Wednesday, July 15, 2025
Technical Sessions
Structural Health Monitoring
Time: 8:00-10:00 AM
IBC 25-58: Truss Panels Replacement and Structural Monitoring, Pulaski Skyway Span 47
Vincent Liang, GPI, Bridgewater, NJ; Han-kil Lee, GPI, Bridgewater, NJ; Lenny Lembersky, GPI, Bridgewater, NJ
The New Jersey Department of Transportation (NJDOT) commissioned Greenman-Pedersen, Inc. (GPI) to design the rehabilitation of Spans 45 to 61 of the 93-year-old Pulaski Skyway. These deck truss spans, ranging from 175 to 300 feet long, feature truss expansion mechanisms and joints at alternating spans. Due to severe corrosion, truss panels adjacent to these joints require replacement. GPI proposed an innovative solution: using shoring towers on micropile foundations to temporarily support the truss and floorbeams while replacing affected chords, all while maintaining traffic flow. The rehabilitation process utilizes a sophisticated jacking procedure designed to reverse dead load stresses and isolate a portion of the truss from live loads using a floorbeam support system. A prototype contract for Span 47 was recommended to validate the design concept, reconstruction sequence, and jacking procedure through structural monitoring before extending the rehabilitation to the remaining spans.
GPI conducted non-linear staged construction structural analysis using CSiBridge to determine jacking loads and calculate structural responses. These results were verified during construction through extensive real-time monitoring of stresses and displacements at each stage of jacking and replacement. Additionally, destructive testing of removed corroded elements was performed to assess and validate estimated pack-rust buildup and section loss.
This paper focuses on the specified construction sequence and the truss’s response during dead load reversal jacking, chord cutting and replacement, and final jack down, as revealed by structural monitoring results.
IBC 25-59: In-site testing data analysis of Kinmen bridge
ChinKuo Huang, China Engineering Consultant, Inc., Taipei City, Taiwan; Fsin-Chu Tsai, China Engineering Consultant, Inc., Taipei City Taiwan; Li-Ting Chung, China Engineering Consultant, Inc., Taipei City, Taiwan
The Kinmen Bridge is located in Kinmen County, connecting Kinmen Island and Lieyu Island at both ends. The bridge is 4.77 kilometers long, with a main bridge section of a 6-span and 5-tower cable-stay bridge, measuring 1050 meters in length, two side span of 125 meters, and four main spans of 200 meters each. Due to its location in a severe marine corrosion environment, the maintenance and upkeep conditions of the Kinmen Bridge are quite strict. In order to ensure the safety of pedestrians and the benefits of sightseeing, a bridge monitoring system is gradually established during the bridge construction period. And after the establishment of the monitoring system, ambient vibration tests, cable modal detection tests, load tests, etc. are carried out to collect data on the completion status of the bridge, and the test data is analyzed and organized as a reference for subsequent tracking, management, and maintenance.
IBC 25-60: Extending Service Life to 200 Years: Insights from 30 Years of Optimizing Corrosion Sensor Use at the Great Belt Link
Peter Møller, Rambøll Danmark A/S, København S, Denmark; Kim Obel Nielsen, Rambøll Danmark A/S, København S Denmark; Anders Bøwig Brøndum, Rambøll Danmark A/S, København S, Denmark; Svend Gjerding, Sund & Bælt Holding A/S, Copenhagen V, Denmark
The Great Belt Link, originally designed for a 100-year service life, has benefited from 25 years of corrosion monitoring, providing key insights to extend its durability to 200 years. This study emphasizes the critical role of corrosion control in the splash zone, where traditional methods like chloride testing fall short. Real-time corrosion sensors, installed between the waterline and +2.5 meters, revealed complex corrosion dynamics caused by macro-cell formation, reduced oxygen access, and environmental factors such as wind and tidal forces.
Key findings demonstrated that early installation of galvanic anodes in submerged sections effectively delayed corrosion initiation, with greater benefits when installed proactively. Although underwater installation costs were moderate, splash zone installations were more complex; however, the resulting reductions in future repair costs justified these expenses. The use of cathodic protection, combined with Linear Polarization Resistance (LPR) and advanced non-destructive testing (NDT) techniques, allowed for accurate real-time corrosion assessments, reducing the need for invasive testing and enabling strategic, cost-effective maintenance.
The Great Belt Link’s proactive corrosion management strategy addresses challenges common to large bridges worldwide, where exposure to seawater, temperature fluctuations, and constant moisture cycles accelerate corrosion. The innovative monitoring approach at Great Belt is essential for areas like the splash zone, notorious for high corrosion rates and complex deterioration mechanisms. This strategy sets a new standard for corrosion control, ensuring that critical infrastructure can meet increased service life requirements with minimal environmental impact and maintenance demands.
