玄武岩裸体斜井井筒围岩稳定性分析

地下井巷的开掘工作破坏了地层原岩应力的平衡状态,导致井巷周围岩体内应力的重新分布和应力集中,当集中应力超过井巷周围岩体强度时,将引起井巷围岩变形、松动垮落和底板鼓起等一系列矿压显现现象。显然矿压显现的剧烈程度不仅和矿山压力的大小有关,而且和井巷围岩自身的物理、力学性质也紧密相关。针对西南某在建矿井玄武岩裸体斜井井筒围岩的稳定问题,利用弹性力学和岩石力学的相关知识,采用理论分析和数值模拟相结合的综合研究方法,对井筒开掘引起的周边围岩内的最大集中应力以及最大集中应力和玄武岩岩体许用强度之间的关系进行了深入研究,得出了最不利情况下井筒周边围岩的最大集中应力仍然小于玄武岩岩体的许用强度、该段斜井井筒可以采用裸体巷道的重要结论,为现场的支护设计与施工提供了科学的理论依据。

Stability Analysis of Basalt Nude Inclined Shaft Surrounding Rock

The digging of underground laneway will destroy the balanced state of the initial rock stress，making the stress field around laneway redistribute and concentrate.When the concentrated stress is higher than the rock mass strength around laneway，it will cause ground pressure behaviors，for example surrounding rock deformation，loosening，floor heave and so on in laneway.Evidently，the severe degree of ground pressure behaviors is not only relevant to the rock pressure，but also interrelated with the physical and mechanical properties of the rock around laneway.Aiming at the stability of basalt nude inclined shaft surrounding rock of a under-construction mine in Southwest China，based on the knowledge of elasticity and rock mechanics，the comprehensive analysis method of the theoretical analysis and numerical simulation is adopted to analyze the highest concentrated stress of surrounding rock and the relationship between the highest concentrated stress and the approved strength.It is concluded that the highest concentrated stress of surrounding rock is lower than the approved compressive strength of basalt rock mass in the worst condition，the inclined shaft can take the shape of nude laneway，and it provides a scientific theory basis for the field support design and construction.