Tunneling And Deep Soil Foundation Pit Excavation Finite Element Simulation

With the development of modern science and technology, social economy rapidlyforward, push the progress of urban development change with each passing day. In the rapiddevelopment of urban process, emerged the contradiction between population explosion withconstruction land tension. To solve the problem of the shortage of urban land, develop andutilize the underground space of urban rational and efficient, not only can ease this conflict,but also meet the special needs of social development. Problems such as surface subsidence,urban house demolition earth excavation, base slot excavation and slope support alwaysappear when we are in underground space utilization. How to development and utilize theunderground space under the high density buildings reasonable is can’t be ignored problem inthe process of city modernization.Based on the finite element analysis software COMSOL Multiphysics, this paperanalyzed tunneling excavation and deep excavation process in geotechnical engineering. Ittook three aspects to analyze tunneling. The first is single tunnel, it was not involves theimpact of surface building son tunnel; second，it was analyzed the effect of buildings and thedistance of tunnel center to surface on tunnel excavation；third，through the interactionbetween the twin tunnels was analyzed，simulated and analyzed the relationship andinfluence between side by side and knap sack mining methods of twin tunnels. Thedisplacement changes of oil in excavation process was analyzed， it had a positivesignificance in deep foundation design and to ensure the safety of construction.The theoretical models built were studied. It is concluded: in single tunnel excavationprocess, horizontal and vertical displacement increase with the increase of surfaceconstruction’s gravity, while strain range on the surrounding decreases; it can significantlyreduce the horizontal and vertical displacement with the tunnel center gradually away fromthe surface. It is of quite importance choosing the right depth in the actual excavation. In sideby side double tunneling process, it shows that vertical displacement decreases with thedistance between the two tunnel center increasing, while the horizontal displacement does notchange significantly, strain range decreases with the distance increase; in double tunnelexcavation process, it shows that horizontal and vertical displacement have no significantchange with the center distance of two tunnels increasing, and strain range decreases with thedistance increase. As for process of excavation, excavation is generally stable as a whole, themaximum deformation occurs at the top of the foundation pit. With depth increasing inexcavation, the total displacement shows a growing tendency in the process. When theexcavation reach pit bottom, the displacement rate of increase reduces, pit basically is stable.The study of tunnels and deep excavation is to find a minimal impact on the scope ofexcavation, which plays a significance role in actual working conditions.