FUNDAMENTAL STUDY OF SIMPLE IRREGULAR POLYHEDRAL 3D-DEM MODELUSING HEXAHEDRON COMBINATION AND ITS VALIDATION BASED ON BRICK DROP EXPERIMENTS

Abstract

 Masonry retaining walls are very fragile structures against earthquakes and a great number of damage cases have been reported. In order to mitigate such damage, it is necessary to understand the collapse mechanism of masonry walls during an earthquake and to evaluate stabilities and countermeasures. In recent years, several studies of the collapse mechanism have been conducted by numerical analyses. However, most of them used a simple shape model for representing masonry blocks. In order to develop three-dimensional DEM elements applicable to various arbitrary polyhedron shapes, the objective of this study is to investigate the fundamentals of the simple irregular polyhedral models that can represent the arbitrary shape by combining a number of hexahedral blocks. Then, we conducted drop experiments using wooden blocks with a convex shape and sliding tests for obtaining the friction coefficient. In order to validate the developed irregular polyhedral elements, we carried out the three-dimensional numerical simulations of the drop experiments. As a result, the block behaviors of experiments and numerical analyses show good agreement with each other.