Numerical Simulation And Analysis Of The SPB Shield Tunnel Construction In Soft Soil Stratums

With the increasing of the population and the developping of cities, resource and environment are the common problems that every country is facing.It's necessary to ask for space from underground. The development of urban tunnel can solve the pro-blems of population explosion, subaerial traffic jam, etc, and can economize costful soil resource. Because of shield driven method's unique characteristics and advantages such as intell-igence,safety and quickness,etc. It is necessary to construct underground tunnel in relatively weak statum by it. SPB shield is the most advanced construction method of constructing under-ground tunnel in relatively weak statum, but it is in primary stage in our country. So, summarizing SPB shield construction technology is practical to enhance our country's shield cons-truction technology and can provid some references to other similar projects.On the base of the review of anteceded research results and in-situ monitoring results, the importance of the stability of excavation surface was recognized. Pressure status in excavation surface differs when the geological condition,water table or the burial depth of tunnel changes.The auther analysis different soil stratum's stability in theory,and study stability in excavation surface under different...