This truss-span bridge is 1,280 ft. long with 8 spans including 320-ft. truss span, 50 ft. high and 60 ft. wide.

The Church Street South Extension project provided a new steel truss bridge over the New Haven Interlocking and Rail Yard, directly linking downtown New Haven and the Long Wharf and waterfront areas. To minimize disruption in the rail yard and improve work-zone safety for a crew working over active rail lines, ConnDot required that this portion of the bridge be completed in a single weekend night.

The 320-ft long, 850 ton prefabricated truss center span was constructed over several months next to the active rail lines and then lifted into place on an early Sunday morning in May 2003 by a single high-capacity crane owned by Lampson International LLC. The crane, which required more than four weeks to assemble, lifted the entire truss span more the 65 ft. and moved it more than 100 ft. to its final position. Specifying prefabrication saved ConnDOT about a year on its overall contract time and at least $1.1 million. Prefabrication of the center span greatly improved constructability for O&G Industries; the center span could not have been built during the limited working hours allowed by the rail yard. Using prefabrication on this project avoided closure of 4 tracks during bridge construction.

The 115' single span butted box precast elements were placed on an entirely precast substructure. Nine precast footings pieces were leveled using leveling screws and then grouted in place. Full moment connections were created between wing and abutment stems to precast footings by means of grouted splice sleeves. The connections were cured overnight, , the substructure was backfilled and the butted box beams were placed. The joints between beams were grouted and transversely post-tensioned. Finally, the deck surface was membraned and paved, and rail was placed. It took less than eight days from the time the first precast footing was lifted from the trailer to the time when the bridge was opened to traffic.

The contract included a 14 day requirement to open bridge to traffic with an incentive/disincentive of $5,000/day. The contractor received a $30,000 incentive bonus.

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The Lions' Gate Suspension Bridge arches 60 meters above Vancouver's First Narrows, connecting communities on both sides of Burrard Inlet. More than 60 years of constant traffic and corrosive deicing treatments left the steel and concrete roadway in need of improvements. A distinguished landmark, it has average daily traffic of between 60,000 and 70,000 vehicles.

Beginning in 1999, a rehabilitation project included replacement of the three-lane bridge deck and trusses encompassing widened lanes for traffic, widened sidewalks for cyclists and pedestrians, and seismic strengthening, as well as a complete upgrade of the traffic control system and lighting. The deck and trusses were replaced simultaneously while allowing traffic to use the bridge during replacement. Most of the reconstruction occurred during 10-hour shifts at night. Individual deck sections between 10 and 20 meters long were cut away and lowered with a jacking traveler (a gantry-like platform that attached directly to the suspenders of the bridge) to a waiting barge, and the replacement section was lifted into place. When assembled on the bridge, each section was connected to its neighboring section with more than 700 high-strength steel bolts. The first of 54 sections was replaced the weekend of September 9 and 10, 2000, and the final one was replaced the weekend of September 29 and 30, 2001.

The Maritime Off-Ramp at the intersection of I-80 and I-880 in Oakland, North America's first curved welded steel orthogonal isotropic bridge, provides access to the Port of Oakland through a U-turn from westbound I-80. The ramp is 2,356 ft long and has a 250-ft radius horseshoe shape. The California Department of Transportation (Caltrans) chose steel bridges to minimize traffic delays during bridge erection. Designers selected a closed cell structure for the horseshoe shape of the bridge as the most economical shape to resist torsional forces. The substructure includes reinforced concrete "T" bents with a single column with spiral reinforcing ties. Two special bearings connect the superstructure to each "T" bent.

The contractor fabricated 13 full-bridge-width orthogonal isotropic sections 7 ft 0 in deep by 35 ft 6 in wide up to 37 ft 6 in wide, with lengths ranging from 123 to 219 ft per section. All sections shipped with a steel orthogonal isotropic deck and with installed steel barrier rails. All fabricated steel totaled 5,014 tons.

Installation included special heavy-lift hydraulic platforms to move the bridge sections. Each of the 13 bridge sections was moved three times: from the fabrication facility to the barge, from the barge to the staging area beside the freeway, and from the staging area into its final location. The sections were staged on the east side of the freeway and crossed over during night erection during a 10-hr window beginning at midnight on a Saturday. The contractor faced stiff fines for each minute exceeding the time limit. Installation of three of the sections required closing half of the freeway lanes, below which approximately 500,000 vehicles cross per day. The segment over the westbound lanes was erected around midnight on one Saturday night, and the segment over the eastbound lanes was erected the following Saturday night.

