地连墙槽壁加固深度和宽度计算方法研究

A method for determination of reinforcement width and depth of trench face of diaphragm wall

地连墙槽壁加固深度和宽度既要满足槽壁土体整体稳定性要求,又要满足加固体抗滑(剪)、抗倾覆和抗弯能力要求。首先分析了槽壁加固条件下影响槽壁稳定性的各影响因素与槽壁稳定性安全系数的关系,总结出加固体深度和宽度是关键影响因素,也是工程施工前需要求算的重要控制参数。其次提出了搅拌桩加固体抗滑(剪)、抗倾覆和抗弯能力验算原则和安全性判定标准,也提出了搅拌桩加固深度(长度)和宽度计算方法和在搅拌桩桩顶插入钢性筋并嵌固于导墙中和搅拌桩平面外拱布置等方法以提高槽壁稳定性的措施。利用工程实例,对文中提出的搅拌桩加固深度(长度)和宽度计算方法进行了演算,也对提出的搅拌桩桩顶插入钢性筋并嵌固于导墙和搅拌桩平面外拱布置提高的槽壁稳定性安全系数也进行了演算。最后提出了课题研究展望。

The reinforcement width and depth of trench face soil body of diaphragm wall should satisfy not only the requirement of stability of trench face but also the requirement of anti-sliding(anti-shearing), anti-capsizing and anti-bending capability of reinforcement body. The paper first analyzes the relationship between the lots of influencing factors and the stability safety factors of trench face, and it also sums up the key influencing factors and the important controlling parameters which are the reinforcement width and depth. Then it puts forward the checking principle and the safety criteria for the anti-sliding(anti-shearing), anti-capsizing and anti-bending capability, and also presents the calculation methods of width and depth(length) of mixing pile reinforcement body. In addition it puts forward measures which can upgrade the stability of trench face by means of inserting steel material into mixing pile top and embedding steel material in guide wall and arranging mixing piles into outer arch in the plane. The verification of calculation methods of mixing pile reinforcement width and depth is carried out, and the calculus of being upgraded stability safety factors of trench face by means of inserting steel material into mixing pile top and embedding steel material in guide wall and arranging mixing piles into outer arch in the plane is also given. Finally, it provides the research prospect on this topic.