西安地铁某车站深基坑开挖变形特性分析

为了确保基坑开挖中周边环境的安全，以西安地铁某车站深基坑开挖为例，运用ABAQUS软件建立三维模型模拟开挖对周边地表沉降和围护结构变形的影响，重点研究开挖中周边地表的沉降分布规律和围护结构变形的规律，并与现场实际监测数据进行对比分析。结果表明：地表沉降的实测值比模拟计算值大，但变化趋势基本一致；在基坑开挖过程中，地表最大沉降位置距离基坑边缘约11 m处，最大值为3.298 mm；围护结构水平变形沿开挖深度的变化曲线呈抛物线形，最大水平位移位于基坑最大开挖深度的 1/2 处，最大水平位移为11.05 mm，距基坑长边边缘0~25 m及短边边边缘0~22 m范围内的地表沉降最大，施工监测中应重点关注。

Analysis of the deformation characteristics of a deep foundationpit excavation at a Xi′an subway station

To ensure the safety of the surrounding environment in the excavation of foundation pits, taking the excavation of a deep foundation pit at a Xi'an subway station as an example, ABAQUS was used to establish a three-dimensional model to simulate the impact of excavation on the surrounding surface settlement and the deformation of the retaining structure. This study focused on the distribution of the surrounding surface settlement and the deformation of the retaining structure and compared the simulation results with actual monitoring data to guide site surface settlement monitoring. Analysis results show that the measured value is larger than the simulated value, but the change trend is the same. In the process of foundation pit excavation, the maximum ground settlement occurs at 11 m from the edge of the foundation pit, the maximum value being 3.29 mm; the horizontal deformation curve of the retaining structure along the excavation depth is a parabola, the maximum horizontal displacement occurs at 1/2 of the maximum excavation depth of the foundation pit, and the value is 11.05 mm. The ground settlement within 0~25 m from the long edge and 0~22 m from the short edge of the foundation pit is the largest, which should be focused on in construction monitoring.