基于随机介质理论的深基坑开挖沉降变形研究

Settlement and Deformation of Deep Excavation Estimation Based on Stochastic Medium Theory

结合南宁轨道交通那洪立交站地铁车站深基坑的工程建设,基于简化的随机介质理论和沉降经验公式对地表变形进行预测,通过与监测值对比验证预测地表变形的可行性;通过对南城百货大楼的变形监测分析,讨论了基坑开挖导致紧邻建筑物沉降的规律及建筑物沉降变形与地表变形和基坑坑壁水平位移的相关性。结果表明:随机介质理论的预测值与监测值变化特征相一致,但监测值小于预测值;建筑物沉降变形特征与周围土体变形相一致,但变形时效相对滞后;基坑开挖和内支撑施工会对周围环境产生变形影响,导致周围地表和建筑物的累计沉降变形量出现波动。

The simplified stochastic medium theory and the settlement empirical formula were used to estimate the ground settlement in the deep excavation of Nahong Overpass Station of Nanning Rail Transit Project.The feasibility and accuracy of prediction ground subsidence are validated by the monitored data.The settlement of surrounding buildings causing by the deep excavation and the relationships among the building settlement,the ground deformation and the horizontal displacement of supporting structure of the deep excavation were analyzed.The results indicate that the predicted value by the stochastic medium theory is consistent with the characteristics of the monitored data,but the monitored value is less than the predicted value.The settlement characteristics of the building are consistent with the surrounding ground deformation,but it is relatively lagging with time.Both the deep excavation and the internal support construction will lead to deforming of the surrounding environment,causing fluctuations in the cumulative settlement of the surrounding ground and buildings.