Shear strength of pseudo strain hardening cementitious composite coupling beam

Abstract

Experimental and theoretical studies were conducted to propose an equation for predicting the shear strength of a pseudo strain hardening cementitious composite (PSH2C) coupling beam with steel fibers, polyethylene and embedded plates. The application of these fibers in structural member has been known to improve the post-cracking tensile strength of concrete, and significantly enhances the shear strength of RC beams. It is very important to quantify the post-cracking tensile strength of fibers and the contribution of embedded plate in the PSH2C coupling beams before discussing the proposed equation to predict the shear strength of the member. In particular, the post-cracking tensile strength rely on the shape of fibers, volume fraction, aspect ratio, bond stress between fibers and matrix, and the properties of the concrete matrix. For PSH2C coupling beams with a shear span-to-depth ratio (a/d) less than 2.5, the effect of shear transfer by arch action is also taken into account. The results of 71 tests of PSH2C beams were used to evaluate existing and proposed empirical equation for shear strength. The predicted values by proposed equation were in good agreement with both test results and other test data from the literature. Finally, this paper provides background for the simplified design equation to predict the shear strength of a PSH2C coupling beam with steel fibers and polyethylene.