Effect of Apparent Cohesion on Translational Failure Analyses of Landfills

The scope of this paper is to develop a new analysis method introducing the effect of apparent cohesion of the waste and/or liner materials on the translational failure of landfills. The apparent cohesion of the liner materials seriously affects the factor of safety (FS), especially for a liner interface with a low friction angle and high apparent cohesion. Obtaining accurate and reliable apparent cohesion for various liner materials becomes an important approach for translational failure analysis. The relationship between B and ${\mathrm{FS}}_{\mathrm{ave}}$ for $c>0$ is different with that for $c=0\text{.}$ Using an equivalent friction angle to represent the apparent cohesion of the liner materials may lead to an unsafe result. Also, a waste filling sequence, to keep the FS above a stipulated value during the landfilling process, can be generated. The values of ${\mathrm{FS}}_V/{\mathrm{FS}}_{\mathrm{ave}}$ varies between 1.9 and 2.1 and are concentrated around 2.0 when ${\mathrm{FS}}_{\mathrm{ave}}⩾0.95\text{.}$ The approximate solutions of FS with adequate accuracy can be obtained by assuming ${\mathrm{FS}}_V=2.0\cdot \mathrm{FS}$ when FS⩾0.95.