灌注桩-钢管桩复合土钉墙组合支护体系的研究与应用

Research and Application of Pile-steel Pipe Pile Composite Soil Nailing Wall Composite Support System

随着城市建设的飞速发展,高层建筑日益增多,随之出现了大量超大、超深基坑,复杂的工程地质条件与周边建筑环境,给基坑支护工程带来了很多难题,单一的基坑支护体系往往已无法满足基坑稳定性要求。以北京市某基坑工程为例,介绍了一种新型组合支护体系——灌注桩-钢管桩复合土钉墙,通过与桩锚支护体系的对比研究,得出该组合支护体系在深基坑支护工程中的优越性。利用Midas GTS有限元分析软件,对基坑开挖过程进行模拟研究,对比分析了支护结构位移变形、基坑周边道路沉降等数值模拟结果与现场监测数据,结果表明:该组合支护体系对增强结构稳定性、控制边坡位移变形、减小土方开挖过程中对周边建筑环境的影响等方面具有良好作用。

With the rapid development of urban construction,high-rise buildings are increasing,and a large number of super-large and super-deep foundation pits,complex engineering geological conditions and surrounding building environments have emerged.It brings a lot of problems to the foundation pit supporting engineering.At the same time,the single foundation pit supporting system can not meet the requirements of foundation pit stability anymore.Taking a foundation pit project in Beijing as an example,a new type of combined support system--Pile-steel Pipe Pile Composite Soil Nailing Wall is presented.By comparing with pile-anchor support system,the advantages of the combined support system in deep foundation pit support engineering are obtained.And Midas GTS finite element analysis software is used to simulate the process of foundation pit excavation.The numerical simulation results of the displacement deformation of the supporting structure and the settlement of the road around the foundation pit are compared with the field monitoring data.The results show that the combined support system plays a good role in enhancing the stability of the structure,controlling the displacement and deformation of the slope,and reducing the influence of the excavation on the surrounding building environment.