A Discrete Element Method based-approach for arched masonry structures under blast loads

Abstract

Masonry structures are often characterized by complex, non-planar geometries. This is also the case for historical and monumental structures. Here we investigate the dynamic behaviour of non-standard, curvilinear masonry geometries, such as vaults, subjected to blast loading. We use the Discrete Element Method (DEM) for modelling the dynamic structural response to explosions. The approach allows considering the detailed mechanical and geometrical characteristics of masonry, as well as the inherent coupling between the in-and out-of-plane motion. The proposed modelling approach is validated with existing experimental tests in the case of planar masonry geometries, walls, subjected to far-field explosions. The DEM model is found to satisfactorily capture the dynamic response of the system and the form of failure within the body of the masonry structure. Then the response of an emblematic curved masonry structure subjected to blast loading is investigated. The influence of various micro-mechanical parameters, such as the dilatancy angle, the tensile strength and the cohesion of the masonry joints on the overall dynamic structural response of the system is explored. The effect of the size of the building blocks is also studied. Masonry joints with zero dilatancy lead to increased out-of-plane deformations and reduced membrane ones, with respect to associative case. Cohesion and tensile strength are found to have negligible influence on the structural response. The size of the building blocks shapes the overall strength of the system. Finally, the performance of a discrete model with infinitely rigid blocks is explored and evaluated through detailed comparisons of the parametric numerical tests using deformable blocks. The rigid blocks model predictions, for the loading conditions and geometries here investigated, are found to be affected by the rotational locking effect.

Rotation and sliding collapse mechanisms for in plane masonry pointed arches: statistical parametric assessment

“…For their simulations, these authors adopted for their models cohesion values of 0.010 and 0.007 for the normal and tangential cohesion thresholds parameters respectively. Masi et al [35] adopted cohesion values ranging from 0.0 to 3.0 MPa to perform a sensitivity analysis of arched masonry structures under blast loads using or damaged mortar.…”

Scaling laws for the rigid-body response of masonry structures under blast loads

“…For each surface, we account for the non-simultaneity of the load, the effects of surface rotation of the blocks, incident angle (Mach stem), and the relative distance between explosive and blocks, as for Method B. Following the approach in Vannucci et al (2017a); Masi et al (2020a) the position and the angle of incident of the front surface of blocks are used to computed the blast loads.…”

“…Gabrielsen et al (1975); Keys and Clubley (2017); Li et al (2017); Michaloudis and Gebbeken (2019); Masi et al (2019a). Research activity for the dynamic response of ancient and classical stone monuments in a blast event is, at the moment, modest and insufficient to draw appropriate preservation strategies and in-situ protections Masi et al (2019aMasi et al ( , 2020a. This is due to the fact that blast testing of masonry structures is particularly challenging due to its mechanical properties.…”

Static and Impact Response of a Single-Span Stone Masonry Arch

“…Despite the work carried out on the impact and blast response of masonry walls with a flat geometry, the behavior of curvilinear geometries under these types of loadings has not been widely studied, as indicated by Masi et al [16]. Their study is a rare example of research investigating the blast behavior of curved masonry structures, particularly vaults, using the discrete element method (DEM).…”