Engineers' Society of Western Pennsylvania

Location

337 Fourth Avenue
Pittsburgh, PA 15222

Phone: (412) 261-0710 Email: eswp@eswp.com Get Directions

Tuesday, July 15, 2025

Technical Sessions

Accelerated Bridge Construction

Time: 8:00 – 10:00 AM

IBC 25-07: Leveraging ABC Techniques for Weekend Bridge Replacements: A Case Study in Traffic Management and Efficiency
Joseph Tierney, TranSystems, Boston, MA

Replacing critical transportation infrastructure in high-traffic corridors poses significant challenges due to potential economic and social impacts.This summary highlights a successful accelerated bridge construction (ABC) project that replaced two bridges carrying 135,810 vehicles daily across two weekends, ensuring uninterrupted traffic flow by alternating closures between the two bridges. Key techniques included relocating overhead electrical lines, using a zipper barrier for a median crossover, and deploying precast elements such as abutment caps, moment slabs, and bridge units. The team also performed wingwall rehabilitation and concrete closure pours to enhance durability.

Strategic planning and collaboration were essential to success. A comprehensive risk assessment helped anticipate challenges, while detailed construction schedules and traffic management plans minimized disruptions. Public outreach efforts kept residents informed, including flyers, stakeholder coordination, virtual meetings, and real-time messaging boards. Each weekend closure (8:00 PM Friday to 4:00 AM Monday) allowed one bridge to close while the other managed two-way traffic. This ensured the safe removal and installation of new bridge components, including waterproofing and paving. The four weeks between closures were used for tasks like installing cast-in-place barriers and preparing for the next phase.

The project leveraged innovative solutions, such as the zipper barrier system for traffic control, to enhance safety and efficiency. Early collaboration, stakeholder engagement, and ABC methodologies proved critical in minimizing disruptions and meeting tight deadlines.This case study provides valuable insights for transportation agencies. It demonstrates that ABC techniques can successfully address urban infrastructure challenges while maintaining traffic flow and reducing construction timelines.

IBC 25-08: Accelerated bridge construction including helical pile for a railroad truss replacement in an urban environment
Allen Smith, P.E., Crawford, Murphy and Tilly, Saint Louis, MO; Jared Wigger, P.E., crawford, murphy and tilly, Saint Louis, MO

TRRA’s “Broadway Truss Replacement Design Build” located in downtown St. Louis presented many challenges. The existing MacArthur Bridge is over 120 years old, located in an urban environment, and on a highly traveled rail corridor. The existing railroad span was a 150’ double track, through truss over three lanes of a busy street. While one track was supported fully by two railroad truss lines, the other track was supported by both a railroad truss, and an abandoned highway truss. Condition and geometry constrictions necessitated the span replacement. The design-build team was tasked with replacing the bridge spans while maintaining single track service with minimal double track outages.

This paper will explore the difficulties and solutions associated with replacing this open-deck truss span with a ballast deck girder span in a constrained, urban work setting. The complex framing of the bridge required creative solutions for the removal and demolition. SPMTs were used to remove existing trusses and move in the new spans. Temporary girders were used to support the existing center span. Lastly, a contractor innovation was the use of freight containers to support the new girder span assembly.

Helical piles were used as a unique low overhead foundation solution. This is the first known use of these piles to support a rail bridge. Lessons learned in using a foundation with limited existing design standards will be presented. Other topics to be explored will be the issues associated with connecting the new, heavier structure to the existing bridge.

IBC 25-09: Sonoma Marin Area Rail Transit – Precast Bridge 16.86 over San Rafael Creek (San Rafael, CA)
Brian Olp, STV, Denver, CO

Sonoma Marin Area Rail Transit (SMART) is a commuter rail line between San Rafael, CA and Santa Rosa, CA. As part of a proposed two-mile southern expansion from San Rafael to Larkspur, the rail line crosses San Rafael Creek just south of San Rafael Downtown Station and 2nd street. Two single track, single span structures were proposed to carry the railroad over the creek. STV (Designer) and Stacy-Witbeck/Herzog JV (Design Builder) worked with the agency to develop a unique design solution for these rail structures to solve the site constructability, geometric, and environmental issues.
A concrete trough bridge section consisting of precast, pre-stresssed elements connected by post-tensioning was developed which achieved the required low structure depth. This design section simulated a cast-in-place section but utilized high quality precast elements.
To meet the aggressive schedule, the proposed precast element solution avoided the need for cast-in-place concrete and any falsework required within the channel, which was restricted due to the environmental permit.
The brackish water at this tidal inlet location created a very corrosive site condition for all the bridge elements. This was mitigated by use of epoxy coated rebar, increased concrete cover and special corrosive resistant concrete mixes to achieve the desired 100-year design life.
The contractor leveraged the precast bridge concept to stay out the channel and accelerate the construction schedule during the limited build window. The construction utilized special temporary support brackets on the precast girders along with timber struts to build the structure, which required no traditional falsework.

