The effect of natural bamboo fiber and basalt fiber on the properties of autoclaved aerated concrete

Abstract

Autoclaved aerated concrete (AAC) has the advantages of low density and good thermal insulation performance, but its mechanical properties are not so good. In this experiment, natural bamboo fiber and basalt fiber were used to strengthen AAC, and the effect of fiber content and fiber length on the AAC properties was investigated. The experimental results showed that with the increase of fiber content, the slurry fluidity, foaming height of AAC mixture decreased, the area of hazardous pore, the density, mechanical strength and thermal conductivity of AAC increased. As the fiber length increased, similar results were observed in the mechanical strength and thermal conductivity of AAC but not found in the slurry fluidity, foaming curve and pore structure. By contrast, natural bamboo fiber had greater impact on the properties of AAC than basalt fiber. The scanning electron microscope (SEM) results showed natural bamboo did not react with AAC matrix and the fiber was pulled out from AAC matrix when the AAC cracked, while basalt fiber was corroded in alkaline matrix and broke with AAC matrix together under external load.