Web-Shear Capacity of Thick Precast Prestressed Hollow-Core Slab Units Produced by Extrusion Method

Abstract

The prestressed hollow-core slab (PHCS) is a precast concrete member that can maximize productivity and structural performance efficiency of concrete cross-section. For the PHCS members produced by extrusion method, however, it is difficult to provide the shear reinforcement due to its unique production method to form the hollow-cores in concrete section. The recently revised ACI318 Building Code Requirements stipulate that web-shear capacity of thick hollow-core member over 315mm depth without the minimum shear reinforcement should be reduced in half, which may result in an excessively conservative shear design for the PHCS member compared to conventional prestressed concrete members with thin webs. In this study, shear tests on PHCS members, which have typical thicknesses widely used in precast construction industry, were conducted, and a large number of shear test data were additionally collected from previous studies to evaluate the current shear design criteria for PHCS in detail.