Route 1 Viaduct Reconstruction (Chelsea Curves)

Chelsea, MA

The Chelsea portion of Route 1 is one of Massachusetts's most heavily traveled viaducts. Reducing the road to two lanes in each direction during the reconstruction required as many accelerated techniques as possible. The Skanska McCourt JV started this process by modeling the entire structure through laser scanning and identifying any conflicts ahead of time. The early identification of these conflicts allowed redesign before the fabrication of any precast bridge units and the construction of the substructure. The solution to these conflicts (developed by a joint MassDOT, HNTB & Skanska McCourt effort) was to decouple the steel stringers from the existing steel and tie them directly to the corbels on the substructure.

This project includes cleaning, painting, and encasing each steel support beam in a concrete column and corbel. The pairing of the superstructure support beams with sister beams on either side is set on the corbels. They then placed cast-in-place frames or precast bridge units on the sister beams and built the road from there. Edge or centerline barriers were then placed, and the entire structure was paved. Several parking lots were reconstructed underneath the viaduct, including paving and drainage.

An innovative redesign of the complex traffic control plan allowed Skanska McCourt to eliminate several stages, allowed us to work through the winter, and destroyed the potential for significant traffic delays caused by single enclosed traffic lanes.