The mechanics of deep‐seated landslides
The mechanics of deep‐seated landslides
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DOI：
10.1002/(sici)1096-9837(199708)22:8
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发表时间：
1997-08
影响因子：
3.3
通讯作者：
D. Petley;R. Allison
中科院分区：
文献类型：
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作者：
D. Petley;R. Allison
介绍了一系列实验室测试的结果，以阐明深部滑坡的行为。在深层破坏中，据报道在250米深处发生了变形。在移动区，由于覆盖层的重量和周围的应力环境，传统的土力学不能有效地解释滑坡活动与移动体内的变形机制之间的关系。在伦敦粘土上进行了一系列实验，使用高压、伺服液压控制的三轴变形系统，以复制作用于大型深部滑坡底部的应力。进行了许多测试，其中最重要的是延性和脆性之间的转变。虽然沉积物在低有效应力下通常表现为脆性(许多地貌学研究常见)，而在高有效应力下通常表现为延性，但本文的结果首次在泥岩中发现了一个行为的过渡阶段，在这个阶段，蠕变运动将在深层滑坡的底部表现为微裂缝的生长。微裂纹最终可能结合形成剪切面，其结果很可能是突然破坏。因此，这些结果对理解大型深层次断层的运动机制、位移速率及其随时间的变化具有重要意义。©1997 John Wiley&Sons，Ltd.
Results are presented of a sequence of laboratory tests undertaken to elucidate the behaviour of deep-seated landslides. In deep-seated failures deformation has been reported at depths of up to 250 m. In the movement zone, owing to the weight of the overburden and the surrounding stress environment, conventional soil mechanics cannot be used to explain effectively associations between the landslip activity and the deformation mechanisms operating within the moving mass. A series of experiments has been undertaken on London Clay using a high pressure, servohydraulically controlled triaxial deformation system, to replicate the stresses acting at the base of a large, deep-seated landslide. A number of tests were undertaken, the most significant focusing on the transition between ductile and brittle behaviour. Although sediments usually behave in a brittle manner at low effective stresses (common to many geomorphological studies) and in a ductile manner at high effective stresses, the results presented here identify for the first time in mudrocks a transitional phase of behaviour in which creep-like movement will manifest itself at the base of a deep-seated landslide as the growth of microcracks. The microcracks may eventually coalesce to form a shear surface, a consequence of which is likely to be sudden failure. The results thus have important implications in the understanding of movement mechanisms in large, deep-seated failures, rates of displacement and how they may change through time. © 1997 by John Wiley & Sons, Ltd.