Engineers' Society of Western Pennsylvania

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Tuesday, July 15, 2025

Technical Sessions

Bridge Construction and Construction Engineering

Time: 1:30-5:00 PM

IBC 25-35: Contruction of the Hawk Falls Deck Arch
Josh Crain, Genesis Structures, Kansas City, MO; Jarred Musser, Pittsburgh, PA; Nick Graczyk, Pittsburgh, PA; Dave Rogowski, Kansas City, MO

This paper examines the construction challenges faced during the erection of the 480-foot Hawk Falls Deck Arch Bridge, which spans Mud Run in Penn Forest and Kidder Townships, Carbon County. As a true arch bridge, construction methods necessitated careful consideration of geometry control to ensure successful closure. The decision-making process surrounding the use of falsework towers versus tie-back systems is explored in detail, highlighting the trade-offs in terms of stability, cost, and construction efficiency.

The paper highlights the unique challenges and complexities posed by the three variable camber arches, which required careful consideration for fit-up during erection. The paper delves into the logistical considerations of employing two 1,200-ton Liebherr LR 11000 crawler cranes for setting arch segments at radii of up to 420ft. Through this case study, the paper aims to contribute to the broader discourse on arch bridge construction, providing valuable lessons for future projects facing similar challenges spanning complex terrains.

IBC 25-36: Design and Construction of an Airplane Carrying Bridge for MidAmerica Airport
Tony Shkurti, HNTB Corporation, Woodridge, IL; Allen Smith, Crawford Murphy and Tilly

MidAmerica St Louis Airport is a public use airport with a joint use agreement with Scott Air Force Base. It is because of this agreement that Boeing chose to expand their operations and build a production facility for their Unmanned Aerial Refueler (aka refueling drone). The ideal location for the production facility required a new taxiway and taxiway bridge that spanned over a small flood prone creek. The hydraulic analysis of the floodplain led us to a four span bridge with length of 419’. FAA design criteria for Taxiway Safety Area on bridges led us to a bridge width of 179’.
After a detailed bridge type study where several superstructure types were investigated, the team proposed a closely spaced prestressed concrete bridge which was determined to be cost effective a more maintenance free.
The engineers were then tasked with designing a bridge that would meet the customary structural standards of bridges, while meeting the FAA requirements for taxiways pavements. While a highway bridge must bear the weight of a semi-truck with the maximum load of 80,000 pounds, the Taxiway Lima bridge was designed to carry potential aircraft well over 580,000 pounds with an additional 30% impact factor and 25% future loading.
The paper will discuss the decision made in the type-study and the results of a design (including seismic) for a massive weight using a blend of codes.

IBC 25-37: Launched Construction of Simple-Span Structures for the Laredo-to-Nuevo Laredo Railroad Bridge over Rio Grande River
Ben Pendergrass, Genesis Structures, Kansas City, MO; Matt Struemph, OCCI Inc, Fulton, MO; Aaron Bedsworth, OCCI Inc, Fulton, MO

This paper details the construction of six plate girder spans of a railroad bridge over the Rio Grande River, connecting Laredo, Texas to Nuevo Laredo, Mexico. The spans were erected directly north of the project site on temporary falsework. One-by-one, the spans were transported onto a temporary trestle bridge positioned to the east of the final alignment using SPMTs. Each span was then transversely slid into the final alignment orientation using a hydraulic sliding system and slide beams. The spans were then sequentially launched longitudinally south along the alignment using a strand jacking system, temporary launch bents, and a roller system. Once a span was launched beyond the transverse sliding area, the following span was then transversely slid into alignment and longitudinally pinned to the previous span. The pinned spans were then progressively launched in series until reaching their final position. The pinning of the spans allowed for longitudinal launching of the simple-span structures over a total of 800-ft. Vertical jacking was then utilized to position each span onto the permanent bearings. Final placement of the spans on their bearings was successfully completed in August of 2024.

