Engineers' Society of Western Pennsylvania


337 Fourth Avenue
Pittsburgh, PA 15222

Phone: (412) 261-0710 Email: Get Directions

Tuesday, June 4, 2024

Technical Sessions

Rehabilitation Design 1

Time: 1:30-3:00 PM

IBC 24-35: Suspended Truss Span Rehabilitation of Wind Shear Devices
Greg Roby, P.E., Stantec, Baltimore, MD; Ruel Sabellano, Maryland Transportation Authority, Baltimore, MD

The Millard E. Tydings Bridge (I-95 over Susquehanna River in Maryland) was built in 1962. It’s an
87-foot wide by 5,061-foot-long steel deck truss consisting of anchor spans and suspended spans. The suspended spans are 245 feet long and are hung by vertical members from the cantilevered anchored spans. Wind shear devices keep the suspended spans aligned. This project involved an innovative way to rehabilitate and restore these devices with minimal impact to traffic. The original 1962 wind shear device consisted of steel-on-steel wear plates carrying the vertical weight of the devices and longitudinal wear plates to keep the spans aligned. After 20 years of wear and deterioration, in 1984 the original devices were retrofitted with new devices atop of the original devices. This allowed the original devices to perform while the retrofits were installed. The 1984 retrofits utilized elastomeric pads on the vertical and horizontal wearing surfaces. The elastomeric pads eventually fell out, transferring the extra dead weight to the original device, along with the original device now performing the full function of a wind shear device. This accelerated deterioration of the original devices which resulted in the need to completely rehabilitate all the bridge’s wind shear devices. Stantec developed an innovative approach to rehabilitate both the original and 1984 retrofit wind shear devices with minimal impacts to traffic. Now the Tydings Bridge has an original and backup wind shear device at each of these critical locations. Various other truss and substructure repairs were completed at the same time.

IBC 24-36: Rehabilitation of the Historic Union Bridge over the Ottawa River
Amer Hammoud, M.A.Sc., P.Eng., Patrick Mergel, and Peter Harvey, Parsons, Ottawa, ON, Canada; Thierry Tremblay Prebinski, and Paul Lebrun, Public Services and Procurement Canada, Gatineau, QC, Canada

The Union Bridge, built in 1919 and owned by Public Services and Procurement Canada, is a 71.5 m long single-span riveted steel through truss bridge spanning the main channel of the Ottawa River downstream of the Chaudière Falls. The Union Bridge serves as a vital transportation link along the Chaudière Crossing, the oldest crossing over the Ottawa River in Canada’s National Capital Region, linking the City of Ottawa in the Province of Ontario with the City of Gatineau in the Province of Quebec. The inspection and evaluation of the 100-year-old structure identified multiple components that are in critical need for repair or replacement. Active transportation improvements including construction of new raised concrete cycle tracks were also required. Rehabilitation work included concrete deck replacement, stringer replacement, floor beam strengthening, truss members strengthening, structure jacking, bearing replacement, structural steel recoating, approach slabs replacement, new waterproofing and asphalt wearing surface, new fibre-reinforced polymer sidewalk, new parapet wall and railing, and substructure rehabilitation. Since the bridge serves as an important route for vehicles and transit between the two cities, a minimum of one open traffic lane was required to be maintained throughout construction. Restrictions and considerations due to the staged construction, limited access and the extensive rehabilitation of the structure’s main components presented numerous challenges that required detailed analysis, planning and sequencing of work.

IBC 24-37: Bringing New Life to an Old Bridge through Effective Teamwork
Andrew Goodrich, P.E., Burgess & Niple, Parkersburg, WV; Dan McCaffrey, Modjeski and Masters, Mechanicsburg, PA; Andrew Adams, Modjeski and Masters, Mechanicsburg, PA

Previously owned by the City of Parkersburg, WV, a toll bridge locally known as “Parkersburg Memorial Bridge” serves as a key link between Parkersburg and the City of Belpre, OH. The 70-year-old steel structure was in serious need of rehabilitation to remain in service; however, the funds needed for such a project were above the means of the city.

In early 2021, after a Request for Proposal process, the City of Parkersburg entered a Public-Private Partnership with United Bridge Partners (UBP), a company whose mission is to offer solutions to state and local governments to replace or repair bridges in need. Under this partnership, UBP would acquire the bridge and provide 100% of the funding to rehabilitate the bridge. UBP formed a local subsidiary, Parkersburg Bridge Partners, which will provide long-term operation and maintenance.

