Study On Cement Solidification Of Cadmium(Cd) Contaminated Soil Engineering Characteristics

With the accelerating process of industrialization, upgrading of industrial structure and adjustment of urban functional areas, a lot of industrial manufacturing companies closed down or relocated because they are at risk of contamination, which left a large number of industrial contaminated sites. Soil contamination by heavy metals is an important contamination type for this type of contaminated sites. Furthermore, after freezing and thawing of the nature of the presence of large areas of permafrost, soil certainly will change the conventional methods already NA. The study on consolidation of soil that polluted by heavy metals have become a hot spot and arouse widespread concerns from international environmental geotechnical engineering, geochemistry, environmental science and other disciplines in recent years. Study on solidification of soils that contaminated by heavy metals is significant in environmental protection, site restoration and utilization, and sustainable development of China.Based on this background, this paper rely on “Ministry of education scientific research foundation for the returned overseas Chinese scholars",the subject of the study is engineering mechanics property of cement solidification of soil contaminated by heavy metals cadmium(Cd). Through indoor sample preparation, with geotechnical test, freeze-thaw cycle test and synthetic analysis of testing data, the research aimed at discussing cement solidification of soil contaminated by heavy metal Cd,at room temperature, its change rule of unconfined compressive strength and anti-cut strength as different proportion of cement and heavy metals; at freeze-thaw temperature, its change rule of unconfined compressive strength and anti-cut strength as times of freeze-thaw cycles and temperatures of freeze and thaw; and the discussion on prediction of unconfined compressive strength of cement solidification of soil contaminated by heavy metal Cd in different times of freeze-thaw cycles and different proportion of cement. Main results are as follows:(1) At room temperature, as the proportion of cement increased, brittlement of test soil increases, unconfined compressive strength, anti-cut strength and cohesive strength increases, internal friction angle becomes bigger at the beginning and stable latter; as the proportion of heavy metal increased, plasticity of test soil increases, compressive strength, anti-cut strength and cohesive strength reduces, internal friction angle becomes bigger at the beginning and smaller latter.(2) As the freeze-thaw temperatures decrease, test soil’s stress-strain curve is to change, unconfined compressive strength, anti-cut strength and cohesive strength reduces, internal friction angle becomes bigger; the extent of variation of freezing and thawing is big at first time.(3) With the increasing times of freezing and thawing, test soil’s strain curve is to change, unconfined compressive strength reduces,changes of anti-cut strength cohesive strength, and internal friction angle are closely related to proportion of heavy metals, and it tends to be stable after freezing and thawing for 6 times.(4) This paper systematically reviewed and summarized the achievements made by domestic and foreign scholars in the fields of prediction oil solidification, solidification of heavy mental contaminated soil.(5) Based on other scholars’ prediction of strength of cement solidification of heavy mental contaminated soil, and combined with experimental data through reasonable data fitting, it puts forward predicting model of cement solidification of Cd contaminated soil, and validates through data.