Crack Resistance of Concrete with Incorporation of Light-Burnt MgO

Abstract:

The advanced Temperature and Stress Test Machine was introduced to evaluate the cracking resistance of concrete with inclusion of light-burnt MgO under full restraint by tracking thermal and deformation development. Results showed that light-burnt MgO being incorporated ranging between 4 per cent and 6 per cent by mass of cementitious materials was beneficial to increase the maximum compressive stress and cracking stress of concrete by 0.37MPa and 0.2MPa on average respectively. The maximum temperature was slightly reduced from 59.8°C to 66.2°C while cracking temperature was significantly decreased from 0.8°C to minus 5.6°C. Sensitive anti-cracking coefficient F was forwarded to assess the early cracking tendency of concrete and in general, inclusion of 4 per cent light-burnt MgO with activity of 109s was rated the best in crack resistance.

• Periodical: Advanced Materials Research (Volumes 168-170)
• Pages: 1348-1352
• DOI: https://doi.org/10.4028/www.scientific.net/AMR.168-170.1348
• Online since: December 2010
• Authors: Xia Chen, Hua Quan Yang, Shi Hua Zhou, Jian Jun Yan
• Keywords: Concrete, Crack Resistance, Cracking Temperature, Evaluation, MgO

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