A TOOL FOR NON-LINEAR DYNAMIC INVESTIGATION OF URM STRUCTURES

In this work, an effective modelling strategy for describing the non-linear behaviour of unreinforced masonry (URM) structures is presented. The approach uses the equivalent frame modelling and represents each masonry wall with macroelements, which are formed by zero-length multi-spring elements connected each other via elastic links. Each macroelement has two rotational springs, one at both ends and a shear spring in the middle of the length. Two specific hysteretic rules are used in the springs, describing the shear and the rotational hysteretic cycles. The employed laws account for stiffness and strength degradation, and the strength of each panel is calculated on the base of the axial load detected in the wall. Some numerical-experimental comparisons are presented to demonstrate the potential and the accuracy of the actual modelling.