Study On Unsaturated Characteristics Of Improved Expansive Soils In Hefei

During the current construction in China is in rapid growth,many construction and major projects are being prepared.In the construction of our country’s engineering construction in full swing,expansive soils is a problem often encountered in the project engineering.This expansive soils of Hefei research is to study the properties of unsaturated,unsaturated soil and the main difference between saturated soil from the Matric suction,unsaturated soil suction is covered in significant contributions to,the change will cause the moisture in soil of different suction and will lead to changes in slope of soil strength.Thus,studying the relationship between moisture content and matric suction,and on the strength of unsaturated soil is extremely meaningful research topic.First of all,based on the accumulated knowledge of unsaturated soil mechanics,experimental study on basic mechanical properties of expansive soils in Hefei.Hefei expansive soil of the unconsolidated-undrained Triaxial tests and boundary water content tests and free expansion rate and filter paper test.On the basis of the test results,and have a basic understanding of Hefei expansive soil properties for further research based on improved swelling soil in Hefei.Second,paper focus for has different mixed than of lime and the building muck improved Hefei expansion soil of filter paper method test,from soil water features curve of defined began wrote up,has been to predecessors analysis of soil water features curve of model analysis,later on paper of lime and the building muck in different mixed volume Xia of soil water features curve for analysis,from power function intends collection to transform coordinates of once function intends collection,then on once function parameter for compared analysis.Finally,this paper use a intake ceramic plate of unsaturated direct shear apparatus,of Hefei expansive soil by lime improvement and construction waste unsaturated tests.Study of Hefei expansive soil under different suction control strength variation,net normal stress-suction-three-dimensional envelope surface shear stress.And then discuss the improved relationship between suction and strength of expansive soil of Hefei.In papers conclusion aspects according to need according to different of workers condition selection different of processing approach:(1)6% mixed volume of improved soil sample on Hefei expansion soil of expansion sex has is good of inhibit effect;in building muck improved test in the,with building muck of mixed volume increased,Hefei expansion soil of expansion sex gradually declined,therefore in simple consider expansion sex of engineering application in the,can more mixed added building muck;(2)soil water features test research in the,4% lime mixed volume of coefficient is a mutation points,in building muck by 10% to 12% Again to 15% of process among,matrix suction of intends collection curve cut from and slope are is rendering first reduced again increases of trend,this papers test ratio in the building muck of cut from obviously is greater than mixed added lime of improved Hefei expansion soil and slope obviously is less than lime improved Hefei expansion soil;(3)through axis translation technology of non-saturated straight cut test get has Hefei expansion soil in 50-450 kPa matrix suction within of strength damage package complex surface analysis get mixed added 12% Construction waste,construction waste improving expansive soil of Hefei Hefei expansive soil in pilot ideal dosage...