Experimental and analytical investigation on the evaluation of residual stresses in prestressed concrete girders

Abstract

Since the strength of prestressed reinforced concrete (PRC) structures, particularly under shear, substantially depends on the effective residual prestressing force, the evaluation of residual stresses in prestressed concrete structures is currently a target of importance. Three semi-destructive techniques were used on the 4 PRC full scale: core trepanning, saw-cut at intrados, and blunt pyramidal specimen for in-situ prestressing evaluation based on tension release. Furthermore, a novel method, resembling parallel saw cuts at the intrados but applied to the web, was introduced and examined. Among the tested techniques, this latter approach demonstrated the highest reliability, and both 2D and 3D finite element models were developed and extensively discussed to support the findings.