Modeling methodology for compressed earth block gravity masonry walls under seismic loading

The growing demand for low-carbon and locally sourced construction materials and the consequent interest in eco-construction solutions enhance compressed earth block (CEB) applications. The use of CEBs in retaining walls represents a potential solution for sustainable geotechnical engineering. The construction of CEB masonry gravity walls in seismic zones requires extending the research on earthen masonry in the framework of dynamic soil-structure interaction analysis. In this research, the performance of a CEB gravity retaining wall is first investigated under lateral earth pressure, in gravity conditions, and then under seismic loading. A three-dimensional (3D) finite element model is developed, through a simplified micro-modeling strategy, explicitly representing extended masonry units and both horizontal and vertical mortar joints. The contact law at the CEB interface is validated by comparison with single- and double-lap shear tests. The numerical simulation of the out-of-plane wall response under pushover loading, including tension and shear effects, and progressive joint degradation, is validated by comparison with published experimental data. The proposed 3D finite element model incorporates the simultaneous interaction between CEB masonry wall, backfill soil, and foundation soil. In seismic conditions, the CEB masonry wall model is coupled with a wave propagation model in a multilayered soil having nonlinear behavior. Inertial forces, soil response, and lateral residual displacement of the CEB masonry wall are directly simulated, as well as the possible interface cracking due to cyclic loading. The proposed modeling methodology represents a reliable numerical tool for assessing the feasibility and performance of CEB masonry gravity walls, supporting their integration into eco-construction and seismic design practice.