采动影响下覆岩破坏动态发展过程的数值模拟

Numerical Simulation of Overburden Rock Strata Fracture Dynamic Progressive Process Induced by Caving

利用岩层破裂过程分析(RFPA2D)系统,模拟了采动影响下覆岩破坏的动态发展过程,从几何、岩性、变形、破断机理及支撑特征等多方面较真实地模拟开采过程中上覆岩层变形、离层、断裂规律。模拟结果表明,开挖卸荷作用对老顶的直接影响比较小,老顶的破坏主要受随分步开挖而增大的拉应力及其损伤的积累作用,老顶初次破断机理是拉破坏失稳。老顶岩梁中段下部的拉应力损伤积累峰值位置滞后于岩梁最大拉应力区,这是造成老顶非对称破断的根本原因。

Dynamic progressive process of overburden rock strata fracture induced by caving is simulated by rock Rock Fracture Process Analysis system（ RFPA^2D） code. Moreover, it is simulated by the same code that controlling mining pressure and falling of rock layer above the ore bed by the reserved coal pillars. The simulated results reveal that RFPA^2D can realistically simulate deformation, vertical discontinuous displacement, fracture and surface subsidence law of overburden rock strata from geometrical characteristic, rock mechanical property, deformation, fracture mechanism and support character- istic. Therefore,it can conclude that RFPAED is a new approach to research overburden rock strata fracture.