IBC 25-38: McClugage Bridge Tied Arch Span Construction and Float-In
John Boschert, Genesis Structures, Kansas City, MO; Patrick Ryan, American Bridge Company, Peoria, IL; Steve Eads, Genesis Structures, Kansas City, MO; Josh Crain, Genesis Structures, Kansas City, MO

The McClugage Bridge carries US Highway 150 over the Illinois River between Peoria and East Peoria, Illinois. The historic eastbound structure was constructed in 1939 and has reached the end of its service life. The replacement McClugage Bridge project is highlighted by a 650’ tied-arch span over the Illinois River.

The construction of the tied-arch span was planned strategically to allow for simultaneous construction activities on the arch unit and the adjacent composite steel girder units. The tied-arch span was erected adjacent to the permanent bridge on temporary falsework structures and then transported to the permanent location through a complex float-in operation on deck barges.

The layout and design of the temporary falsework structures was done to facilitate interface with the barge float-in system and included heavy pipe-pile supports, temporary telescopic arch struts and utilized historic specialty jacking falsework towers previously owned by the Contractor. The float-in operation was performed in December 2023 and successfully moved the steel arch span from the temporary erection position to the permanent position.

This paper and presentation will focus on the construction planning and engineering that were performed by the project team to construct this landmark project, including the following:
• Coordination and planning for the complex erection operations
• Design of the temporary works required to facilitate erection of the system
• Engineering for the span float-in using deck barges and specialty jacking towers

IBC 25-39: Planning and execution of bridge deck closures on the world’s longest precast segmental span
Quentin Marzari, Arup, San Francisco, CA; Jonathan Aylwin, Arup, London United Kingdom; Chris Ursery, Arup, Corpus Christi, TX; Manuel Contreras Pietri, CFC USA, Miami Beach, FL; Allan Brayley, Flatiron, Broomfield, CO

The main spans of the US181 New Harbor Bridge expected to be built in Q1 2025 will replace the 66-year-old crossing over Corpus Christi, TX shipping channel. With a length of 3,289’, a central span of 1,661’, and a width under 149’, once complete, it will be one of the longest cable-stayed bridge in the USA, the longest precast segmental span and widest delta frame bridge in the world.

The construction engineering of such a structure called for special attention, particularly when considering the geometry control of the bridge and the site-specific wind hazard.
It culminated with the planning of the bridge deck closures.

There are four different closures on the bridge. Three are located on the back span side: temporary pier, intermediate pier, and transition pier closures. The last one is at the main span, connecting the two cantilevers together.
Each of these came with its own set of goals and constraints. With a relatively stiff superstructure, forcing alignment is generally inefficient, or comes at the expense of unintended locked-in loads. Hence, identifying the amount of tolerance in the various connecting elements was key.

Extensive coordination was required between the bridge EOR, contractor and the temporary works designer to ensure the sequencing of operations was agreed, and the interaction between the bridge and the temporary works was appropriately captured.

IBC 25-40: Transforming a Decommissioned Marine Corps Elevated Causeway System (ELCAS) for Versatile Construction Access Solutions
Houston Brown, Pennoni, Newark, DE; Ralph Farabaugh, R.E. Pierson Construction Co., Pilesgrove, NJ; Mike Postorivo, R.E. Pierson Construction Co., Pilesgrove, NJ; Christos Aloupis, Pennoni, Philadelphia, PA

Delaware River and Bay Authority (DRBA) and RE Pierson Construction (REP) are constructing a $90 Million Ship Collision Protection System to protect the Delaware Memorial Bridge, critical infrastructure for commerce and traveling public. Due to the lack of a sufficiently capable dock for crane operations to transport equipment and materials from shore to the site, the contractor elected to install a temporary pier. For this purpose, they employed an Elevated Causeway System (ELCAS), which was acquired from the Marine Corps following its decommissioning.

The ELCAS was originally created to provide logistical support for the Marine Corps and Joint Expeditionary Forces in challenging cargo transfer areas. It’s a modular system with standard ISO shipping container fittings, designed for rapid assembly using a “top down” method. The system, featuring airtight structural steel pontoons, includes a runway configuration and various pierhead arrangements, with 24-inch steel pipe piles for support, designed for specific loading needs.

