O&G replaced the superstructure of the Route 175 bridge over AMTRAK utilizing an Accelerated Bridge Construction (ABC) technique, one of the first ABC projects completed in the state. The bridge was largely prefabricated offsite, then installed during short windows of time to reduce the impact on motorists, AMTRAK service on the rail line beneath the bridge, and accelerate overall time to completion.
Seven, 105-foot-long, Prefabricated Bridge Units (PBUs) replaced 19 aging concrete box beams and were constructed 100 yards from where they were installed. More than 75 personnel from eight companies worked for 50 continuous hours according to a meticulously sequenced and rehearsed plan to install the PBUs. By constructing the bridge nearby, and through diligent planning and preparations, the old bridge was removed, and the new bridge was installed over two weekend shutdowns, finishing within the 56-hour windows allotted for the work, six hours ahead of the Monday morning commute.
Throughout this project, numerous instances of collaboration helped arrive at better, faster and lower-cost solutions to construction challenges, such as:
• Modifying the design of the sheet pile earth retaining system, saving approximately $60,000,
• Modification of the precast approach slabs to a cast-in-place slab providing a better-finished product for the owner,
• Self-Fabrication of the new deck slab segments on-site allowing for timely and cost-effective measures for construction, QA/QC oversight and control, and unencumbered delivery of the finished product.
Critical to the success of this project was the coordinated effort on O&G’s part to involve all stakeholders including CTDOT, the Town of Newington, utility companies, subcontractors, and material suppliers in a partnering process to overcome all construction-related challenges this project faced.”