The deformation characteristics of modified lightweight expanded polystyrene soils under cyclical loading

Abstract

A dynamic triaxial test was conducted to assess the deformation characteristics of sodium silicate modified EPS (expanded polystyrene) particle lightweight soil (SCS) under cyclical loading. The hysteresis curves, dynamic elastic modulus, damping ratio, and cumulative strain were obtained for SCS samples with varying EPS particle content. We found that the samples' stress-strain hysteresis curves, became crescent-shaped for different dynamic stress situations, and were largely elastic in the latter phases. Furthermore, there was a progression from dense to sparse as EPS content increased. With increasing dynamic stress, the dynamic elastic modulus and damping ratio of SCS also rose. The damping ratio of SCS rose as the EPS particle content increased, whereas the dynamic elastic modulus decreased. Notably, increases in the PS particle content and dynamic stress largen the deformation of the SCS samples. Moreover, we found that when the cumulative strain curve becomes stable, varying the contents of EPS particles under different dynamic stresses leads to a power function relationship with the logarithm of the number of cyclic loading cycles. In cases where the cumulative strain curve reaches a critical or destruction point, the cumulative damage variable displays a power function relationship with the vibration count.