When roadways are constructed above or adjacent to heavily mined regions, the ground subsidence caused by pillar collapse inflicts severe damage on these roadways. In this study, some surface subsidence events were first reviewed to present roof caving characteristics caused by pillar failure. The bearing characteristic and failure pattern of a single pillar with or without effect of discontinuity were further numerically simulated using distinct element code (3DEC). It was found that the spalling of pillar or slippage of discontinuity would damage the bearing capacity of pillar during the failure process. The stress at the pillar core could be greater than uniaxial compressive strength of the pillar. However, when a discontinuity runs through a pillar, the slippage of discontinuity would significantly degrade the bearing capacity of the pillar. In pillar support system, if any pillar unexpectedly degrades or loses its bearing capacity, the load transferred from the degraded pillar acts on neighboring pillars, and the shear force also increases at relevant positions. However, the roof cutting and surface subsidence characteristics would perform in different patterns. In some cases, surface subsides slowly; in the worst scenario, shock bump may be induced by pillar and roof collapse.

当在高雷区之上或附近建造道路时，由柱倒塌引起的地面沉降会对这些道路造成严重破坏。在这项研究中，首先对一些地面沉降事件进行了综述，以显示由柱破坏引起的顶板崩落特征。使用不同的元素代码（3DEC）进一步数值模拟了具有或不具有不连续性影响的单个支柱的承载特性和破坏模式。发现在破坏过程中，柱的散裂或不连续的滑动会破坏柱的承载能力。柱芯处的应力可能大于柱的单轴抗压强度。但是，当不连续点穿过支柱时，不连续点的滑动会大大降低支柱的承载能力。在支柱支撑系统中，如果任何支柱出乎意料地劣化或失去其承载能力，则从劣化的支柱传递来的载荷将作用在相邻的支柱上，并且在相关位置处的剪切力也会增加。但是，屋顶切割和地面沉降特征将以不同的模式表现。在某些情况下，表面会缓慢沉降。在最坏的情况下，支柱和屋顶倒塌可能会引起震动。