富水粉细砂地层中护壁泥浆材料配比的优化

Optimization of Slurry Material for Wall Protection in Silty Fine Sand with Generous Water

地下连续墙在以淤泥、粉细砂层地质为主,地下水丰富的江浙沪地区施工时,因传统护壁泥浆携砂能力过剩而造成废浆率大、沉渣厚和成墙质量差等问题。为有效提高地连墙施工质量,开展了低固相地连墙泥浆配制试验研究,通过优选增黏组分、成膜粉体助剂和膨润土,制备匀质性好、滤失量低、泥膜致密和挟沙能力适中的工程用地连墙护壁泥浆,掌握了低固相地连墙护壁泥浆制备工艺等关键技术。基于苏州地铁8号线的工程应用表明:利用该工艺制备的低固相地连墙护壁泥浆沉渣厚度低于100 mm,泥浆循环使用损耗率低于20%,成墙质量得到明显提升。

There are problems such as excessive carrying capacity of traditional mud for wall protection,large waste slurry rate,thick sediment and poor wall quality,when the diaphragm wall was constructed in areas,where silt and fine sand are the main geology and groundwater is rich.In order to effectively improve the construction quality of diaphragm wall,experimental on slurry preparation of diaphragm wall was carried out.By optimizing the viscosity components,film-forming powder additives and bentonite,the slurry with good homogeneity,low filtration loss,dense mud film and moderate sand carrying capacity for engineering land was prepared,and diaphragm wall slurry application were mastered.The application of Suzhou Metro Line 8 shows that the slurry preparation process of diaphragm wall is simple,the sediment thickness is less than 100 mm,the slurry recycling loss rate is less than 20%,and the wall quality is significantly improved.