MSWI Bottom Ash Subgrade Aggregate

Utilizes incineration bottom ash as subgrade aggregate, balancing engineering performance with heavy metal leaching risks.

Li, Jue · Qingmeng, Hou · Peng, Junhui · Hu, Hengwu · Vizzari, Domenico

Journal of Traffic and Transportation Engineering (English Edition) 2025

Advantages

Can replace natural aggregates

The physical and chemical properties of bottom ash enable its use as aggregate in subgrade construction, reducing consumption of natural sand and gravel.

Risk manageable

Through risk assessment and management at pretreatment and subgrade design stages, the environmental risks from heavy metal leaching can be effectively controlled.

Regulatory guidance available

The review summarizes regulatory standards for MSWI BA application in road construction across different regions, providing compliance references for engineering practice.

Applications

• Subgrade Fill：Replace natural fill with bottom ash to lower subgrade cost and utilize municipal solid waste.
• Road Base Material：Incorporate bottom ash into road base to reduce reliance on quarried aggregates.
• Waste-to-Material：Convert incineration residue into construction material, promoting waste valorization in transport infrastructure.