To meet temporary works project specifications, Pennoni performed a detailed analysis throughout all construction stages, adhering to the AASHTO Guide Design Specifications for Bridge Temporary Works. Previous designs were reviewed to identify the critical checks, particularly for pile extraction where mud retention could overstress the pontoon system. To mitigate this, pipe piles were capped to prevent mud accumulation. Key design elements, including the connection plate assembly between pontoons and pile connection to pontoons, were evaluated. The ELCAS system was demonstrated to have adequate reserve capacity and has successfully supported a Manitowoc 777 crane in construction activities.

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Domestic Major Bridge Projects

Time: 1:30-5:00 PM

IBC 25-41: Reconnecting communities: How capping the I-35 will change Austin, Texas for generations to come
Kasian Warenycia, Arup, New York, NY; Luke Tarasuik, Arup, New York, NY

In recent years, the US has seen a significant trend toward innovative infrastructure renewal projects driven by the need to address aging infrastructure, the availability of federal investment through the Bipartisan Infrastructure Law, the adaptation of cities to meet the challenges of climate change, and the effort to address equity and justice in infrastructure planning. Many cities across the US are investigating the feasibility or have constructed similar capping projects such as the Gateway Arch National in St. Louis, Brooklyn-Queens Expressway in New York, Presidio Parkway in San Francisco, and ReThink Indianapolis I-65/I-70. Arup has been working with the City of Austin to develop the feasibility and concept design for a series of highway caps over I-35 as it passes through Downtown Austin. The planned upgrade will place the road below grade, creating the opportunity to cap over the highway and help reconnect the communities that have been historically divided by this complex infrastructure. The capping of the I-35 will provide up to 30 acres of space for new parkland and buildings above the highway. The cap structures, which consist of prestressed concrete I girders, are designed to take amenities including up to 2-story buildings with occupied roofs and up to 50ft tall shade trees in landscaped zones. The cap structures will be designed to take the heaviest loading throughout the programed zones to allow for changes to amenity space over the structures’ design life and adapting to the needs of future generations of Austin residents.

IBC 25-42: The Brent Spence Bridge Corridor Project – A New Ohio River Crossing and Approach Structures
AJ Cardini, AECOM, Boston, MA; Kyle McLemore, AECOM, Tampa, FL; Mark Wimer, AECOM, Akron, OH; Randy Thomas, Jacobs, Milwaukee, WI

The $3.6 billion Brent Spence Bridge Corridor Project will transform eight miles of interstate I-75/71 in Cincinnati, Ohio, and Covington, Kentucky. The project will reduce congestion, improve traffic flow and safety, and maintain a key regional and national transportation corridor. Lead designer AECOM and subconsultant Jacobs with contractor partners Walsh/Kokosing began work on this Progressive Design-Build project in 2023 under the direction of the Bi-State Management team (BSMT) comprised of ODOT and KYTC.

The existing Brent Spence Bridge, a double-decker truss built in the 1960’s, will be rehabilitated and will remain to carry local traffic. A new bridge, called the Brent Spence Companion Bridge (BSCB), which will carry 10 lanes of I-75/71 over the Ohio River, will be built immediately to the west of the existing bridge. Due to site width constraints, a double-decker bridge with 5 lanes per level was required. The development and selection process for the preferred alternative of this major span crossing will be discussed.

The Kentucky side structural work includes double-decker bridge approaches to both the existing Brent Spence Bridge and the new BSCB; as well as bridges at several interchanges. There are 22 total bridges, with length totaling approximately 7,000’. The Ohio side structural work also comprises double-decker bridge approaches to both the existing Brent Spence Bridge and the new BSCB, a complete reconfiguration and reconstruction of the multi-level I-75/I-71/US50 interchange, and grade separations through the Cincinnati downtown core, with 43 total bridges. Both sides approach spans will feature numerous steel triple-I-girder straddles.

IBC 25-43: Modernizing Lawrence to Bryn Mawr with Segmental Box Girders for the Chicago Transit Authority
Emily Hereford, Stantec, New York, NY; Ben Soule, Systra – International Bridge Technologies, San Diego, CA; Joe Kelvington, Stantec, Raleigh, NC; Kevin Buch, Walsh Fluor Design Build Team, Chicago, IL; Jay Lee, Stantec, Denver, CO

The Red and Purple Modernization (RPM) Phase One Project is the largest capital improvement in Chicago Transit Authority (CTA) history. It aims to replace, reconstruct, and modernize 10 miles of elevated track and support structures along Chicago’s busiest transit corridor, enhancing train speeds and capacity with a 100-year service life. A major portion of the project includes a 1.4-mile viaduct identified as the Lawrence to Bryn Mawr Modernization (LBMM).

