Special edition paper

Past research has introduced some methods to improve shear reinforcement of reinforced concrete (RC) members. Those include cutting the adhesive force of the main RC rebar and embedding a plate or other artificial crack-inducing material so as to control crack development direction.1) 2) 3) But, we found it difficult to appropriately apply those methods to actual structures. We thus checked the shear capacity and failure form of RC beams having internal parts of higher tensile strength (“higher strength part”) with an aim of improving shear capacity of beams and the like having smaller shear-span ratios without dense arrangement of tie hoops. Specifically, we cast concrete to make samples where a higher strength part of aggregate and resin inside is placed in the mold used for making the RC beam samples (“samples”). Next, we carried out flexural loading tests to check the shear capacity and failure form of the samples. The test results revealed that samples with such higher strength parts inside show deformation behavior with two peak loads. This article will cover the details of the study