The physical disintegration of rock is a fundamental process by which the natural Earth as well as its man-made accessories is modified. Mechanical weathering is strongly linked to surface processes such as the erosion of mountain ranges and the production of sediment in streams. It is also responsible for the degradation of buildings and monuments. Nevertheless we have a poor understanding of how physical weathering is initiated in rocks that are not subjected to tectonic forces. Recent research suggests that daily thermal heating and cooling is important for the initiation of fractures in rock; however the physical mechanism by which cracking might occur though this process is unknown. The proposed research involves instrumenting rock surfaces with micro-thermometers, strain gauges and acoustic emission devices in an effort to determine the conditions under which cracking initiates. If temperature changes or gradients are responsible for cracking, there should be a correlation between rock surface temperatures, strain and the initiation of fractures as recorded by acoustic emission devices. The broader impact of the research lies in its potential to increase our understanding of the physical mechanism by which rocks, and thus man-made structures, deteriorate.
