9th Turkish Conference on Earthquake Engineering, İstanbul, Turkey, 2 - 03 June 2021, vol.21, no.1, pp.173-180
Masonry is a composite material made of masonry blocks (brick, stone etc.) and mortar between the masonry blocks. Modeling is one of the most efficient ways of analyzing a structure in the closest way to the truth. Modeling of masonry structures is a significant necessary to strengthen historical masonry structures as well as to construct modern masonry structures. Throughout the engineering history, engineers, architects and researchers have worked to design durable and strong masonry walls. Numerical models can be used for designing masonry structures and verification of experiments on masonry structures. The finite element analysis (FEA) is extensively preferred numerical technique to model masonry structures. Confined masonry wall is one of the most encountered masonry wall types especially in earthquake prone regions. Confined masonry walls are generally preferred systems in building type structures. In this study, confined walls under in-plane cyclic loading are analyzed based on finite element method. Nonlinear structural behaviors of confined masonry walls are modeled and analyzed using 3D finite element models. Presentation of a nonlinear numerical model for a finite element software for masonry walls is one of the focus points of this study. Continuous micro modeling technique is used to model the masonry infill. The Drucker-Prager failure hypothesis a suitable hypothesis for materials which have high compressive strength but having low tensile strength, is used to specify the fracture mechanisms of the confined masonry walls. The modeling technique, the material model and the fracture hypothesis form a combination to model the confined masonry walls numerically. The hypothesis is used with elastoplastic material model to reflect the nonlinear behavior of the structure. The interaction between the masonry infill and frame is considered using contact and target finite elements. Masonry wall-frame system under both static and cyclic loading are analyzed. Confined masonry walls having different infill ratio are analyzed using the presented finite element model. The results obtained by the 3D finite element analysis on the confined masonry walls were found to be compatible with the experimental results in the literature. By using the finite element analyzes presented in this study, confined masonry walls can be successfully determined using the contact and target elements. It was seen that; confined masonry walls had generated dramatically more durable structure than masonry walls without confined frame systems. It can be stated that, the formed short column effect has significant effect on the strength and ductility of the confined masonry wall-frame system.