Shear strength of prestressed concrete encased steel beams with bonded tendons

Abstract

This chapter focuses on the shear transfer mechanism of pre-stressed concrete encased steel (PCES) beam—a hybrid structural member that has not been thoroughly studied. Although a PCES beam is a hybrid beam comprising the features of pre-stressed concrete beams and structural steel beams, it is doubtful that either Diagonal Compression Field Theory or Diagonal Tension Field Action mechanism or both can be used to model the shear resistance of the hybrid beam. In this chapter, the results of shear tests on 6 PCES with bonded tendons are examined. The purpose of the test is to elucidate the shear performance of PCES with bonded tendons under monotonic loading. Evaluation and comparison of test results of PCES with the effect of various arrangements are made, such as number of stirrups, shear span depth ratio, and eccentricity of I beam. It is found that the contribution of concrete section to the overall shear resistance is significant, particularly at the onset of diagonal shear cracks. This chapter also demonstrates that the new pre-stressed concrete encased steel (PCES) beam system has a good potential for practical applications because it exhibits high stiffness and strength at service and ultimate states respectively, and considerable dependable ductility in the post-peak performance.