High strength flowable lightweight concrete incorporating low C3A cement, silica fume, stalite and macro-polyfelin polymer fibres

Abstract Lightweight concrete (LWC) can reduce the self-weight of structures and can save material and labour costs in industry. Despite these merits, the application of lightweight concrete is mostly limited because of low compressive strength, often 90 MPa) and high workability (slump flow value > 550 mm). The workability, mechanical properties, durability, microstructure and aggregates distribution of the high strength flowable lightweight concrete (HFLWC) were investigated. Key mix parameters were examined including Portland and low C3A cements, fly ash (FA), undensified silica fume (UDSF), river sand and silica sand. Stalite was used as a high performance lightweight coarse aggregate. In addition, four volume fractions of macro-polyfelin polymer fibres (MPP), 0.5%, 1%, 1.5% and 2%, were added to investigate the effect on the flexure strength and different durability indicators. It was found that the incorporation of stalite, low w/b ratio, low C3A cement and UDSF can produce LWC with exceptional strength and flowability. The results showed that HFLWC could be produced with density