Using the Construction Manager/General Contractor (CM/GC) Method for this project, UBP teamed with Modjeski and Masters as the design engineer, Kokosing Construction Company as the General Contractor, and Burgess & Niple as the Owner’s Engineer/Field Representative during construction. This $50+ million project included extensive repairs and replacements of steel components including pin & hanger-to-splice retrofits in the multi-girder approach spans, strengthening of steel truss members, deck replacement using fiber-reinforced concrete and galvanized rebar, patching and coating of all concrete substructures, complete blast & painting, installation of an upgraded roadway & decorative lighting system, and implementation of an all-electronic tolling system.

The presentation will focus on the rehabilitation scope and the effective partnering among the entire team.

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Construction Engineering 2

Time: 1:30-3:00 PM

IBC 24-38: Falls Creek Bridge: Design For a Mountainous Site Washed Out by Atmospheric River
Borja Alverez, P.Eng., Stantec, Victoria, BC Canada; John Philip, P.Eng, MICE, C.Eng., Stantec

This case study describes the challenges and structural solutions analyzed and adopted for the permanent reinstatement of a bridge crossing on the Trans-Canada Highway 1 at Falls Creek in British Columbia, Canada, where an existing embankment and culvert was washed out by the atmospheric river event of November 2021. Initially the highway was reopened with a temporary 80 m single-span Acrow bridge carrying a single lane of traffic operating under an extended length of SLAT (Single Lane Alternating Traffic) to maintain traffic flow over the wide steep gulley that resulted after the washout. The main objective was the rapid restoration of two-way traffic allowing removal of the costly SLAT and ultimate completion of a three lane structure. The presentation will describe how the design of the permanent works was influenced by the site constraints, schedule requirements and location as well as the effect such constraints had on choosing the erection method. The construction of the bridge, a 79 m curved steel plate girder span involving precast components, girder launching, and lateral sliding is described in a second paper and presentation at the conference. The project is being delivered under an Alliance Contracting model, which involves an integrated team of Owner, Contractor, and Designer.

IBC 24-39: Falls Creek Bridge: Accelerated Bridge Construction With Precast, Launching and Lateral Sliding
Murray Johnson, P.Eng., Stantec, Vikram Verma, P.Eng., BC Ministry of Transportation and Infrastructure

The Trans-Canada Highway at the Falls Creek site had been operating under single-lane alternating traffic ever since an atmospheric river event washed it out in November 2021, with an urgent need to reopen it to three-lane traffic. Working under the Alliance Contracting model, the project team employed a variety of accelerated bridge construction methods to construct the 79 m curved steel plate girder span while maintaining traffic on the single-lane emergency bridge that occupied part of the permanent bridge alignment. Construction techniques included innovative partial-shell precast abutment elements, launching of curved steel girders in pairs, offline opening of the permanent bridge to traffic while the temporary bridge was removed, and lateral sliding of the completed bridge into the permanent alignment during a short traffic closure. The steep mountainous terrain in a semi-remote area provided a highly constrained construction site with multiple challenges overcome by the integrated Alliance team who worked together on all elements of design and construction. The design of the permanent structure including the impacts on design resulting from the intended construction techniques is described in a second paper and presentation at the conference.

IBC 24-40: Walk Bridge Project: The design journey of replacing a historic movable rail bridge in a busy Northeast Corridor, from bridge type selections to creating an aesthetic structure reflecting the community of Norwalk, Connecticut
Jesse Miguel, AIA, NCARB, ENV SP, HNTB, Kan, MO; Christian Brown, HNTB, Kans, MO; Jeffrey Portal, Connecticut DOT, Newington, CT

The Walk Bridge, is a 127-year old swing span railroad bridge over the Norwalk River, listed on the National Register of History Places, and part of Metro-North Railroad’s New Haven Line and serving as the link to the nation’s busiest rail corridor, the Northeast Corridor. Listed on the National Register of Historic Places, the Walk Bridge has reached the end of its useful life, failing to operate properly disrupting rail service, and requiring several emergency repairs. In 2011 the constant pattern of failures became apparent, and after failing twice within a 2-week week in 2014, the ConnDOT Commissioner signed an Emergency Declaration, resulting the need to replace the bridge. The final design chosen is a vertical lift bridge, selected for allowing the least disruption to rail service while under construction.

The design process consisted of studying various bridge type options, primarily movable bridges but also some fixed high bridges, required to maintain the navigational channel as required by the US Coast Guard. These options were reviewed and evaluated and initially a twin bascule option was selected. But that required having to construct a temporary run around bridge carry two tracks to allow construction, which led to the final selection of the vertical lift span bridge, construction started in Spring 2023.

The new Walk Bridge will be aesthetically designed per the City of Norwalk with review by their Design Advisory Committee, due to its location in a historic South of Norwalk district and becoming the symbol of the area.

