Centrifuge shaking table test studies on mechanically biologically treated waste

The dynamic properties of mechanically biologically treatment (MBT) waste are vital for the seismic design of landfills. This study employs a centrifuge shaking table to experimentally investigate the behaviour of MBT waste using sinusoidal and Taft waves. The results reveal the following key findings: (1) MBT waste exhibits a certain degree of dilatancy under low confining pressure. (2) The natural frequency range of MBT waste is determined to be 1-7 Hz, with pronounced resonance effects observed at frequencies of 1.506, 2.97, 4.028 and 6.226 Hz. (3) The dynamic amplification factor decreases with increasing peak ground acceleration (PGA), ranging from 1.024 to 1.506. (4) For the same waveform, the equivalent shear modulus decreases with higher PGA, while for identical PGA, the equivalent shear modulus is greater under Taft wave than sinusoidal waves. (5) The excess pore water pressure (EPWP) ratio declines with increasing burial depth, and liquefaction does not occur at any of the monitoring locations. (6) The EPWP ratio increases with strain, and an empirical relationship between the EPWP ratio and shear strain is proposed. (7) A comparative analysis is conducted between the EPWP ratio of MBT waste under shear strain, and the experimental results reported in previous studies. These findings provide a valuable reference for the dynamic-stability analysis of MBT waste landfills.