Heavy Metal And Geotechnical-Chemical-Mechanical Coupling Effect In Coal Gangue Adsorbed By Expansive Soil

Coal gangue is a solid waste that contains trace heavy metal elements.With China's energy-saving emission reduction,resource recycling and other policies,coal gangue has been widely used as a roadbed filler material,the surrounding soil and water pollution caused by the environment caused by secondary pollution,so the coal gangue trace heavy metal elements must Strengthen research and prevention.Expansive soil is engineering waste,but with adsorption.The use of this feature,can reduce the pollution of coal gangue on the surrounding environment.The coal gangue in Dongsheng and Wuhai of Inner Mongolia were selected into different expansive soils,respectively,and the proportion of soil was 0%,10%,20%,30%,40%.The samples were subjected to static leaching and dynamic leaching tests with different pH value and different temperature solutions.Zn,Ni,Cd,Cr,Pb were tested for the concentration of heavy metals in the leaching solution.The unconfined compressive strength test was carried out.And the leaching law and the unconfined compressive strength values are coupled with each other.Test results Surface:After leaching,the incorporation of different proportions of expansive soils has different effects on pH value,spectrophotometric value and precipitation of heavy metal concentration in coal gangue.The compressive strength of the mixed expansive soil is higher than that of the unmixed soil.The compressive strength of the sample is higher when the acid and alkaline solution are leached.The pH value and trace heavy metal concentration after leaching were consistent with the unconfined compressive strength.At the same time,the total amount of heavy metal leaching accumulation and the amount of soil into a parabolic relationship.When the amount of soil is 20%,the compressive strength is the highest and the concentration of accumulated heavy metal is the smallest.