IBC 25-61: Bearing Rehabilitation and Replacement on the Great Belt Link West Bridge
Lars Thormann, Rambøll Danmark A/S, Copenhagen S, Denmark; Claus Pedersen, Rambøll Danmark A/S, Copenhagen S, Denmark; Jens Fogh Svensson, Rambøll Danmark A/S, Copenhagen S, Denmark; David Lang, Rambøll Danmark A/S, Copenhagen S, Denmark; Niclas Grønkjær Rasmussen, Rambøll Danmark A/S, Copenhagen S, Denmark
The Great Belt Fixed Link is an 18 km rail and road corridor featuring a tunnel, a suspension bridge, and the 6.6 km multi-span concrete box-girder Storebælt West Bridge. As the only railway connection between Zealand and Funen, it is essential for linking Denmark with Sweden and central Europe. The West Bridge relies on 276 structural bearings supporting its two box girders, one for road and one for rail. Given the bearings’ shorter service life relative to the bridge’s expected 200 years, a comprehensive bearing renovation and replacement program has been initiated.
The program employs a digital-enabled maintenance strategy that combines in-depth inspections with structural health monitoring for a thorough evaluation of bearing conditions. This approach provides a holistic framework to plan and phase the replacement and renovation of bearings, ensuring minimal disruption to bridge traffic and sustained structural health.
Several technical challenges define this program, especially working in harsh marine
Analysis/Research/Design III
Time: 10:30-12:00 Noon
IBC 25-62: Steel Bridge Design Resources for Efficient Conceptual Design Decisions
Brandon Chavel, National Steel Bridge Alliance, Chicago, IL; Jeff Carlson, National Steel Bridge Alliance, Chicago, IL
The National Steel Bridge Alliance has a suite of resources that can help bridge designers and owners make effective and speedy decisions in the preliminary design phase that will result in an efficient steel bridge. When used in combination, these resources can allow engineers to compare various span arrangements, girder spacings, and girder sizes in a matter of hours. These resources include the Steel Span to Weight Curves, the new Steel Girder Bridge Design Standards, LRFD Simon, and NSBA Splice.
The Steel Span to Weight Curves are the quickest way to determine the weight of steel per square foot of bridge deck for plate girder bridges, and are ideal for comparing various span arrangements and girder spacings. The new steel girder bridge design standards include one, two, three, and four-span bridges, with span lengths ranging from 150 ft to 300 ft, along with various girder spacings. The standards include flange and web plate sizes, stiffeners, cross-frame sizes, shear studs, and deck designs. LRFD Simon is a line-girder analysis and design program for steel I-shaped plate girders and allows users to quickly produce complete steel superstructure designs in accordance with the AASHTO LRFD Bridge Design Specifications. NSBA Splice allows a designer to quickly analyze various bolted field splice connections to determine the most efficient bolt quantity and configuration.
IBC 25-63: Cast Steel Connections in Steel Bridges
Jennifer Pazdon, Cast Connex Corporation, Toronto, ON Canada; Carlos de Oliveira, Cast Connex Corporation, Toronto, ON Canada
Extant case studies of cast steel structural connections in existing vehicular, rail, and pedestrian bridges will be examined to elucidate the advantages over conventional connection fabrication including structural performance (e.g. fatigue life increase), overall economy achieved through reduction in labor effort and complexity of fabrication and erection, accelerated construction, reduced lifecycle cost from enhanced longevity of coating systems and ease of inspection.
In the US, the use of project-specific engineered steel castings in the design and construction of steel bridges lags behind other economies.
Opportunities and challenges for increased adoption of project-specific engineered cast steel components in the US bridge market will be discussed including examination of a proposed framework of responsibility for component engineering design and casting manufacturing and resolution of discord in applicable codes and standards.
An overview of ongoing and anticipated future work of AASHTO/NSBA Task Group 17: Steel Castings to create resources to address identified challenges will be provided.
IBC 25-64: Horizontally Curved Steel I-Girder Bridge Cross-Frame Design Optimization and Specification Synthesis
Siang Zhou, the University of Texas Rio Grande Valley, Edinburg, TX; Oan Naqvi, the University of Texas Rio Grande Valley, Edinburg, TX
Cross-frames are important load-carrying members for horizontally curved steel I-girder bridges, inducing complex lateral bending behavior for construction and in-service loading conditions; however, they are often designed using standardized dimensions and layouts. This research synthesizes prior studies in the past two decades and current U.S. state transportation agency specifications to provide a holistic review of the state-of-the-art cross-frame design practices for horizontally curved steel I-girder bridges. Cross-frames are required to be designed as primary load-carrying members for horizontally curved steel I-girder bridges. Intermediate cross-frames are generally arranged radially to resist overall torsion of the bridge system, while cross-frames are often omitted in the vicinity of skewed bearing lines to assist uplift alleviation; the main difference among state specifications is regarding arrangements near supports. To advance cross-frame design for horizontally curved steel I-girder bridges for more optimized load distribution, numerical parametric studies are conducted to evaluate the effects of different cross-frame type and arrangement (such as alignment angle and spacing) on structural responses of these bridges, including girder flange lateral bending stress, girder movement (displacement and rotation), web out-of-plane buckling, and cross-frame stress. Bridges from the database of state transportation agencies and prior research are simulated in the parametric studies. Optimized cross-frame designs are proposed for single-span horizontally curved steel I-girder bridges (with or without support skew) to achieve a decrease in girder and cross-frame stress and a reduction in the amount of material usage for cross-frames, while maintaining stability requirements for the bridge system with complex geometry.
