Headed Anchor/Engineered Cementitious Composites (ECC) Pullout Behavior

In this paper, the inelastic damage process in Engineered Cementitious Composites (ECC) in the high stress concentration zone adjacent to the head of an embedded anchor under tensile load was examined experimentally and numerically. An FEM model together with a tensile strain-hardening material model of ECC was developed to simulate the damage process leading to final failure. Experimental observations on the effect of tensile ductility on the microcracking damage process and anchor pullout performance were used to verify the numerical model. Furthermore, the influence of several material parameters, including tensile ductility, tensile strength, compressive strength and modulus of elasticity, on the anchor pullout behavior was clarified numerically. It was demonstrated that the intrinsic tensile ductility in ECC led to significant enhancement of load and displacement capacities. Once the failure mode was switched from brittle to ductile, however, the tensile strength governed the pullout load capacity. Finally, a design equation for predicting anchor pullout load capacity was proposed based on the numerical analysis and verified by experimental data.