Experimental Study On Soil Physical Properties And Curing Mechanism Of Heavy Metal

Aiming at the problems such as high porosity ratio,high compressibility,low shear strength and poor carrying capacity of heavy metal contaminated soil led to low strength of the foundation,large deformation and uneven settlement and other issues,In this paper,heavy metal(Pb²⁺、Zn²⁺、Cu²⁺)contaminated soil were selected as the research object.Firstly,we analyze the chemical composition and microstructure of sampled soils,and then explore the effect of heavy metal ion species and its concentration on the physical and chemical properties of contaminated soil.Using indoor test,a variety of test techniques and related mathematical methods,and study the heavy metal contaminated soil curing mechanism.The effects of various physical and chemical properties,mineral composition,microstructure,heavy metal ion concentration,curing agent and its dosage and age on the curing effect of heavy metal contaminated soil were analyzed comprehensively.Establishment and development of curing mechanism of heavy metal contaminated soil considering the interaction of "soil-curing agent-heavy metal ion" has given the effects of curing agent and its content（ratio）,heavy metal ions（concentration and composition）,soil strength,leaching and permeability on the curing process and its relationship,which provides theoretical and technical support forthe development and reuse of heavy metal contaminated sites.Themain research contents are as follows:（1）Study on the physical and chemical properties of heavy metal(Pb²⁺、Zn²⁺、Cu²⁺)contaminated soil.First,the soil samples（contaminated soil and non-polluted soil）were taken as the research object to study the physical and chemical properties of heavy metal contaminated soil before and after the pollution,the effect of heavy metal ions and the influence of each factor.Then,the physical and chemical properties of heavy metal contaminated soils and non-contaminated soils,the effects of heavy metal ions and the correlations of their influencing factors were studied.Finally,the research results of field sampling and laboratory preparation are compared,and the rationality of indoor simulation test is discussed,and the correlation between the two research results is analyzed.（2）Study on curing mechanism of heavy metal(Pb²⁺、Zn²⁺、Cu²⁺)contaminated soilThe effect of "soil-curing agent-heavy metal ion" on the microstructure of heavy metal contaminatedsoil during the curing process was discussed.（3）Study on Curing Technology of Heavy Metal(Pb²⁺、Zn²⁺、Cu²⁺)Contaminated SoilThe contaminated soils(Pb²⁺、Zn²⁺、Cu²⁺)were studied by means of indoor simulation test.The selection and application of curing agent and additives and their contents（mixing ratio）were discussed when the heavy metal contaminated soil was treated with different pollution levels-and condition.