Correlation Between Normalized Small Strain Shear Modulus and Shear Strength of Fiber-Induced MSW Fines

Abstract

The primary objective of this investigation is to assess the potential reusability of aged, dumped waste found in landfills for its application as a bulk geomaterial. Owing to the inherent heterogeneity of municipal solid waste (MSW), comprehensively understanding its behaviour—be it physical, mechanical, or dynamic—presents a significant challenge. Laboratory-based studies serve as a pivotal means to gain insight into a material's behaviour before its practical implementation. The study focuses on examining the intricate strength characteristics of MSW fines (< 4.75 mm) and fiber-reinforced MSW fines (with varying fiber content ranging from 0 to 10%) using the bender element laboratory test. The bender element analysis facilitates the determination of shear wave velocity (V_s) values by measuring the disparity in time travel between transmitted and received waves. Comprehensive scrutiny encompasses the influence of diverse parameters, notably the excitation frequency of the wave (f), applied confining pressure (σ_c), relative compaction (R_c), fiber content (FC), and the saturation state. Notably, the study identified an optimal fiber content of 1% across different excitation frequencies and applied confining pressures, where V_s or normalized G_max values exhibited higher levels. Furthermore, the study involved fitting a cubic polynomial model and devising a generalized equation that correlates the normalized small strain modulus with the normalized shear strength for fiber-reinforced MSW fines. This equation serves as a valuable tool in understanding and predicting the material behaviour concerning small strain modulus and shear strength in fiber-reinforced MSW fines.