松软破碎硐室群围岩稳定性数值分析

Numerical Analysis on Surrounding Rock Stability of Soft-broken Chambers

为了确定平顶山矿区某矿井底车场硐室群加强支护的范围,给硐室加固提供技术支持,运用大型数值计算软件对矿井副井附近的硐室群开挖后围岩的应力场、位移场、破坏区进行了分析。研究表明:巷道开挖后,围岩应力重新分布,巷道两帮围岩出现生应力集中区和塑性破坏区。在巷道交叉处和巷道拐角处,二次应力场进行了叠加,叠加后部分区域的应力峰值达到原岩应力的2～3.17倍,围岩塑性破坏区域加大。硐室群的稳定性不同于单个巷道、硐室,存在集中应力叠加现象,在巷道交叉口和拐弯处尤其明显,巷道间距过小时,这种应力集中叠加会造成巷道稳定性控制困难。

To determine the supporting area of shaft station chambers in one of Pingdingshan mines and to provide the technology for chambers supporting, the paper uses a numerical calculation software to analyze the stress field, displacement field, and disturbed field of surrounding rock when the chambers have been opened in the vicinity of subsidiary shafts. The study shows that stress of surrounding rocks is redistributed. Stress concentration zone and plastic failure zone appear at the sides of roadways. In the junction and comer of roadways, superposition of secondary stress fields happens. The peak stress of some areas reaches 2-3.17 times of the original stress. The plastic failure zone becomes wider. The stability of chambers is different from the single roadway or room, since there is the superposition of stress, especially in the junction and corner of roadways. When the distance between roadways is too small, the stress superposition would make it difficult to control the stability.