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Design & Analysis-Urban Interaction

Time: 1:30-3:00 PM

IBC 24-41: Jane Byrne Interchange: Complex Interchange in Historic Urban Environment
Matthew Santeford, P.E., S.E., TranSystems, Schaumburg, IL

The Jane Byrne Interchange (Circle Interchange) is the hub of the Chicago Expressway System: the convergence of the Kennedy, Dan Ryan, and Eisenhower Expressways (I-90/94 and I-290) in downtown Chicago, accommodating 400,000 vehicles per day (25% trucks). In 2012, the interchange was rated by the American Transportation Research Institute and the FHWA as the #1 freight bottleneck in the country, a distinction the Illinois Department of Transportation was motivated to address.

This $640M reconstruction project was a massive undertaking. It was a complex, challenging exercise to essentially rebuild the interchange within, and on top of, the existing interchange. The project involved the reconstruction of 19 bridges (including 7 curved steel girder ramp bridges, two of which were tri-level flyovers), nearly 50 retaining walls, and over 32 miles of expressway lanes.

Adding to the complexity were ten service interchanges within the project area. Two of these service interchanges, at Adams Street and Jackson Boulevard, required complex steel framing to accommodate the entrance ramps that “T” into the side of the crossroad bridges. Each of these structures are also adjacent to sensitive, historic structures, making construction vibration a serious concern.

This presentation will provide an overview of the Jane Byrne Interchange project, as well as focus in on the details of the complexity of the Adams Street and Jackson Boulevard service interchanges. The bridge design as well as the design of 20’ tall retaining walls founded in soft clay material will also be discussed.

IBC 24-42: Bridge Rehabilitation in the Heart of Our Nation’s Capital
Ahmad Faqiri, HDR, Vienna, VA; Jeffrey Hollands, P.E., HDR, Washington, DC

Over half a mile of an elevated portion of the I-695 Freeway in Washington, DC is comprised of three main bridges and 10 ramp bridges. Bridge 1103 and its ramps, approximately 800 feet long, are a series of simple prestressed bulb-tee spans ranging from 50 to 150 feet long supported on reinforced concrete pier bents. Bridges 1104 and 1109, approximately 550 feet and 1500 feet long respectively, are primarily a series of simple steel plate girder spans ranging from 50 feet to 260 feet long supported on steel cross-girders and reinforced concrete columns. Several of the steel plate girder spans include pin and hanger connections. Theses bridges span over parking lots, local roads, and CSX facilities, resulting in complex bridge shapes. Built in the 1960s and rehabilitated in 1990s, these bridges are in poor condition, needing deck repair, joint replacement, beam repair, pin and hanger retrofit, bearing repair, pier/cross girder repair, and column/abutment repair. Due to the highly urbanized location of this project and the importance of the freeway to the transportation network of the US capital city, MOT is a major component of the project. To mitigate the risk and reduce the construction duration, the design team has proposed accelerated bridge construction methods such as use of ultra-high-performance concrete for the bridge deck overlay and some of the other repairs such as link slabs and joint replacements. Additional innovative rehabilitation techniques, to enhance bridge preservation, include metalizing of concrete and catcher beams at pin-and-hanger locations.

IBC 24-43: Pittsburgh International Airport Terminal Modernization – Construction overview and opening preview
Kevin O’Connor, HDR, Pittsburgh, PA

The Pittsburgh International Airport Terminal Modernization Program (PIT-TMP) will be approximately 90% complete at the time of the IBC in 2024. When the 2025 IBC comes back to Pittsburgh the Airport will be completed and open, and many of the conference attendees will pass through the new facility. The PIT-TMP is a terminal and roadway project that includes architectural and art elements as part of the Terminal Front Bridge and retaining walls. This presentation will show construction photos of the nearly complete facility and compare to renderings and mockups that were produced in design to illustrate the successful execution of the project vision. The PIT-TMP was designed using an overarching concept of Nature, Technology, and Community (NaTeCo). This concept is evident in the design of the Terminal, the bridge and retaining walls, and the terminal curbs on the bridge. The bridge design team also paid special attention to the user experience at the terminal curbs on the bridge, which is an area that is often neglected in airport design.

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Foundation Design & Analysis

Session Chair: Nicholas Burdette, P.E., HDR, Pittsburgh, PA
Time: 1:30-3:00 PM

This session highlights the challenges overcome by bridge foundation designers including extreme scour, load testing requirements, vibration limits, and railroad deflection criteria. These case studies show that though they are hidden below ground in the final structure, design of efficient bridge foundations requires all the art and ingenuity of the highly visible superstructure.  These examples of challenging bridge sites will help session participants learn design approaches for efficient deep foundations, which require a close partnership of structural and geotechnical engineering.

