Influence of geometry on the collapse of masonry arches under horizontal loading

Abstract Kinematic limit analysis is widely used to identify collapse conditions in masonry arches. The collapse configuration can be defined by the hinge positions corresponding to the minimum collapse multiplier. The kinematic evolution of the mechanism may represent a complementary aspect of the problem. The proposed post-failure analysis describes the admissible kinematic evolution of the mechanism under the rigid-block assumption. The model provides a geometric continuation of the collapse mechanism, intended as a tool for interpreting the associated rotational demand rather than predicting the physical post-collapse response. Within this framework, the post-failure analysis provides additional insight into the kinematic behaviour of the mechanism, enabling the evaluation of the rotational demand and the identification of transitions between admissible collapse conditions. This approach extends the information obtained from limit analysis, by exploring the geometric evolution of the mechanism beyond the onset of collapse.