Modeling masonry walls under far-field and contact detonations

Masonry walls represent one of the most common applied constructions in civil engineering and architecture. The inhomogeneous nature of masonry imposes a challenge in the development of robust modeling techniques especially under high dynamic loads. In this contribution some modeling strategies are discussed which are suitable for the simulation of unreinforced masonry walls under explosion loads. The damage formation of the wall under loads resulting from far-field as well as contact explosions is investigated. Firstly the issue of an appropriate material model for bricks under high strain rates is discussed. Through a proper adaptation of a material model initially developed for concrete under blast loads all the necessary parameters for the bricks are derived. Subsequently the focus lies in capturing the local damage formation and the resulting debris due to a contact detonation. Small parts of the wall in the proximity of the explosion separate from the main body of the wall and travel at high velocities. They can establish an additional danger for persons and infrastructure which theoretically lie in a secure distance from the target of the explosion. The numerical results which will be presented in this paper are validated with appropriate experiments.