Parameters Affecting FE Analysis of Concrete Structures

Abstract

The effects of the shape of the descending branch of the tensile stress‐strain curve, fracture energy, grid refinement, and load‐step size on the response of finite element models of a notched concrete beam are studied. The width of the process zone and constraints imposed on crack angles are also investigated. Cracking of the concrete in tension is the only nonlinear behavior modeled. Load‐deflection curves and general cracking patterns provide the primary means for evaluating response. Comparisons with discrete crack models are made. The fracture energy, tensile strength, and shape of the descending branch interact to determine the stiffness and general behavior of the specimen. The width of the process zone has a negligible influence on the beam's response. The importance of proper crack orientation is demonstrated. The model is objective with respect to grid refinement and load‐step size. The implications of the results are discussed with respect to modeling reinforced concrete structures.