在连续基坑群同时开挖时,受施工条件所限,基坑设计的关键要从强度控制转变为变形控制.以某动车段大型厂房内软弱土层中连续基坑群为研究对象,分别从连续基坑群开挖过程中不同开挖顺序对不同位置深层位移的影响分析,后开挖基坑对先开挖坑支护结构变形研究和不同的开挖顺序对周边地表沉降的影响分析3个方面,对临近基坑及围护结构的影响效应问题进行数值研究.研究结果表明:连续基坑开挖过程中易引起周边土体向正在开挖的基坑方向位移,而且有一定的累加作用;基坑工程中相邻基坑的开挖顺序对所有基坑开挖之后的最终变形影响不大;连续基坑群在开挖的过程中,间隔施工有一定的优点.
In the excavation of group foundation pits, the key of the foundation pits design should change from the strength control to deformation control, due to the limited conditions of foundation pit construction. Taken the excavation of group foundation pits in a great workshop with soft soil layer as the research object, the numerical simulation of the effect of adjacent excavation and retaining structure was studied, from the analysis of effect of different excavation sequence on the deep displacement in different position, the deformation study on effect of the later excavated foundation pit on the supporting structure of the earlier pit, and the analysis of the influence of different excavation sequence on the surrounding ground settlement, respectively. The results show that the surrounding soil will move to the excavating pit under the continuous excavation process, and there is a certain cumulative effect. The excavation sequence has little effect on the final deformation in the adjacent foundation pits. Interval construction has certain advantages in the excavation process of group foundation pits excavation.