Analysis/Research/Design II
Time: 8:00-9:00 AM
IBC 25-65: I-65 over Kentucky St. and Brook St. – System Redundancy of Three-Grider Integral Steel Straddle Bents
Joshua Carter, AECOM, Louisville, KY; Charles Boltz, AECOM, Indianapolis, IN
The I-65 Bridge over Kentucky St. and Brook St. is a key component of the I-65 Central Corridor Project, which aims to replace or rehabilitate up to 18 bridges along the I-65 corridor in Louisville, Kentucky. The existing bridge is a multi-span steel structure featuring four Non-redundant Steel Tension Members (NSTM), in the form of steel cross girders, situated in a dense urban environment with low vertical clearance.
In collaboration with the designer, the Kentucky Transportation Cabinet (KYTC), and the contractor, a new three-girder steel straddle bent was selected to replace the existing NSTM cross girders with a redundant structure that meets the site’s geometric constraints. Although these straddle bents are typically employed in a stacked configuration—recognized by the Federal Highway Administration (FHWA) as load-path redundant—site-specific restrictions necessitated the use of an integral version of the straddle bent.
To ensure that the straddle bent qualifies as a System Redundant Member, a redundancy analysis was performed in accordance with AASHTO guidelines for the Analysis and Identification of Fracture Critical and System Redundant Members. This paper will detail the redundancy analysis and the benefits that the Kentucky Transportation Cabinet will derive from the improved structural integrity.
IBC 25-66: CIP Segmental Design of the Beaver River Bridge
Matthew Adams, H&H, Tallahassee, FL
The new Beaver River Bridges replace a single steel deck truss bridge on the Pennsylvania Turnpike, just north of Pittsburgh. The new bridges are parallel cast-in-place, balanced cantilever segmental structures, each 1645’ long. The boxes are typically 73’-4.5” wide, but the Eastbound structure flares to 89’-7” in Span 1. The structures cross the river in 5 spans, with a 240’ – 3 @ 385 ’- 250’ arrangement, and carry the turnpike over not only the Beaver River, but also over CSX and Norfolk Southern rail lines, as well as a local road. The piers vary from approximately 80’ to 188’ tall. They each have twin-wall columns for rotational stability and longitudinal flexibility. This presentation will discuss the designer’s approach to the bridge project, including both superstructure and substructure design, as the design of the substructure was particularly intricate.
The superstructure is cast monolithic with the piers in all cases. All piers are founded on 60” diameter drilled shafts, with 54” rock sockets. The geotechnical design required all drilled shaft forces be resisted by side friction, with no bearing assumption at the shaft tips. Pier 4, the shortest pier, carries a significant amount of the force from longitudinal loading, and is the critical element for the design. The twin-walls that crack under full temperature drop and full creep and shrinkage were iteratively studied using transformed properties to develop cracked moments of inertia used when those forces occur.
Movable Bridges
Time: 9:00 AM – 12:00 Noon
IBC 25-67: Multiple 52-hour Bridge Closures Eliminated with Strategic Workplanning
Zachary McKinley, PCL Construction Inc, Tampa, FL
The Benjamin Harrison Memorial Bridge, a vertical lift drawbridge over the James River near Richmond, Virginia, facilitates a crucial river crossing for 7,000 vehicles daily and permits ocean-going vessels to navigate upriver to the Port of Richmond, supporting local industries. Consequently, the bridge is regulated by federal regulation and must open on demand for vessels. Originally constructed in 1966 and reconstructed in 1977 following a bridge strike, the bridge was still operating with its original centering device supports and span lock. In recent years, however, the span locks had become increasingly unreliable, and the machinery frame supporting the span lock and centering device had suffered significant section loss. In 2023, the Virginia Department of Transportation (VDOT) planned a comprehensive overhaul of the span lock machinery and electrical tie-ins on both the north and south piers. The project was executed through a traditional design-bid-build process and was scheduled to involve two 52-hour full bridge closures, during which the span would be held in the fully raised position to avoid a maritime outage. This necessitated a 1-hour detour for the traveling public. During initial work planning, PCL determined it was feasible to eliminate the detour by implementing a 30-minute notification requirement for bridge openings and utilizing traffic flagging operations. This paper will explore the challenges surmounted during project planning to ensure the continuous operability of this vital infrastructure, with special emphasis on meticulous workplans, value engineering proposals, coordination for long-lead items, and measures to ensure safety and quality throughout throughout the project.
