The Researchofthe Influenceof The Tunnel Excavationon Existing Hgh-risei Buildings

The project of underground railway eases the traffic pressure on the ground but causes many problems.The movement and deformation of the land caused by the underground railway project affect the buildings on the ground and pipelines under the ground,especially the high-rise buildings.Therefore it’s significant to study the influence of the movement and deformation of the land on the high-rise buildings and take some measures to ensure the safety of the buildings.There are so many methods to study the influence of the tunnel excavation of subway on buildings.And the finite element method is widely used because of its universality and simplification.This passage introduces the deformation mechanism of the land caused by the tunnel excavation and the influence on surrounding buildings.The paper also studies the basic theory of the finite method and the key problems in the tunnel excavation simulation.This passage finally uses the software ABAQUS to simulate the tunnel excavation of subway in Jinan.It analyzes the surface subsidence caused by the tunnel excavation in different burial depth and distance and finds the influence on the surrounding buildings.The conclusions are shown as follows:(1)The displacement of tunnel after excavating,mainly appears in the soil around tunnel.The top soil of the tunnel has large longitudinal displacement due to the effect of gravity of the upper soil and buildings.The lateral soil pressure makes the model extruding inward which causes the displacement of the bottom of the tunnel has a upward tendency and the left and right sides of the tunnel appears larger horizontal displacement.(2)For the simulation of the tunnel with different buried depth,the results show that the maximum displacements of the building decrease at first and then increase with the increase of tunnel’s buried depth.The maximum displacements of the building get a minimum value at the depth of 18 meters,so the best buried depth is 18 meters.At the same depth,the displacements increase and the rates of the change decrease with the decrease of the distance from the node to the central axis of the building.(3)For the simulation of tunnels with different distances to the building,the results show that the farther the distance is,the smaller the longitudinal displacement of the building and the change rate of the building’s displacement is.The maximum longitudinal displacement appears when the central axis of the tunnel is at the one of the building.The maximum subsidence value of the building is less than 20 millimeters with the distance of more than 20 meters.The best distance of the tunnel excavation should be 20 meters away from building.