Slope stability of municipal solid waste landfills under combined effects of gas pressure and temperature changes
SHU Shi1,2, SHI Jian-yong1,2
1. Key Laboratory of Ministry of Education for Geomechanics and Embankment Engineering, Hohai University, Nanjing 210024, China; 2. Geotechnical Engineering Research Institute, Hohai University, Nanjing 210024, China
Abstract：Engineering accidents of slope failure in municipal solid waste (MSW) landfills under the high leachate level have occurred many times. The preliminary analysis indicates that the slope failure is caused by various factors such as leachate level, gas production and temperature increase caused by the waste degradation. However, very limited researches have been conducted to analyze slope stability of landfills considering the combined effects of leachate level, gas pressure and temperature. In this study, by simplifying the calculation of gas pressure and temperature distribution of landfills, the Sweden slice method is used to analyze the slope stability of landfills under the combined effects of leachate level, gas pressure and temperature. The calculated results show that considering the influences of gas pressure and temperature, the safety factor of slope stability of landfills is reduced by 24.7%~43.0%. When analyzing the slope stability considering the combined effects of leachate level, gas pressure and temperature, it is recommended to control the minimum safety factor to be greater than 1.0 to ensure the safe operation of landfills. This study can provide theoretical support for the design, construction and operation management of MSW landfills.
舒实, 施建勇. 气压和温度变化共同作用下垃圾填埋场边坡稳定性研究[J]. 岩土工程学报, 2022, 44(1): 82-89.
SHU Shi, SHI Jian-yong. Slope stability of municipal solid waste landfills under combined effects of gas pressure and temperature changes. Chinese J. Geot. Eng., 2022, 44(1): 82-89.
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