IBC 25-68: CSX Chickasaw Creek Swing Bridge Rehabilitation and Automation
Ryan Sullivan, PCL Civil Constructors, Tampa, FL; Taylor Miller, PCL Civil Constructors, Tampa, FL
Located in Mobile, Alabama, and spanning the mouth of the Chickasaw Creek, CSX Transportation’s Chickasaw Creek Bridge is a nearly 100-year-old through truss swing bridge. The bridge experiences the highest combined rail and marine traffic in CSX’s Gulf Coast Region. PCL Construction was engaged to perform upgrades as part of CSX’s ongoing program to implement bridge control systems and remote operations centers that allow CSX bridge operators to control multiple movable bridges from a centralized control center. PCL has a successful history of working with CSX, completing over fifteen movable bridge automation projects and three separate remote-control centers. The project scope for the Chickasaw Creek Bridge project included replacing the bridge’s electrical system, including the submarine cable, installing a new remote-control system, improving structural access, making structural steel repairs, and replacing all mechanical operating systems from hydraulic driven to electromechanically driven.
Chickasaw Creek, which feeds into the Mobile River, is vital for marine transportation, requiring five-seven bridge openings a day for marine traffic. Chickasaw Creek Bridge is also crucial for rail transportation, with a minimum of five trains crossing a day. The bridge is also located close to a rail yard, further increasing rail traffic and HDR Engineering were contracted with the understanding that the bridge and Chickasaw Creek waterway would remain fully operational throughout the construction. This required extensive preconstruction planning and effective design to ensure uninterrupted rail traffic and 24-hour operation of the bridge.
IBC 25-69: Design of the Belden Bly Bascule Bridge
William Goulet, STV Incorporated, Boston, MA
The Belden Bly Bridge, a heel-trunnion bascule bridge with an overhead counterweight, connects Lynn and Saugus, Massachusetts. Owned by MassDOT, the bridge will soon open to traffic following the operational testing phase. It accommodates two lanes of traffic in each direction, with bike lanes and sidewalks on each side. The bascule span is 77 feet long by 78 feet wide and crosses a 50-foot-wide channel that serves a fishing and pleasure craft community on the Saugus River, located upstream from the bridge. The project also includes approach spans on either side, retaining walls, and intersection improvements at the southern end of the project. The bridge profile was raised as much as possible to address local flooding issues.
The wide span and low water clearance posed significant design challenges, leading to the decision to place the machinery room above the roadway. As the bridge operates, the counterweight and movable span fold around the machinery room utilizing a four-link arrangement. This made it difficult to position the counterweight’s center of gravity without interfering with the machinery room. Throughout the design process, careful attention was given to maintaining overall balance and to avoid conflicts between bridge components through the full range of movement and put an emphasis on component detailing. Additionally, the width of the span was a controlling factor for the design of the machinery tower as deflections had to be minimized to maintain machinery alignment.
IBC 25-70: Renfrew Bridge – Glasgow’s First Double Swing
Amanda Ruyack, H&H, New York, NY; Barry Keung, H&H, New York, NY
This paper presents the design and construction of a new movable bridge in Glasgow, Scotland. The 184-meter double-leaf cable-stayed swing bridge features an asymmetric or “bobtail” arrangement with 65-meter forward spans and 27-meter back spans, actuated by a slewing bearing with a planetary gearbox arrangement. While the motion is simple, the mechanism to both operate and support the span in all conditions requires consideration of various load types, deformations, and thermal changes. In addition to being a complex indeterminate structure, the long span length presents many additional and unique challenges that were addressed by a focus on efficiency in both design and construction.
IBC 25-71: Unique Design and Construction of the Zaza River Bridge in Cuba
Jorge Suarez, P.E., STV, Inc., Pittsburgh, PA
The Zaza River Bridge in Las Villa, Cuba was built in 1959. This purpose of this project was to replace the existing steel truss bridge which was demolished by explosives by the revolutionary army lead by Fidel Castro to cut off a major supplies route to the Capital city of Havana. After coming into power, Castro needed the bridge to be replaced and proposed an international design-build competition for a replacement bridge. The winning proposal (designed by a 33-year-old engineer) would become the world’s first precast, prestressed (post-tensioned) concrete highway bridge erected without falsework by the progressive cantilever method. The main span was 300 feet.
This paper will present the bridge history and details, unique substructure and superstructure elements using post-tensioning bars. There was also a limitation on bridge element weight due to availability of crawler cranes to a maximum of 19 tons. AASHTO H20-16 loading was design criteria. Speed of construction was one of the most important factors in the bridge selection process.
The project only took 6 months to complete from date of award with unskilled labor, a 12-day worker’s strike and 20 days of inclement weather.
Digital Delivery
Time: 8:00-9:00 AM
IBC 25-72: Abingdon Road Bridge Redefined
Ted Januszka, P.E., Pennoni, Newark, DE; Nafiz Alqasem, P.E., Maryland Transportation Authority, Nottingham, MD
As part of the Maryland Transportation Authority’s (MDTA) $1.1 billion initiative to alleviate congestion and enhance mobility along the I-95 corridor, MDTA is reconstructing I-95 in Baltimore and Harford Counties, Maryland. Within this framework, Pennoni was engaged to design the replacement of the Abingdon Road Bridge, which spans I-95. Unlike other overpasses in the corridor, the Abingdon Road Bridge required phased construction to maintain continuous traffic flow along Abingdon Road throughout the project, rather than utilizing detours.
