Shear capacity of continuous pre-stressed concrete bridge girders with different static systems through vertical prestressing

Abstract

Some existing bridge girders do not satisfy current shear strength requirement and so study of this strength seems essential. Shear strength of pre-stressed concrete bridge girders with and without vertical prestressing is studied in this paper. First several models of prestressed concrete beams are selected and analyzed using the finite-element method. In this regard the validity of modeling is evaluated based on some test performed on an existing bridge girder in Switzerland. In the second part of the study several beam specimens are built and tested and their load-deformation curve and cracking pattern are studied. Using all numerical and experimental studies, the slope of shear cracks and shear reinforcement ratio are investigated and the effect of horizontal and vertical pre-stressing on the noted parameters is evaluated. The findings should be of interest to researchers as well as practicing engineers involved in analysis and design of prestressed concrete beams.