Properties of Lightweight Concrete Masonry Units Made from Lightweight Aggregates

Abstract:

In the paper the properties of concrete masonry unit (CMU) made from sedimentary lightweight aggregate (LWA) were investigated. The main variables include water to cementitious material ratio (W/CM), filling ratio of paste or mortar in voids between coarse aggregate particles (Fv), filling ratio of sand in mortar (Fm), and cement replacement level by slag (Sc). Test results of representative CMU specimens show that unit weight ranged from 1585 to 1743 kg/m3, which was 30-25% lower than that for a normal weight CMU (2300 kg/m3); compressive strengths ranged from 8.4 to 18.7 MPa; water absorption was found to vary between 0.05 to 0.13 g/cm3; and thermal conductivity ranged from 0.27 to 0.41 W/mK. The research findings demonstrate that the use of sedimentary LWA as coarse aggregate in various concrete mixtures could produce high performance lightweight CMU, which comply with the requirements of Chinese National Standards (CNS) standards.

• Periodical: Advanced Materials Research (Volumes 150-151)
• Pages: 1588-1594
• DOI: https://doi.org/10.4028/www.scientific.net/AMR.150-151.1588
• Online since: October 2010
• Authors: Chao Wei Tang, Kuo Haung Fan, Wen Po Tsai, How Ji Chen
• Keywords: Concrete Masonry Unit, Lightweight Aggregate

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