Dynamic failure of dry-joint masonry arch structures modelled with the combined finite-discrete element method

As assemblage of blocks, masonry arch structures are highly discontinuous. The combined finite-discrete element method (FDEM) where finite elements are incorporated into discrete elements is employed to investigate the dynamic failure behaviour of dry-joint masonry arch structures subjected to base motions in this paper. By using this method, both the internal deformation of blocks and the contact action between blocks could be simulated accurately. With a cohesive fracture model implemented, rupture of blocks is also considered. Oppenheim's arch and buttresses-supported arch structures are examined. Numerical results are compared with those from analytical and other computational sources. Failure thresholds for both monolithic and multi-block buttresses-arch masonry structures are provided. Typical failure modes due to hinge instability and ring separation are identified. Relationships between triggering factors and failure modes are revealed for future research. In general, the FDEM is proven to be successful in simulating the dynamic failure of dry-joint masonry arch structures.