Effect of low temperature on hydration performance of the complex binder of silica fume-portland cement

Abstract

By analyzing the mechanical properties, composition of hydrates, content of Ca(OH)₂ and microstructure of the complex binder of silica fume-Portland cement, which cured at constant low temperatures(+5-−10 °C), the effect of different low temperatures on hydration performance of the complex binder at the age of 3, 7 days and 14 days was researched. Experimental results show that hydration processes of the complex binder can be restricted by low temperature. Reducing the curing temperature could cause compressive strength and flexural strength of the complex binder to decrease significantly. The gradient difference between strength diminishes, content of Ca(OH)₂ in hydrates reduces, and compactness of the microstructure weakens. Therefore mixing with silica fume can modify various performance indicators of the complex blinder, but reducing the curing temperature restricts the pozzolanic activity of silicon fume.

Keywords

low temperature / strength / content of Ca(OH)₂ / XRD analysis / SEM

References

[1] Dang Yudong Influence of Shrinkage Reducing Admixture and Internal Curing on Volume Stability of Cement Based Material[D], 2012 Chongqing Chongqing University

[2] Niu D, Xiao Q, Zhu Wenping Concrete Damage and Neutralization under Coupling Effect of Carbonation and Freeze-Thaw Cycles[J]. Journal of Wuhan University of Technology-Mater. Sci. Ed., 2012 353-357.

[3] Wang Baomin Study on Performance and Mechanism of High Performance Concrete with Nano-SiO₂ [D], 2009 Dalian Dalian University of Technology

[4] Wan Y An Advanced Construction Technology for Cable-stayed Bailey Arch[C]. Proceedings of ARCH’ 10-the 6th International Conference on Arch Bridges, Shanghai, 2010

[5] Deng Shouchang State of Theoretical Study of Cooling Calculation for Concrete Heat-Saving [J]. Journal of Huizhou University: Natural Science Edition, 2013, 33(6): 6-20.

[6] Li K-f, Zeng Q Influence of Freezing Rate on Cryo-Damage of Cementitious Material[J]. Science A: An International Applied Physics & Engineering Journal, 2009 17-21.

[7] Sheng Z, Hu Y, Xue J, . SO₂ Poisoning and Regeneration of Mn-Ce/TiO₂ Catalyst for Low Temperature NO_x Reduction with NH3[J]. Journal of Rare Earths, 2012 676-682.

[8] Miao Miao Influence of Binder Material Composition and Temperature on the Deformation of Shrinkage-Compensating Concrete[D], 2012 Beijing Tsinghua University