Initially built in the 1960s, the I-270 North corridor now carries over 140,000 daily. The corridor serves as a primary route for commercial vehicle traffic around St. Louis and is designated on both the National Highway Freight and Strategic Highway Networks. MoDOT is in the process of making improvements to the corridor, including rehabilitations to the pavement, bridge reconstruction, improved traffic operations, geometrics, and safety, improved accessibility for transit, bicycles, and pedestrians, and improvements to interchanges and outer roads.
CDI provided professional structural engineering and civil engineering services for the I-270 North Design-Build project as a member of the PARSONS team for the Missouri Department of Transportation.
The structural scope of work included the design of replacement bridges for northbound and southbound US 67 over I-270. Each of the bridges incorporated critical design elements in the foundations and superstructure resulting in a reduced construction schedule. CDI completed the northbound bridge design within four months of the notice to proceed, and the southbound bridge was completed in the following four months.
CDI also provided additional civil and structural services to CBB for this project. Civil services included an inventory of existing ground-mounted signs, design and plan production for ground-mounted signs, overhead sign cross-sections to aid CBB in their development of overhead sign details, weekly project task force coordination meetings, project review comment response and resolution, project management, administration, and invoicing for ground mount signing and overhead structure. Structural design services encompassed the foundation and support framing design and plans for non-standard MoDOT sign structures, which included electronic message boards and CCTV poles. The scope of work was completed within scheduled segments but on an aggressive schedule. CDI generated base sheets that were incorporated into unique designs in order to meet the project schedules.