Storrow Drive Interchange/Tunnels
Storrow Drive, a parkway along the Charles River in Boston, carries more than 100,000 vehicles per day. The tunnels provide access to city streets, and are constructed of reinforced concrete sections with concrete-slab roofs that are supported by wide flange steel beams spanning the roadway. Upon discovery of severe cracking of the overhead roof slab and corrosion of the supporting steel beams, the client needed a detailed condition survey, structural review, and design of emergency and permanent repairs. SGH and our team of subconsultants designed long-term structural modifications to address deficiencies in the tunnel roofs, which carry traffic, and in the walls and invert slabs; designed improvements in lighting and landscaping; addressed traffic-disruption mitigation during reconstruction; and designed temporary roads for traffic diversion. We also performed load tests, long-term instrumented monitoring, and bridge ratings of the tunnel roofs.