【摘要】 通过对软土中相邻基坑在交叉施工条件下相邻区域围护结构监测数据的分析,明确了围护结构受邻近基坑开挖施工影响受力变形的发展特点。结合全工况有限元模拟,考察了交叉施工对相邻支护结构的影响机理,并对支护结构上土压力受交叉施工影响进行了分析。研究得出如下结论:受邻近隧道基坑开挖卸载影响,相邻基坑间有限土体位移场有向较深侧基坑"倾倒"的趋势,从而引起主体基坑相邻侧的挡土结构侧向位移、支撑轴力和墙后土压力减小;有限土体土压力与挡墙位移之间的变化关系与经典土压力理论不一致,值得作进一步理论分析。更多还原

【Abstract】 Based on the analysis of monitoring data from a soft soil retaining structure under the condition of cross excavation and construction with an adjacent foundation pit, the deformation evolution characteristics of the retaining wall is identified to consider the effect from adjacent excavation construction. Combined with the whole-process finite element simulation, the mechanism of the interaction between the two adjacent retaining structures under cross construction is further investigated. The impact of cross construction on the earth pressure on the retaining wall is studied. The conclusions are made as follows. Due to the unloading effect from the adjacent tunnel foundation pit excavation, the in-between soil of the adjacent foundation pits tends to “dump” to the deeper foundation pit side, causing a reduction in the lateral displacement of the first-excavated retaining structure. The axial force of lateral struts and the earth pressure on the retaining wall of the first-excavated foundation pit are also reduced. The relationship between the earth pressure and the displacement of the retaining wall is not consistent with classical earth pressure theory, indicating that a revision of the earth pressure theory is necessary for adjacent excavation cases.更多还原