Liquid-gas responses during rainfall test in MSW landfill

Area of Science:

• Environmental Engineering
• Geotechnical Engineering
• Hydrogeology

Background:

• Rainfall infiltration into landfills is common.
• Liquid-gas interactions within waste are complex and affect slope stability.

Purpose of the Study:

• To investigate simultaneous responses of volumetric water content and pore gas pressure to rainfall infiltration.
• To understand coupled hydro-gas behavior in landfills.

Main Methods:

• Conducted a simulated rainfall test at the Changzhou landfill.
• Monitored volumetric water content and pore gas pressure.

Main Results:

• Prolonged rainfall increased water content and pore gas pressure, then stabilized.
• Water content changes decreased with depth; pore gas pressure changes increased with depth.
• Increased water content in shallow waste reduced gas permeability, raising pore gas pressure in deeper layers.

Conclusions:

• Findings highlight the novelty of capturing simultaneous liquid-gas phase responses.
• Provides insights into coupled hydro-gas behavior during landfill rainfall infiltration.
• Informs landfill slope stability assessments under hydrologic stress.