Effect of geomembrane liner on landfill stability under long-term loading: interfacial shear test and numerical simulation

• Published in: Environmental science and pollution research international 2024-04, Vol.31 (18), p.27345-27355
• Main Authors: Xia, Xiong, Pan, Ziqing, Qiu, Hongyong, Xie, Xiankun, Guo, Kai
• Format: Article
• Language: English
• Subjects: Age; Aquatic Pollution; Atmospheric Protection/Air Quality Control/Air Pollution; Clay; Clay - chemistry; Clay liners; Computer simulation; Earth and Environmental Science; Ecotoxicology; Environment; Environmental Chemistry; Environmental degradation; Environmental Health; Excavation; Feasibility studies; Finite element method; High density polyethylenes; Interface stability; Interfacial shear strength; Internal friction; Landfill; Landfills; Mathematical models; Municipal solid waste; Municipal waste management; Polyethylene - chemistry; Refuse Disposal; Research Article; Safety factors; Shear Strength; Shear tests; Solid Waste; Solid waste management; Solid wastes; Waste Disposal Facilities; Waste disposal sites; Waste Water Technology; Water Management; Water Pollution Control
• ISSN: 1614-7499; 0944-1344; 1614-7499
• DOI: 10.1007/s11356-024-32953-3

Clay liners have been widely used in landfill engineering. However, large-scale clay excavation causes secondary environmental damage. This study investigates the feasibility of replacing clay liners with high-density polyethylene (HDPE) geomembranes with different specifications and parameters. Laboratory interface shear tests between municipal solid waste (MSW) samples of different ages and geomembranes were conducted to study the influence of landfill age on interface shear strength. Finite element method was adopted to compare the long-term stability of landfills with HDPE geomembrane versus clay as intermediate liner. The interfacial shear test results show that the cohesion of MSW increases in a short term and then decreases with landfill age. The internal friction angle exhibits an increasing trend with advancing age, however, the rate of its increment declines with age. The rough accuracy of the film surface can increase the interfacial shear strength between MSW. The simulation results show that, unlike clay-lined landfills, the sliding surface of geomembrane-lined landfills is discontinuous at the lining interface, which can delay the penetration of slip surfaces and block the formation of slip zone in the landfill. In addition, the maximum displacement of landfills with geomembrane is 10% lower than that with clay, and the absolute displacement of slope toe decreases with the increase of roughness at the interface of geomembrane. Compared with clay-lined landfills, the overall stability safety factor increased by 18.5–30%. This study provides references for landfill design and on-site stability evaluation, contributing to enhanced long-term stability.