IBC 24-44: Widening an Interprovincial Bridge over the Ottawa River
Ryan O’Connell, P.Eng., Parsons, Ottawa, ON Canada; Jack Ajrab, P.ENG., Parsons, Ottawa, ON Canada; Paul Lebrun, P.Eng., Public Services and Procurement Canada, Gatineau, QC, Canada; Thierry Tremblay, P.Eng,, Public Services and Procurement Canada, Gatineau, QC, Canada

The Hull Causeway is an existing three-span, two-lane steel girder bridge, part of the Chaudière Crossing, connecting Ottawa, Ontario to Gatineau, Quebec over the Ottawa River. This paper will focus on widening the structure and the design challenges associated with it. Widening the structure required the addition of a new plate girder, widening of the abutments and introduction of an approach span and associated substructure and foundation. The north end of the structure spans across the Devil’s Hole, a karst feature which has existed for a period of time dating back to the 1800’s. The presence of hole presented challenges for widening as the new steel girder required widening of the abutments. At the south end of the structure, mircopiles were capable of supporting the structure. Supporting the north end of the structure, which is located directly next to the Devil’s Hole, with new caissons, would require a design based on a total length of approximately 50m and unsupported length of almost 45m. As a result of the caisson required, and its associated cost and potential construction impact on the existing structure, an alternative design was completed. The existing abutment would be widened and supported by a series of rock anchors tied in to the solid bedrock under the existing abutment. The new north approach span abutment was required to be in an area whose stability is controlled by a crown pillar along with sliding of a fault feature. To stabilize the foundation, a series of rock anchors were installed.

IBC 24-45: New River Draw Bridge Design and Analysis for Cooper E80 Locomotive Loads
Aravinda Ramakrishna, P.E., Hardesty & Hanover, Hamilton Township, NJ; Brian Mileo, P.E., Hardesty & Hanover, Hoboken, NJ; Kevin Gurski, P.E., Hardesty & Hanover, Hamilton Township, NJ

This paper presents the foundation design aspects for the new River Draw Bridge project in New Jersey. The new bridge piers are founded on clusters of 8.0 ft diameter drilled shafts with shaft tip elevations varying from 180 ft to 230 ft below water line to satisfy the American Railway Engineering and Maintenance-of-Way (AREMA) Manual requirements, which requires bridge foundations to safely withstand Cooper E80 locomotive live loads. This paper also discusses the results of the static load test program implemented to verify the as-built drilled shafts achieved the assumptions made during the design phase. The objective of this paper is to present the different aspects of the bridge foundation design to safety withstand Cooper E80 locomotive live loads.

IBC 24-46: The Value of Value Engineering
Austin Spencer, P.E., Pennoni, Newark, DE; Michael Alestra, P.E., Newark, DE

Pennoni was retained by the contractor, RE Pierson Construction Company to redesign the foundation for a proposed moveable bridge replacement to accelerate the project schedule as a value engineering alternative. The proposed bridge replaces an existing 10 span twin leaf bascule bridge and consists of 67.5 feet wide, 664 feet long, six span bridge with a 105-feet long bascule center span crossing the Shrewsbury River from Rumson to Sea Bright, New Jersey. The original replacement design proposed founding the abutments and piers on five-foot diameter drilled shafts ranging in length from approximately 90 to 126 feet. As part of this alternate foundation design, the contractor sought to replace the drilled shaft piles with 42-inch concrete filled steel pipe piles, ranging in length from approximately 90 to 140 feet.
The geotechnical design consisted of determining geotechnical axial and lateral capacities as well as vertical and lateral pile displacements. The structural design consisted of steel pipe pile structural capacity, and the bridge foundation reinforcement was redesigned for the revised pile layout.
Extensive coordination was required with Pierson, Monmouth County, NJDOT and the original design consultant throughout the fast-tracked design development process with project design criteria that included maintaining the pier foundations/pile caps footprint, minimizing noise and vibration during installation, as well as limiting lateral deflections to 0.5 inches longitudinal/0.25 inches transverse for bascule piers and 1 inch for the remaining piers and abutments. Additionally, scour depths of up to 33 feet needed to be considered.

