多头搅拌桩与高压摆喷桩在截渗工程中的应用

Application of Multi-head Stirring Pile and High-pressure Rotary Jet Grouting Pile in Cut-off Seepage Project

结合太仓市应急水源地工程实例,比较分析了多头搅拌桩与高压摆喷桩两种施工方法在围井试验中的检测结果,利用AUTOBANK(水工有限元分析系统)建立渗流稳定及抗滑稳定模型,说明模型建立的原理及采用的公式,计算各种工况下的渗流稳定及抗滑稳定。结果表明:在土坝渗流中,高压摆喷桩与多头搅拌桩形成的连续墙,渗透系数相近,且均满足防渗的设计要求;高压摆喷桩形成的桩体连续性、芯样的完整程度差,喷浆孔位置薄弱;多头搅拌桩形成的墙体成墙均匀,相对搭接好,且施工工艺不会破坏原有土坝的完整性,并在工程施工质量、工程造价、施工功效方面具有显著的优越性,对环境的影响小。基于多头搅拌桩的特点及优越性,该工法将会广泛应用于各种实践的截渗工程中。

Based on the engineering example of the emergency water source area in Taicang, the measured results in the well test using the multi-head stirring pile and high-pressure rotary jet grouting pile methods were compared, and the AUTOBANK（hy- draulic finite element analysis system） was used to establish the seepage stability and anti-sliding stability models. The principle and main formula of the models were introduced, and the seepage stability and anti-sliding stability were calculated under differ- ent working conditions. The results showed that（l） in the earth dam seepage, the high-pressure rotary jet grouting pile and multi-head stirring pile form a continuous wall which has a uniform permeability coefficient and can meet the design require- ments of anti-seepage; （2） the pile body formed by the high-pressure rotary jet grouting pile is characterized by？ poor continuity and core sample completeness and weak spray hole positiomand（3） the wall formed by the multi-head stirring pile is even, has good relative overlap, and the completeness of the dam is not affected by the construction technology. Moreover, the muti-head stirring pile has remarkable superiority in the construction quality,cost,and construction efficiency and low impact on the con- struction environment. Consequently, the multi-head stirring pile can be widely used in all kinds of cut-off seepage projects.