Study On The Mechanical Properties Of Clay-solidified Grouting Cemented Complex

At present, abandoned mine used as landfill place not only solves the ecological restoration problem of abandoned mine, but also provides new way of landfill site selection in order to relieve land resources scarcity brought by landfill construction. The mine landfill high-steep slope stability is the key problems urgently to be solved in the process of landfill construction and operation. According to high-steep slope stability problem, using clay hardening steps in landfill bare slope plays a protection role for slope body stability in combination with the clay-solidified grouting technology. Therefore, the study on the mechanical properties of clay-solidified grouting cemented complex has important significance for the design of compactibility steps and evaluation of high-steep slope stability. The research of landfill high-steep slope grouting technology centralizes on the seepage effect currently, but there are less research on the strengthen effect of the clay grouting technology. Therefore, combined with Changshankou landfill engineering situation, laboratory test on the mechanical properties of clay-solidified grouting cemented complex and the numerical simulation of landfill slope under the condition of loading and rainfall are developed in this paper. The main research results are as follows:(1) By the mechanical properties of clay-solidified grouting cemented complex load-strain test, the load-time curve and strain-time curve can be obtained. The curves show that cemented complex strain change under the different load. The result can supply reliable data for the research on the cemented complex stress-strain properties.(2) According to three influencing factors of cemented complex compressive strength, the compressive strength impact factor test result show that the influence of the different factors. The result can provide liable basis for the design of landfill slope and compactibility steps.(3) The bond surface roughness have influential action on cemented complex flexural strength, it is proved by the single factor test. By this test, the fitting formula with bond surface roughness influence factors for cemented complex flexural strength is obtained. The result can direct the slope rough surface treatment method using compactibility steps.(4) Based on the theory of damage mechanics and material mechanics, considering the characteristics of clay solidified grouting cemented complex bond surface, the numerical model is established to analyze the difference of numerical and test results. The results verify the feasibility of bond damage model using in the numerical calculation and supply the support of the numerical calculation accuracy.(5) Based on the theory of geotechnical mechanics and damage mechanics, this paper build the stress and strain model to analyze the deformation of the landfill slope under the different load. The results show that the deformation of landfill, clay hardening steps and bond surface, and offer liable basis for the design of landfill amount per a day and thickness design.(6) According to the unsaturated soil mechanics and fluid mechanics, the landfill slope stability fluid-solid coupling numerical model under the condition of rainfall for both bare slope and compactibility steps slope is set up in combined with minimum safety factor equation. The results show that compactibility steps can effectively reduce the possibility of slope landslide and can offer the available slope strengthening ways.The results can provide theoretical foundation of the feasibility of clay compactibility steps implementation and afford technical support for landfill stability study and landfill design. The results have significant guiding significance and application value.