采动影响下风井破坏原因分析

Research of the damage of ventilating shaft affected by Mining

在受采动影响情况下,利用概率积分与Drucker-Prager准则相结合的方法判断风井的破坏位置,因风井的破坏往往发生在岩层与岩层,或基岩与松散层交接面处,故该方法并不能从理论上说明破坏的原因.风井的破坏与否,与风井穿过的岩层的力学性质、岩层之间的胶结程度、岩层所处的深度有关,水平移动值的大小也与深度有关.因此,各岩层的水平移动值会有所差异.如果下层位岩层与上层位岩层胶结程度弱,那么,下层位岩层的水平移动传递到上层位岩层的可能就小,两个岩层之间水平移动值的差异大,也即水平变形大,会引起赋存在岩层内的地下构筑物破坏.工程实例验证了这种判断方法的可靠性.

By using the method of the probability integral in combination with the D - P （ Drucker - Prager） criterion, the damage scale of the ventilating shaft affected by mining is determind. In engineering practice, the damage of the ventilating shaft always occurs in the plane between rock strata and rock strata or the plane between bedrock and alluvial. But this method does not analyze why the ventilating shaft is damaged. Wheth- er the ventilating shaft is destroyed or not, is related to the mechanical properties of rock gone through by the ventilating shaft, the cementation between rocks and the depth of rock. The value of the horizontal displace- ments is related to the depth of the rock, so the value of the horizontal displacements is different between the rocks. If the cementation is weak between the lower rock and the upper rock, the value of the horizontal dis- placements between the two strata will be largely different. That it is, horizontal deformation is conspicuous, which will cause the destroy of the ventilating shafts within the rock mass. Engineering example shows that this method is reliability.