SHEAR BEHAVIOR OF JOINTS IN PRECAST CONCRETE SEGMENTAL BRIDGES

Joints between segments in precast concrete segmental bridges (PCSB) require special attention in design and construction. These joints introduce discontinuity in the bridge; meanwhile they must transmit compressive and shear stresses. Tests were carried out to assess the shear strength and deformation behavior of precast segmental bridge joints. The parameters studied included flat and keyed joints, without epoxy (dry) and with, the level of prestressing, and the epoxy thickness. It was found that the strength of epoxied joints is consistently higher than that of dry joints. However, the failure of the epoxied joints was found to be very sudden and brittle. Formulas are proposed for assessing the shear strength of PCSB joints. Combinations of these formulas with the current ACI and AASHTO specifications for shear design, aimed at preventing diagonal failures, may provide a rational basis for the design of PCSB. © ASCE.