IBC 25-10: Repairs to the Historic Tombigee River Hwy 182 Bridge
Joe Knapp, Genesis Structures, Kansas City, MO; Randy Boudreaux, Neel-Schaffer, Jackson, MS; Steven Bowen, Malouf Construction, Greenville, MS

The historic Tombigbee River Bridge in Columbus, Mississippi, has encountered numerous challenges throughout its nearly 100-year history. In February 2020, a runaway barge struck the eastern river pier, displacing it by nearly 12 inches and jeopardizing the two supported truss spans.
Neel-Schaffer Engineering and Malouf Construction collaborated to devise an innovative method to temporarily support the precariously positioned bridge spans, enabling the removal of the damaged pier and the construction of a new one. The new permanent piers were constructed directly upstream and downstream of the existing pier, designed to accommodate an overhead gantry system to support the two spans. Once the spans were supported by the gantry system, the existing pier was demolished. A precast footing and riser were then floated into position between the gantry legs and onto the new piers. This paper and presentation will delve into the unique history of the Tombigbee Bridge, previous repairs conducted by the same engineering and construction team, and the design and execution of the latest repairs.

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Bridge Rehabilitation

Time: 8:00 – 10:00 AM

IBC 25-11: Increasing Interstate Vertical Clearances in an Urban Environment
Scott Fisher, Virginia DOT, Colonial Heights, VA; Eric Thornton, Virginia DOT, Colonial Heights, VA

The Richmond Bridge Rehabilitation Bundle includes five VDOT owned bridges over I-95 in the City of Richmond: 1st Street Bridge, 4th Street Bridge, 5th Street Bridge, 7th Street Bridge, and Broad Street Bridge. These five bridges were designated as structurally deficient.

The original structures had been plagued with vehicle strikes as the vertical clearance on all five structures was sub-standard (averaging ~14’- 5”). The scope of the project was to increase the vertical clearance to a minimum of 15’-0”, close the joints, and rehabilitate the substructures. The Design-Builder was able to use innovative techniques and increase the vertical clearance on all bridges a minimum of nearly 16’-0” and in some cases up to 17’-4”.

This was an extremely challenging project due to the heavy traffic flow in the I-95 corridor, multiple major utilities that needed to be suspended (and kept in service) over the interstate during the phased demolition and construction of the superstructure, and the urban constraints that would not physically permit extensive roadway bridge-approach work.

Four of the bridges were able to be reconstructed using conventional phased bridge replacement techniques (while suspending the existing electrical conduits). The Broad Street Bridge was reconstructed with Accelerated Bridge Construction techniques over the course of 4 weekends. ABC techniques were chosen to minimize the disruption to the City of Richmond’s busiest roadway and minimize impacts to the Virginia Commonwealth University (VCU) hospital/emergency room.

IBC 25-12: Crawford Avenue Bridge Rehabilitation – They don’t make them like they used to and that’s okay.
Matt Pierce, P.E., Benesch, Cranberry Township, PA; Jason Lewis, P.E., Benesch, Cranberry Township, PA

The Crawford Avenue Bridge carries PA 711 over the Youghiogheny River and CSX railroad, and is a focal point for residents, commerce, and recreational users within downtown Connellsville, PA. Constructed in 1959, the existing six-span steel superstructure used conventional pin and hanger details at four locations supported by rocker bearings on lightly reinforced concrete gravity substructures. The project scope of work included a superstructure replacement to eliminate the pin and hangers, a reduction of the existing seven deck joints, bearing replacements, and improved multimodal function for vehicles, pedestrians, and cyclists. Design challenges included: deck typical section and barrier type selection for multimodal use with stakeholder involvement; unbalanced span arrangement for continuous steel beam design resulting in uplift conditions, non-standard bearing designs, and unusual deck pour sequencing; and strut-and-tie modeling of deep concrete pier caps. Design solutions included using several unusual non-standard details such as the Rutgers Barrier, installing a deadman system to provide fixity at an abutment, and using sliding plate elastomeric bearings to accommodate both a 490’ expansion length and uplift. Construction proved equally challenging with river flooding at near record levels, locating and avoiding existing reinforcement, steel erection and fit up given difficult vertical geometry, temporary utility support, barrier construction, and discovering historic bridge anchorages. This presentation will review the challenges, solutions, and lessons learned to improve the Crawford Avenue Bridge while demonstrating that they don’t make them like they used to and that’s okay!

IBC 25-13: Deck Replacement of portions of the Eastbound William Preston Lane, Jr. Memorial (Chesapeake Bay) Bridge
Tekeste Amare, Maryland Transportation Authority, Baltimore, MD; Philip Waldvogel, WSP, Edgewood, MD; David Marcic, Hardesty & Hanover, Annapolis, MD; Scott Eshenaur, Modjeski and Masters, Mechanicsburg, PA

