Experimental study on the cyclic behavior of silty sands reinforced by disposal of shredded facemask

Abstract

Due to the COVID-19 pandemic, personal protective waste generation has increased worldwide. Given this problem,urgent waste management methods are required to reduce waste surcharge to the environment. The present study tries to clarify the question using particle-level modeling combined with 36 undrained cyclic triaxial shear tests. The physical properties of the base materials and the face mask (FM) are first investigated and scanning electron microscopy is used to image the soil particles.This study used two kinds of sand with different median grain (D50) sizes.In doing so, shredded face mask (FM) contenthas been modifiedfrom 0 % to 1 %. In a Small silt system (fine content ≤ 40 %), liquefaction resistance decreased with silt content addition and had an opposite behavior in a Large silt system (fine content ≥ 40 %) for both sands. FM addition to silty samples leads to sustainable improvements such as more dilatative behavior and dissipation of excess pore water pressure, and enhanced liquefaction resistance. The effectiveness of FM reinforcement diminished with increasing the median grain size (D50). Also, the shear modulus of clean and silty sands improved with FM addition.