A New Technology Study On Tunnel Construction Of Natm Under Municipal Road In Guangzhou Region

In Guangzhou region,as a subway construction along with the gradual opening to promote the construction method,mining method is smaller damager on the surface,and it features the city market area is not greatly affected the normal operation, but also for flexible cross-section,and the construction speed is easier to control.Especially in the downtown area where the construction of the tunnel,shallow is a more appropriate, but also must participate in the election than the one of the methods.It is important to note that the effect shallow water shutoff construction quality will be directly related to the success or failure of tunnel construction.Guangzhou rich water due to the geological characteristics of thick sand on the use of shallow tunnel excavation method requires the use of advance support and add pre-reinforcement of soft soil treatment solution to soft ground and plugging problems.In this paper, two aspects of theory and practice study, by analyzing the field stratigraphic geological conditions, hydrological conditions, the surrounding environmental conditions, developed an effective method of tunnel excavation and grouting techniques, grouting materials and targeted analysis, selection, and finally to implementation of the project to achieve a fast, efficient and economical purpose.Through theoretical analysis and field practice test, improved grouting process, according to adjusted comparison test grouting materials, and through research found that the penetration of sub-excavation of pilot tunnel excavation method of improving water law, which successfully completed the shallow dark tunnel construction.Results of these studies use a similar approach in the Pearl River Delta tunnel construction has some reference and guidance. Meanwhile, design, construction, research and other departments also have some reference value.