基于主应力表征参量的底板破坏影响模拟研究

Simulation Study on Floor Destruction based on Principal Stress Characterization Parameters

为了研究晋华宫煤矿底板破坏影响程度的问题,依照工程实际采用FLAC^(3D)软件模拟该矿7-4~#煤层开采过程中底板主应力分布及变形情况,应用主应力差和主应力比这2个力学表征参量,分析了一侧采空与两侧采空条件下煤柱底板主应力参量分布规律。数值模拟结果表明,煤柱附近的主应力差呈蝶形分布,采空区周围主应力比以包络圈形式分布。通过对一侧采空与两侧采空底板主应力表征参量的对比分析,发现两侧采空比一侧采空的煤柱附近具有更高的主应力差集中现象,最终得出底板破坏深度可达5 m,影响深度可达43 m,与现场所得数据吻合,验证了用主应力表征参量——主应力差和主应力比来分析底板破坏的合理性。

In order to study the influence degree of the floor failure in Jinhuagong Coal Mine,in accordance with the engineering practice,FLAC^3D software was used to simulate the main stress distribution and deformation of the floor during the mining of7-4^#coal seam.By using the two mechanical parameters of main stress difference and main stress ratio,the distribution of principal stress parameters of coal floor under the conditions of one side mining and two sides mining were analyzed.The numerical simulation results show that the principal stress difference near the coal pillar is butterfly-shaped,and the principal stress ratio around the goaf is distributed in the form of enveloping circle.Through the comparative analysis of the characteristic parameters of the principal stress on the floor on one side and two sides,it is found that there is a higher concentration of principal stress difference near the coal pillar which is excavated on two sides than on one side,finally,it is concluded that the failure depth of the floor can reach5m and the influence depth is up to43m,which is consistent with the field data,the reasonableness of using principal stress to characterize the parameters,namely,principal stress difference and principal stress ratio to analyze the failure of the floor is verified.