青岛凯悦中心格栅式MC桩支护及变形分析

Support Technology and Deformation Analysis of Grid-MC-pile in Qingdao Capland Center

将水泥土重力式挡墙支护模型与双排桩支护模型结合起来,组成格栅式MC桩组合支护、止水体系,成功应用于青岛凯悦中心深基坑工程。应用平面有限元法模拟基坑开挖过程计算出各工况的变形值,与基坑实测变形进行对比分析;并运用不等时距曲线反映了基坑变形趋势,探讨了每道工况支护结构的内力调整过程,分析了支护结构的变形性状。结果表明该支护体系能增加整体稳定性,更好地控制基坑变形;另外提出"护脚台"的概念,可有效限制支护桩侧向滑移、克服"吊脚桩"现象。

Grid-MC-pile composite support and water stop system is successfully applied in deep foundation excavation of Qingdao Caplaad Center, which is combined of cement-soil gravity wall and double-row-pile. And plane finite element method is used to simulate excavation process and calculate the corresponding deformations. Furthermore the calculated deformations are costively analyzed with the me.asured ones. The use of varying time-distance curve reflects the deformation trend of supporting structure. With this, the adjustment process of internal stress is discussed and the deformation characteristic of supporting structure is analyzed. It shows that the support system can increase the overall stability and control the deformation better. At the same time, concept of supporting foot step is put forward, which can limit lateral slip of the supporting piles and overcome phenomena of hanging foot pile.