【摘要】 将组分及物理指标一致的自制垃圾在适宜条件下进行加速降解,分别采用大尺寸三轴渗透试验和常水头渗透试验测试不同降解龄期自制垃圾在不同应力条件下的饱和渗透系数,对试验结果进行比较分析.研究孔隙比、降解龄期、有效应力、测试方法等因素对垃圾渗透性的影响,与成都、苏州填埋场现场取样测得的垃圾三轴渗透系数进行对比.试验结果表明,填埋体的压实和埋深对饱和渗透系数的影响较大,渗透系数的对数随孔隙比线性增长,渗透系数的倒数与有效应力线性相关.在相同孔隙比的前提下,渗透系数随降解龄期略有减小.采用不同测试方法对渗透试验结果的影响显著,三轴渗透试验的渗透性结果明显低于常水头试验结果.自制降解垃圾的三轴渗透性与现场取样的试验结果相符,能够用于实际工程的设计和评估.更多还原

【Abstract】 Artificial wastes with the same composition and physical index degraded in a large self-developed degradation instrument under optimal conditions.Triaxial permeability tests and conventional permeability tests were conducted to measure hydraulic conductivity of waste under different stress conditions during different degradation stages.The influence of the void ratio,degradation age,effective stress and test method on the hydraulic conductivity was investigated.The hydraulic conductivity of samples drilled from Chengdu and Suzhou landfill were measured by triaxial permeameter and the results were compared with those of artificial wastes.Results demonstrated that the saturated hydraulic conductivity of MSW was significantly reduced with the increase of the effective stress or the decrease of void ratio.The logarithm of hydraulic conductivity was approximately linear with the void ratio or the reciprocal of the effective stress.For wastes of the same void ratio,hydraulic conductivity was insignificantly reduced with the increase of degradation age.Testing methods had a substantial impact on the permeability of wastes,and the result from triaxial permeability test was lower than that from conventional permeability test.The hydraulic conductivity of artificial samples matched that of filed samples,and the results can be applied to the practical engineering design and evaluation.更多还原