Sensitive evaluation on early cracking tendency of concrete with inclusion of light-burnt MgO

Abstract

The advanced temperature and stress test machine was introduced to determine the early cracking tendency of concrete with inclusion of light-burnt MgO under full restraint by tracking the development of thermal, physical and deformation properties. Results showed that light-burnt MgO being incorporated ranging between 4 wt% and 6 wt% of cementitious materials was beneficial to increase the maximum compressive stress and cracking stress of concrete by 0.37 MPa and 0.2 MPa on average respectively. The second zero stress temperature was reduced by 11.4 °C and the maximum temperature was slightly reduced while cracking thermal impact was significantly enhanced from 59.8 °C to 66.2 °C. Sensitive anti-cracking coefficient F was forwarded to assess the early cracking tendency of concrete and the inclusion of 4 wt% light-burnt MgO with activity of 109 s ranked the best in crack resistance.

Keywords

crack resistance / cracking stress / light-burnt MgO / concrete / sensitive evaluation

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