Experimental Testing to Determine Concrete Fracture Energy Using Simple Laboratory Test Setup

Insight into reinforced concrete structural behavior can be provided and experimental investigation can be complemented by nonlinear finite element analysis. Specification of material parameters, including post-peak tensile response curve shape, fracture energy, and concrete tensile strength is typically required in a concrete structure finite element model's development. A number of different tests for fracture energy and post-cracking response determination has resulted from previous research. A very stiff, closed-loop test machine typically needs to be used in these methods so load application can be performed under displacement control since extremely brittle response is exhibited by test specimens. A recommended fracture energy test method was employed in a recently computed University of Washington study, with an open-loop testing machine and test specimens modified to include counterweights. Test-generated post-cracking response data and fracture energy data fall within the typically observed recommended test range. Additionally, the laboratory-observed load-displacement response was reproduced, with acceptable accuracy through using these data for concrete constitutive model calibration for nonlinear finite element analyses.