Experimental Study On Pile-Sheet Retaining Wall And Flexible Retaining Wall Applied In Yun Gui Railway

Engineering Diseases of Expansion Soil has always been a worldwide technical problem at home and aboard,which has always been a engineering "cancer",that has not been properly resolved.It will be swelling,softening,disintegration when it meets the water and it will be shrinkage,cracking when it is discharged,it will have a serious impact on the stability of the expansive soil embankment,cutting and the structures.China is the one of most widely distributed by the expansive soils.and the one of countries which is most seriously affected by the expansive soils disasters.Guangxi,Yunnan province are the most serious hazards areas by the expansive soils disasters in China (rock),especially in the Baize area,where expansive soils features are extremely complex. So it will damage the cutting slope.At present, there are many researches about expansive soil slope.but most of them did not consider the influence of swelling force on slope stability.And also,there is no uniform perspective on the expansive soil slope failure mechanism,supporting structure design and calculation.In order to overcome these above Problems,we base on project supported by railway ministry:"Research on the key technology of Yun Gui Railway",through the indoor data research,field invest,field test,field monitor,theoretical analysis and numerical simulate,we study expansion force,rigid,flexible retaining effect from experimental and theoretical.The main content of the research are as follows:(1) Site survey was conducted on railway and road In a typical expansive soil area.Research content mainly includes the area condition of the swelling soil area、typical physical and mechanical properties of expansive soil、cutting embankment failure form of slope,slope and retaining structure supporting forms and its effect and so on.(2) Carries out expansion force test in situ,we select two test section in situ test in the strong expansion of land area and the weak expansive soil area, using the definition of the expansion force.Under the rainfall conditions,using of the loading system completely limit the expansive soil swelling deformation to test expansive force.(3) Burying earth pressure cell,concrete strain gauges,humidity sensors and other test components in sheet-pile retaining system,under the rainfall condition,test the Influence of the swelling force on the pile and pile board,and test pile wall supporting effect.(4) Burying earth pressure cell,the flexible displacement meter and humidity sensors in geo-grid reinforced earth retaining wall,under the rainfall condition,Testing of vertical stress changes,tensile force changes, soil moisture changes of geo-grid reinforced earth retaining wall.The calculated results of the practical project.Test of geo-grid reinforced soil retaining wall actual effect of reinforcement.(5) Through carries on the numerical simulate of geo-grid reinforced soil retaining wall,considering influence of expansive force, weak layers,reinforced on slope stability.