微风化岩层地下连续墙优质高效施工技术

High Quality and Efficient Construction Technology of Underground Continuous Wall in Slightly Weathered Rock

针对目前地下连续墙入岩后施工经验相对较少,尤其是进入微风化地层后地下连续墙施工经验更少的情况,以深圳某跨海通道工程上软下硬复合地层地下连续墙施工为工程背景,以提高施工效率、保证地下连续墙施工质量为前提,对微风化岩层地下连续墙优质高效施工技术开展研究。通过优化地下连续墙入岩后机械配套选型,提高成槽质量及效率、改良泥浆护壁配合比,提高泥浆护壁效果、对现有施工机械改进,减少涡流防止上部软土塌方等多方面工作,对原有施工工艺进行优化,形成了一套双轮铣结合重锤破岩、成槽机取土、钠基泥浆护壁的复合地层地下连续墙高效成槽方法,有效确保进入微风化岩层的地下连续墙施工进度及质量。

In view of the current situation of relatively scarce the construction experience of diaphragm wall under the condition of rock layer,especially the even more scarce construction experience when entering into the slightly weathered rock stratum,based on the construction of diaphragm wall in an upper-soft lower-hard composite stratum in a cross-sea passage project in Shenzhen,the construction technology of diaphragm wall under the slightly weathered rock stratum is studied on the premise of improving the construction efficiency and ensuring the construction quality.And by optimizing the selection of mechanical equipment when the diaphragm wall entering into the rock layer,improving the quality and efficiency of the groove formation,improving the mud wall protection formula,improving the mud wall protection effect,improving the existing construction machinery,reducing eddy current and preventing the collapse of the upper soft soil,the original construction technology has been optimized and a set of high-efficiency groove-forming method of composite stratum diaphragm wall with two-wheel milling combined with heavy hammer breaking rock,trencher taking soil,sodium-based mud wall protection has been formed,which can effectively ensure the construction progress and quality of the diaphragm wall when entering into the slightly weathered rock stratum.