The Maryland Transportation Authority (MDTA), as part of a continuous effort to preserve the condition and working order of the William Preston Lane, Jr. Memorial (Chesapeake Bay) Bridge, has engaged in Phase 1 of a multi-phased deck rehabilitation program at the four-mile long two-lane Eastbound Bay Bridge, which was opened to traffic in 1952 with prior deck rehabilitation works in 1973 and 1986. A Construction Manager at Risk (CMAR) project delivery method was selected by MDTA to include the Contracting Team in this complex project from design through construction completion. The scope of work includes removal of existing concrete deck and floor system as 30-foot units, called panels; installation of new prefabricated deck panels comprised of Exodermic™ deck, composite stringers and floorbeams; strengthening of selected truss members and gusset plates; new bearing installations; and utility relocations. The new prefabricated deck panels are four feet wider than the existing deck and include MASH TL-4 barriers. Specially designed link-slabs make the deck continuous between new prefabricated deck panels. Working with consultant designers and the Contractor to utilize available nighttime lane closure windows, a method to replace deck panels overnight was implemented. The Contractor’s means and methods include the use of marine construction and large barge mounted cranes to prepare before lanes are closed to traffic, allowing efficient use of available windows. This approach prioritized reduction of impacts to the traveling public while maximizing efficiency of construction progress, all while working from the water on deck elevations ranging from 90 to 180 feet.

IBC 25-14: Underwater Concrete Repairs on the Eastbound William Preston Lane, Jr. Memorial (Chesapeake Bay) Bridge
Ruel Sabellano, Maryland Transportation Authority, Baltimore, MD; Scott Nugent, Marine Solutions Incorporated, Rosedale, MD; Gregory Desing, Pennoni, Virginia Beach, VA

The Maryland Transportation Authority (MDTA) utilizes a comprehensive underwater inspections every four years on bridges with substructures in water. Following underwater inspections at the Eastbound William Preston Lane, Jr. Memorial (Chesapeake Bay) Bridge, areas of exposed steel reinforcing and concrete spalling were reported on two isolated locations. Due to the specialized nature of the underwater concrete repairs, including working at depths up to 75 feet below water level, MDTA utilized two AE firms with specialized engineering and commercial diving capabilities. Marine Solutions performed underwater concrete repairs and Pennoni performed underwater construction inspection of the repairs.
The approach to performing these challenging underwater repairs involved locating and assessing the current conditions warranting repair, cleaning the areas by 4k psi water pressure to remove marine growth and loose concrete, installation of steel stay in place forms attached by concrete anchors along edges, sealing of form edges and pumping of grout. Grout was pumped from the lowest ports to the highest ports, ensuring the forms are completely filled with grout, all while continuously monitoring for leaks. Utilizing separate diving equipment to perform construction inspection, Pennoni verified each step of the construction process before moving forward. Monitoring and maintaining proper slump and water mix ratio of the grout was a critical factor to ensure proper water displacement.

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Bridge Inspection and Evaluation Session

Time: 8:00 – 10:00 AM

IBC 25-15: Navigating FHWA Approval Process for System- or Internally-Redundant Members
Justin Ocel, Federal Highway Adminstration, Baltimore, MD

The 2022 update to the National Bridge Inspection Standards (NBIS) introduced new terms into the lexicon of bridge inspection, these being nonredundant steel tension members (NSTMs), system redundant members (SRMs), and internally redundant members (IRMs). The concept of NSTM was not new, this was a new name for steel members in tension which require arms-length in-service inspection every 24 months. NSTMs are members lacking load path redundancy, identified by counting the number of independent load paths between points of support. If an Owner can demonstrate that an NSTM has viable alternate load paths via rigorous structural analysis then the member could be deemed an SRM, and if they can prove that build-up members with fractured components can remain serviceable for an inspection cycle, then it may be deemed IRM. The benefit of SRM or IRM designations is they do not carry the burden of strict, arms-length hands-on, 24-month inspection intervals. The Federal Highway Administration (FHWA) must approve the procedures Owners use to classify and inspect SRMs or IRMs. This presentation will cover the process Owners and FHWA must follow to classify steel bridge members as SRM or IRM. There have been a limited number of Owners that have approved procedures for SRM or IRM classification and a summary of those specific procedures will also be covered.

IBC 25-16: The Right Tool for the Job: A Look at TxDOT’s Bridge Inspection Program
Bob Pearson, Texas DOT, Austin, TX

The Texas Department of Transportation (TxDOT) has long been committed to ensuring the safety and integrity of the state’s bridge infrastructure. In pursuit of this mission, TxDOT has developed a comprehensive bridge inspection program that leverages the right tools and methodologies to create and maintain high standards of quality and accuracy. This abstract provides an overview of the key components of TxDOT’s bridge inspection program, highlighting the use of consultant inspections, in-house reports, quality control measures, advanced data visualization, and cutting-edge technologies.

Some of the “Tools of the Trade” (implemented and planned):

Consultant Inspections (Routine, NSTM, Underwater, etc.)
In-house Maintenance Inspections
Bridge Inspection Follow Up Actions
Quality Control on Inspection Reports
Data Visualization (of Maintenance needs, Scour Critical Bridges, Load Rating Documentation, etc.) with Tableau Dashboards
API Integration for Highway Feature Information (planned)
sUAS Drone Inspections (planned)
Front-end Error Check of Data
Back-end Validation of Element Values (planned)
Quality Assurance of Inspection Program

By using all of these tools in conjunction, we are able to manage the inspection of the 57,000+ bridges we are tasked to inspect and submit to the FHWA.

