基于接触面孔隙率的含水基岩井壁外荷载研究

Study on radial loads of mine shaft lining in rock aquifer based on porosity of contact surface

为更合理地设计井壁,在多孔介质孔隙率相关问题研究的基础上,提出了基于井壁与围岩接触面孔隙率np以及围岩径向卸载率η1的新井壁外载计算方法;分析了np和η1对井壁径向外载的影响。分析表明:随np增大孔隙水压力作用增强,随η1增大围岩压力影响降低,井壁设计与施工中应在避免接触面固体骨架受拉的前提下合理提高η1。

In order to form a more rational design of shaft lining, a formula was put forward, in which the porosity of contact surface between shaft lining and surrounding rock np and ratio of radial unloading of surrounding rock η1 was taken into account,based on study of porosity of porous media. The influence of np and η1 on shaft lining was analyzed. The analysis shows that the influence becomes strong with increase of ηp and the impact of surrounding rock pressure becomes weak with increase of η1. Raising η1 rationally under precondition of avoiding stripping of solid skeleton should be done in design and construction. The result of the new method is smaller than that of current method and smaller than the pore water pressure obviously.