Rules of the Art and the Non-standard Behaviour of Masonry

The paper presents a series of tests made on simple block structures with a DIY shaking table. Details are first given about the rig and the experimental setup. Besides providing information useful to understand the purpose and condition of the experiments, the aim of this first section is to discuss changes introduced in hardware and software (since its first presentation) and to describe how footages taken during the experiments were processed using OpenCV. The section may be of interest to anyone interested in low-cost shaking tables. The second section presents two series of tests: a first one, static, during which the abutments of the block structures are subjected to differential displacements, and a second one, dynamic, during which the same block structures are subjected to short Morlet-type wavelets impulses. The structures were designed to be as elementary as possible to clarify the effects of limited friction, wedging, and bounds on the normal forces. These factors are important for masonry structures as they are related to their non-standard behaviour. The first series of static tests is compatible with previous analytical research, showing how bounds on the normal forces acting on joints can be used to build safe domains. The second series of dynamic tests led to a very different outcome. Both confirm the difficulty of mathematical modelling and the importance of the rules of Art used in masonry constructions. They contribute to safety and often justify the trust that analysts can have in simplifying assumptions (when they are followed).