基于ABAQUS软件对苏州某大型基坑监测的模拟与分析

Numerical Analysis of a Large-Scale Deep Excavation in Suzhou Using ABAQUS Software and Construction Monitoring

城市大型基坑项目越来越多,对基坑开挖的数据进行监测分析及对变形进行研究显得尤为重要。基于苏州某大型基坑工程实例,通过选取具有代表性的监测点对其开挖过程中的桩顶累计竖向位移、桩顶累计水平位移、周边地表累计沉降等数据进行监测分析,并采用ABAQUS软件对基坑进行模拟分析。结果表明:采用三轴搅拌桩内插PHC管桩、钻孔灌注桩、斜拉旋喷锚索、钢管斜抛撑、钢筋混凝土支撑结合锚喷放坡土钉墙的支护形式对大型基坑是可行的,围护结构桩顶位移、坑外地下水位沉降、周边管线、建筑沉降实测值等均小于报警值。根据ABAQUS数值模拟分析结果可知,桩顶累计竖向位移模拟值与实测值规律性较一致,表明ABAQUS软件用于基坑开挖安全性预测是可靠的。

Nowadays,there are more and more large-scale deep excavation projects in cities,and it is particularly important to monitor and analyze the data of the deep excavation and to study the deformation.Based on an example of a large-scale deep excavation project in Suzhou,the accumulated vertical and horizontal deflections at the pile top and the accumulated settlement of the surrounding ground surface during the excavation process were monitored.The monitored data were compared with the numerical analysis results by using software ABAQUS.The results show that the feasibility of the different excavation supporting methods,such as,three-axis mixed soil-cement column inserted by the PHC pipe piles,bored cast-in-place reinforced concrete piles,inclined jet grouted ground anchors,steel pipe rakers,reinforced concrete strut combined with soil nail wall with shotcretes.The displacement at the pile top of the supporting structure,the groundwater level variation outside the excavated area,the surrounding pipelines,and the actual measured values of the settlement of the building are all less than permitted values.The results of the ABAQUS numerical analysis show that the cumulative vertical displacement value at the pile top is consistent with the actual monitored data.