Scaling Laws for Rigid-Body Response of Masonry Structures under Blast Loads

Abstract

The response of masonry structures to explosions cannot be exclusively investigated relying only on numerical and analytical tools. Experimental tests are of paramount importance for improving current understanding and validating existing models. However, experiments involving blast scenarios are, at present, partial and limited in number compared to tests under different dynamic conditions, such as earthquakes. The reason for lies in the fact that full-scale blast experiments present many difficulties, mainly due to the nature of loading action. In constrast, experiments on a reduced scale offer greater flexibility. Nevertheless, appropriate scaling laws for the response of masonry structures under blast excitations are needed before such tests are performed. We propose here new scaling laws for the dynamic, rigid-body response, and structural failure modes (e.g., overturning) of masonry structures under blast loads. This work grows out of previous studies, where closed-form solutions for the rocking response of slender blocks due to explosions were derived and validated against numerical and experimental tests. The proposed scaling laws are validated here with detailed numerical simulations accounting for combined rocking, uplifting, and sliding mechanisms of monolithic structures. Then the application to blocky masonry structures is studied. Multidrum stone columns are considered as examples for the application of scaling laws. In particular, we show that, despite the presence of complex behaviors, such as wobbling and impacts, similarity is assured.