SOME NEW APPROACHES TO SUBSTRUCTURE DESIGN USING PRECAST CONCRETE COMPONENTS

Nearly 250,000 bridges in the United States are classified as structurally deficient or functionally obsolete. Only inventoried bridges with a span of twenty feet or more are included in this number, and little is known about the millions of smaller bridges. The intent of this paper is to familiarize the engineering community, contractors, fabricators, and bridge owners with the development of new precast concrete technology, to stimulate greater creativity in construction and maintaining of bridges. Design is explained in general terms; and three specific bridge systems using precast concrete substructures components are presented. They have been chosen for their simplicity and universality; design, construction and costs are discussed.