Collapse analysis of unreinforced masonry vaults using 3D-printed scale-model testing

Rossi M., Calvo Barentin C., Van Mele T. and Block P.
Proceedings of the 7th International Conference on progresses made in Experimental Structural Engineering (7AESE)
EUCENTRE Poundation
Pavia, Italy
2017

The use of scale-model testing for analysing the behaviour of masonry structures is justified by Heyman’s assumptions that establish the main cause of masonry collapse is geometry and not the strength of material. Recently, several works have proved the capability of scale-model tests of simulating complex three dimensional mechanisms of vaulted structures, but more investigations have still to be done. This paper focuses on the analysis of collapse mechanisms of small scale models of a pavilion vault and a cross vault made by 3D-printed discrete blocks with dry joints. The main aim is to show the potential of using scale models made of 3D printed discrete units, in combination with innovative testing setups to analyse collapse mechanisms of vaulted structures subjected to both forces and displacements. In both the cases, an optical measuring system, the PONTOS dynamic 3D motion, allowed for capturing the development of the 3D collapse mechanisms and calculating the displacements of each block by means of a software of analysis, which can track dotted targets located on the extrados block’s surfaces. The pavilion vault was tested applying controlled symmetric and asymmetric outwards displacements at its supports with an actuated testing table. The tests on the cross vault’s model were performed using an innovative testing setup using force-sensitive robotic arms that allowed applying both controlled forces and displacements. The robots are able to apply in a flexible way and both applied forces and reaction forces can be measured in real time.