To meet this challenge, Pennoni employed advanced 3D Bridge Information Modeling (BIM) using OpenBridge Modeler, creating detailed models of both the existing and proposed structures. The new design features a two-span, haunched steel multi-girder bridge extending 280 feet. Integrating BIM with digital terrain models from adjacent projects enabled precise bridge sizing, optimization of vertical profiles, and a comprehensive assessment of alignment and grading impacts on the developing I-95 Northbound section. This modeling ensured sufficient vertical clearance over I-95 and facilitated the identification of potential conflicts or “clash detections” during construction staging.
The use of 3D BIM enhanced the constructability of the multi-phased design and effectively eliminated impacts to aerial and subsurface utilities, safeguarding critical infrastructure. Additionally, BIM fostered seamless communication with MDTA and Section 200 consultant teams, streamlining project coordination and accelerating design completion. Construction began in 2021 and was successfully completed in 2023. This project underscores the value of BIM in executing complex infrastructure projects with minimal disruption to the surrounding community.
IBC 25-73: PennDOT’s FIRST Digitally Delivered Bridge Project
Joshua Mies, EIT, Pennoni, Plains, PA; Robert Naugle, P.E., Pennoni, Plains, PA
Pennoni’s SR 3006 Section 250 (Milwaukee Road) over Gardener Creek project was selected to be PennDOT’s first Bridge Authoring Digital Delivery Pilot Project and became the first bridge in the state to be constructed entirely from a digital deliverable. All project information pertaining to the bridge structure, pavement structure and earthwork was provided in a digital format, 3D and 2D, with no structure plans or roadway cross sections. Pennoni was responsible for the preliminary engineering, final design, and construction consultation for the replacement of the existing 32’ long, single-span steel girder bridge with a steel grid deck carrying SR 3006 (Milwaukee Road) over Gardener Creek. The replacement structure is a 52’ long single-span, prestressed reinforced concrete spread box beam bridge on integral abutments. A 3D model, utilizing the OpenBridge Modeler software, was developed and refined to a level of detail that all information typically included in a plan set was provided through 3D views, attributes, annotated model-developed views and additional 2D details. Information was conveyed using saved views which automatically take the viewer to the desired information without the need to manipulate the model. This 3D model served as the contract document for bidding and construction.
Pennoni continued involvement throughout construction providing guidance and training on the model deliverables with the contractor. The structure was opened to traffic in June 2024, one month ahead of schedule.
Load Rating and Analysis
Time: 9:00 AM-12:00 PM
IBC 25-74: Erection Geometry of the Msikaba River Bridge
Heinrich van Wijk, AECOM, WA; David Middleton, Concor – Mota-Engil Joint Venture, Bedfordview, Gauteng, South Africa
The Msikaba River Bridge, poised to be Africa’s longest cable-stayed bridge, spans 580 meters over a 200-meter-deep gorge in South Africa’s Eastern Cape Province. It forms part of the National N2 highway, reducing travel time between East London and Durban while enhancing transportation safety and reducing costs. The bridge’s deck consists of two identical 290-meter halves supported by 127-meter-high pylons and 17 pairs of cables, anchored 130 meters behind each pylon. AECOM, appointed by the Concor – Mota-Engil Joint Venture, provided erection engineering services to ensure safe and precise construction of the bridge deck.
This paper explores the erection engineering methodology, focusing on the calculation of cable installation forces to maintain the deck and pylon geometry within the specified tolerances. The process involves employing finite element models in Midas Civil and SOFiSTiK for calibration and verification. The challenges of modeling complex construction stages, handling time-dependent effects, and implementing precise load management are addressed. Cable force calculation strategies, including displacement and force optimization, are investigated, and practical applications are discussed to ensure accurate control over the structure’s geometry throughout its erection.
IBC 25-75: The New AASHTO Risk-targeted Design Ground Motions
Thomas Murphy, Modjeski and Masters, Inc., Mechanicsburg, PA; Lee Marsh, WSP, Tacoma, WA; Ian Buckle, University of Nevada Reno, Reno, NV; Andrew Adams, Modjeski and Masters, Inc., Mechanicsburg, PA
The seismic design ground motions used in the AASHTO LRFD Guide Specifications for Seismic Design and the upcoming 10th edition of the LRFD Bridge Design Specifications have moved from a Uniform Hazard basis to Risk-targeted ground motions. Used in the building industry, Risk-targeted ground motions include consideration of the variation in the nature of seismic hazard across the nation. This paper will discuss the development of the Risk-targeted ground motions as adopted by AASHTO, the reasons behind their adoption, and how the change will impact the design of new bridges. The development of the target risk value, the assumed fragility curve, and how these affect the resulting design values will be addressed.
