非满配重水钻井井壁筒竖向结构稳定的理论研究

提出了国内广泛采用的悬浮下沉井壁钻井施工法有其深度极限的观点。分析了泥浆中的井壁筒在加入配重水(非满水)后井壁底接触岩石时的受力状态;结合国内悬浮下沉井壁钻井法的工艺特点,建立了泥浆中的井壁筒为有底管状自重压杆的力学模型;以能量法为基础,利用结构稳定理论和流体力学理论原理,推导了非满配重水井壁筒竖向结构稳定临界高度的解析式,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,并指出进一步研究这一问题的内容和方法。

Study on vertical structural stability of bored shafts filled part of water

The concept of depth limit for the method applied to sinking of shaft lining by means of floatation in shaft boring that is widely utilized in mine construction in China was put forward.The mechanical state of shaft lining filled part of water when its pan touching the base rock of shaft bottom was analyzed.Contacting with the technical characteristic of shaft lining sinking by means of floatation,the calculation model of shaft lining filled part of water in mud before fixed,as a self-gravitating bar in liquid,was set-up.Based on energy methods as well as the principle of structural stability theory and hydromechanics theory,the analytical equation for vertical structure stability critical height of shaft cylinder filled part of water was calculated.A typical example was persuasively analyzed.The attention to use the equation was emphasized in shaft design and its construction.Finally,its further research contents and direction are pointed out.