Numerical analysis on the impact response of stone masonry arches with a GPGPU-parallelised FDEM

Stone masonry arches are composed of voussoirs, and they exhibit highly nonlinear and discontinuous characteristics under impact. A three-dimensional GPGPU-parallelised combined (hybrid) finite-discrete element method (FDEM) has been employed to investigate the impact failure of dry-jointed stone masonry arches in this study. The arch voussoirs are discretised into a number of constant strain tetrahedral elements, and each element is incorporated with finite element formulation, resulting in more accurate estimation on the deformation of voussoirs and the contact forces between them. Fracture of voussoirs is considered, and the transitioning from continua to discontinua is described using a cohesive zone model. Numerical results on the failure behaviour of a base case stone masonry arch are presented and validated with experimental records, and a good agreement is achieved. The influence of impact position, voussoir fracturing and angle of skew on the responses of stone masonry arches is addressed, and major conclusions are obtained as follows: (1) changing the in-plane impact position, the closer to the arch crown, the larger the structural response is; (2) changing the out-of-plane impact position, the global deformation of the arch is largely the same, except the impacted voussoir; (3) fracture of voussoirs results in increasing impact responses due to stiffness degradation; (4) a lower vertical impact resistance is expected for skewed stone masonry arches, and the impact resistance decreases correspondingly with the increase of the angle of skew. The FDEM has been demonstrated as an applicable and reliable tool in simulating the impact failure of stone masonry arches.