Chapter 14 - Descrete macroelement modeling

Abstract

The numerical prediction of masonry monumental structures is a complex issue, due to the difficulties in adequately simulating the nonlinear cyclic response of masonry material. In principle, nonlinear finite element modeling (FEM) can be rigorously applied for large monumental structures. However, these approaches still require high computational resources and specific expertise that limit their application to few academic studies or significant cases. For these reasons, several researches are currently involved in the formulation and validation of alternative numerical strategies to be efficiently applied for the structural assessment of masonry monumental structures. Among the simplified approaches, a widely used strategy is the so-called equivalent frame model (EFM), which has received several numerical and experimental validations. In this study, after a description of the recent evolutions of the EFM, an original discrete macroelement method, developed by the authors in the last decade, is presented. The method is based on a discrete macroelement discretization in which the interaction between the shear deformable elements is governed by zero-thickness interfaces that also rule the mechanical behavior of the corresponding adjacent elements according to a straightforward fiber discretization strategy. The approach requires a very low computational burden, compared to classical nonlinear FEM simulations, and allows efficient modeling of large masonry structures such as churches, monumental buildings, or masonry arch bridges. Several comparisons with numerical and experimental results show the ability of the proposed discrete macroelement method to efficiently simulate the nonlinear behavior of historical masonry structures.