A Review of Geotechnical and Adsorption Properties of the Soils Modified with Geopolymer:A Promising Landfill Barrier Material

Abstract

In the structure of a landfill site, it is necessary to set up a top cover and a bottom liner layer, usually using materials such as compacted clay, geomembrane and geosynthetic clay.In the past few decades, an increasing number of new materials have been proposed as alternative materials for landfill barriers.Geopolymers, as a relatively new material, have sufficient mechanical strength, low CO2 emissions, and high adsorption capacity, which may make them candidate materials for landfill barriers.This paper provides a detailed and critical review of the geotechnical properties (compressive strength, permeability) of geopolymer modified soil and its ability to adsorb heavy metals, exploring the effects and influencing factors of geopolymer modified soil.Overall, the strength and permeability of geopolymer modified soil meet the requirements of landfill barriers, and it has good adsorption capacity for heavy metals, which makes them promising as barrier materials for landfill sites to compensate for the scarcity of local clay resources.This review can provide reference for the selection of landfill barrier materials and the evaluation of the long-term safe use of landfill barrier layers.

Keywords: Landfill barrier, Geopolymers, Compressive Strength, Permeability performance, Adsorption of heavy metals