砼芯水泥土复合桩在基坑支护工程中的应用与研究

Study of Cement-soil & Concrete Core Combined Piles in Excavation of Building Foundation

砼芯水泥土复合桩是一种新型的基坑支护方法,即在水泥土搅拌桩中插入钢筋混凝土预制小方桩,形成一种新的复合桩体,兼有受力和止水的双重作用,并采用两排中间用圈梁相连的门型结构提高了支护结构的受力特性。该支护方案在南京某深基坑工程中得到了成功应用。本文分析了该新方法的结构特点、简要介绍了其设计计算方法,并结合有限元数值模拟和实际的监测数据与排桩方案进行分析比较。研究结果表明,该新型基坑支护形式取得了良好的支护和经济效果,具有重要的应用前景。

Cement-Soil and R. C combined piles are a new measure for retaining and protecting excavations of building foundation, with R. C piles being inserted into Cement Deep Mixing piles. This new type of multiplex pile simultaneously has both functions of bear loadings and cutting off water. Use of Door-typed piles, with fore-and-aft rows connected with circular beam, can improve the mechanical function of retaining structure. This new technique has been applied successfully in a deep excavation in Nanjing. The design details of structures and computation results are presented in this paper. Comparisons are made between numerical monitoring data. It is shown that the new type of pile is a cost-effective retaining structure and can find wide application in deep exactions for building foundations.