地下开采过程损伤场演化与地表变形的时变分析

Time|varying analysis of damage field evolution and surface subsidence in underground mining process

以形状随时间变化的物体——时变体为研究对象,将损伤理论与时变力学结合,引入与时变过程相关的损伤参数,形成损伤时变力学分析方法。针对岩石介质特性给出了弹性损伤时变力学本构方程,并利用虚功原理建立相应数值化方法和分析过程。利用损伤时变力学分析方法对某地下煤层开采过程进行计算机仿真分析,给出形状时变引起的损伤场与地表移动的动态演化过程,并对比了非时变以及施工分析结果。研究表明,损伤时变分析可得到连续变化的位移及损伤演化图,相比非时变的常规分析和施工分析能更好地模拟连续施工,为工程施工分析与预测提供更加科学和有效的手段。为实现开采过程的经济和安全,应该采用损伤时变力学的分析方法。

This paper is to research time-varying body whose shape is varying with time. By combing time-varying mechanics and damage theory, variable damage parameter which correlated with variational course is introduced. Then the damage-time-varying analysis method is established. For the rock mass, elastic damage-time-varying constitutive equation is derived, and numerical analysis of this method is established by the virtual work principle. In numerical analysis, time-varying effect is considered by applying virtual time-varying non-balanced load which obtained by original stress system analysis. By damage-time-varying computer simulation analysis of mining process of one underground coal bed, dynamic evolution of damage field and surface subsidence due to shape varying are obtained, and comparison of time-varying and non-time-varying analysis and construction analysis is studied. The research shows that continual displacements and damage evolution can be obtained by damage-time-varying analysis which is more reliable to simulate continual construction process than normal and construction analysis. It is a scientific and effective method in prediction of engineering construction. In order to realize economy and security, it is instructive to use damage time-varying method in underground mining analysis.