Final LBMM design and construction advanced from an alternative technical concept (ATC) proposal to utilize precast post-tensioned segmental box girder spans to lower construction costs, reduce build time and foundation construction, and minimize maintenance. Design required complex 4-D analyses, including rail-structure as well as vehicular-structure interaction, and accommodated top-down construction.

The ATC permitted maintenance of CTA transit operations throughout construction through staged construction within an extremely narrow urban corridor. Modified top-down construction which employed a specialized launching gantry system supported on permanent bridge piers made staged construction possible.

Single column piers which make up the majority of LBMM substructures are designed to support box beam spans as well as temporary construction loads from the launching gantry system. Drilled shafts placed in clay soils support these piers. LBMM design also features removal of existing tracks and track embankments confined between parallel retaining walls. Removal of embankments and walls opens the space underneath the structure for community use and/or future development.

This presentation will focus on the unique challenges met by designers and the contractor as they executed construction of this complex project.

IBC 25-44: The wind design of the longest cable-stayed bridge in North America, the Gordie Howe International Bridge
Pierre-Olivier Dallaire, RWDI, Guelph, ON Canada; Zachary Taylor, RWDI, Guelph, ON Canada; Stoyan Stoyanoff, RWDI, Guelph, ON, Canada; Mark Istvan, RWDI, Guelph, ON, Canada; Barry Chung, AECOM, Tampa, FL

In 2025, the Gordie Howe International Bridge will be opened to traffic and will become the longest cabled-stayed bridge in North America. This impressive structure will serve as a vital economic link between Canada and the United States. With a main span of 853 m, the bridge is an important engineering achievement that required in-depth technical understanding of multiple aspects such as its wind performance and resiliency to the local climate. One aspect that also makes this structure quite unique is the traffic that one can expect since it is an international crossing.

Based on the extensive wind design work that was performed for this bridge, three main topics will be covered in this presentation:

• Optimizing the deck cross-section selection with considerations to aerodynamic stability, presence of heavy traffic, fencing, risk of icing, structural design, and acoustic performance.
• Understanding the wind-induced buffeting response of the bridge for various wind events and its impact on the detailed design of lock-up devices (LUDs) for wind action.
• Evaluate the performance of the stay dampers against wind-induced vibrations and quantify the demands for structural design.

These various studies should be considered as unique and were deployed to assist in the detailed evaluation of this bridge and represent an important advancement for the field of wind engineering. Innovative simulation approaches, design findings and conclusions will be presented and discussed.

IBC 25-45: Design and Construction of 3-Tower 4-Span Cable-stayed Mississippi River Bridge
Martin Furrer, Parsons, Chicago, IL; Greg Hasbrouck, Parsons, Chicago, IL; Vincent Gastoni, Parsons, Minneapolis, MN; Mitch Johnson, Ames Corporation, Burnsville, MN; Stacy McMillan, Missouri DOT, Jefferson City, MO

Missouri and Illinois DOTs looked to replace the Mississippi river crossing at Chester, a narrow truss at end of its useful life, using a best-value design-build procurement method.
Major site challenges:
• very large vessel allision loads for any pier located within navigable waters,
• Coast Guard requires 800 ft main with 500 ft auxiliary or single 1050 ft navigational channel,
• high seismic demands (proximity to New Madrid Fault) and large variations in depth to rock across the river,
• Illinois bank is occupied by state route and wide Union Pacific railroad mainline ROW,
• site is located near airport limiting structure height,
• significant river level fluctuations, impacting ability to build bridge in about 2 years.
Challenges are met by a four-span, three-tower cable-stayed bridge solution with two 885 ft main spans. A reinforced concrete deck of full depth modular panels with an overlay is supported by transverse steel floor beams and longitudinal steel edge girders. Stay-cables connect to exterior of edge girders at 45 ft intervals and anchored in towers with steel anchor boxes. The three towers are founded on either driven pipe piles or drilled shafts and consist of two free-standing, vertical legs each.
The presentation will discuss innovative solutions deployed to maximize technical score and minimize construction duration and cost, including post-tensioning-free deck, maximized tower rebar preassembly, bearing restraint solutions employed to best respond to the seismic demands, and the corrosion protection enhancements included to ensure a low-maintenance, 100-plus year service life for the crossing.

