深厚粉细砂地层基坑工程中双排SMW工法桩的设计与施工

Design and Construction of Double Row SMW Method Piles in Deep Excavations in Thick Silt and Fine Sand Strata

国内基坑工程中型钢水泥土搅拌墙的应用越来越多,但在不加支点的双排桩支护体系中的使用比较少见。基于佛山市顺德区某一基坑工程,针对该地区深厚粉细砂的软土地层,结合建设单位的紧迫需求,阐述了不加锚杆及支撑的双排型钢水泥土搅拌桩作为围护结构的设计思路与施工措施。根据基坑支护的典型剖面,利用大型二维有限元软件PLAXIS进行了计算,将其与基坑监测数据进行对比,可知在深厚粉细砂地层中,双排型钢水泥土搅拌桩是可行的,可为类似项目提供参考。

The soil-cement mixed wall inserted with medium sized hot rolled steel beams has received more and more applications as the deep excavation supporting structures.Since the rare pile will resist the uplift load,the reinforced soil cement mixed wall has not been widely used as the supporting structure without horizontal bracing.This paper presents the application of double row piles with soil cement mixed wall without ground anchor or other horizontal supporting structure for a deep excavation project in Shunde District of Foshan City.The thick silt and fine sand soils are predominant at the project site.Both design principles and construction methods are introduced in the paper.The two-dimensional finite element software PLAXIS was used to analysis the typical supporting section.The construction monitored data were also compared with the numerical analysis results.It is concluded that the double row piles with soil cement mixed soil wall could be used as a supporting structure in the deep excavation in thick silt and fine sand layer.