SGER: Preliminary Instrumentation Study of Rates and Mechanisms of Crack Initiation and Mechanical Weathering

岩石的物理分解是自然地球及其人造附属物发生变化的一个基本过程。机械风化与山脉侵蚀和溪流沉积物生成等地表过程密切相关。它也是建筑物和纪念碑退化的原因。然而，我们对不受构造力影响的岩石如何开始物理风化的了解很少。 最近的研究表明，日常的热加热和冷却是重要的岩石裂缝的开始，但开裂可能发生的物理机制，虽然这个过程是未知的。 拟议中的研究涉及用微型温度计、应变计和声发射装置对岩石表面进行仪器测量，以确定裂纹发生的条件。 如果温度变化或梯度是造成裂缝的原因，那么岩石表面温度、应变和裂缝的开始之间应该存在相关性，如声发射设备所记录的。这项研究的更广泛影响在于它有可能增加我们对岩石以及人造结构恶化的物理机制的理解。

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.