstrations.
The technology also creates challenges to the management and preservation of current transportation infrastructure assets. Travel over bridges in platoons of trucks and buses may produce greater load effects than those produced by individual vehicles. Limited information on the effects of truck platoons on bridges exists in the literature. Work under this study investigated truck platooning impacts on bridges on major highway systems, primarily focusing on the strength limit state. In addition, the focus was on the major highway systems platoons are likely to use.
The work in this project included the review of weigh-in-motion (WIM) data to determine the most common truck configurations and to select a representative truck configuration. In addition, the study also included two American Association of State Highway and Transportation Officials (AASHTO) trucks, the Type 3-3 and the 3S2 trucks. Two-, three-, and four-truck platoons with spacing of 30, 50, and 70 feet were included in the study. The bridge span lengths considered ranged from 30 to 300 foot simple and continuous spans.
The purpose of the study was to identify most probable truck configurations, limitations imposed by the load capacity of existing bridges and to identify existing bridges that will potentially be impacted by truck platoons. This presentation will give an overview of the technology and the results of the study.

ABSTRACT: The Gordie Howe International Bridge (GHIB) crossing the Detroit River be-tween Windsor (Canada) and Detroit (USA) will be the longest cable stayed bridge in North America. With a main span of 853 m / 2800 feet, the GHIB will also set the record as hav-ing the longest cable stayed composite span in the world. This paper presents an overview and note-worthy de-sign features including foundation, tower, superstructure, and high-lights design considerations in the areas of aerodynamics, stay cables, redundancy and du-rability.

ABSTRACT: Tintagel Castle is among the most popular tourist destinations in England. Built in the 13th century, it is a unique historical site on the windswept north coast of Cornwall. The castle’s location makes it difficult to access. Up until now, it has been reached via an arduous approach involving many stairs which was difficult or impossible for people with mobility challenges. To improve accessibility to this historic site, an elegant cantilevered bridge was designed and constructed. The Tintagel Castle Bridge is unlike most pedestrian crossings as its design has two cantilevers that don’t quite meet, creating a small gap in the middle. Situated on a site that is prone to extreme weather, this presented an engineering challenge to ensure maximum stability.
This presentation will provide an overview of the engineering approach taken to overcome the climate and topographical conditions influencing design to ensure a safe and comfortable structure. Wind tunnel testing assessed numerous aspects of the bridge’s aerodynamic and aeroelastic performance, such as the susceptibility to flutter and vortex shedding. Through the example case study, participants will gain a better understanding of optimizing bridge designs to withstand wind and other environmental influences without developing undesirable dynamic responses.

ABSTRACT: Connected and Autonomous Vehicle (CAV) technology is advancing in the United States and abroad. The technology allows two or more vehicles equipped with state-of-the-art driving support systems to travel closely forming a platoon with the vehicles driven by Intelligent Transportation Systems technology, and mutually communicating along a certain distance. Potential benefits of truck platooning include reduction in driver numbers, improved safety, and greater fuel efficiency. Because of its potential benefits, several states and the FHWA performed truck platoon demonstrations.
The technology also creates challenges to the management and preservation of current transportation infrastructure assets. Travel over bridges in platoons of trucks and buses may produce greater load effects than those produced by individual vehicles. Limited information on the effects of truck platoons on bridges exists in the literature. Work under this study investigated truck platooning impacts on bridges on major highway systems, primarily focusing on the strength limit state. In addition, the focus was on the major highway systems platoons are likely to use.
The work in this project included the review of weigh-in-motion (WIM) data to determine the most common truck configurations and to select a representative truck configuration. In addition, the study also included two American Association of State Highway and Transportation Officials (AASHTO) trucks, the Type 3-3 and the 3S2 trucks. Two-, three-, and four-truck platoons with spacing of 30, 50, and 70 feet were included in the study. The bridge span lengths considered ranged from 30 to 300 foot simple and continuous spans.
The purpose of the study was to identify most probable truck configurations, limitations imposed by the load capacity of existing bridges and to identify existing bridges that will potentially be impacted by truck platoons. This presentation will give an overview of the technology and the results of the study.