IBC 25-17: Norfolk Portsmouth Beltline – Emergency Response
Howard Swanson, Hardesty and Hanover, Atlanta, GA; Charlie Graning, PCL Construction Inc, Tampa, FL

What happens when an unstoppable force meets an immovable object? This paradox, often referenced in science classes, unfolded in real life in 2024. On a bright, clear late-spring day, a tugboat heading north on the Elizabeth River near Portsmouth, VA, collided with the Norfolk Portsmouth Beltline Railway bridge, which spans a navigable channel. The impact shifted the stationary 180’ long through-truss on the west end by more than 6.5 feet and twisting one of the tower legs supporting the 384’ vertical lift bridge suspended 195’ above the crucial waterway. This paper recounts the aftermath of this collision and the collaborative efforts of the owner, engineer, and contractor to assess, stabilize, and restore the bridge and rail line.

IBC 25-18: Machine Learning-Assisted Visual Assessment of Reinforced Concrete Bridges in Namibia
Nokuphila Dlamini, University of Namibia, Ongwediva, Oshana Namibia; Philemon Arito, University of Namibia, Oshana Namibia

Defect detection is essential for maintaining the durability, service life and safety of reinforced concrete (RC) bridges. The rising number of ageing bridges and the corresponding costs associated with their maintenance and repair has driven the growing interest in structural diagnostics technology. Traditional bridge inspection methods such as visual inspection are labour-intensive, subjective and time consuming. Visual inspection of bridge components in constricted spaces is also risky. The use of Artificial Intelligence (AI) tools such as Convolutional Neural Networks (CNNs) can improve the accuracy and reliability of bridge condition assessment while simultaneously overcoming the aforementioned challenges of visual inspection. CNNs, for example, can recognise and differentiate common bridge defects such as cracks, corrosion stains, efflorescence and spalling easily and with minimum human supervision and errors. This paper proposes the use of Convolutional Neural Networks (CNNs) as an automated defect detection tool possessing enhanced accuracy and efficiency for RC bridges in Namibia. The application of CNNs in the visual assessment of a deteriorating RC bridge in Namibia has been presented. Aspects such as data preprocessing, training methods and performance metrics have also been investigated. Advancements such as CNNs signify a shift towards safer, faster, reliable and more cost-effective approaches in condition assessment of RC bridges.

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Pedestrian

Time: 8:00 – 10:00 AM

IBC 25-19: ESCR Tied Arch Pedestrian Bridges
Silvio Garcia, Hardesty & Hanover, LLC, New York, NY; Kevin Lee, Hardesty & Hanover, LLC, New York, NY

Ongoing climate change has resulted in rising sea levels and more severe coastal storms. The East Side Coastal Resiliency (ESCR) project seeks to improve the overall climate resiliency of local properties, businesses, schools, and critical infrastructure and to protect local residents from the threats of future storm surges and flooding. Part of a larger plan for a comprehensive coastal protection system around the entirety of lower Manhattan, the project entails the construction of an integrated flood protection system consisting of raised parkland, floodwalls, floodgates, and storm drainage infrastructure improvements.

H&H played a leading role in the design of two new steel tied arch pedestrian bridges, the 209 feet long Delancey Street Bridge and 151 feet long E10th Street Bridge, over the FDR Drive and their associated accessible approach structures which connect the new raised parkland along the waterfront to the existing upland residential communities. Our comprehensive professional engineering services encompassed conceptual, preliminary, and final design and construction support for the bridge replacements, which were constructed using Accelerated Bridge Construction (ABC) techniques using self-propelled modular transporters.

The project posed a unique engineering challenge and setting for bridge design and construction as the need for the new bridges stemmed directly from an environmental context. The two bridges were envisioned to be signature structures that complemented the overall aesthetic of the surrounding neighborhood and parkland, reflecting the architect’s vision of lightness and modernity in the bridge geometry and profile while achieving a harmonious blend of functionality and elegance.

IBC 25-20: Schuylkill River Trail Cable-Stayed Pedestrian Bridge
Trevor Kirkpatrick, AECOM, Tampa, FL; Joel Cummings, AECOM, Philadelphia, PA; Keith Lee, AECOM, Sacramento, CA; Nick Green, AECOM, Tampa, FL; Bob Anderson, AECOM, Tampa, FL

The Schuylkill River waterfront in Philadelphia south of the Fairmount Water Works, once an industrial hub, had fallen into neglect by the mid-20th century. In 1992, the non-profit Schuylkill River Development Council (now The Schuylkill River Development Corporation (SRDC)) began fundraising for a riverfront trail and park. The City of Philadelphia, SRDC, federal, state, and private partners, have invested over $94 million, leading to significant improvements in the built environment and neighborhood revitalization along the completed sections of trail and greenway.
The latest addition is a half-mile trail featuring a stunning 600-foot cable-stayed bridge with a graceful “S-curve” horizontal alignment. The twin towers, rising 139 feet above the deck, each anchor 28 wire rope cables. These cables hold up curved, precast, post-tensioned concrete U-beams and a 25-foot-wide bridge deck with circular overlooks at each tower, offering magnificent views of the river and city skyline. The deck is hinged at mid-span to mitigate post-tensioning losses. Tuned mass dampers were installed inside the U-beam to minimize vibrations and improve pedestrian comfort. Each tower is founded on nine 6-foot diameter drilled shafts to resist gravity, vessel collision and ice loads. Above the deck, the towers taper in two directions, adding dimensional interest. The cables are arranged in a unique basketweave pattern and use elegant pin-and-clevis anchors for a streamlined look. Aesthetic lighting and pedestrian benches enhance the user experience. The design focuses on conventional construction methods and minimizing future maintenance while providing an architecturally sensitive solution that reflects the spirit of Philadelphia.

