Located on the edge of Saint Paul, MN, the Rice Street / I-694 interchange was prone to bottleneck congestion, even outside of rush-hour traffic. MnDOT estimated that over 19,500 vehicles traveled the interchange each day, and that number was bound to increase as the area continues to grow. To alleviate traffic congestion, MnDOT initiated an expansive redevelopment project that would change how traffic flows on I-694. During the preliminary stages, 14 designs were drafted and evaluated for their impact on improved traffic operation, design feasibility, and construction and maintenance costs. The final design outlined the reconstruction of the existing Rice Street bridge in addition to building two bridges for entrance and exit ramps. Prestressed girders were chosen for their ability to improve operations, lower costs, and achieve a prolonged service life with minimal maintenance.
Because the interchange operated as a major corridor for the region, long periods of closure were not an option. County Materials delivered twenty MN45 prestressed girders within 24 hours during the first phase of the project to maintain the tight construction schedule. The girders ranged in length from 97 to 127 feet long. Of the girders delivered, eight went into constructing the new exit ramp and the other twelve went into reconstructing the east side of the overpass.
Through incredible preparation and coordination, all girders arrived on-time and the interchange was able to remain open at reduced capacity during construction.