IBC 25-46: Rebuilding the Lynchpin of American Commerce – the new I-70 Rocheport Bridge
Greg Hasbrouck, Parsons, Chicago, IL

Interstate 70 is an artery of commerce serving the heart of national and regional distribution and commodity flows connecting Missouri’s largest cities. Each year, approximately 100 million tons of freight, worth more than $154 billion, is carried across I-70 in Missouri. Carrying 12.5 million vehicles per year, including over 3.6 million freight trucks travelling across the United States, the I-70 Bridge over the Missouri River at Rocheport has been called the “lynchpin of America.”

Built in 1960, the current crossing is a single through truss with steel plate girder approaches that carries two lanes of traffic in each direction and is functionally obsolete and structurally deficient. On July 1, 2021, the Missouri Highway Transportation Commission awarded a team comprised of Lunda Construction and Parsons a $220 million design-build project to replace the bridge. The project expands an existing 2.65 mile stretch of the I-70 corridor from four lanes to six lanes, provides new twin 3,120-foot-long bridges with a 490-foot navigation span across the Missouri River.

Using twin bridges was a key factor in alleviating MoDOT’s concerns about traffic delays during construction and minimizing the environmental footprint, as well as providing redundancy of structures and an overall best value. Upon completion, each bridge will be three lanes with room for future expansion. Each bridge consists of a 5-span steel plate girder unit and two 5-span PPCB approach units with approach spans founded on large-diameter pile bents and river piers on a single line of large-diameter drilled shaft socketed into rock.

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Repair and Retrofit Projects

Time: 1:30-5:00 PM

IBC 25-47: I-35 Haunched Slab Bridge Raises
Natalie McCombs, P.E., S.E., HNTB Corporation, Kansas City, MO; Joe Sturgeon, HNTB Corporation, Kansas City, MO; Justin Frasier, Wildcat Companies, Topeka, KS; John Jackson, P.E., Fulcrum Construction Solutions, Oklahoma City, OK

The Oklahoma Department of Transportation was interested in increasing the vertical clearance under several bridges along the I-35 corridor in northern Oklahoma. The plans to raise the 4-span haunched slab bridges provided a detailed option for competitive bidding while allowing the contractor’s means and methods to be implemented. The bridge type has an impact on how the bridge will be raised. A typical beam bridge has bearings that allow rotation during construction and operating conditions. With these bridges being haunched slab bridges, raising these bridges had different risks and behavior. The presentation will cover the process from design approach and special considerations to the construction implementation and innovations. Lessons learned will be discussed along the way.

IBC 25-48: Tying Two Nonredundant Steel Two-Girder Bridges Together with Floorbeams to Create a Single Bridge
John Sloan, AECOM, Raleigh, NC; Tim Sherrill, North Carolina DOT, Raleigh, NC; Ed Zhou, AECOM, Germantown, MD; Mark Guzda, AECOM, Mechanicsburg, PA

The I-26 Green River Bridges were built in 1968, and they consisted of parallel nonredundant steel tension member 2-girder steel structures with a main unit having spans of 260’-330’-260’. This project consisted of a strengthening and rehabilitation of the bridges that included adding cover plates, adding stiffeners, replacing the existing lightweight concrete decks with a new single lightweight concrete deck, adding shear studs to the girder and stringer top flanges to make them composite, tying the two bridges together with floorbeams to make them a single structure, and widening the deck. The project team has provided a feasibility study, final design, design phase load testing, and construction phase services that include the instrumentation and monitoring of the structure. All steel rehabilitation and strengthening work is complete, two phases of deck pours are complete, and the final phase of the deck replacement work is anticipated to be complete in the spring of 2025.

