Keywords: dimension stone cladding, prestressed facade panels, structural performance, limestone panels, natural stone, hollow panels, compression force, bending tests, vibration tests, polyurethane foam filling, panel voids, failure modes, cracking, static load tests, FEA, finite element analysis, stress states
Structural performance of prestressed façade limestone panels
Experimental studies on the behaviour and performance of prestressed natural stone hollow panels were performed using prestressing wires as internal tendons to apply a compression force to pre–assembled dimension stone slabs forming the panels. Six prototypes were subjected to three–point bending and vibration tests, and the effect of filling the panel void with polyurethane and of the prestressing intensity was also studied. Dynamic tests were performed to obtain the panel's self natural period of vibration and the natural stone's Young's modulus. Static load tests were performed to ascertain the panels' suitability for application as stand–alone façade panels. The experimental results revealed two distinct failure modes after cracking, depending on whether polyurethane infill was injected into the void. The postrupture behaviour was analysed taking into account the favourable effect of filling the panel void with polyurethane foam. Finite element computer analyses of the stress states induced in the panels were also carried out for three different geometries. Data obtained from specimens subjected to the same load regime were compared.