Verification of shear and torsional strength of prestressed concrete girders predicted using Australian Standards

ABSTRACT The design methodology for shear and torsional strength of reinforced and prestressed concrete beams have been changed recently following the release of AS5100-2017. The shear strength is now required to be computed based on the Modified Compression Field Theory. This is to align Australian practice with international practice. However, there have been many issues identified regarding this switch, especially for prestressed concrete girders. It is not clear to many engineers if the new methodology and formulations in AS5100-2017 do provide a better prediction of the shear strength. In this paper, the author set out to address this question by first explaining the basis of the formulation and the simplifications that have been made. To verify the model, a carefully selected database of published experimental data was collected and the test data was used to validate the accuracy of the code formulation. While the focus of this study is for shear strength of prestressed girders, shear and torsional strength for reinforced girders was also explored.