Simplified micro-model for brick masonry walls under out-of-plane quasi-static and blast loadings

Abstract

Attributed to the discontinuous configurations and nonhomogeneous mechanical properties of brick and mortar in masonry wall, the numerical reproduction of the structural responses and damage evolution of masonry walls under out-of-plane (OOP) loadings still remains a challenging work. Firstly, a 3D simplified micro-model of masonry wall was developed by utilizing the commercial finite element program ANSYS/LS-DYNA, the masonry wall was simplified as a combination of expanded brick units with a series of joints, in which the expanded brick units and joints are described by Riedel-Hiermaier-Thoma (RHT) model and cohesive contacts, respectively. Then, the corresponding parameters determination approaches for the cohesive contact and RHT model are proposed by comparing with the test on brick-mortar-brick assemblages and regulation, respectively. Furthermore, by comparing with four sets of OOP quasi-static and field explosive tests data, the prediction accuracy and efficiency of the simplified modeling strategy, material model and parameters are fully validated. Finally, based on the parametric study, it indicates that the blast resistance of walls is enhanced with increasing the compressive strength of brick and mortar, and arranging the tie bars, while significantly degraded with increasing the aspect and slenderness ratios of walls. This work could provide a helpful reference for the blast-resistant evaluation and design of brick masonry walls.