基坑倾斜桩无支撑支护机理与工程应用

Supporting Method and Applications of Inclined Retaining Piles in Foundation Excavation

针对大面积、大长度基坑中所常用的传统内支撑技术存在耗材多、造价高、工期长、施工不便、支撑拆除困难且难以实现地下结构工业化建造的缺点和局限,研发了一系列倾斜桩组合支护结构,条件适当时可在变形可控的前提下实现基坑的无内支撑支护,从而形成绿色低碳的新型基坑支护技术。简要阐述倾斜桩无支撑支护的作用机理,并进一步介绍倾斜支护桩施工设备与施工工艺,最后通过典型工程案例阐明倾斜桩的技术优势。工厂实践表明,相比于传统支护方法,倾斜桩支护结构可高效、经济地控制基坑稳定与变形,显著缩短施工周期的同时可为大面积、大长度基坑的施工提供便利,具有显著的推广价值。

The traditional propped wall is often used in large area and long excavation,which has the limitation of materials waste,great cost,long construction period,inconvenient construction and difficulties in realizing the industrialized construction of underground structure.A series of inclined retaining piles that can eliminate the horizontal struts on appropriate conditions which thus can be termed strut-free retaining structure were developed.The new inclined retaining structure with the combined use of vertical pile and inclined pile,is a kind of green and low-carbon new technologies in excavations.This article analyzes the mechanism of the inclined retaining piles,and the equipment to drive inclined pile and construction technology of inclined piles are introduced.Finally,case histories of inclined retaining piles are presented to demonstrate their advantages.Compared with traditional propped retaining pile,the inclined strut-free retaining piles can efficiently and economically control the stability and deformation of excavation.Besides,they can significantly reduce the construction period and realize the industrialized construction,which provides convenience for the construction of large and long excavation.Engineering practice shows that the inclined strut-free retaining structure can be applied widely in the future.