South Main St. over Tanyard Branch Bridge Replacement | De Soto, Missouri
Juneau Associates Inc., P.C. was contracted by the City of De Soto, Missouri, to replace an existing single span bridge, 28 feet long by 40 feet wide. Juneau’s tasks included topographic, property, hydraulic surveying, evaluating various bridge replacement options and preparing both preliminary plans, right-of-way plans, and final construction documents. Construction phase services included construction inspection, shop drawing reviews and answering contractor’s RFIs.
The South Main Street Bridge was 80% federally funded and administered through East-West Gateway. Plan review was provided by MoDOT.
The proposed option chosen for this project was a single span structure, 43 feet long and 38 feet wide. The bridge accommodates two 12 foot wide traffic lanes, two (2) three foot wide shoulders, one (1) five foot wide sidewalk with an aesthetic pedestrian fence and two 13 inch wide Kansas Corral rail barriers. The roadway alignment was improved to provide for a 25 MPH design and the bridge structure is located on a tangent section of this alignment. The bridge superstructure consists of five 11X52 Prestressed Concrete Spread Box Beams supporting an eight and one-half inch thick reinforced concrete deck. The substructure consists of vertical wall abutments supported by spread footings.
The hydraulic opening of the bridge structure was designed such that it produces less than one foot of backwater over the natural or no bridge condition for the 50-year design storm and the 100-year base flood event. It was also designed to provide a larger hydraulic opening when compared to the existing structure and to provide no rise certification.