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Movable Bridges

Time: 3:30-5:00 PM

IBC 24-47: High Rise Bridge Grid Deck Replacement and Structural Repairs
Deanna Nevling, HDR, Virginia Beach, VA; Brianna Binowski, HDR, Virginia Beach, VA; Christopher Dean, HDR, Virginia Beach, VA

High Rise Bridge (HRB) is a double leaf trunnion bascule bridge located in Chesapeake, Virginia on Interstate I-64 with over 80,000 vehicles a day crossing the bridge. The existing open and concrete filled grid deck had reached the end of its service life and needed to be replaced. Several stringers and floorbeams exhibited deterioration requiring repairs to extend the service life of the structure. An expedited design, fabrication, and construction schedule was necessary to complete the repairs in sequence with the adjacent new High Rise Bridge opening to ensure hot lanes and tolling revenue could be generated through the corridor. VDOT accelerated the design schedule and procured the new grid deck directly from the fabricator concurrently with the selection of a contractor for the project. Stringer and floorbeam repairs included replacing all continuity plates, replacing severely deteriorated stringers, repairing locations of floorbeams and stringers that could only be accessed with the grid deck removed. Numerous challenges were overcome during construction due to undocumented as-built changes and fabrication tolerances. For example, grid deck channel support holes did not align with the existing holes in the stringers and bascule girders, existing railing attachments were misaligned with the new grid deck panels, and new grid deck panels did not fit longitudinally or transversely. VDOT, the fabricator, contractor, and the designer all collaborated as a team to overcome numerous obstacles to ensure the gird deck replacement and repairs were completed on time.

IBC 24-48: Vehicle Collision Repairs to an Overhead Counterweight Rolling Lift Bridge
Jonathan Eberle, AECOM, Mechanicsburg, PA; Jason Hastings, Delaware Department of Transportation, Dover, DE; Neil Shemo, AECOM, Mechanicsburg, PA

On December 28, 2021 DelDOT’s bridge 2-021A was impacted by an over height vehicle travelling on the structure. The structure, originally constructed in 1929, consists of steel girder approach spans on either side of the 55’ – 10 ½” overhead counterweight rolling lift main span and carries Rehoboth Blvd over the Mispillion River in Milford, DE. This waterway provides access for boats upstream to the Delaware Bay and the movable span operates a few dozen times a year for pleasure watercraft.
The impact sustained to the bridge occurred when the arm of an excavator being trailered north on the roadway directly impacted the portal frame above the roadway leading to significant damage to the machinery platform. AECOM was tasked with the inspection and repair design for the damage sustained. Repair drawings were prepared and the construction was awarded under an on-call contract. As construction was about to begin, the bridge was impacted a second time in a similar fashion which caused additional damage to the structure. Inspection was performed and the scope of work was modified to include additional repairs. Construction was completed under a full vehicular detour of the roadway and the bridge was reopened to navigation and vehicular traffic on August 11, 2023. This paper will discuss the findings of the inspection, the repair design and issues encountered during construction including the second impact. It will also discuss unique methods used for construction, lessons learned from the project and DelDOT’s plans to prevent future impacts to the bridge.

IBC 24-49: Collaboration to address Construction Challenges – The Loxahatchee River Bridge Rehabilitation
Steven Shaup, P.E., TranSystems, Fort Lauderdale, FL; John Williams, Wiss, Janney, Elstner Associates, Inc., Doylestown, PA

The Loxahatchee River Bridge, a simple trunnion bascule bridge in Jupiter, FL, required rehabilitation to restore it to double track service after decades of single track use. The project was initially let using design-bid-build procurement to perform superstructure replacement of the bascule and approach spans with a single extended duration rail outage. The Contractor proposed an alternate plan to reduce the rail outages to one 24-hour and one 48-hour outage. However, this required the Designer to collaborate with the Contractor and agree to alter some of the structural and mechanical details to suit the Contractor’s means and methods. During the early stages of construction, it was decided to increase the scope of the rehabilitation work to include substructure replacement for the approach spans. This work was delivered as a CMGC-type procurement working collaboratively and performing redesign on the fly, as needed.

The paper will provide background information on the design of the replacement bascule span superstructure, the alternate plan for construction proposed by the Contractor, the design collaboration process that was followed to develop the structural and mechanical design details to suit the Contractors’ plan, the process followed in the shop and in the field to install the bascule span superstructure within a short duration outage without sacrificing quality, and the design and construction process used to deliver the replacement of the approach span substructure.

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Construction Engineering 3

Time: 3:30-5:00 PM

IBC 24-50: Shop Assembly and Steel Erection on the New Nice/Middleton Bridge
Ronnie Medlock, High Steel Structures, LLC, Lancaster, PA; Tom O’Rourke, Skanska USA Civil, East Elmhurst, NY; Brian Wolfe, Maryland Transportation Authority, Nottingham, MD

The main span superstructure of this new bridge is a steel unit with field-bolted plate girders, cross-frames and lateral bracing. For successful progress of construction in the field, these shop-fabricated steel components must fit well such that erection progresses on schedule, without fit-up problems at field connections. Historically, fabricators have used shop assembly to produce and check field connections, but as fabrication has modernized, fabricators have reduced production of connections in assembly, accelerating fabrication. However, even with this reduction, some level of shop assembly is still used for checking the fit of connections. This paper describes how High Steel produced the field connections for this bridge, how much shop assembly was used to check the field connections, and, subsequently, how fit of the steel went in the field.

