Experimental Study Of Fiber And Lime Treated Collapsing Soil In Gannan Region

This paper takes the collapsing soil obtained from Yudu County,Ganzhou,Jiangxi Province as the research object,and the research based on a one-dimensional consolidation experiment indoor,considering different dry density,different water content,different lime content and additives on the compressive properties of collapsing soil,concluding that the soil dry density and lime addition on soil stress-strain curve has a significant effect,and the stress strain curve accords with hyperbolic model.Through the unconfined compressive strength test to studu the stress strain variation of soil samples with different dry density and different water content,and analys the effect of adding two kinds of materials,fiber or lime,as well as the mixture of fiber and lime on the unconfined compressive strength of soil.The results show that the dry density has a great influence on the axial stress,and the axial stress increases with the increase of dry density,the compression capacity of saturated soil is very small so in the rainfall condition,the collapse of the soil may cause landslides or collapse;Soil samples containing lime will suddenly break in damage when soil sample was immediately crushed,showing brittle failure,For the soil sample containing fiber,the soil sample will not break suddenly,will reach a stable state and stay for a period of time,showing ductile failure;According to the orthogonal test design the unconfined compressive strength test,for soil samples containing two mixtures of lime and fiber,the experimental results show that the optimum proportion is 6% of the lime content and the content of fiber is about0.2%.and lime is the main factor for the strength of the soil.The results of variance analysis showed that lime compared to fiber had a significant effect on the strength of soil.The CU and CD tests were carried out on soil samples containing lime and fiber to determine the effects of the two kinds of materials on the internal friction angle and cohesion of the soil and find out the optimal proportion of the two materials.The experimental results show that the optimal proportion is 8% limecontent and fiber content of 0.1%.Based on the data obtained from the above studies,build a model by Geostudio software in order to analyze the stability of the slope in the south of Jiangxi Province under the different conditions,The results showed that the optimum proportion of fiber was 0.2%,and the more lime content,the better the performance,the highest coefficient of stability of the mixed ratio of slope is 4% of lime and the soil of fiber 0.3%.