Unique seismic detailing includes use of rubber dock fenders as seismic shock absorbers to reduce forces between completed bridge sections. Poly-tetra-fluoro-ethylene (PTFE) spherical bearings allow for rotation and expansion of members and can resist high lateral forces, including seismic forces. A central shear key provides additional lateral capacity.

This precast superstructure system with precast caps hells and piles includes 2 bridges 3,624 ft. and 2,843 ft. long and 44 ft. wide.

These 1956 bridges connect Marin and Contra Costa Counties in California. When heavy traffic and exposure to the marine environment necessitated replacement of the existing structures on the same alignments, the California Department of Transportation selected prefabrication. Allowing two lanes of traffic on both structures at all times during the day, the construction sequence closes one structure for 10 hours maximum at night. Crews install new piles outside the travel lanes of the existing bridge, install new precast prestressed bent cap shells on the piles, and pour concrete and then prestress the caps. Then crews start from the abutment using a barge-mounted crane to sequentially replace the superstructure. Two spans totaling 100 ft of existing superstructure are lifted out, and a new span is installed. Crews then install a 25-ft transition span to close the offset between new and old bents, and by morning traffic is running again. After installing four new spans, crews stress them together to make a 400-ft. continuous unit. Work on the westbound bridge will complete in Fall 2004, and work on the eastbound bridge will complete in Spring 2005.

This project uses 500-ton 100-ft precast superstructure system, precast prestressed cap shells, and piles. The use of prefabrication provided the California Department of Transportation with a new bridge that meets seismic codes with minimal traffic disruption. By fabricating off site, Tutor Saliba/Koch/Tidewater JV was better able to control quality and safety. Prefabrication enables users to access the bridge constantly, with limited disruption only at night.

This single-span bridge 69 ft. long and 32 ft. 8 in. wide has a concrete deck on steel girders.

The superstructure of the Richville Road Bridge in the Town of Manchester, Vermont, was in poor condition, but the existing abutments were in good enough shape to be reused with only minimal repairs. The Town limited bridge closure time to 14 days and then compared chose bridge prefabrication after comparing costs.

Bridge designers chose total superstructure prefabrication with the Inverset System^TM constructed off-site and transported to the site on trucks and lifted into place by a crane. Each of three prefabricated units consisted of two rolled beams with a precast reinforced concrete bridge deck. In place, the three units provided a complete superstructure except for the sheet membrane, paving, curb, and railing. Richville Road was closed for only the specified 14 days.

Use of total superstructure prefabrication saved the Town of Manchester approximately $20,000 over conventional construction plus a temporary bridge. Use of prefabrication enabled Dubois & King, Inc., to meet the Town of Manchester's 14-day closure requirement. In addition, the contractor received the American Consulting Engineers Council of Vermont's 2001 Grand Award for Engineering Excellence in Transportation for design of the bridge. Because of the prefabrication, bridge users avoided a lengthy detour with its resulting traffic disruption, travel costs, and time delays.

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This bridge with 3 spans (111-ft. center span) is a steel through truss in the city center.

Part of a large project to rebuild Chicago's Wacker Drive involved rebuilding an 1899 steel bridge for the Chicago Transit Authority's elevated trains. The original specification required rebuilding the bridge in section on weekends in one month; however, the bridge owner approved the contractor's value-engineering proposal to pre-build the bridge and then moved it into position over a single weekend. The center span was constructed near the site and moved on a special hydraulic carrier about 75 ft. west and 5 ft. north, where it was placed on new foundations and connected to two shorter spans on either side. In spite of stiff contractual penalties for any delay ($1,000/minute), work was completed over a weekend in May 2002 with 2 hours to spare.

The 425-ton, 111 ft. long and 25 ft. high center-span superstructure was prefabricated.

Chicago Transit Authority (CTA) avoided significant disruption to travelers commuting into the city from the north. CTA would have had to provide additional, costly shuttle services. Prefabrication allowed Walsh Construction to operate in a more controlled environment and to avoid the major shoring effort that would have accompanied rebuilding the existing structure while keeping it open for weekday traffic, thus limiting company liability for financial penalties. The use of prefabrication reduced disruption to vehicle drivers from 6 months to a single weekend; it reduced disruption to transit users from four to six weekends to a single weekend.