US 50 Bridge Improvements

Location

Lawrence County, Illinois

 

Client

Illinois Department of Transportation - District 7

 

Services provided

Structural engineering

Surveying

 

Project overview

Phase II engineering services were required for the superstructure rehabilitation of 10 bridges on U.S. Route 50 in Lawrence County, IL. The existing pre-cast pre-stressed deck beams were severely deteriorating, creating lane closures and potential detours. The superstructure replacement would be accomplished in two phases in consecutive construction seasons.

 

Approach

The Illinois Department of Transportation (IDOT) District 7 partnered with STS for structural, civil engineering and surveying services on the $10 million improvement project. During the course of the project, STS provided surveys for the roadways and bridges; type, size and location studies for the two construction contracts; construction plans for the superstructure replacement; special provisions and substructure repair plans; and traffic control plans and detour plans for the two construction phases. In addition, STS served as the prime consultant overseeing and reviewing the work of a minority business enterprise subconsultant designing two superstructure replacements.

 

The first phase on the eastbound section included three pre-cast prestressed deck beam bridges – one 328-foot, five-span bridge, one 202-foot four-span bridge, and one 453-foot seven-span bridge. The contract also included one 206-foot three-span steel beam and cast-in-place concrete superstructure. The second phase on the westbound section included four westbound structures, plus two 209-foot five-span pre-cast pre-stressed deck beam bridges constructed in stages to maintain traffic.

 

During each phase, traffic was detoured on local roads to allow the most efficient construction. STS provided detour plans and signing to handle the traffic.

 

Client benefits

• The studies and plans were delivered by STS’ experienced team on schedule, preventing costly construction delays.
• The bridges were successfully constructed under budget.