A Precast Segmental Substructure System for Standard Bridges

A precast segmenta! substructure system for standardization is presented. This system is intended to support precast concrete girder superstructures in non-seismic regions and provides an alternative to current cast-in-piace systems, particularly for areas where reduced construction time is desired. The substructure system is made up of predominantly precast elements. Four different column sizes with one basic cap shape are proposed to he assembled as single column, straddle and frame bents for varying heights and widths of standard bridges. Precasting allows for increased use of high performance concrete in the substructures, thus improving durability. In addition, the greater compressive strength of the high performance concrete is utilized to reduce the handling weight and dead load of the substructure units, facilitating construction. The construction method proposed will significantly shorten on-site construction time. Shortened construction time, in turn, leads to important safety and economic advantages when traffic disruption or rerouting is necessary.