IBC 25-76: Load Rating Analysis of the Smithfield Street Bridge
Majid Eshraghi, University of Pittsburgh, Pittsburgh, PA; Piervincenzo Rizzo, University of Pittsburgh, Pittsburgh, PA
The load rating analysis of the Smithfield Street Bridge, an iconic lenticular truss bridge in Pittsburgh, Pennsylvania is performed using finite element modeling and Load and Resistance Factor and Allowable Stress rating methods. Built in 1883, this bridge has played a critical role in the region’s transportation infrastructure for over a century. To the best of the authors’ knowledge, the latest load rating analysis on this bridge was performed more than 20 years ago using Allowable Stress rating method and based on simplifications and conservative assumptions, which led to posting the bridge for 23 tons. In the study presented here, the load rating was performed using a detailed finite element model that takes into account the bridge’s unique design, material properties, and current conditions. Static analysis was then performed to calculate the forces developed due to the presence of PennDOT standard trucks. The results of the analysis showed that the controlling members of the bridge were different than the ones determined with the previous rating and the posting load could be increased significantly.
IBC 25-77: Aerodynamic performance of cable-supported bridges during retrofit operations
Pierre-Olivier Dallaire, RWDI, Guelph, ON, Canada; Guy Larose, RWDI, Guelph, ON, Canada; Erik Marble, RWDI, Guelph, ON, Canada; Zachary Taylor, RWDI, Guelph, ON, Canada
Several existing suspension bridges are going through important retrofit programs in an effort to extend their service life and to preserve their main cables. These retrofit programs include seismic upgrades, replacement of selected truss structural members, painting operations, addition of suicide deterrent fences and installation of cable dehumidification. Therefore, temporary works, platforms and encapsulation/tarping of the deck are often deployed to complete the structural upgrades while minimizing environmental impacts. These temporary structures are known to influence the sensitivity of the structure to wind-induced vibrations. One notable recent example is the observed vertical deck motions induced by vortex-induced oscillations on the Verrazano Narrows bridge in 2020 caused by the tarp installed around the deck. This event provided convincing evidence that this risk is real and cannot be overlooked by bridge designers.
Because of the transient nature of the structure during this work, a strategy combining experimental methods and numerical predictions was developed to evaluate bridge aerodynamic stability, the wind loads and to provide guidelines for construction schemes. In particular, limits of encapsulation can be defined to allow these retrofit works to be carried out without negatively affecting the perception of bridge users or the reliability of the structure performance. This strategy can also leverage forecasting capabilities to optimize the exposure time of the bridge under temporary works.
This presentation will draw experience, findings and conclusions from various bridge retrofit projects including the Golden Gate Bridge, the Forth Road Crossing, the Verrazano Narrows Bridge, the Robert F. KennedyBridge and the Kessock Bridge.
IBC 25-78: Seismic Analysis and Design of a Curved Overpass in Guayaquil, Ecuador
Pedro P. Rojas, Ph.D., ESPOL Polytechnic University, Guayaquil, Guayas, Ecuador; JOSÉ Barros, Ph.D., Catholic University of Santiago de Guayaquil, Guayaquil, Guayas, Ecuador; Joseph HERNÁNDEZ, MPM., Consultora-PRA Pedro Rojas & Asociados S.A., Guayaquil, Guayas, Ecuador
Guayaquil is one of the most important cities of Ecuador. It has several private and concessioned ports located at the south of the city. Some of the private ports are container ports and the main access road to them is narrow. This usually causes traffic jams during the ports rush hours. To solve this situation, a curved overpass was designed. This paper discusses the studies performed for the analysis and design of the curved overpass. The first part of the paper provides a brief review of the geometry and the materials considered for the overpass. The second part of the paper describes the field works executed at the beginning of the studies. The structural criteria and the three-dimensional elastic model developed for the analysis and design of the substructure and superstructure components of the overpass are described. It is concluded that the designed curved overpass satisfies the code requirements related to strength, stiffness, and ductility.
International Major Bridge Design and Construction
Time: 8:00 AM – 12:00 Noon
IBC 25-79: A New Approach to Rigidly Connect Two Dual Continuous Box Girder Bridges
Ruipeng Li, CCCC Second Highway Consultants Co Ltd, Wuhan, Hubei China
Zengjiang bridge is composed by a pair of dual bridges connecting Guangzhou and Huizhou in Guangdong province in China. The bridge needs to be widened by connecting the dual portions longitudinally to allow for an additional traffic lane. The traditional method of rigidly connecting dual bridges transversely involves of partially cutting and then jointing the bridge overhang portions into one bay, and subsequently installing diaphragms in the new bay. Such method not only significantly complicates the Zengjiang bridge reconstruction work due to drilling holes into box girder webs and installing forms below the bridge overhangs for the diaphragm construction, but could also damage the bridge structure since the bridge was constructed segmentally and prestressing tendons were jacked between overhang ends for each segment.
