垃圾填埋场沿底部衬垫系统破坏的稳定性分析

为研究垃圾填埋场沿底部衬垫系统破坏的稳定性,将填埋场分为主动楔体、被动楔体和垃圾坝三部分。对它们进行极限平衡分析,建立平衡方程,求解填埋场的稳定安全系数。考虑条间力的变化,可以计算填埋场的最大、最小安全系数Fmax和Fmin,采用平均安全系数Fave来代替真实安全系数Ftrue,研究发现,Fave和Ftrue的最大相对误差不超过5%。Fmax随着城市固体废弃物内摩擦角φsw的增加逐渐增大,而Fmin随着内摩擦角φsw的增大并不改变;Fmax、Fmin和Fave都随着垃圾坝高度H2和底部摩擦角δDA的增加逐渐增大,垃圾坝对填埋场的稳定性有较大影响。

Analysis on translational failure of landfill along the underlying liner system

A limit equilibrium analysis was used to calculate the factor of safety for the waste mass against possible translational failure along the underlying liner system.The landfill could be divided into three parts: an active wedge lying on the back slope that tended to cause failure,a passive wedge and retaining wall resting on the foundation or liner system that helped to resist movement.With the change of interwedge forces,the upper and lower bound solutions for the landfill stability,i.e.,Fmax and Fmin,could be readily determined using this method.The average factor of safety Fave was used in this paper,instead of the true factor Ftrue.It was shown that the differences between Fave and Ftrue were within 5% for all cases.Fmax increased with the increasing of internal friction angle of municipal solid waste φsw,however,Fmin remained constant.All the factors of safety Fmax,Fmin and Fave increased with the increasing of height of retaining wall H2 and the friction angle between the retaining wall and the liner system δDA.It was found that the retaining wall significantly affected the stability of landfill.