Thin granite structural veneer cladding panels are popular in the building industry due to their aesthetic value and low maintenance requirements. Although generally used as a cladding, and seldom as a structural element, its thinness has given rise to concern over its flexural resistance against wind loading. Besides, as it is usually installed on the exterior of buildings, they inevitably suffer from weathering by physical, chemical or biological means. It is therefore important to understand the design strengths of these granite claddings panels and the effect of weathering on these strengths, so that the chance of failure, with potentially catastrophic results, can be minimised.
This thesis is a continuation of previous thesis research and is primarily focused on the weathering of granite by wetting-drying cycles and acids. It includes a brief review of recent research on the weathering of granite.
Experiments were performed to determine the effect of wetting-drying cycles and moderately-acidic solution on the strength of thin granite structural veneer cladding panels. No significant short-term effects by wetting-drying cycles and acid on these panels were observed.
An evaluation was also conducted into the possibility of using ultrasonic pulse velocity (UPV) as a non-destructive test in the determination of the modulus of elasticity of the granite panels.
Although it was found that UPV cannot give accurate measurement of the modulus of elasticity of granite, it is shown that it can still serve as a convenient method for detecting any imperfections in the interior of a granite panel. It is proposed that destructive testing could first be carried out on a few samples to obtain the necessary material properties, such as the Poisson’s ratio and modulus of elasticity, for the calibration of the UPV apparatus. The apparatus can then used to measure any discrepancies which may indicate any discontinuities or boundaries inside the granite. The anisotropic characteristics of granite demand that comprehensive testing must be conducted in order to determine how this directional effect influences the material properties of a particular type of granite.