In this paper, a new method is proposed to rigidly connect the dual continuous box girder bridges, which overcomes the aforementioned drawbacks of the traditional method. Vertical holes are drilled into the bridge deck at a specified spacing which avoid the conflicts with the transverse prestressing tendons. The drilled holes are then installed with hooks and grouted by high strength cement. A new concrete deck is poured on top of the original dual bridge decks so that a composite section is formed among the new deck and the original box girders. Diaphragms are not required for the new composite section. Therefore, the proposed method significantly simplifies the bridge reconstruction work and shortens the reconstruction phase, and minimizes any potential structural damage to the original bridge.
IBC 25-80: Incremental Launching of 256m Steel Box Girder Bridge on QEW highway over Credit River in Ontario
Hyunwoo Kim, P.Eng., AECOM, Pickering, ON Canada; Jovan Vukotic, P.Eng., AECOM, Thornhill, ON Canada; Firooz Panah, P.E., AECOM,Boston, MA; Damien Keogh, P.Eng., AECOM, Mississauga, ON, Canada
This paper discusses the design and construction of a twinned steel box girder bridge alongside 120 years old heritage concrete open-spandrel arch bridge, spanning an environmentally sensitive Credit River on major QEW highway in Ontario. No piers were allowed in water. The steel box girders 254 m long were incrementally launched over 3 spans without the need for intermediate supports in the river and construction within the river. Four steel boxes are used to support 26.7 m wide bridge deck. Girders were assembled and launched from the east riverbank without impacting riverbed or aquatic life, in full compliance with environmental regulations. Key design elements included optimizing the girder’s load distribution, ensuring structural stability during launching, and addressing construction forces induced by incremental movement. The paper will also cover analytical efforts and the design of the foundations, piers, and deck. Also, a brief explanation of the process leading to the selection of the steel box girders for the superstructure. Advanced simulations and planning were used to coordinate the construction and ensure minimal disruption to traffic on the existing bridge. High esthetic appearance of modern bridge is achieved complementing the adjacent graceful and historic arch structure.
IBC 25-81: Two Landmark Cable Stayed Bridges for Active Transport in Perth
Wolfram Schwarz, WSP, Perth, WA Australia; Gerhard du Plessis, private, Caulfield North, VIC Australia; Risto Kiviluoma, WSP, Helsinki, Finland
The Causeway Pedestrian and Cyclist Bridges Project in Australia delivers a landmark active transport connection across the Swan River in Perth, Western Australia.
Consisting of two cable stayed bridges, the constructed option limited the number of river piers to just three, acknowledging the spiritual and cultural importance of the Swan River (Derbal Yerrigan) to Perth’s first nations peoples.
Point Fraser Bridge comprises a single 52 m high pylon representing a boomerang. The bridge is asymmetric with a 48 m side span and a 99.7 m main span supported by cables attached to the inner side of continuously curved bridge deck.
McCallum Park Bridge comprises two 46 m high pylons representing digging sticks. The bridge is symmetric with 60 m side spans and a 155 m center span supported by cables attached to the inner side of the S-shaped bridge deck.
The basis of design included an ambitious requirement of a minimum 6.0 m wide deck with single sided cable attachment points to allow for a 2.5 m wide pedestrian path and a 3.5 m cyclist path. The superstructures and pylons of the bridges are manufactured from 400 grade weathering steel. The comfort criteria for footfall excitation on the project was defined for high density pedestrian traffic and joggers to be able to host annual marathon events.
This paper discusses the construction staging, cable force finding, camber prediction and geometry control as well as the footfall and wind dynamics of the lightweight steel structures.
IBC 25-82: Design and Construction of Macau Bridge
Si dong Li, TYLin, Chongqing, Liangjiang New Area China; Yu Deng, TYLin China; Ya ping Lai, TYLin, China; Xiao hu Chen, TYLin, China
The Macau Bridge is the fourth maritime connection between Macau and Taipa, effectively linking reclamation areas A and E in Macau’s new urban district to the artificial island at the Hong Kong-Zhuhai-Macau Bridge port. Spanning 3,085 meters, the bridge accommodates two-way traffic across eight lanes, including dedicated motorcycle lanes in the center. This bridge comprises two main spans, each 280 meters long, crossing the Outer Harbour Channel and Macau Waterway. To address strict requirements such as navigational clearance and aviation restrictions, a steel truss bridge design was adopted. Innovatively, the steel trusses are positioned within the central roadway rather than alongside the main girder and are angled inward by eight degrees. These trusses are connected by crossbeams at the top, forming a novel steel truss-box girder composite structure. This design concentrates structural forces within the core areas of the steel box girder and truss, enhancing the overall structural efficiency. Compared to traditional steel truss bridges, the Macau Bridge offers improved lateral stability, an appealing aesthetic, optimized material usage, and significant economic benefits. This paper discusses the key design considerations, construction methods, load capacity testing and the effect of the bridge upon completion. The innovative structural solutions implemented in the Macau Bridge demonstrate advanced engineering practices and provide valuable insights for future bridge projects.
