The Deformation Research On Supporting Structure In Deep Excavation

As a major engineering hot issues of today’s urban development, deep excavation has received increasing attention from the design and construction workers.In the trends from the deep excavation,from the initial strength control developed to the deformation control,environmental geotechnical problems can be seen in the deep foundation has become more important.In this paper,the deep excavation engineering of Xun Li-men station in Wu Han metro Line 2 is the background sample,mainly study and analyze the excavation deformation rule,including as following:(1) During the construction stage,the monitoring of the horizontal displacement of the underground diaphragm wall and soil behind the wall,the monitoring of reinforcement stress have been completed.Selected part of the actual data of the monitoring project were compared and analyzed,including the effect from different construction stages, different forms of internal support on the wall deformation and displacement of soil behind the wall.Discussing the displacement trends and the final shape of displacement of the underground diaphragm wall in different excavation depths, conclusion is drawn that the horizontal displacement of diaphragm wall increases with the excavation depth increasing,the shape of the wall deformation above the basement wall main was "shear" type(not true so-called shear deformation,its position of maximum horizontal displacement is not at top of the wall,which position at about 5m below the top of the wall,but the shape is close to the shear deformation curve).The shape of the deformatiom was inverted "S" type,above the basement,the wall move to the inside of excavation,below the basement to the outside. (2)By the finite element method simulation software,the excavation process was simulated,the calculated and constrction data were compared,the complicating constrction factors are not fully reflected in the model,so there is a large difference between calculated and actual results,but the simulation result have some reference supporting role.(3)Simulate 4 different model which have different construction parameters, through comparison between models,summed up the wall deformation characteristics with the support in different lengths and different soil properties.