The flexural toughness and ductility of portland cement-based binders reinforced with wollastonite micro-fibres

✍ Scribed by Norman M.P. Low; J.J. Beaudoin

• Publisher: Elsevier Science
• Year: 1994
• Tongue: English
• Weight: 474 KB
• Volume: 24
• Category: Article
• ISSN: 0008-8846
• DOI: 10.1016/0008-8846(94)90050-7

✦ Synopsis

An analysis of the flexural toughness and ductility of Portland cement-based binders reinforced with natural woUastonite micro-fibres is reported. The flexural toughness was calculated as the sum of finite area increments under the entire load-deflection curve and the ductility was determined from the deflection in the post-peak region. Load-deflection curves were created with numerical data obtained in flexural tests employing the computer controlled MTS system. Five series of specimens were investigated. A series of specimens made with cement and blended with different amounts of silica fume served as reference systems. The other four series of specimens contained seven different concentrations of wollastonite microfibres, each series having a different amount of silica fume. Results showed that the flexural toughness of the cement-silica fume system decreased non-linearly as the amount of ~lica fume in the mixture increased. The flexural toughness of the cement-woUastonite composite system and the cement-silica fume-wollastonite composite system was observed to increase almost linearly as the concentration of the woUastonite micro-fibres in the composite matrices increased. Toe increase of the flexural toughness with increasing concentration of woUastonite microfibres in the composite mixtures was influenced by the amount of silica fume. Toe ductility of the composite matrices increased nonlinearly with increase in concentration of wollastonite micro-fibres in the composite mixtures. The amount of silica fume in the composite matrix had no significant role in modification of ductility in the composite system. Differences in observed properties are discussed.