IBC 25-83: The new Pattullo Bridge in Vancouver, B.C.
Martin Romberg, Leonhardt, Andrä und Partner, Stuttgart, Germany; Peter Walser, Leonhardt, Andrä und Partner, Stuttgart; Victor Alvado, Leonhardt, Andrä und Partner, Stuttgart
The Pattullo Bridge, a crucial connector over the Fraser River in British Columbia since its opening in 1937, exhibits significant structural deterioration, necessitating the construction of a new bridge. This paper outlines the design and construction features of the new Pattullo Bridge, emphasizing its seismic isolation system utilizing Lead Rubber Bearings and the corresponding calculation methods. Spanning a total length of 1235 meters, the bridge consists of a cable-stayed main section measuring 770 meters and two approach viaducts with length of 770 meters and 465 meters. The cable-stayed section includes a 332-meter main span, complemented by compensating spans of 162 meters and 84 meters, and offers a maritime clearance of 47 meters. A single 167-meter high double H-shaped pylon, constructed from reinforced concrete with post-tensioned cross-beams, supports the cable-stayed span. The composite deck features a steel grillage made of high-strength weathering steel beams, topped with full-depth precast concrete panels connected by in-situ concrete joints. The construction employs a free-cantilever method for the cable-stayed span and the initial compensation span, while the remainder utilizes temporary supports. This innovative design not only addresses current capacity and safety concerns but also ensures resilience against seismic events, marking a significant advancement in bridge engineering in the region.
IBC 25-84: Design and Construction of the New Storstrom Bridge
Peter Curran, Ramboll, London, United Kingdom; Luca Cargnino, Ramboll, Copenhagen Denmark; Martin Svendsen, Ramboll, Copenhagen, Denmark
The existing Storstrøm Bridge is an historic combined rail and road bridge, opened in 1937 and was then the longest road bridge in the Europe. Significant maintenance activities on rehabilitation of the existing bridge have taken place over the last 30 years. The condition of the existing structure and the ongoing maintenance demands are such that replacement is now economically advantageous. This is further motivated by the limitation of just one railway track on the existing bridge, which is insufficient to support the development of the strategic railway corridor between Copenhagen and Hamburg.
The new replacement Storstrøm Bridge will be Denmark’s third largest after the Øresund Bridge and the Great Belt Bridge. It will be approximately 4 km long and have electrified double rail tracks accommodating speeds up to 200 km/h and a two-lane road. The bridge is presently under construction and is expected to be opened in October 2025.
The paper will describe the design approach adopted which was wholly driven by the contractors chosen construction methodology for the structure and which has involved pre-casting all elements piece large in purpose built fabrication sheds and transporting into position. The paper will provide an update on the progress of construction including the cable stayed spans which form a focal point for the crossing and outline the design challenges and opportunities that have been encountered. The paper will outline the approach to ship collision including in-service runability analysis and the associated outcomes.
IBC 25-85: Lifecycle Management and Sustainable Decommissioning of the Existing Storstrøm Bridge
Jan Vig Pilegaard, Rambøll Danmark A/S, Copenhagen S, Denmark; Claus Pedersen, Rambøll Danmark A/S, Copenhagen S Denmark; Jørgen Højris Jensen, Rambøll Danmark A/S, Copenhagen S, Denmark; Mette Elbæk Andersen, Rambøll Danmark A/S, Copenhagen S, Denmark; Mette Thyregod, Rambøll Danmark A/S, Copenhagen S, Denmark
The existing Storstrøm Bridge spans 3,500 yards, connecting the islands of Falster and Masnedø in Denmark and serving as a vital rail and road link. Inaugurated in 1937, it was then the longest road bridge in Europe. Consisting of 47 steel spans with plate-girder beams supported by a Gerber girder design with semi-suspended spans and three central arch spans, the bridge has undergone extensive maintenance but now requires decommissioning and replacement as it reaches the end of its lifespan. A comprehensive strategy for maintenance, rehabilitation, and demolition has been developed to manage this transition effectively.
This contribution outlines the technical methods used to extend the bridge’s service life, including detailed inspections and reliability-based analysis to assess the performance of concrete and steel components like the main steel girder and cross beams. Load testing and condition assessments of the concrete deck informed targeted repairs, while fatigue crack management and corrosion protection, including riveted connection reinforcement, were essential measures for steel components.
Focus is given to emergency repairs on critical elements, such as the riveted corbels in the semi-suspended spans, where major cracks were identified. A novel strengthening solution was implemented rapidly, allowing rail traffic to resume, supported by advanced monitoring with strain gauges on 184 corbels for crack/stress tracking.
The demolition strategy prioritizes sustainability and safety, involving controlled cutting and blasting techniques with evaluations of CO₂ emissions, waste management, and structural stability. The demolition aims to meet BREEAM Infrastructure certification, factoring in climate impact, recycling, and biodiversity.