Impact of High Strength Concrete on the Design and Construction of Pretensioned Girder Bridges

摘要

align="left">The use of high strength concrete in the fabrication and construction of pretensioned concrete girder bridges can result in lighter bridge designs, with corresponding economic advantages, by allowing? longer span lengths and increased girder spacings for standard shapes. A parametric study was performed comparing the required girder spacings and/or the allowable span limits for four commonly used? cross-sectional shapes: the Texas Type C, the AASHTO Type IV, the AASHTO Type IV Modified, and the newly developed Texas Type U548. The results clearly show that the use of high strength?? concrete can lengthen the allowable bridge span for concrete girders made from standard cross-sectional shapes or can decrease the number of girders required for a given design case. Furthermore, the? results demonstrate that the flexural efficiencies of the different cross sections are similar if the depth of the cross sections is the same. Perhaps most significantly, this investigation illustrates that, through? the use of high strength concrete, longer spans can be achieved using shallower cross sections in place of deeper cross sections.