地下连续墙穿越砂质粉土层施工技术

Construction Technology of Diaphragm Wall Crossing Sandy Silty Soil Layer

砂质粉土地层在连续墙成槽施工时容易产生坍塌现象,不仅造成地下连续墙自身质量差,而且影响后期主体结构施工进度、质量。徐州市城市轨道交通2号线一期工程市行政中心站采用明挖法施工,围护结构地下连续墙施工需穿越不良地质(19m厚砂质粉土层),在徐州地区尚属首例。针对该地质情况,从施工工艺、施工设备选型、泥浆护壁、土体改良等方面介绍了地下连续墙穿越砂质粉土层的施工技术,并取得了良好的效果,以期对类似工程设计与施工有一定借鉴意义。

Sandy silt layer is prone to collapse when diaphragm wall is grooved, which not only causes poor quality of diaphragm wall itself, but also affects the construction progress and quality of main structure in later period.Open-cut method is adopted in the construction of the municipal administrative central station of Xuzhou Urban Rail Transit Line 2 Phase I Project.The construction of diaphragm wall of enclosure structure needs to pass through unfavorable geology (19 m thick sandy silt layer), which is the first case in Xuzhou area.The author mainly introduces the construction technology of diaphragm wall through sandy silt layer from the aspects of construction technology, selection of construction equipment, mud retaining wall and soil improvement, and achieves good results, with a view to providing some reference for similar engineering design and construction.