EXPERIMENTAL INVESTIGATION AND FINITE ELEMENT MODELING OF INTERFACE BOND-SLIP BEHAVIOR BETWEEN SHAPE STEEL AND ECC

In order to study the interface bond-slip behavior between shape steel and Engineered Cementitious Composites (ECC), the shape steel-ECC specimens were designed to conduct push-out testing. The influences of the volume fraction of PVA fiber, stirrup reinforcement ratio, ECC cover thickness and shape steel embedment length on the failure modes, on the load-slip curves and on the bond stress of shape steel-ECC specimens were analyzed, also the bond stress distribution along steel embedded length was proposed. The result shows that the volume fraction of PVA fiber and ECC cover thickness have great influences on bond stress. The maximum bond stress occurred near the loading end, and the equivalent bond stress increased with the increase of the load. According to the test results, the expression of bond stress in different states were established, and the bond-slip constitutive laws were proposed. On this basis, the finite element model of shape steel-ECC specimens was established by using a nonlinear spring to simulate the interface bond-slip behavior between shape steel and ECC. The finite element analysis results were compared with the test results, which indicated that the finite element simulation method proposed could accurately analyze the interface bond-slip behavior of shape steel-ECC.