Study On Improvement Of High Liquid Limit Soil In Yangxi-mata Section Of Shenzhen-maoming Railway

In this paper,because that the high liquid-limit soil is widely distributed over the YANGXI-MATA zone of Shenzhen to Maoming Railway,by means of the site survey,the laboratory test,and compaction process test,the lime improves high fluid soil is studied systematically as the railway subgrade material.Through site survey,the laboratory test,the regional characteristic of the high liquid-limit soil distributed over the YANGXI-MATA zone is studied.Because the fines content?natural moisture content,the liquid-limit and plasticity index of the tested soil is high,the high liquid-limit soil has such poor engineering properties as high compressibility,low permeability,low strength and high variability in physical properties.Meanwhile,High liquid limit soil has characteristics such as many kinds,soil quality uneven,significant variation in coarse particle content,insignificant expansion and shrinkage.After the result of the drying method and method of mixed with stone sand to improve high liquid limit soil can not meet the requirements of subgrade filling,the laboratory test is carried out to study the feasibility of lime stabilized high liquid-limit soil.The Liquid plastic limit test and the compaction test of representative soil samples showed that adding 5% lime can improve the liquid plastic limit and compaction performance of the mixed soil.The unconfined strength of the lime stabilized soil with a high liquid limit can meet the requirements of roadbed design specification for improved soil packingTest of filling process were carried out under 3% and 5% two kinds of lime proportion.By test results,the influence of process parameters is analyzed,including rate of adding in lime,rolling way,moisture content,and paving thickness.The Filling process parameters of the lime stabilized soil with high liquid limit is as follows: the ratio of lime proportion is 5%,moisture content is 21%,the paving thickness is 45 cm,the rolling way is 1-static compaction+7-dynamic compaction+1-static compaction.The results of this paper can be used as reference in similar projects.