IBC 25-21: Integrated Construction Methods of Cable-Stay Pedestrian Bridges
Matthew Cardamone, PKF Mark III Inc., Newtown, PA; Stephen Carullo, PKF-Mark III

The Schuylkill River waterfront in Philadelphia has been revitalized with the construction of the Christian Crescent Main Span, an iconic 3-span concrete cable-stayed pedestrian bridge with a 600-foot “S-curve” alignment. PKF’s segment of the trail spans nearly 3,000 linear feet, providing an off-road connection between Fairmount Water Works and Bartram’s Garden, two National Historic Landmarks. The bridge’s structure rests on caisson foundations composed of 18 six-foot diameter shafts, each permanently cased two feet into bedrock with variable-length rock sockets. The scale of the foundations is impressive; the area encompassed by the footings can nearly fit within a high school basketball court, and each cap weighs over 2.6 million pounds. Additionally, the tower pylons, which required custom formwork and innovative cambering to counteract deflection over time, achieving vertical alignment approximately 27 years post-construction. The temporary supports for the precast U-beams involved 400,000 pounds of temporary steel towers and falsework, featuring over 5,000 linear feet of welds and 2,324 bolts, all of which were removed once cable installation was complete. Unique construction challenges included the transportation and precise placement of 130-ton precast, post-tensioned U-beams, during specific tides, by barge crane, as well as the detailed installation of basket-weave pattern cables that enhance both structure and aesthetics. This project exemplifies the integration of structural resilience, design precision, and long-term durability.

IBC 25-22: A New Iconic Bridge for Brisbane
Thomas Cooper, WSP, Melbourne, Victoria, Australia; Andrew Gallagher, WSP, Brisbane, Queensland, Australia

The Kangaroo Point Bridge is a 458-metre long, cable stayed bridge to be situated over the Brisbane River in Brisbane, Australia. It is the first of eight “green” bridges proposed by the Brisbane City Council to promote pedestrian, cycle, and e-transport across the city, connecting the built-up inner-city suburb of Kangaroo Point and the Central Business District
Crossing the Brisbane River as it winds through the central business district (CBD), the bridge will connect to two very active areas of the city, the densely residential Kangaroo Point and the centre of the CBD at the Brisbane Botanical Gardens. With a composite steel box superstructure and nearly 100-m tall steel box tower, the 183-metre asymmetric cable-stayed main span, paired with the narrow width required for a pedestrian bridge, is one of the longest of its kind internationally.
The structure’s dynamic response for wind and pedestrian (footfall) comfort criteria has been considered through wind studies, wind tunnel testing, and advanced structural analysis. This project has been delivered with a parametric digital model (300LOD), where the bridge geometry is controlled by parametric scripts.
Pedestrians are separated from cyclists and e-transport users by ample width and line marking along the bridge’s 6-meter-wide deck. The pedestrian path is shaded by a canopy supported on tapered steel posts, which cantilever at intervals from the northern edge beam. The bridge is also home to a restaurant raised above the deck near the entrance on the Botanic Garden side of the river.

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Historic

Time: 10:30 AM – 12:00 Noon

IBC 25-23: Historic Route 66 Bridgeport Bridge Rehabilitation
David Neuhauser, STV, Oklahoma City, OK; Jose Joseph, STV, Frisco, TX

The William H. Murray “Pony” Bridge, known as the Bridgeport Bridge, is a 90-year-old structure that functions as a slice of America history. Beloved by Route 66 and bridge enthusiasts alike, the iconic Bridgeport Bridge in Oklahoma boasts 38 unique 100-foot pony truss spans that attract tourists from around the world. After years of use coupled with changing traffic patterns, the aging bridge was rated structurally deficient, threatening potential closures to traffic and heavier vehicles.
The Oklahoma Department of Transportation (ODOT) selected STV to serve as lead designer for the bridge’s long-anticipated revitalization. STV also provided reconnaissance data collection, stakeholder coordination, and an Alternatives Analysis Report study during the project’s planning stage.
Tasked with preserving the bridge’s iconic features, STV’s design team developed the first highway bridge in Oklahoma to use full-depth precast concrete deck panels and Ultra-High Performance Concrete (UHPC) joints. The widened bridge can now safely carry more vehicles across the South Canadian River, while the new parking lot and viewing area at the end of the bridge make it easier for tourists to experience this Route 66 destination.

