Investigation expérimentale de l’effet de la taille des particules de verre concassé sur la réponse mécanique des sols granulaires

Abstract

The addition of materials such as recycled glass waste can have a paramount effect on the mechanical characteristics of soils. Specifically, in the field of geotechnical engineering, incorporating recycled glass waste into soils can enhance their mechanical and geotechnical properties, particularly their shear strength. This approach also presents environmental benefits by enabling the reuse of recycled glass waste that would otherwise be destined for landfills. In this context, this study proposes an experimental investigation into the influence of the particle size of recycled glass waste (Dmax= 4.00 mm, 2.00 mm, and 0.5 mm) on the mechanical response of granular soils. Additionally, an experimental protocol is implemented using the Casagrande shear box device to understand the behavior of this material and confirm potential correlations between the particle size of recycled glass waste and the maximum shear strength of granular soil samples, particularly Chlef sand mixed with various contents of recycled glass waste ranging from WRG=0% to WRG=30%. The samples are prepared in the laboratory using dry pluviation preparation technique and subjected to three initial normal stresses (σ = 100 kPa, 200 kPa, and 300 kPa) and a constant relative density (Dr = 90%). The results of the direct shear tests indicate that the particle size of recycled glass waste in terms of maximum diameter (Dmax) significantly controls the mechanical response of Chlef sand-recycled glass waste mixtures. Increasing the maximum diameter of recycled glass waste leads to a notable improvement in the maximum shear strength and friction angle, resulting in a significant increase in the dilatancy phase, for all fractions of recycled glass waste (WRG = 0%, 10%, 20%, and 30%) studied and the three selected levels of normal stress. Furthermore, It is found that recycled glass waste is a relevant parameter for enhancing the shear strength of sandy soils, where increasing their proportion results in a systematic improvement of the mechanical behavior.