Settlement behaviors of high-food-waste-content(HFWC) and low-food-waste-content(LFWC) municipal solid wastes(MSWs) respectively from developing and developed countries were characterized and compared based on a great...Settlement behaviors of high-food-waste-content(HFWC) and low-food-waste-content(LFWC) municipal solid wastes(MSWs) respectively from developing and developed countries were characterized and compared based on a great number of experimental datasets from references. Fresh HFWC-MSW generally has larger primary compression ratio compared to fresh LFWC-MSW, due to the release of a large amount of intra-particle water contained in food waste under additional stresses. The slopes of strain-logarithmic time curves with respect to the three secondary compression phases are characterized as "slightsteep-slight" for LFWC-MSWand "moderate-moderate-slight" for HFWC-MSW. It is difficult to distinguish the first two phases of the secondary compression in strain-logarithmic time curves for HFWC-MSW. The entropy method was built to evaluate the performance and applicability of nine published settlement models based on the settlement datasets of four large-scale experiments. The computational simplicity, the fitting performance, the prediction performance and the parametric stability were taken as the four criterions in the entropy method. Based on the evaluation results, the models proposed by Sowers et al.(1973)and Gourc et al.(2010) are recommended for predicting settlement at LFWC-MSW landfills, while the hyperbolic model and the Chen et al.(2010) model are recommended for HFWC-MSW landfills.展开更多
Municipal solid waste(MSW)is accumulating over elapsed time across the world,and it is observed in many projects associated with weak soils,such as marl.Therefore,effective solutions to the environmental problem are e...Municipal solid waste(MSW)is accumulating over elapsed time across the world,and it is observed in many projects associated with weak soils,such as marl.Therefore,effective solutions to the environmental problem are essential.Conventional techniques for stabilizing marl generally use substances such as lime and cement,which could exacerbate pollution.For this,some new stabilizers,e.g.nano-MgO,are used.There are large quantities of marls and MSW in Shiraz City,Iran.The present study aims to evaluate the feasibility of using nano-MgO as a green low-carbon binder to remove MSW from the environment and make construction projects more cost-effective.Consolidated drained shear tests were conducted to evaluate the mechanical behaviors of the nano-MgO treated marl specimens at high normal stresses.The marl specimens containing MSW percentages of 15%,25%,35%,and 45%and nano-MgO percentages of 0.25%,0.5%,0.75%,and 1%,were used.It is found that the marl containing 15%and 25%MSW and 0.5%nano-MgO at 28-d curing can perform cation exchange and form new cementitious products.The soils with merely MSW show good performance due to the removal of the kaolinite and the formation of brucite.However,the soil with 25%MSW and 0.5%nano-MgO shows the same strength enhancement as the specimen with the optimal nano-MgO(0.75%)through the formation of dolomite,with a 20.59%increase in strain energy(SE).展开更多
基金supported by the National Basic Research Program of China(Grant No.2012CB719802)the National Natural Science Foundation of China(Grant Nos.51708508,41402249)+1 种基金the Zhejiang Provincial Natural Science Foundation of China(Grant Nos.LY17E080021,LY15E080021)the Science Technology Department of Zhejiang Province(Grant No.2019C03107)
文摘Settlement behaviors of high-food-waste-content(HFWC) and low-food-waste-content(LFWC) municipal solid wastes(MSWs) respectively from developing and developed countries were characterized and compared based on a great number of experimental datasets from references. Fresh HFWC-MSW generally has larger primary compression ratio compared to fresh LFWC-MSW, due to the release of a large amount of intra-particle water contained in food waste under additional stresses. The slopes of strain-logarithmic time curves with respect to the three secondary compression phases are characterized as "slightsteep-slight" for LFWC-MSWand "moderate-moderate-slight" for HFWC-MSW. It is difficult to distinguish the first two phases of the secondary compression in strain-logarithmic time curves for HFWC-MSW. The entropy method was built to evaluate the performance and applicability of nine published settlement models based on the settlement datasets of four large-scale experiments. The computational simplicity, the fitting performance, the prediction performance and the parametric stability were taken as the four criterions in the entropy method. Based on the evaluation results, the models proposed by Sowers et al.(1973)and Gourc et al.(2010) are recommended for predicting settlement at LFWC-MSW landfills, while the hyperbolic model and the Chen et al.(2010) model are recommended for HFWC-MSW landfills.
文摘Municipal solid waste(MSW)is accumulating over elapsed time across the world,and it is observed in many projects associated with weak soils,such as marl.Therefore,effective solutions to the environmental problem are essential.Conventional techniques for stabilizing marl generally use substances such as lime and cement,which could exacerbate pollution.For this,some new stabilizers,e.g.nano-MgO,are used.There are large quantities of marls and MSW in Shiraz City,Iran.The present study aims to evaluate the feasibility of using nano-MgO as a green low-carbon binder to remove MSW from the environment and make construction projects more cost-effective.Consolidated drained shear tests were conducted to evaluate the mechanical behaviors of the nano-MgO treated marl specimens at high normal stresses.The marl specimens containing MSW percentages of 15%,25%,35%,and 45%and nano-MgO percentages of 0.25%,0.5%,0.75%,and 1%,were used.It is found that the marl containing 15%and 25%MSW and 0.5%nano-MgO at 28-d curing can perform cation exchange and form new cementitious products.The soils with merely MSW show good performance due to the removal of the kaolinite and the formation of brucite.However,the soil with 25%MSW and 0.5%nano-MgO shows the same strength enhancement as the specimen with the optimal nano-MgO(0.75%)through the formation of dolomite,with a 20.59%increase in strain energy(SE).