SESSION 6C: CABLE-SUPPORTED BRIDGES (II)

TUESDAY, AUGUST 22 ● 3:35 – 5:55 pm ● Gramercy West
Session Chair: Timothy Klein, PE, Principal Fabrication Engineer, WireCo, USA

ABSTRACT: The Maryland Transportation Authority (MDTA) owns and operates the William Preston Lane, Jr. (Chesapeake Bay) Bridge, a twin suspension bridge that connects Annapolis to Maryland’s eastern shore. As part of a complete program management of the cables for these two critical structures, MDTA has implemented several preservation practices, including cable dehumidification systems on both bridges, completed in 2015. In 2020, a supplemental cable system was installed on the Westbound Bridge. Detailed analysis models were created for load transfer analysis and incorporated the survey information provided by the Contractor, including slight variations in towers. This analysis model was used to establish the length of the different components of the supplementary suspension system in their free cable (as-installed) condition and at the completion of the load transfer process, and to analyze the forces on the components of the supplementary for each step of load transfer. The installation of the supplemental cable system extends the service life of the existing suspension spans and improves durability and performance. This demonstrates the effectiveness of complex design, analysis and construction methods for the rehabilitation of the suspension systems, compared to replacement alternatives.

ABSTRACT: Full Locked Coil (FLC) Ropes were first patented in the early 20th century. Currently they are utilized in all kinds of structures defined by lightweight aesthetics, such as stadium roofs, membrane roofs, pedestrian bridges, and glass facades, as well as in applications with a more functional focus, such as stayed masts, pedestrian bridges, vehicular bridges, and pipeline bridges. Despite their wide range of applications and advantages over other tension members, structural engineers and architects are unaware of the benefits FLCs provide to the designer.
The paper will compare the design and the mechanical properties – like weight to load bearing ratio, stiffness, pre-stretching, pre-tensioning and corrosion protection – of a FLC to other types of rope – such as Spiral Strand Rope, Stranded Rope, and Bridge Rope – and other tensions members – e.g., round steel bars – and present the advantages and disadvantages a FLC has in comparison.
The paper will also describe how FLC ropes are designed and manufactured according to current standards and unique demands of different structural applications. Additionally, it will provide an overview of landmark structures that incorporate FLC technology in their design.

ABSTRACT: This paper studies aspects of the structural cable system used to support the Dublin Link Suspension Bridge, located in Dublin, Ohio. Credit for the structure in-clude the City of Dublin Ohio, Paul Endres of Enderstudio, TY Lin, Kokosing, Genesis Structures, Michael Baker, Schlaich Bergermann Partner and Teufelberger Redaelli. The mixed-use pedestrian cycle bridge provides a new connection between the Riverside Crossing Park on the East side with Dublin’s historic district over the Scioto River bringing together two communities which “serves as landmark for the City of Dublin representing connectivity and inclusivity” the words of Dublin’s Deputy City Manager. The bridge has a span of 761 feet (232m), is 14 feet (4.3m) wide with a 502 feet (153m) suspension span in a reverse curve. The bridge is characterized by a single needle shape concrete mast, an “S” shape deck and cable hangers that connect to only one side of the deck. The large di-ameter main catenary cables are split and connected at the mast top and deck with a neat connection avoiding the need for a traditional large saddle casting that was deemed to have been visually obtrusive. Teufelberger-Redaelli designed, manufactured, supplied, and in-stalled the two main catenary cables, the tie down cable, the hanger cable and restrainer ca-ble system including clamps as well as the specifically designed spherical socket pins and washers which accommodate rotations between the cable sockets and the anchor plates under live load events. This paper will explore some of the challenges associated with the cable supply and installation including the industry leading, specialist cable fatigue testing program that was specifically adopted for this project.

ABSTRACT: Long-span bridges play a critical role in the current transportation infrastructure system. However, they are frequently exposed to many extreme hazards, e.g., hurricanes, earthquake, blast, or impact, etc. In spite of their importance, the structural robustness of these long-span bridges has not been well understood. Traditional design approaches are unable to provide explicit measures of the residual safety of long-span bridges under damages due to multi-hazards. Additionally, the current evaluation approach based on redundancy were mainly developed for regular short-to-medium span bridges, not for long-span bridges. Thus, a new robustness evaluation approach is proposed for short, medium and long-span bridges in this research and it can account for and estimate the structural robustness corresponding to various user-specified initiating events and various user-specified limit states on a common and unified basis, which cannot be done by existing approaches. Thus, it can be adopted as a comprehensive tool to assess the safety of bridges in their intact and damaged conditions to facilitate critical decisions on design and retrofit needs. To illustrate the applicability and versatility of the approach, three long-span cable-supported bridges (a cable-stayed bridge, a tied-arch bridge, and a suspension bridge) were selected. With the detailed finite element models devolved in LS-DYNA, the structural robustness of these long-span bridges were investigated thoroughly under both the intact condition and the damaged condition due to single cable loss. The results showed that: (1) the effect of single cable loss on each bridge can be captured explicitly, demonstrating the applicability of the new method, especially for long-span bridges, and (2) despite the adverse effects of single cable loss, there was no significant reduction in the reliability and robustness of all three bridges, i.e., they are very robust against single cable loss scenarios.

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