Triaxial Wetting Deformation Characteristics Of Unsaturated Laterite In Fujian Province

In the field of engineering construction,common laterite is used as filling material.Red soil as embankment or foundation backfill material has good stability,but in the case of continuous heavy rainfall or sudden rise of groundwater level,because of water saturation,there is the possibility of wetting deformation.Most of the researches on laterite focus on the strength and compaction characteristics,but the research on the wetting effect is low.so,it is necessary to investigate and study the wetting deformation of laterite.There are a large number of Taiwan funded enterprises in Fujian Coastal Development Zone,which adopt Taiwan standard(American Standard)in construction.One of the major obstacles for mainland technicians to be employed by Taiwan enterprises is the comparison of technical standards.In order to facilitate the docking of national standard and American Standard,the US standard was used to study the wetting effect of Fujian red soil.I hope to take this opportunity to strengthen cross-strait technical exchanges and cooperation.The unsaturated triaxial test was carried out to research the influence of different initial water content,initial dry density,saturation and plastic index on the wetting deformation of red soil in Fujian Province.The laws of wetting deformation of unsaturated red soil were summarized,and the experimental data of rainfall were enriched.The results of triaxial test and one-dimensional test were obtained The influence of the main stress ratio K and effective self weight stress on the wetting deformation of Fujian red soil is further revealed.The research results can be used as reference for geological environment investigation,geotechnical engineering investigation and geological disaster prevention and control in Fujian laterite and similar areas.The test results show that:(1)In the process of saturation,the curve of wetting deformation can be divided into three sections: suction stability,near saturation wetting deformation and saturation failure.(2)There is no wetting deformation in the suction range of 10 k Pa-200 k Pa for non plastic and plastic samples.(3)The specimens with high principal stress ratio have higher vertical wetting deformation than those with low principal stress ratio.(4)One dimensional wetting deformation test obviously underestimates the amount of wetting deformation.