IBC 24-51: Complex Steel Erection Procedure for Curved Girders and Substantial Simple Spans
Sean Kennedy, EIC Group LLC, Fairfield, NJ; Michael Marks, EIC Group LLC, Fairfield, NJ

This paper details the complex and unique erection procedures for the reconstruction of four ramps, NB I-95 over the Frankford Creek, Betsy Ross Bridge to SB I-95, Betsy Ross Bridge to NB I-95, and Aramingo Avenue to SB I-95 for the revitalization of interchanges between Interstate I-95 and the Betsy Ross Bridge. This revitalization was part of Contract BR2 completed in 2023 by the prime contractor Buckley and Company and steel erector Structural Services, Inc.

IBC 24-52: Innovative Construction for a Complex Site
Kevin Heffern, P.E., S.E., Burns & McDonnell, Chesterfield, MO; Tom Ringelstetter, Kraemer North America, Plain, WI; Dennis Boll, Geotechnology, Saint Louis, MO; Joe Knapp, Genesis Structures, Kansas City, MO

The Houbolt Road Bridge was a privately funded design/build project to construct an 1880-foot major river bridge over the Des Plaines River – connecting I-80 to the nation’s largest inland port. The presence of two transcontinental BNSF tracks along the south bank required all materials for construction at the south bank to be barged across the river. Thirty-five thousand cubic yards of peat and organic muck were dredged down to a clean sand layer 20 feet below the waterline. This dredging allowed construction of an engineered-fill causeway designed to support critical crane lifts. Shallow bedrock at the north bank prevented the construction of a sheet pile dock wall that could support crane-loading the girders onto barges to ship across the river. Instead, an innovative steel loading ramp system enabled 150-foot-long trucks to be driven directly onto two barges lashed end-to-end and deliver the girders to the south bank. The multi-girder system for the 460-foot main span was assembled on a custom-designed barge system at the north riverbank and erected with strand jacks to minimize maritime disruptions. The assembly and erection were performed for the four upstream girder lines and repeated for the four downstream girder lines. Each 750-ton lift was accomplished in less than four hours.

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Design & Analysis-Ped Bridge

Time: 3:30-5:00 PM

IBC 24-53: An S-Curved Tied Arch – An Overnight Success: Design and Construction of the Northaven Trail Pedestrian Bridge
Gregor Wollmann, HNTB; Kira Larson, HNTB; Ted Zoli, HNTB; Nathan Petter, Texas DOT

The Northaven Trail Pedestrian Bridge will carry bicycle and pedestrian traffic across US 75, Central Expressway, in north Dallas, connecting three highly-used trails in the region for the first time. Its signature element is a 201-ft span network tied arch across the freeway. The arch sits on skewed piers, has a basket handle arrangement, and features an S-curved deck. These features created unique challenges that had to be addressed during the design and construction of the structure.

Central Expressway carries 250,000 vehicles a day. Full closures of the 8-lane highway and frontage roads were not an option and it was imperative to minimize impacts to traffic during construction. This challenge was solved by fabricating the steel arch in its entirety, including the concrete deck, in a parking lot located about 1,000 feet from the bridge site. The completed 800,000 lb arch was then moved into its final position using self-propelled modular transporters (SPMTs) and a lateral launching system during a single overnight traffic closure.

The presentation will present both design and accelerated bridge construction (ABC) considerations for the Northaven Trail arch span.

IBC 24-54: The Nancy Pauw timber shallow-arch footbridge
Leon Treder, P.E., StructureCraft, Abbotsford, BC, Canada; Gerald Epp, StructureCraft, Abbotsford, BC, Canada

The Nancy Pauw timber shallow-arch footbridge was completed September 2022 in the town of Banff, Alberta, one of the most picturesque locations of Canada’s first national park. StructureCraft responded to the challenging brief with a low profile clear span solution using natural materials, and creating minimal environmental impact.

The bridge spans 80m across the Bow River, and with an approximate rise-to-span ratio of 1:20, the structure invites all the challenges of a shallow arch structure. These include nonlinear behavior, potential for snap-through buckling, significant abutment thrusts, susceptibility to unsymmetrical loading, and vulnerability to vibration.

StructureCraft as design-builder was responsible for the concept, design, fabrication, and erection of the superstructure, as well as turnkey delivery of the entire bridge project. Vibration and soil-structure interaction analysis were critical to success.

The curved glulam girders with a special layup were fabricated in long sections and assembled on-site. The erection procedure involved two mobile cranes simultaneously lowering the halves of the bridge assembly into place, with only millimeters of tolerance to activate the arch thrust.

