The Development of a Test Rig for Inplane Dynamic Testing of Masonry Panels in a Uniaxial Testing

The purpose of this research program is to investigate the dynamic failure properties of an unreinforced masonry panel under controlled dynamic loading conditions. This rig design is based on the classic diamond loading pattern. It is designed to achieve a uniform stress over the central area of the panel. The aim of the measurements will be to measure the rate of damage evolution in an inital “square” of masonry in the centre of the overall panel. A test rig has been designed that is capable of applying a nonproportional quasi-static biaxial loading coupled with a dynamic shear force to a 1.2 metre square masonry panel. The uniaxial cyclic loading to develop the sinusoidal shear-loading pattern will be supplied by an Instron 250 kN UTM. Masonry, when constructed from brick units and mortar, exhibits a wide scatter of experimental results even for an apparently consistant product. One’s interest from the experimenter’s viewpoint is thus focussed threefold to better understand the constitutive relationships of the material; firstly on the intrinsic material properties such as Young's Modulus, secondly by understanding the material’s basic properties and providing a high quality control on the masonry so as to limit the number of tests undertaken experimentally because of the time and reducing the experimental scatter for a given unit and thirdly to provide a valid numerical model for the experimental results. This paper's objective is to outline in detail the design and construction aspects of interest for the development of the mechanical items for this test rig. The loading pattern and electronics will be dealt with in future papers.