Parametric Study on Masonry Arches Using 2D Discrete-Element Modeling

Abstract

Maintenance of existing structures requires a solid understanding of their structural behavior and their varying geometry, boundary conditions, and load cases. For the case of the masonry arches, this understanding is still lacking in the field, yet masonry arches are crucial parts of the railway and highway network systems in many countries. In this study, two-dimensional numerical models were prepared to simulate the nonlinear response of masonry arches under static loading without soil–structure interaction effects. A custom-made discrete-element method (DEM) software was employed for this research, such that the models represent a discontinuous medium of rigid blocks. Different scenarios were generated on a hypothetical masonry arch model to observe the influence of different parameters on the structural behavior of masonry arches. Investigated parameters include effect of backfill and spandrel walls, bond pattern at the arch barrel for double-layer arches, and boundary conditions. In addition, the discrete-element approach and the software were validated by an experimental work from the literature. The results of the analyses show that discrete-element modeling is a powerful technique for demonstrating the development of collapse mechanisms of masonry arch structures. Parametric analyses also indicated that backfill and spandrel walls, if intact, can have beneficial effects on the load-carrying capacity of arches. Based on the results of this study, the bond pattern between arch layers does not make a significant difference in the overall behavior. As expected, boundary conditions matter, and they should be taken into careful consideration for each masonry arch bridge through detailed observations on site.