Project Name: I-84/Route 2 Bridge Bundle, CT
Owner: Connecticut DOT
Contractor: The Middlesex Corporation
CTDOT’s second ever DB contract, the I-84/Route 2 Bridge Bundle project scope included the removal and replacement of four bridge superstructures, three in East Hartford and one in Willington. The new bridges incorporated both traditional cast-in-place concrete construction and innovative Accelerated Bridge Construction (ABC) techniques. The expedited schedule of the project required two bridges to be completed within single-phase, 60-day construction windows, while the other two bridges were completed in two-phase 180-day periods.
The innovative design and construction use of Prefabricated Bridge Units (PBU’s) and Geosynthetic Reinforced Soil – Integrated Bridge Systems (GRS-IBS) as ABC techniques were instrumental in meeting the required 60-day milestones for two of the bridges in East Hartford. Additionally, prefabricating the structural steel and superstructure components of each phase of the 180-day bridges earned the project a four-week early completion bonus.
Value engineering and the ATC process during the proposal phase provided CTDOT with a project 9% below their contract budget and completed with a “zero-claim” status. Additional value was provided to CTDOT in that the intent of the contract was to replace only the superstructure of each bridge, supporting them on the existing 55-year old substructures. Through construction of the new GRS-IBS abutments on two of the four bridges, and conversion from three spans to single-span bridges, the end result was entirely new structures with a 75-year design life, along with additional horizontal clearance below each bridge for future widening of I-84 and enhanced traffic safety. The Middlesex Team constructed a project for CDOT at a lower cost and with more than what they had asked for. CTDOT’s second design-build was definitely a “Best Value” for the citizens of the State.