IBC 25-24: Rehabilitation of the Historic Monument Place Bridge
Matthew Bunner, HDR, Pittsburgh, PA; Anthony Ream, HDR, Pittsburgh, PA; Ahmed Mongi, HDR, Charleston, WV

The Monument Place Bridge, constructed in 1817 near Wheeling, was a part of the original National Road and is the oldest bridge in West Virginia and among the oldest bridges still in service in the country. The bridge is a unique and rare example of a three-span stone arch that features the elliptical style of arch geometry. The structure was updated in 1931 when the original barrier walls were removed and replaced with overhanging concrete sidewalks and balustraded parapets. In 1958, a concrete shotcrete was applied over the stone, giving it the appearance of a concrete arch bridge.

Over the years, the original masonry along with the updated portions of the bridge had deteriorated significantly. This project involved the investigation and evaluation of the condition of the bridge, including analysis. Various rehabilitation options were evaluated, and final design of the selected scheme was performed. The project team dealt with many complexities including lack of design information, obscured portions of the structure, coordination with FHWA and the SHPO due to the historic nature of the bridge, adjacent properties and utilities, and preserving the appearance while upgrading the bridge, which remains on a well-traveled portion of US Route 40.

Tools such as LiDAR survey, pilot contracts for removal of portions of the shotcrete, geotechnical and material testing, masonry arch analysis, and photo documentation were utilized. This presentation will present both design and construction phases of the project, which will be complete before IBC 2025.

IBC 25-25: Adaptive Reuse of the Historic Mount Carbon Bowstring Truss
Mike Urban, Gannett Fleming TranSystems, Audubon, PA; Brian Teles, Gannett Fleming TranSystems, Audubon, PA

PennDOT discovered a rare bowstring truss in Mt. Carbon, Schuylkill County, prompting a project supported by numerous stakeholders to provide new life for this unique truss. The project involved the relocation, restoration, and adaptive re-use of an 1878 NRHP eligible truss which has had four owners and three locations. The truss is part of a new trail for the Schuylkill River Greenway Association over Mill Creek in St. Clair, PA.

This truss was perfect to use as a pedestrian bridge for the Adaptive Reuse program for relocating historic trusses to extend trail networks. It is on a publicly accessible trail, and is in a highly visible location near SR 61 and a shopping center. It tied into the center’s industrial theme and presented an opportunity to publicly showcase the County’s history.

Not only was restoring a bridge originally a challenge but moving it from one location with limited access and fitting it into its new location took careful planning. Construction consisted of lifting the bridge in its entirety and moving to a staging area to be disassembled. It was shipped to an Ohio blacksmith who used new hot driven rivets to restore the truss. At the new location, new abutments were constructed, and the staging area was prepared for reassembly. With an even tighter window, the contractor had to truly thread the needle to place the bridge onto the new abutments.

The project is an excellent example of preserving historical structures via adaptive re-use on multi-modal transportation infrastructure.

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Bridge Replacement

Time: 10:30 AM-12:00 Noon

IBC 25-26: Pier Replacement with Temporary Crash Wall
Gregory Stolowski, WSP, Lawrenceville, NJ; Anand Patel, WSP, Lawrenceville, NJ; Alex Beyer, WSP, Lawrenceville, NJ

The rehabilitation of the historic 3.5-mile Pulaski Skyway, connecting Jersey City to Newark, NJ, presented a unique challenge: replacing Pier 20 and its bearings on Spans 19 and 20. Limited space around the pier, including Conrail tracks and low headroom, demanded innovative solutions.
This project implemented a multi-functional crash wall system. It served as temporary support for the superstructure during Pier 20 replacement, withstanding extreme loads from both construction and potential collisions. Importantly, the design also transitioned seamlessly to become a permanent crash wall after construction, protecting the bridge from future impacts. Micropiles were used due to limited workspace and low vertical clearance. This presentation will detail the design considerations for the crash wall’s dual functionality, the construction methods addressing site constraints, and the crucial coordination with Conrail, surrounding utilities, and the New Jersey Department of Transportation (NJDOT).

IBC 25-27: Yellowstone River Bridge Replacement – Unique Solutions in a Unique Environment
Bob Sward, Structural Technologies, LLC, Fort Worth, TX; Sean McAuley, JACOBS, Denver, CO

The Yellowstone River Bridge Replacement project utilized a number of unique details, construction methods and technologies to build a long span, high level crossing over the Yellowstone River in Yellowstone National Park. The new bridge stands 175’ above the river and spans geothermal and hydrothermal hazards in a remote area of the country with limited construction access and seasons. The bridge features segmentally constructed precast columns to maximize the summer construction season along with lead-rubber bearings for improved seismic performance. The lead-rubber isolation bearings allowed the team to balance the stiffness of the structure and provide a primary response to seismic demands which should limit total damage to the structure in earthquakes. The columns also featured detailing for improved seismic ductility, featuring grouted energy dissipating reinforcement within the bottom column segments and microcrystalline-wax filler in the PT tendons to allow distribution of strains and prevent tendon rupture at joint openings. The steel girder structure was designed and constructed to lay lightly on the land and minimize both visual and physical impacts to the surrounding landscape.

