Experimental Study On GCL Application Characteristic Under Complicated Condition

In recent years,more and more municipal solid waste had been dumped into the landfills.In order to prevent the landfill leachate from contaminating soil and groundwater,anti-seepage work is the key.GCL(Geosynthetic Clay Liner)as the new anti-seepage compound earthwork material,because of its light weight,small thickness,the construction is simple,strong ability of self-healing superiority and low permeability.It has been widely used in landfill,canals,lakes and other fields of liner system.Now some scholars of GCL and bentonite adsorption performance,physical and mechanical properties,and permeability had a more in-depth study,but the conditions for the existence of heavy metal ions of study is less,and this kind of condition in engineering,and gradually become the important factors influencing the technology selection.On the other hand,the existing method of metal in the soil testing process too complicated,need to contact the sample,it is difficult to achieve the result of nondestructive,need to seek a rapid,non-destructive,in situ detection method to detect the metal ion content of soil.In this paper,laser induced breakdown spectroscopy detection technology was introduced to analyze the generated plasma spectra by high power pulsed laser,and obtained the metal elements in the soil,which is convenient and efficient and meets the aforementioned requirements:(1)In order to test lead ions adsorption ability of bentonite,this article discusses the reaction time,reaction temperature,reaction velocity,ion concentration,dosage of bentonite,and the influence of pH on the adsorption properties;(2)The multi-link flexible wall permeameter was developed for the penetration test,and the same batch of GCL can be test simultaneously with the same conditions.It can avoid the errors caused by the samples and test conditions,and improving the reliability of the data;(3)Under different GCL hydration conditions,the greater concentration of hydrating liquid,the more stable the permeability coefficient,the more stable.the permeability coefficient,and the integrated analysis of the permeation process;(4)The penetration performance of GCL under different apertures was tested with the self-made permeameter,and the factors affecting its self-healing capacity were briefly analyzed;(5)Through the laser induced breakdown spectrum test,the metal elements in the surrounding soil are quantitatively detected by GCL and real-time monitoring of the content of metal elements in soil can be realized.