An extensive laboratory testing program was conducted to investigate the shear strength of prestressed concrete girders. A comparison between the various models for predicting shear strength and the results of tests on twenty full-scale AASHTO Type II prestressed concrete girders are presented. Three of the test girders contained no shear reinforcement and were tested to determine the concrete contribution, V, to shear strength. The main variables of this study were the amounts of shear reinforcement and the shear span. The test shear strengths are compared with predictions based on the 1989 AASHTO Standard Specifications for Highway Bridges and the 1994 AASHTO LRFD Specifications. The results show that the application of the 1989 AASHTO Specifications gives a much better prediction of shear strength than the LRFD provisions, indicating that the latter require some examination and modification to increase reliability
