Influence Of Groundwater On Design Scheme Of Deep Foundation Pit Support Engineering

With the development of national economy,land of urban is becoming more and more tense,and buildings of city become more and more dense.Demand of foundation pit is more higher,the existence of groundwater make foundation pit engineering construction difficulty greatly increases,that can be found by studying the engineering example,most of the foundation pit instability are closely related to the groundwater,such as not to deal with problems of groundwater,that will be the phenomenon such as in quicksand,piping,tu chung.Traditional way for dealing with the groundwater is the foundation pit precipitation,precipitation of foundation pit is to continue extracting groundwater during construction in the process,the pumping Wells pumping formation of precipitation funnel,radius of precipitation influence is big,generally between a few hundred meters to thousands meters.Within its radius of influence,because the underground water level drops,cause the consolidation settlement of soil,caused by light overlay produces micro tilt,or cause the surrounding roads collapse,pipeline rupture,the building wall cracking and even failure.Foundation pit precipitation in most directly make the groundwater directly discharged into municipal network,not only led to drainage municipal pipe network pressure,also caused the countries pay a large amount of sewage disposal,and caused a lot of the waste water.In recent years,the government and other departments to attaches great importance to the problem of foundation pit precipitation,related policy,limit of foundation pit precipitation,emphasis on green construction of foundation pit,the construction of the whole process to conform to the water,land,material saving,energy saving etc.As to research in hydraulics and soil mechanics,foundation pit design principle as the foundation,from the groundwater seepage,the interaction of water and soil,the region and the most common ways of supporting conditions of use and other aspects,to explore the foundation pit of water stop measures of groundwater,and form a complete set of supporting design scheme,the groundwater seepage theory is used to calculate water stop curtain of waterproof performance,using the finite element software MIDAS/GTS NX to simulate analysis the design that was carried out on,according to a certain foundation pit project actual site conditions,hydrological conditions,engineering geological conditions,the whole process simulation in this scheme,the force and displacement of supporting structure changes.Through theoretical analysis,software simulation and analysis of project instances,this paper provides a feasible support design scheme for the treatment of ground water in this area,it changed the design and construction cost of water stop curtain to increase several times.It is hoped that we can provide some experience for the design of non-precipitation support in this area.