IBC 25-49: James River Bridge – Main and Auxiliary Wire Rope Replacement
Austin Holub, PCL Construction, Inc., Tampa, FL

The James River Bridge is a vertical lift bridge carrying US Route 17 over the James River between Isle of Wight and Newport News, VA. The bridge is owned by the Virginia Department of Transportation. The movable span of the vertical lift bridge is 415 feet long, weighs approximately 3,360,000 lbs, and is lifted by 80, 2-1/8 inch wire ropes.

The main counterweight ropes are original to the bridge at over 41 years old, surpassing their predicted lifespan. VDOT selected the option of two, 100-hour outages during which 40 ropes (one tower) would be replaced per outage.

To expedite the replacement of the wire ropes, VDOT chose to procure the ropes, take-ups, and associated hardware prior to advertising the construction portion of the project. While the ropes, take-ups, and hardware were being fabricated, VDOT awarded PCL the contract to perform the replacement. From the onset of the project, PCL actively collaborated with VDOT and HDR to develop plans to execute the replacement of ropes within the allowable time constraints.

The process for replacing the ropes utilized four, 400-ton and two, 50-ton hydraulic jacks for lifting the movable span, while air winches were utilized for removing and installing the new ropes over the sheaves. The outages occurred in January and February of 2024. While challenges were expected to occur, the project team successfully constructed the project due to the proactive steps taken by PCL, HDR, and VDOT during the planning and preparation phases.

IBC 25-50: The US 50-Blue Mesa Bridge Emergency Repair
Nathan Schaeffer, P.E., Michael Baker International, Moon Township, PA; Alex Gioseffi, P.E., Kiewit, Woodcliff Lake, NJ; Keely Matson, P.E., Michael Baker International, Lakewood, CO; Richard Schoedel, P.E., Michael Baker International, Moon Township, PA; Jacob O’Brien, P.E.,
Colorado DOT, Denver, CO

In April 2024, while conducting the Federal Highway Administration (FHWA) required non-destructive evaluation of Non-Redundant Steel Tension Member (NSTM) bridges, the Colorado DOT discovered two partial fractures at the shop butt welds along the bottom tension flange of the US-50 Blue Mesa Reservoir Bridge near Gunnison, Colorado. The Colorado Department of Transportation (CDOT) took immediate action in closing the structure to prevent bridge failure; however, the closure of the bridge resulted in a lengthy six-hour detour for local motorists. Emergency work with CMGC industry partners Kiewit Infrastructure Company and Michael Baker International began immediately to identify and implement solutions to repair or replace the critical bridge, as well as a second crossing of the reservoir of nearly identical construction. Thorough non-destructive testing began and ultimately revealed numerous indications throughout many of the structure’s 118 tension butt welds. Widespread transverse hydrogen cracking of the girders’ web-to-flange welds was also discovered. These defects led to the eventual decision to implement global plating of the bottom tension flanges to prevent collapse if any of the defects were to result in a fracture. A novel approach to deter the propagation of cracking through the web was also implemented, acting in conjunction with the flange plating to provide a fully redundant system. Significant weight was added to the bridge necessitating the use of A514 (100 ksi) for plating steel and thin ¾” polyester polymer concrete overlay to keep the weight within manageable limits.

IBC 25-51: Retrofitting for Longevity: Modification of In-Service Steel Box Girders to Facilitate Bridge Inspection and Maintenance
Y. Edward Zhou, AECOM, Germantown, MD; Brett McElwain, AECOM, Hunt Valley, MD; Eric Johnson, Pennoni, Mechanicsburg, PA; Ruel Sabellano, Maryland Transportation Authority, Baltimore, MD; Hua Sheng He, Maryland Transportation Authority, Baltimore, MD

