常州润华环球中心深基坑支护效果分析

常州润华环球中心基坑工程一区开挖深度达18 m，采用钻孔灌注排桩和内支撑作为支护结构。基坑施工过程中对基坑顶部的沉降位移和水平位移进行了监测。基坑工程施工结束后基坑顶部的沉降位移和水平位移达到稳定值（分别为25 mm和40 mm），整体支护效果显著。但在基坑第三次开挖结束后第二道支撑构筑完成之前，基坑顶部的沉降位移和水平位移速率突然增大，直至第二道支撑构筑完成后增速才缓慢降低。提高第二道支撑的标高有利于降低基坑的变形，提高支护效果。

Supporting Effect Analysis on Deep Foundation Pit of Runhua Globe Center in Changzhou

The depth of the foundation pit area 1 of Runhua Globe Center reached 18 meters, and it was constructed by using cast-in-situ bored piles and inner bracing structure. Vertical settlement and horizontal displacement at the surface around the deep foundation pit were monitored during and after the foundation engineering construction. By the completion of the construction, the subsidence and horizontal displacement reached the stable values of 25mm and 40mm respecively, the supporting effect was coincided with the design requirements. However, monitored values increased suddenly just at the time after the third excavation and before the second support completion and the growth rate were slowly decreased until the second supporting structures were completed. It is advantageous to reduce the deformation of foundation pit and improve the supporting effect by increasing the designed elevation of the second supports.