Interactive Finite Element Analysis of Reinforced Concrete: A Fracture Mechanics Approach

摘要

Problems associated with interelement crack nucleation and propagation were analyzed. An interactive computer code was used to examine the stress singularity at the tip of the crack and to study fracture mechanics criteria for the stability and the length of the crack extension. A computer program was developed which is capable of automatically simulating discrete crack nucleation and extension through a finite element mesh as governed by an appropriate analysis. A parametric study of a reinforced concrete beam was performed and the effects of fracture toughness, aggregate interlock, and concrete non-linearity were assessed. The simple linear model gave a satisfactory correlation with experimental results for up to half the failure load. An improvement in the correlation, up to the failure, was achieved by modeling the concrete as a non-linear material. It was also found that while a large variation in the concrete fracture toughness resulted in a slightly stiffer response, the aggregate interlock played a crucial role. A tunnel opening in rock was analyzed and results were found to be in good agreement with the available experimental evidence.