I-44 over Jefferson Avenue – Eastbound & Westbound
CDI provided professional structural engineering services for MoDOT’s I-44 twin bridge replacement project over Jefferson Avenue. The structural scope of work included the development of a preliminary bridge layout that accommodated a cost-saving, shorter-span structure using mechanically stabilized earth (MSE) retaining walls, lightweight fill, and a long-span steel plate girder.
The new bridges provide the required minimum vertical clearance for Jefferson Avenue, as well as the sidewalks along either side of Jefferson Avenue throughout this urban section. The bridge is a 132-foot span on pile-supported integral end bents. The existing intermediate bent piles at bents two and four were removed to allow for the installation of the proposed MSE wall. Lightweight fill was utilized to eliminate the use of ground improvements. This construction method eliminated the coordination of ground improvements throughout construction and the associated delegated design. Using the lightweight fill decreased the construction schedule by removing a ground improvement sub-contractor and ground improvement designer. The large lightweight fill lifts were installed quickly to bring the reinforced MSE wall embankment to the roadway grade.