IBC 25-28: CTA Harlem Transit Station Bus Bridge Replacement – Multi Discipline, Design, Construction & Innovation
Irsilia Colletti, P.E., S.E., HNTB, Chicago, IL; Tony Shkurti, Ph.D., P.E., S.E., HNTB, Chicago, IL; David Budzik, HNTB, Chicago, IL

The CTA Blue Line Harlem Station Bus Bridge Rehabilitation replaces the existing three-span steel superstructure with an improved two-span continuous steel girder design which will reduce the number of expansion joints on the bridge from three to zero, maintain the limited existing clearances to the interstate highway below, and utilize the existing substructure units and foundations. The length of one span was increased by 150% to replace two spans on the existing bridge while maintaining the same structural depth due to clearance and vertical profile restrictions. The innovations that facilitated the design include conversion of the existing stem wall abutments to semi-integral, an integral steel pier cap fabricated as one transportable unit that are supported by three steel W columns with a portion of the girders up to splices on either side of the cap and geophysical testing which justified an increase of the capacity of the pier foundation. The integral pier cap also features a large web opening beyond the scope of AISC design guidance, which led to the design of an innovative web opening reinforcement detail using nonlinear FEA buckling analyses.

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Cable Stay Bridges

Time: 10:30 AM – 12:00 Noon
Room: Salon I

IBC 25-29: Reprofiling of An Existing Cable Stayed Bridge – US 17/SR 404 SPUR BRIDGE
Meng Sun, Parsons Transportation Group, Denver, CO; Robert Orsa, Parsons Transportation Group, Denver, CO; Greg Shafer, Parsons Transportation Group, Baltimore, MD; Kira Hamilton, Parsons Transportation Group, Denver, CO; Gernot Komar, Denver, CO

The US 17/SR 404 Spur Bridge (Talmadge Memorial Bridge), a pivotal cable-stayed structure connecting Savannah and Hutchinson Island, is undergoing a significant $189-million maintenance and upgrade project. Originally completed in 1991, the bridge currently features a 1,100-ft main span carrying State Route 404 and US 17, with a 185-ft clearance over the Savannah River, which restricts the Port of Savannah’s ability to accommodate the largest modern container ships. The proposed solution is to raise the bridge profile by shortening the stay cable so that the bridge air draft reaches 206 ft.

Cable geometry is one of the critical design items for the bridge reprofiling. The cable length, cable angle, permanent angle deviation, cable shortening, and cable stressing length have been evaluated from the surveyed bridge profile to the final raised profile. Construction staging models have been developed to analyze the detailed cable stressing and bearing jacking sequence and steps with consideration of temporary loading on the bridge. Fifteen main cycles with over 500 steps were evaluated to account for local and global effects in the overall structure. The bridge capacity has been evaluated for service and strength limit state during the profile raise. The final bridge geometry has been cambered to compensate the long-term time dependent effect of aged concrete under the new loading.

IBC 25-30: The Mast: Designing a Signature Cable Stayed Pedestrian Bridge
Hunter Ruthrauff, TYLin, San Diego, CA; Bobby Sokolowski, TYLin, San Diego, CA

Inspired by the naval history of Erie, PA, the Holland Avenue Pedestrian Bridge is a cable stayed structure that crosses over the Bayfront Parkway connecting the core of downtown to the waterfront. The structure features a “mast-like” steel pylon and an asymmetric stay arrangement that is reminiscent of sails commonly seen in ships of Erie’s past. The project is also highly focused on landscape integration as seen in its northern approach where the pathway snakes up to the bridge elevation with planters and trees interspersed throughout. The project also focuses on social space activation around key structures such as a halo bench around the base of the pylon and an overlook region at the apex of the northern approach.
This presentation will walk viewers through the origins of concept development including the type selection process that studied a variety of alternatives that ultimately led to the emergence of the alternative that is currently in construction. The presentation will also focus on the parametric design workflows from an architectural sense along with the interoperable programs used for structural analysis and the rebar model that was critical in identifying conflicts during construction documentation. The presentation will cap off with a review of the current state of construction and the challenges and solutions that have arisen during that process.

IBC 25-31: Inspection of Modern Stay Cable Systems
Mark Saliba, P.E., Freysinet Inc., Sterling, VA

Modern Stay Cable Systems, used almost exclusively in the US over the last 25 years, and for longer periods in regions outside the US. Modern Stay Cable Systems consist of parallel 7-wire strands, individually protected against corrosion, installed inside pipes; without filling the void space with the pipe. Systems installed for the prior 25 years generally consist of parallel wires or 7-wire strands installed inside pipes, and once tensioned to final loads the pipes were injected with cementitious grout for corrosion protection.
Advantages provided with Modern Stay Cable Systems include the ability to perform complete and thorough inspections from end to end. Modern Stay Systems also offer the ability repair, remove and/or replace individual stands, various system components and if needed, complete detensioning, removal and replacement of an entire stay cable. A most attractive feature is all these activities can be performed with the bridge in-service, and many performed with minimal impact on traffic.
Case studies of inspection programs will present the scope of recommended inspection tasks, including frequencies, corrective actions, means and methods and explain routine and special inspections. Typical findings will be presented as will the value of well documented asset inspection data to understand the findings year-over-year, allow for re-allocation of inspection efforts, frequencies, etc.
Implementation of a comprehensive inspection and maintenance program removes the risk of a relatively minor issues (caused during construction or early in-service) being undetected and left unattended, developing into very significant issues requiring expensive repairs/replacements and severe traffic impacts in the future.

