Robotically controlled scale-model testing of masonry vault collapse

Calvo Barentin C., Van Mele T. and Block P.
Meccanica
2018
doi: 10.1007/s11012-017-0762-6

Scale-model testing can be used to understand the equilibrium and validate the computational modelling of discrete-element assemblies subjected to external loads or support displacement. This statement relies on the principle that the stability of these structures depends primarily on geometry, instead of material resistance properties. With the increasing sophistication of computational methods, the use of scale-model testing has been limited to specific problems. The reason for this decline is that scale-model testing is often more expensive and complex to implement than computational models. This paper proposes a novel approach to physically model the collapse of discrete-element assemblies, using force-sensitive robotic arms, combined with an optical measuring system, as testing setup for 3D-printed scale models. The proposed testing setup aims for a more flexible and comprehensive solution to assess the structural behaviour of unreinforced masonry structures. To demonstrate the possibilities of the presented setup, two different types of experiments are performed on the 3D-printed scale model of a cross vault. First, the robotic arms are used to apply a point load in different locations while measuring the resistance of the vault until collapse. In the second experiment, the robots are used to simulate the effect of progressive differential settlement of one of the supports. The trajectory along which the displacement of the support is applied is based on real-time measurements by the force-sensitive robots of the occurring outward thrust.