苏州地区软土地层深基坑侧向土压力分布规律研究

Distribution of Lateral Earth Pressure Induced by Deep Excavation of Soft Ground in Suzhou

为研究软土地层深基坑侧向土压力分布规律,依托苏州市轨道交通5号线长江路车站基坑开挖工程,采用增量法理论和数值模拟分析方法,对软土地层深基坑开挖过程中地下连续墙的侧向土压力分布规律进行分析。结果表明:施工过程对地连墙墙体的弯矩影响较大,为保证基坑围护结构安全,采用增量法计算侧向土压力时需考虑施工过程的影响;作用于地连墙上真实土压力分布形式呈三角形;苏州地区软土地层侧向土压力系数K建议取值范围为0.3~0.7。得到的苏州地区软土土压力分布模式可为该地区基坑开挖提供参考。

To further evaluate the distribution of deep excavation lateral earth pressure,the project of Yangtze River Road Station for Suzhou Metro Line 5 was selected.The characteristics of lateral earth pressure on the diaphragm wall during excavation process was evaluated by theoretical analysis,numerical simulations,and field measurements.Observations indicate that the excavation process has serious impacts on the bending moment of diaphragm wall,which should be considered for calculating the lateral earth pressure by using the increment method.The real distribution of lateral earth pressure on the diaphragm wall performs a triangular type,and the recommend range of the lateral earth pressure coefficient K for Suzhou soft ground was obtained as 0.3~0.7.The distribution model of soft soil pressure in Suzhou area can provide reference for foundation pit excavation in this area.