The Research On The Impact Of Water In The Subgrade And The Protective Measures

In many parts of our country and the world are humid and wet areas,in where there isabundant rainfall but little sunshine.There are many problems to build earth materialembankment engineering just as highways,railways,dams,etc.in these areas,especiallyunusually wet areas.By the impact of rain in the subgrade,higher and wider-range moisturecontent of the fillers may cause large and differential settlement.In addition,the subgrade issusceptible to develop frost heaving damage,and subgrade bearing capacity becomes smaller.With regard to the test of subgrade-filler moisture content rangement and the influence test ofearth material physical and mechanical properties by water,this paper proposed protectionmeasures and methods to subgrade.The following specific work was undertaken.a)Problems on highway construction and operation in rainy wet areas wereanalyzed,moreover,related research materials were arranged and evaluated.Under theseworking,the carried-out research contents of this study and adopted technical line wereproposed.b)By the field test of moisture content of the subgrade fillers,the influencing factors ofthe dimension and diversification had been analyzed.c)Under different overburden pressure with different initial moisture content and initialdry density of soil samples,we did the water immersed compression test and studied the testresults.The variation of deformation stability time and soil material density, water content hadgot.Relevant recommendations of subgrade construction and protection had also beenproposed.d)Through the test of the relationship between the soil material in differentdensity,moisture content and unconfined compressive strength,we got the law of soil materialstrength,elastic modulus with the change of moisture content, density and air volume change.e)In order to prevent the adverse effects of rain on the roadbed filling in foundationconstruction process and completion of subgrade construction,this paper proposed protectionmeasures and methods to subgrade.