The MDTA owns 19 steel box girder bridges constructed in the 1970’s with no access provided to the spaces beyond the ends of continuous-span units at both abutments and certain piers for each bridge. Over time, some girder ends have experienced significant corrosion-induced section losses in the areas surrounding bridge expansion joints. To facilitate bridge management activities in these areas including inspection, painting, repairs, and various maintenance actions, it is highly desirable or necessary to add access holes in the box girder end diaphragms. However, the end diaphragm above box girder bearings is a primary structural element and is highly loaded in shear between the bearing and box girder webs. This paper discusses: 1) an analysis procedure for determining the access hole layout and dimensions to maintain box girder integrity while meeting bridge management needs; 2) checking against pertinent AASHTO bridge design requirements; 3) the construction process of a recently completed pilot project on two curved bridges of 13 spans and 7 spans, and 4) issues encountered and lessons learned from construction after successful completion. The analysis procedure employed 3D finite element modeling to assess changes of buckling capacity due to added holes and maximum stresses surrounding the new holes. Successful completion of the pilot program required well-executed coordination among the owner, design team, and contractor for efforts including field visits to confirm as-built and deteriorated conditions, several iterations of structural analysis, and contract documents.

IBC 25-52: Heat Straightening Practices
Ronnie Medlock, High Steel Structures, LLC, Lancaster, PA; David McQuaid, DLMcQuaid and Associates, Upper St. Clair, PA

Heat straightening is an effective tool for straightening steel bridge members, particularly in remediation of bridge hits. This paper will describe heat straightening practice, including

– limits on what can and cannot be heat straightened from a practical point of view;
– basic heat straightening steps;
– using heat in conjunction with pressure;
– concerns about the blue brittle range of steel
– temperature limits based on the iron-carbon phase diagram
– temperature measurement;
– considerations for cold bending; and
– resources available for engineers.

Examples of bridge straightening will be featured.

This abstract is anticipated to align with a heat straightening demonstration during the IBC.

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Rail Projects

Time: 1:30-4:30 PM

 IBC 25-53: Recommendations for Numerical Modeling for Rail Structure Interaction Analysis
John Lobo, HDR, Denver, CO; Ying Tan, Ph.D., HDR

Rail-structure interaction analysis (RSI) is very important for the design of transit bridges and viaducts carrying continuous welded rail. The rail and its supporting structures are subject to different temperature loads and usually have different freedom of movement. The bridge and rail system are connected and this creates complex, non-linear interaction between the two systems. RSI analysis is prescribed by most transit agencies in North America, especially in case of long elevated guideway or bridges with curvature and for elevated guideway with direct fixation (non-ballasted) track. There are few guidelines on numerical modeling of the system and the basis of the small number of recommendations is not clear. There is a no consensus in the USA regarding which parameters will control analysis or how these parameters should be defined in the analytical models. This study evaluates the impact of four necessary and key model inputs, viz. bridge curvature, spring behavior, rail fastener spacing and fastener restraint force. The impacts of these parameters are studied through parametric analysis, keeping all other factors constant and examining the effects on axial rail stress, rail break gap, substructure forces and superstructure stresses. This study provides guidance to transit structure designers to determine the best method for modeling their structure in a rational manner.

IBC 25-54: Railroad Bridge Live Load Impact Versus Train Speed: Field Test Evaluation
David Jacobs, University of Hartford, Niantic, CT; Suvash Dhakal, Connecticut DOT, Newington, CT

The rating section of the American Railway Engineering and Maintenance of Way Association’s Manual for Railway Engineering gives a formula for a curvilinear reduction in the design impact factor for rating purposes based on train speed below 60 mph (96.6 km/h). A novel study to measure the actual change in dynamic impact force from modern passenger equipment as a function of train speed was conducted by measuring the deflections, strains and accelerations of several truss and floor system members from live loads on the structure; a 118-year-old through truss bridge. Data were recorded from two different types of electric passenger trains with speeds ranging from approximately 5 to 40 mph (8.1 to 64.4 km/h). Our test results indicate that the impact reduction relationship relative to speed for the type of vehicles used in our study, is significantly less than from that called for by the Manual’s impact reduction formula. This result could have significant ramifications for extending the service life of existing, very old railroad bridges, where the predominant live load is passenger equipment, such as on the Northeast Rail Corridor between Washington, D.C. and Boston, Mass.

