Finite Element Detailed Micromodeling of Unreinforced Earth Block Masonry

The structural response of earth block masonry is characterized by cracking patterns and inelastic behavior distributed across masonry units, mortar joints, and unit-mortar interfaces. This behavior is different from that exhibited by masonry built with fired clay bricks, concrete blocks, or regularly shaped stones, which are commonly characterized by cracking patterns and inelastic behavior within the mortar joints and unit-mortar interfaces and are typically analyzed using finite element (FE) simplified micro-models (SMMs). This paper presents a new detailed micromodel (DMM) specifically tailored for earth block masonry systems. The proposed DMM enables the accurate simulation of the experimentally-measured mechanical response of earth block wallettes subject to combined shear-compression diagonal loads, whereas the SMMs produce inaccurate results. Through a series of FE simulations of representative masonry elements, this study shows that the proposed DMM and different types of SMMs provide consistent predictions of mechanical behavior only under specific conditions, depending on the relative strength of masonry units and mortar as well as the loading conditions. The outcomes of this research provide a new tool for accurate prediction and simulation in instances where the compressive strength of the masonry units is similar to or lower than that of the mortar.