Dynamic response of reinforced masonry columns in classical monuments

From the mechanical point of view, the particularity of masonry structures stems from the fact that the structural system is hard to be modeled by the classical Continuum Mechanics approach. The problem gets more complicated when imperfections, such as cracks are present. An example of a single multi-drum column, with fractured drums, is studied herein, using the Distinct Element Method (DEM). The purpose of the research is the investigation of the impact of the fractures to the overall stability of the structure. The 3D DEM numerical results are explained on the basis of simple 2D analytical considerations. The shear and normal crack deformation is monitored and the minimum required strength of the crack interface is quantified. An experimental program of direct shear tests is set in order to estimate the strength of the marble–cement interface. The experimental values are compared to the minimum required from the numerical analysis.

Research highlights
► 3D analyses are necessary for studying multi-drum masonry columns.
► Imperfections may cause loss of stability under static or dynamic loading.
► The crack-plane characteristics control the overall stability of the structure.
► 3D DEM allows determining the stresses developed at the crack-plane.
► Cement paste offers beneficial cohesion and tensile resistance.