IBC 25-55: Park Avenue Viaduct Replacement – Analysis and Design, Pushing the Envelopes of Accelerated Construction
Firooz Panah, AECOM, Boston, MA; Latif Ebrahimnejad, AECOM, Boston, MA; Ebad Honarvar, AECOM, New York, NY; Chris Cucco, AECOM,Boston, MA; Pradeep Maurya, AECOM, Boston, MA

Located in New York, Park Avenue Viaduct is an extremely active line carrying four tracks of Metro North Rail (MNR) trains from Grand Central to points North through Harlem. MTA C&D embarked on replacing this aging structure using Design-Build (D-B) delivery method. A team consisting of Halmar International as contractor and AECOM as design consultant was selected in December 2022 to deliver this project.
While the viaduct is very long, Phase 1 focuses on the replacement of 32 spans, each 65’ long, two tracks at a time. The 120-year-old viaduct consists of three through steel girders framed into steel columns. The D-B team can replace two tracks during the weekends only, while the other two are active.
To accomplish this, the D-B team used an integrated system of Prefabricated Bridge Units (PBUs) consisting of steel plate girders and full depth precast concrete deck. For the method of construction, Halmar decided to use two 200-tons mobile portal gantries for the demolition of the existing bridge and the installation of the proposed PBU’s.
The foundations and piers were constructed under the exiting viaduct. Four spans of the superstructure were replaced during the weekends. To save time, the rail plinths, track fasteners, and third rail were installed in advance before erection of the PBUs. The paper will also discuss analytical methods notably track-structure interaction, as well as unique details developed to stabilize the existing viaduct in the longitudinal and transverse directions during all stages of the construction.

IBC 25-56: Design and Construction of a Steel Gussetless Truss Bridge for Railroad Application
Juan Alfonso, P.E., HNTB, Parsippany, NJ; Xin Li, P.E., HNTB Corporation, Parsippany, NJ; Ayman Bataineh, P.E., HNTB Corporation, Parsippany, NJ; Gregory Romano, P.E., HNTB Corporation, Parsippany, NJ

The existing NJ Transit Structure 2.18 is a two-span, open deck girder bridge carrying a single curved track over West Side Avenue in Jersey City, NJ. The low clearance beneath the existing superstructure and pier arrangement requires replacing the bridge to accommodate the proposed NJDOT New Road alignment and profile. The replacement bridge alignment is to the inside of the existing track, which minimizes track outages and enhances safety during construction. However, the longer span of the replacement bridge and horizontally curved track layout necessitated a reevaluation of traditional railroad bridge designs. Through discussions with project stakeholders, a 160-foot-long single-span steel gussetless truss was selected as the preferred replacement alternative.

The innovative gussetless truss system features prefabricated built-up truss joints comprising a web plate welded to curved, cold-bent flange plates. The gussetless design eliminates the traditional gusset plate connection, which is prone to deterioration and is hard to inspect. The truss top/bottom chords and diagonals consist of fabricated I-sections similar to plate girders. Diagonals are connected to gussetless joints using double-shear field-spliced bolted connections.

The bottom chord, which also functions as a beam in strong-axis bending, enables elimination of stringers by using intermediate floorbeams between truss joints. Additionally, the gussetless joint is a moment-resisting connection, enhancing the structural system redundancy compared to traditional truss constructions, particularly when combined with the orientation of truss bottom chords in strong axis bending. As a result of the innovations, the bridge superstructure becomes easier to construct, inspect, and maintain.

IBC 25-57: HLMR Disk Bearings Applications of on Light Rail Structures
Ronald Watson, R. J. Watson, Inc., East Amherst, NY; Jay Conklin, R. J. Watson, Inc., Alden, NY; Zachary Searer, R. J. Watson, Inc., Alden, NY

High Load Multirotational (HLMR) Disk Bearings have long been used on Highway Bridges dating back 50 Years now with an outstanding performance record on all types of structures. One of the common applications is on light rail bridges in North America. One interesting User study is on the Washington Metropolitan Area Transit Authority (WMATA) System where they have used HLMR Disk Bearings on the new Silver Line Concrete Bridges and have also used disk bearings to retrofit steel plate girder bridges on the Orange Line replacing failed bronze spherical and steel rocker bearings.
This paper will focus on the WMATA applications and other users of disk bearings on different types of light rail bridges. Design and Testing requirements will also be looked at with a goal of educating engineers on the potential for this innovative and reliable device.

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