Impact of municipal solid waste incineration bottom ash on the properties and frost resistance of clay bricks

This paper presents an experimental study on the properties, structure and durability (frost resistance: one-side and all-sides freezing and thawing method) of fired clay bricks containing clay and municipal solid waste incineration (MSWI) bottom ash (BA). BA is a non-hazardous substance containing mainly CaO and SiO2, and also a low content of heavy metals. Clay was replaced with the BA up to 15% by weight. The bricks were fired at 1000 °C temperature and maintained at the maximum heat for 1 h. According to the research data, BA addition has an effect on the structure and properties of clay bricks. Higher content of BA in the mix of clay bricks leads to the increase of water absorption and total porosity and the decrease of density, and, therefore, lowers the durability (frost resistance) of clay bricks. In clay bricks with higher BA content the typical brick surface damages start appearing after the lower number of freezing and thawing cycles (both in one-side and all-sides freezing and thawing method). Nevertheless, all samples tested for resistance to freezing and thawing in one-side method is classified as F2 class according to the LST EN 772-22:2019 standard (severe weather resistance).