BOTTOM-UP

The BOTTOM-UP (Secure Valorization of Incinerator Bottom Ash in Road Foundations) project, supported by the Win4Collective program (Call 2024), addresses the challenge of increased road infrastructure maintenance in Wallonia. With road density twice as high as in the rest of Belgium, the Region faces a growing need for secondary materials to replace natural resources.

• Incinerator bottom ash from household waste incineration represents a potential solution, provided its complex chemistry is properly controlled.

• The goal is to establish criteria ensuring that bottom ash, whether cement-treated or not, can be used safely as a foundation material.

• A key focus is on preventing the formation of harmful phases over the long term (risk of pavement cracking) and ensuring the overall durability of the road structure.

• Led by the CTP (Centre Terre et Pierre asbl) in partnership with the CRR (Centre de recherches routières), the

  BOTTOM-UP project seeks to reconcile circular economy principles with technical performance, keeping available bottom ash in the category of materials proven to be compliant and risk-controlled.