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Analysis/Research/Design I

Time: 10:30 AM – 12:00 Noon

 IBC 25-32: A Bridge Widening at an MSE Retaining Wall Conflict
Cory Shipman, HDR, Dallas, TX; Jeffrey Svatora, HDR, St. Louis Park, MN; Stanley Oghumu, HDR, Dallas, TX

Mechanically Stabilized Earth Retaining Walls (MSE) are commonly used to wrap around a bridge abutment. However, this can present challenges to future designers when widening the bridge. The existing MSE straps conflict with proposed deep foundations and construction operations can cause distress in existing wall panels. HDR encountered this design scenario when widening twin bridges on the Sam Rayburn Tollway over Hebron Parkway in Carrollton, Texas. HDR met with the North Texas Tollway Authority to discuss potential solutions and, after considering several solutions, decided to support the proposed widening in front of the existing MSE Retaining Wall. To support the interior widening of the bridge, a new support bent was designed and constructed immediately in front of the MSE wall. This resulted in new girders cantilevering approximately 5 feet over the support bent and MSE wall embankment. The existing beams remained simply supported at the existing abutment behind the MSE wall. This difference in geometry caused a differential deflection issue between the cantilever ends of the proposed beams and the existing beam ends supported on bearings. With the application of loads at midspan, the ends of the proposed girders tend to deflect upwards, relative to the existing simply supported beams. As a result, high stresses in the deck are generated. These stresses are further amplified due to the relatively narrow beam spacing of 5.5 feet. A refined analysis was performed for this problem utilizing a 3D plate and eccentric beam model in LARSA with a 2D influence surface.

IBC 25-33: Fatigue Assessment of Long Span Bridges
Neerajkumar Desai, Associated Engineering Consultants, Mumbai, Maharashtra India; Jayashree Desai, Associated Engineering Consultants, Andheri West, Maharashtra India

The process of progressive localized permanent structural change occurring in a material subjected to conditions which produce fluctuating stresses and strain at some point or points and which may culminate in cracks or complete fracture after a sufficient number of fluctuations is known as Fatigue phenomena.
This paper describes the considerations involved in the design and fatigue assessment of various types of steel bridges for different types of loading i.e highway, metro rail and broad gauge railway through case studies of projects executed recently. The primary focus is in the domain of Railway bridges wherein a large volume of traffic and high cyclical loadings are experienced over the service life. The paper draws upon experience gained in design of long span trusses ranging from 47.0m to 103 m covering different types of connections and classification of welds as per EURO and IRS/BIS norms.
It is observed that several attachments such as batten plates, diaphragm plates in tension chords and lacings in tension diagonals and several other such secondary attachments to primary load carrying members have the effect of reducing the fatigue category.
The robustness and economy of the design depends not only upon selection of optimal section sizes but also the type of weld detail class and welding methodology adopted so also the ease with which the fabrication can be done. The practical difficulties associated with the fabrication of long span trusses with welded/bolted connections needs extensive planning in design office to give an economical and robust design.

IBC 25-34: Refined Load Rating of a Bridge with Unique Reinforced Concrete Arch and Stringer-Floorbeam Spans
Lung-Yang Lai, Ph.D., P.E., S.E., Specialty Engineering, Inc., Bristol, PA; Garry Calotta, P.E., Pennsylvania DOT, Allentown, PA; Andrzej Trela, P.E., Pennsylvania DOT, Allentown, PA; Brian LoCicero, P.E., Specialty Engineering, Inc., Bristol, PA

The American Parkway Bridge in Allentown, Pennsylvania was originally constructed in 1956。 The bridge consists of cast-in-place reinforced concrete and steel approach spans, and the main span is a reinforced concrete open-spandrel arch structure。 The bridge was widened in 1987。 The widened portions of the superstructures in the concrete approach spans and arch span were constructed with pre-cast concrete members。 In 2015, some members in the concrete approach spans and the arch span were strengthened with CFRP due to cracking and spalling on many stringers and cross beams。
A load rating was conducted using the Load Factor Design (LFD) methods along with an in-depth inspection。 Load rating of the cast-in-place concrete structure required combining three-staged analyses considering staged-construction。 Three-dimensional analyses were used to compute axial forces and moments in the arch ribs and columns。 Axial force and Moment (P-M) capacity curves based on strain compatibility were developed for the load ratings of arch ribs and columns。 The concrete stringers and floorbeams in the concrete spans support two-way slabs, in contrast to one-way slabs in typical bridge structures。 Two-dimensional analyses showed that live load distributions are different from the AASHTO live load distribution factors。 From the 3-Dimensional analyses, torsional forces were observed in some concrete stringers and floorbeams。 The torsional effects were not observed with typical line girder analyses and could be the reason for the observed cracking。 The effects of CFRP strengthening were also studied。 It was determined that some strengthening may not be as effective as expected。

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