长江低漫滩地区紧邻地铁深基坑既有建筑物加固技术

结合南京市河西地区紧邻地铁深基坑工程既有建筑物不同程度沉降开裂问题,提出超长钢管静压桩加固技术.为了提高房屋安全性,进一步提出工程静压桩和储备桩两道防线消险加固措施,在施工中分批次压入两道防线静压桩.通过监测加固前和加固后建筑物沉降变形,发现加固后建筑物受临近基坑施工影响显著变小,并且距离12 m处基坑施工的影响程度远小于距离220 m处基坑施工的影响程度.说明该加固方案有效降低了房屋的进一步沉降开裂问题,从而验证了长江低漫滩地区采用超长钢管静压桩提高建筑物抵抗变形能力的可靠性.

Reinforcement technology of existing buildings adjacent to deep foundation pit of metro in low floodplain area in Yangtze River

Based on settlement and cracking problems of existing buildings at Hexi district in Nanjing, a reinforcement technology of super-long steel tube static pile is put forward. In order to improve building safety, two lines of defense made by static piles and reserve piles were further proposed for reinforcement measures, and static pressure piles as the two lines of defense were applied in batches during construction. By monitoring the settlement deformation of the building before and after reinforcement, it is found that the reinforcement building is less affected by adjacent foundation pit construction. Especially, the influence of a foundation pit construction at a distance of nearly 12 m away is much less than that of a foundation pit construction at a distance of 220 m far away. It shows that the reinforcement method reduces effectively appearing disasters of further settlement and cracking of the existing buildings. Thus, the validity and rationality of applying super-long steel pipe static piles in the low floodplain area of the Yangtze River to improve the ability of buildings to resist deformation, has been verified indeed.