Influence Of Metro Tunneling By PBA Method On Adjacent Pile Foundation And Reliability Analysis Of Bearing Capacity

Surrounding environment disturbed by the ground deformation and stress relieving induced by metro excavation. Especially in Beijing which the main ground traffic style is based on overpass and ring road, many existing overpasses will be crossed by tunnels and the normal use of them will be affected inevitably. As new construction climax of the metro lines is coming in Beijing now, the number of this phenomenon is increasing, and the following situation will become sharper. So it's very important to study on the inflluence of metro tunneling on adjacent pile foundation.The paper is based on engineering background of the Beijing Guomao subway station, abstracting the computation model. Through numerical simulation, study the influence of adjacent single pile and pile group by metro tunneling with PBA method and comparative analysis the single pile and pile group.Analysis the reliability of pile foundation bearing capacity by tunnel excavation, through the response surface method to solve the statistical characteristics of capacity loss. Use JC method work out the reliability index and reliability of pile bearing capacity and analyzing how some variables affect the reliability of bearing capacity.Introduce three kinds of reinforcement measures to the adjacent pile foundation with subway construction.Including partition measures, soil consolidation, pile reinforcement and underpinning. Take setting the partition piles for example, analysis the effects of the reinforcement.