Once the final midspan elevation was confirmed by real-time survey, the crew fastened the final fixed connections. After the installation of the deck, dynamic testing took place, and the necessity of a planned custom-made tuned mass damper was confirmed to mitigate accelerations.

The unique challenges of a timber shallow-arch bridge demanded holistic engineering and erection design and greatly benefited from the design-build model to achieve a beautiful, natural solution, while ensuring both constructability and economy.

IBC 24-55: Curved, Variable Depth, Propped Cantilever, Post-Tensioned Bridge
Dean Van Landuyt, P.E., AEC, A TYLin Company, Austin, TX; Nick Koontz, P.E., AEC, A TYLin Company, Dallas, TX; Logan Golla, AEC, A TYLin Company, Austin, TX

The Cypress Grove pedestrian bridge crosses Waller Creek at the edge of the new $66M Waterloo Greenway park project in downtown Austin, Texas. The available profile was extremely limited due to the high floodwater elevation and restricted ADA path. Structural difficulties were compounded by a 68’ path radius, 87’ span, and prohibition against columns in the creek. Engineers were also challenged with creating an attractive structure in this 1.5-mile long creek-side path coursing thru the heart of the new entertainment and convention center district.

The result is a curved, torsionally-stiff, variable depth, post-tensioned concrete bridge that arcs nearly a quarter-circle without support. The propped cantilever requires a full-moment connection between the span and drilled shaft foundation on the western bank. The foundation consists of three 36” diameter compression shafts near the bank and three 24” diameter tension shafts 7’ behind. The lightly loaded east end is supported on two neoprene bearing pads located on a small, simple abutment ensconced in a wrap-around mechanically stabilized rock abutment. The span depth varies from 6’ to 2’ and is post-tensioned with five 19-strand 0.6” diameter tendons.

Foundation construction commenced in July 2023. Span casting is scheduled for late October 2023.

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Asset Management

Session Chair: Nicholas Burdette, P.E., HDR, Pittsburgh, PA
Time: 3:30-5:00 PM

Many have called this the age of information, and our ability to collect and synthesize data is unprecedented.  Bridge owners are finding new ways to use this information to improve management of their assets, as they make informed decisions on the operation, maintenance, preservation, replacement, and improvement of bridges.  This session highlights several asset management case studies of moving from information to a plan of action.  Examples include both challenging individual structures as well as decision making for large inventories of bridges.

IBC 24-56: City of Pittsburgh Comprehensive Bridge Asset Management Program Overview
Louis Ruzzi, P.E., CBSI, NCTI, WSP USA, Pittsburgh, PA; Eric Setzler, P.E., City of Pittsburgh Department of Mobility and Infrastructure, Pittsburgh, PA; Alexandra Beyer, WSP USA, Lawrenceville, NJ

This paper will give an overview of City of Pittsburgh Comprehensive Bridge Asset Management Program for the City of Pittsburgh’s 146 bridges. This project was advertised in response to the January 28, 2022 Fern Hollow Bridge collapse and to ensure that the City was maintaining its bridge inventory in a structurally safe and serviceable condition. The project will recommend maintenance/preservation and rehabilitation activities and time frames for each type of activity to invest the City’s resources wisely by minimizing life cycle costs. The plan will also make recommendations optimal internal staffing levels for the City’s Maintenance and Bridges/Structures staffs. This is so the City will be able to cost effectively perform maintenance and repair activities, and to develop/implement effective asset management policies and design and deliver capital improvement projects quicker.

IBC 24-57: An Investigative Study on Extensive Transverse Deck Cracking – Two Twin Bridges
George Zimmer P.E., ENV SP, WSP USA, Lawrenceville, NJ; Alexandra Beyer, P.E., WSP, Lawrenceville, NJ; Rama Krishnagiri, P.E., WSP, Lawrenceville, NJ; Jason Hastings, MCE, P.E., Delaware DOT, Dover, DE; Kevin Lindell, P.E., Delaware DOT, Dover, DE

This case study investigates two parallel multi-span skewed prestressed concrete bridges that exhibited extensive full depth transverse and acute corner deck cracking observed soon after re-decking. The rehabilitation altered the original structural configuration which utilized a suspended span with joints and expansion bearings. These joints and expansion bearings were eliminated or modified during the re-decking. The skewed spans thermal demands are bi-directional and the new configuration, which limited transverse movement resulted in cracking and damage to the bridge. Our investigation considered the most likely causes of the cracking and considered several phased rehabilitation options to preserve the expected service life of the structures. An extensive literature review, overview of the analytical studies performed and an in-depth discussion on the many contributing factors which led to the deck cracking will be presented. Deck concrete mix, additives, pour sequence, construction records, temperatures during pour, curing methods, bearing type, response to live load demand and skew effects were considered in detail and will be discussed. Elimination of the original joints, their relocation off the bridge and the link slab design utilized for the same will be presented. An independent Finite Element Analysis to verify thermal movements, their directions and magnitude was performed, and results validated by a simple approach for reasonableness. By the time of presentation, the Phase 1 rehabilitation program should be completed with Phase 2 design underway. Results of the Phase 1 rehabilitation and ongoing monthly drone inspections to verify that cracking has subsided will be shared as well.

