AIE is providing final design plans, specifications, and construction cost estimates for Bridge No. 00326, U.S. Route 1 over Metro-North Railroad in Stratford, CT. This is a three-span concrete-encased, riveted steel plate girder structure carrying four lanes of U.S. Route 1 traffic over four active Metro-North Railroad lines.

AIE’s services also include the design of the approaches, maintenance and protection of traffic, hydraulic analysis, and storm sewer design. The structure is considered structurally deficient and functionally obsolete and will be replaced in its entirety. The replacement bridge will be a 120 ft. long single-span structure consisting of an 8 in. thick composite concrete deck on weathering steel plate girders.

The replacement bridge will be widened to accommodate roadway shoulders and sidewalks on both sides. Additionally, the bridge will be elevated to achieve the minimum vertical clearance requirements over electrified railroads. A solid barrier fence topped with a curved chain-link protective fence will be installed on parapets over the railroad tracks to satisfy safety requirements.

The maintenance and protection of traffic for the bridge construction shall consist of four construction stages. Stage 1 allows for the construction of the new Geosynthetic Reinforced Soil (GSRS) abutments and wingwalls below spans 1 and 3 to the vertical limits feasible while traffic is maintained on top of the bridge. In its final completed condition, the closely spaced reinforcement and granular soil will create an efficient composite material that is internally stable and capable of carrying significantly higher bridge loads.

Additionally, the GSRS substructure will create a seamless and smooth transition between the bridge and approach roadway without joints. Stages 2 and 3 allow for the partial demolition and reconstruction of the superstructure by reducing U.S. Route 1 traffic from four lanes to two lanes (one lane in each direction). Stage 4 allows for the construction of the north sidewalk and placement of the final wearing surface on the bridge.