高压旋喷桩施工过程中桩身开裂原因

Analysis of crack of high-pressure rotating jet grouting pile in levee anti-seepage engineering

为研究堤防防渗墙施工过程中高压旋喷桩桩身开裂问题,以堤身迎水坡潜在滑体为研究对象,借助AutoBank有限元模拟高压旋喷桩施工过程中浆液凝固前的静止浆压力对堤身稳定性的影响。通过计算对比施工前和施工过程中的边坡抗滑稳定系数的不同,发现由于堤身土质,灌浆压力、桩身位置等因素影响,险工段堤身出现抬起效应和劈裂效应,此时未凝固的水泥浆液大幅削弱堤身稳定性,堤身边坡的微弱滑移导致桩身在凝固成型前发生开裂。施工过程中应控制合适的浆压力,尽量避免产生抬起效应和劈裂效应,确保高压旋喷桩的桩身完整性。本文研究成果可为堤防防渗工程中高压旋喷桩的设计及施工提供相关借鉴。

In order to find the reason of the crack of high-pressure rotating jet grouting pile in levee reinforcing project,the potential sliding body on the upstream slope of the levee is analyzed.AutoBank FEA is used to simulate the influence of static slurry pressure before slurry solidification on the stability of embankment during the construction of high-pressure rotating jet grouting pile.Differences of anti-sliding stability coefficient of slope between the different working conditions indicates that lifting effect and splitting effect appear in dangerous section due to the influence of soil quality,grouting pressure,pile position and other factors.The unsolidified cement slurry greatly weakens the stability of the embankment body,and the weak slippage of the side slope of the embankment causes the pile body to crack before it is solidified and formed.Appropriate slurry pressure should be controlled during construction to avoid lifting effect and splitting effect as much as possible to ensure the integrity of the high-pressure rotating jet grouting pile.The research results of this paper can provide relevant reference for the design and construction of high-pressure rotating jet grouting piles in embankment anti-seepage engineering.