综采面过陷落柱采动应力与柱体应力相互影响模拟研究

Simulation of interaction between mine-induced stress and stress of collapse column with fully-mechanized working face advancing

为了确保综采工作面安全通过陷落柱,采用数值模拟方法研究工作面推进过程中采动应力及陷落柱体应力随工作面推进的变化情况及相互影响。研究表明：陷落柱体应力和工作面采动应力的相互影响作用可分为弱、中、强3个影响阶段,3个阶段的范围分别为工作面距离陷落柱150~100 m,100~50 m和小于50 m。不同阶段关注重点不同：在弱影响阶段,采动应力开始对陷落柱体应力产生影响,在此之前需完成陷落柱加固;在中影响阶段,陷落柱对采动应力的影响开始显现;在强影响阶段,互相影响强烈,需加强顶板管理。根据研究结果,确定了K8403工作面顶板加强支护范围、陷落柱预加固时间及强度,实践表明加固效果良好,现已安全通过陷落柱。

To ensure the safe passage of the collapse column in the fully-mechanized top-coal caving mining face, the numerical simulation of the interrelation between the mine-induced stress and stress of collapse column was conducted. The results show that the interaction effect between the mine-induced stress and stress of collapse column can be divided into three stages： weak sub-stage, medium sub-stage and fierce sub-stage, the range of whose distance between the working face and the collapse column are 150-100 m, 100-50 m and less than 50 m respectively. Focal points differ in these three stages： in the weak sub-stage, the collapse column should be pre-reinforced, when the mine-induced stress begins to exert an effect on the stress of the collapse column; in the medium sub-stage, the stress of the collapse column starts to impact the mine-induced stress; and in the fierce sub-stage when the interrelation becomes fierce, the roof management should be strengthened. According the above research, the supporting range of roof in the K8403 working face, and the time and strength of the collapse column pre-reinforcement were identified. Meanwhile, the field practice showed that pre-reinforcement of the collapse column had a positive effect and ensured the safe passage of the collapse column.