INDOOR FROST HEAVING EXPERIMENT OF SALINE SOIL IN DA'AN AREA, JILIN PROVINCE

There are plenty saline soil distributed in Da'an area, Jilin Province. Those soils show frost heave deformation due to the low temperature in winter, which can cause serious damage to construction projects and building structures. This paper takes field sampling collections of saline soil in Da'an area, Jilin Province. The physical and chemical property, soil grain composition of the soil samples are tested. The frost heave properties are studied using indoor frost heaving simulation experiment. The experiment results show that the salinization type of soil samples is carbonic acid type. Soil samples of research area have high exchangeable cation content and sodion content. The water content, salt content and compaction degree of soil samples all show imparity influence to the frost heaving results during frost heaving process. Frost heaving tests are carried out. The results show that with the temperature decreasing the frost heaving ratio increases. Only the frost heaving ration does not change much nearby the-10℃. For most of soil samples, with the compaction degree increasing the frost heaving ratio basically increases. The compaction degree affects frost heaving ration more obviously at low water contents soil samples. The soil samples of high salt content show lager frost heaving ratio than the low salt content samples. Besides, the frost heaving ratio take longer time to be stabilized than the low salt content samples. According to the test results, the largest frost heaving ratio is 3.5%. It ends up at soil samples with 26% water content, 1.5% salt content and 90%compaction degree. There is a best compaction degree of different salt content soil samples. The heaving ratio is increased by compaction degree of low salt content samples. But for high salt content samples, it shows inhibiting effect to soil if the compaction degree is too high or too low. For very low water content samples, high salt content shows inhibiting effect to soil samples. The soil samples show frost heaving only when the salt content is high enough. Soil has a frost heaving beginning water content, the frost heaving beginning water content of Da'an saline soil is 21%. This research provides theoretical basis to preventative mature of frost heaving damage in west Jilin Province.