Study On Ground Settlement Due To Subway Construction With Cavern-Pile And CRD Method

With domestic cities and towns progress faster and faster, underground develop quickly. It is predicted that a great deal of urban metro at early-middle period foreground nowadays, in the 21st century that will be constructed on flourish underground engineering and at the same time many geotechnical problems will also come forth. Large land subsidence induced by metro tunneling can lead to that road surface, buried pipelines and buildings and so on are damaged. Furthermore, bad economic urgent realistic and personnel loss and social effect can be brought about. As a result, it is an important realistic problem that land subsidence induced by tunneling is forecasted and controlled so as to ensure the safety of close-by building and buried pipeline.Using shallow tunnel by excavation construct metro in cities, especially dense buried pipelines, structure in the confined groundwater, the large tunnel working face, the close regional tunnel and metro station, excessive construction procedure and node and so on. Without proper measure to control the ground subsidence and collapse, the close-by building and buried pipeline will be in danger. The article sum up and analyses all kinds of construction methods on metro station and regional tunnel. To study on CRD method and cavern-pile method. result in ground subsidence forecast, the excavation and support effect in construction process. In virtue of nonlinear characteristic of construction routine in underground engineering, aiming to land subsidence combined Finite Difference Theory, bring forward relative simulation method and built a dynamic numerical model with the uncoupled flow-mechanical approach in condition of shallow tunnel by excavation.It is availability in virtue of contrast the data in practice engineering to the numerical model. Discuss the rule as CRD and cavern-pile method. to construction. Detailed analyzing mechanic effect of the retaining wall pile on account of different construction method cross. It is good for the underground stability to control ground subsidence by cavern-pile method. in shallow tunnel by excavation. Present criterion controlled vault subsidence on the basis of vault and close-by building subsidence rule. On account of stress-softening characteristic of the soil, the instability failure that expand in unsubstantial region and go with the largish vertical and lateral distortion in soil when the slide come into being until the whole failure. It is focus to control wall rock stability in design and construction metro station and tunnel with shallow tunnel by excavation. The article put forward the Finite Difference Method that base on the strength reduction theory to analyze the safety factor and the possible soil failure region in the course of construction with CRD and cavern-pile method.To sum up the estimate criterion and method that construction result in buried pipelines distortion. Simulate and analyze the relation between concrete rain-waste pipe and ground subsidence, pipe stress distribution and safety. It point out the pipe hidden trouble in construction. Thus theoretical basis and guidance are provided to real engineering, at the same time, it is still necessary to more confirmed construction target.