基于SMP准则的定向钻扩孔泥浆压力计算  

Determination of the Mud Pressure in the Drilling Reaming Process Based on the SMP Failure Driterion

作　　者：朱建明[1,2] 赵沙沙[2] 江强 彭新坡[4] 

机构地区：[1]北方工业大学建筑工程学院,北京100144 [2]北京航空航天大学交通科学与工程学院,北京100191 [3]江阴市人民政府重点工程建设办公室,江苏江阴214400 [4]北京市建筑工程研究院,北京100039

出　　处：《地下空间与工程学报》2012年第4期756-760,771,共6页Chinese Journal of Underground Space and Engineering

基　　金：江苏省建工局科研资助项目(2009132)

摘　　要：定向钻施工中泥浆压力是孔壁稳定的关键因素,其计算公式一直是困扰定向钻施工设计的主要问题。文中基于SMP准则分析了定向钻扩孔过程中孔壁土体内的二次应力、应变场以及塑性区半径分布规律,推导出了最大泥浆压力的计算公式。基于SMP强度准则得到的最大孔壁内压和最优孔壁内压值明显大于基于M-C强度准则计算所得值,这说明了考虑中间主应力影响的SMP强度准则对提高最大孔壁内压和最优孔壁内压值具有重要的实际意义,此外,通过改变粘聚力和内摩擦角的大小,得到粘聚力对于最大孔壁内压的敏感性要大于内摩擦角,所以提高土体的粘聚力对孔壁稳定性更具实际意义。The mud pressure is the key factor for the hole wall stability in construction of the directional drilling, the formula of mud pressure is the main problem in design and construction. This paper analyzes the rules of the sec- ondary stress-strain and the radius of plastic zone in soil layer with the SMP failure criterion, deduces the calculation formula of the maximum mud pressure. The maximum pore pressure and the optimal pore pressure inside the wall based on the SMP failure criterion is significantly greater than those based on the M-C failure criterion. This shows that the SMP failure criterion considering the influence of the intermediate principle stress has a important practical significance to increasing the maximum pore pressure and the optimal pore pressure inside the wall, in addition, it can be found that the influence of cohesion to the maximum pore pressure inside the wall is more than the influence of internal friction through changing the value of cohesion and internal friction, so, increasing the cohesion has a practi- cal significance to the stability of the hole wall.

关 键 词：定向钻 SMP准则 塑性区半径 最大泥浆压力 

分 类 号：O319.56[理学—一般力学与力学基础]