土岩组合双排吊脚桩桩锚支护基坑变形数值分析

 随着基坑开挖方式、深度及工程地质状况的不同，出现了很多特殊形式的深基坑支护结构。在土岩二元结构地层条件下，双排吊脚桩桩锚支护方式的设计与施工经验很少。针对这种支护方式的设计与施工，以青岛市凯悦深基坑为例，对其进行变形及安全稳定性分析，利用Plaxis有限元软件模拟基坑开挖过程，并结合现场监测资料进行对比分析。结果表明：双排吊脚桩桩锚支护体系具有较大刚度，能够有效控制基坑变形及桩体位移，基坑位移主要发生在土体深度范围内。研究可以为此类支护结构设计的优化提供理论依据。

NUMERICAL SIMULATION ON INFLUENCE OF HETEROGENEITY ON MACROSCOPIC FRACTURE PROCESS OF ROCK FAILURE

Many special supporting structures have arisen in deep foundation pits corresponding to different excavation methods，depths and geological conditions. In strata of soil-rock dualistic structure，design and construction experiences are far from adequate in double-row end-suspended piles. The supporting system of Kaiyue deep foundation pit in Qingdao is taken as an engineering case to simulate the excavation process with the finite element software Plaxis. And then，comparative analyses are carried out between analytical results and in-situ monitoring data. The results show that such double-row end-suspended piles has more stiffness and can effectively control the deformation of foundation pit and the displacement of the pile，which mainly concentrates in the depth range of soil strata. The conclusions can serve as a theoretical reference for the optimal design of similar support structures.