The DSC Model for the Nonlinear Analysis of In-plane Loaded Masonry Structures

Abstract

A nonlinear finite element method with eight-noded isoparametric quadrilateral elements is used to predict the behavior of unreinforced masonry structures. The disturbed state concept (DSC) with modified hierarchical single yield surface (HISS) plasticity which is called DSC/HISS-CT is used to characterize the constitutive behavior of masonry in both compression and tension. The model uses two HISS yield surfaces for compressive and tensile behavior. The DSC model allows for the characterization of non-associative behavior through the use of disturbance. It computes microcrack-ing during deformation, which eventually leads to fracture and failure. the critical disturbance, Dc, identifies fracture and failure. In the DSC model the DSC model was validated at two levels: (1) specimen and (2) practical boundary value problem. At the specimen level, predictions are obtained by integrating the incremental constitutive relations. The pro-posed constitutive model is verified by comparing numerical predictions with results obtained from test data; the compari-sons are found to be highly satisfactory. A new explicit formula is also presented to estimate the strength of unreinforced masonry structures.