自由断面管幕法在饱和软土地区桂桥路站地铁工程的应用

Application of Pipe-roofing Method with Various Section Types in Metro Construction of Guiqiao Road Station at Saturated Soft Soil Area

为解决建筑空间拥挤、交通道路堵塞等一系列城市发展问题,开展地下空间开发和利用相关研究,并提出自由断面管幕法。饱和软土地区土层含水量大、压缩性高、自稳能力弱,目前在这些地区采用自由断面管幕法施工的工程案例较少。为此,依托上海市轨道交通14号线桂桥路站工程,针对饱和软土地区土层特性,开展带油脂的外锁扣管幕顶管顶进技术、软土地层土体水平加固技术和管幕内土体分层开挖技术等关键技术研究。研究表明,通过上述关键技术,可以确保管幕锁扣密封止水和有效连接,提高开挖土体的强度,减小施工对周围环境的影响。

In order to solve a series of urban development problems such as city overcrowding and traffic congestion,engineers have carried out researches on how to develop and utilize underground space better and proposed the piperoofing method with various section types.As a new underground excavation method,this method is used widely owing to its less influence on surrounding environment and controllable ground subsidence.Nevertheless,due to the high water content,high compressibility and weak self-stabilizing ability of saturated soft soil,there are few engineering cases using the pipe-roofing method in the above areas.Consequently,based on the project of Guiqiao Road station of Shanghai metro line 14,and in consideration of the characteristics of saturated soft soil,the technologies of the pipe-roofing method including pipe jacking,soil reinforcement and layered excavation inside the pipe-roof are researched.The results show that the key technologies mentioned above can ensure the sealing and connection of the pipe lock,improve the strength of the excavated soil and reduce the influence of construction on the surrounding environment.