The Georgia Department of Transportation and the Georgia Institute of Technology, through research and application, have confirmed the benefits and cost savings of high-performance concrete in increasing the span length and in reducing the size of precast, prestressed concrete girders. Their work has demonstrated the following benefits: the production of 10,000-psi and 7,000-psi concrete with locally available materials; a span increase of approximately 40% for the same cross section of girder; a reduction in the depth of the superstructure, eliminating such potential problems and costs as raising the grade or purchasing additional land; reducing the number of prestressing strands and increasing span length and girder spacing with 0.6-in.-diameter strand instead of 0.5-in. strand for precast, prestressed girders; enhanced durability and reduced cracking, leading to lower maintenance cost and longer service life; and potential cost savings in comparison with conventional concrete, estimated at 10% for a recently constructed bridge in Georgia.
Samenvatting