IBC 24-58: Inspection, Evaluation, and Rehabilitation of the Taylor Bridge Gusset Plates
Kai Marder, P.Eng., TYLin, Vancouver, BC Canada; Brook Robazza, TYLin, Vancouver, BC Canada; Dusan Radojevic, TY Lin International, Vancouver, BC, Canada

The Taylor Bridge is a two-lane six-span 712 m (2336 ft) steel truss bridge that was constructed in 1960 and crosses the Peace River in northern British Columbia, Canada. During a recent inspection of the bridge, advanced corrosion was identified on numerous gusset plates along the interface with the truss bottom chords. The British Columbia Ministry of Transportation and Infrastructure contracted the Taylor Bridge Owner’s Engineer team (Hatch Ltd., Charter Project Delivery Inc., and T.Y. Lin International Canada Inc.) to conduct a targeted inspection and load evaluation of the gusset plates.

A triage method was developed to identify a subset of 23 potentially vulnerable truss nodes. Ultrasonic thickness measurements were taken on this subset of gusset plates, providing detailed information on the variation in section loss along the length of each plate. A load evaluation that accounted for the measured section loss was performed based on the AASHTO Manual for Bridge Evaluation, with a project-specific methodology being developed to consider the significant asymmetry in the measured corrosion. A 3D non-linear finite element model that explicitly included the measured section loss in the geometry was used to validate the evaluation methodology.

A strengthening system for the deficient nodes was designed that involved installation of additional doubler plates in targeted locations. A construction procedure that temporarily relied on drift pins in place of existing rivets and bolts permitted the works to be conducted with the bridge open to traffic, with no need for temporary bracing or bypass of the affected gusset plate.

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W05: Structural Design with UHPC using AASHTO LRFD Guide Specification
David Garber, Ph.D., P.E., FHWA, Baltimore, MD; Rafic Helou, FHWA, McLean, VA

Time: 1:30 – 6:00 PM

Ultra-high performance concrete (UHPC) offers enhanced mechanical and durability properties that make it an ideal material for use in the construction, repair, and preservation of highway bridges. Research related to UHPC has been ongoing for the past few decades. Early widespread adoption of UHPC was for connections between prefabricated bridge elements, and the next phase of adoption focused on preservation and repair activities. Looking forward, the use of UHPC for primary structural members has emerged as a compelling application, as it will allow for reduced dead loads, decreased girder depths, increased span lengths, elimination of intermediate piers, and extended service life, among other possible benefits. The release of the AASHTO LRFD Guide Specification for Structural Design with Ultra-High Performance Concrete is expected to allow designers to begin engaging UHPC. The objective of this workshop is to provide background, context, and foundational knowledge to bridge owners and designers interested in using UHPC for structural applications. The workshop builds on a basic knowledge of reinforced and prestressed concrete bridge design to introduce and explain aspects of analysis and design unique for UHPC structural elements.

W06: Bridge Preservation for Existing and New Bridges
Richard Dunne, GPI, Boston, MA

Time: 1:30 – 6:00 PM

The first half objective of this Workshop will be to share with the attendees proven strategies to mitigate and reduce corrosion and other deterioration experienced by bridge decks, steel elements and concrete elements (beyond decks) on existing bridges. There will be a break. The second half objective of this workshop will be to share with the attendees design strategies being used by bridge owners to reduce corrosion potential in their new bridges and provide design details that are easy to preserve(maintain) – also known as Service Life Design.

1:30 – 2:05 Deck Preservation – Joe Stanisz, PE, Iowa DOT
2:10 – 2:45 Steel Preservation – Katy Stewart, PE, Kentucky Transportation Cabinet
2:50 – 3:25 Concrete Super & Sub Preservation – Seth Cole, PE, Texas DOT
3:30 – 4:00 Coffee Break
4:05 – 4:35 Raj Ailaney, PE, FHWA Peer Exchange Report – findings from Design Changes, Material Changes, Spec Changes section in the Report
4:40 – 5:15 Tom Murphy, PhD, PE, SE, Modjeski & Masters – FHWA Bridge Service Life Design Guide
5:20 – 5:55 Daniel Freiburger, PE, MnDOT – Bridge Service Life Design Guide (or tbd)