充满配重水钻井井壁筒在泥浆中竖向结构稳定的理论研究

Theory study on axial structural stability of bored shafts filled with water

提出了被广泛采用的钻井法施工悬浮下沉井壁有其深度极限的概念,分析了泥浆中钻井井壁底接触岩石后的受力状态,建立了固井前泥浆中充满配重水井壁的力学模型,该模型类似于液体中的有底管状细长压杆.以能量法为基础,利用结构稳定理论和流体力学理论原理,推导了井壁结构轴向临界稳定高度的解析式,并给出了典型算例.强调了工程设计中利用该公式的注意事项,提出了井壁深度超过屈曲极限后可以改变井壁结构或改变井壁下沉方法的建议.最后,指出进一步研究这一问题的内容和方法.

The concept of depth limit for the method applied to sinking of shaft lining by means of floatation in shaft bering that was widely utilized in mine construction was put forward. The mechanical state of shaft lining was analyzed when its pan touching the base rock of shaft bottom, and the calculation model of shaft lining filled with water in mud before fixed was set up, which similar to a self-gravitating bar in liquid. Based on the energy method as well as the structure stability and hydromechanics theory, the analytical equation for axial critical height of shaft lin- ings filled with water was calculated and a typical example was persuasive analyzed. The attention to use the equation was emphasized in shaft design and its construction. The suggestion was given to change the structure of shaft linings or improve on the method of sinking shafts when the depth was up to its backing size. At last, its further research content and direction were pointed out.