The influence of calcium nitrate on setting and hardening rate of Portland cement concrete at different temperatures

3rd International Conference on Innovative Materials, Structures and Technologies

Kiaite, A.^1 ; Pundiene, I.^1 ; Skripkiunas, G.^1

Department of Building Materials, Vilnius Gediminas Technical University, Sauletekio al.11, Vilnius, Lithuania^1

关键词: Antifreeze admixtures;    Binding materials;    Hardened concrete;    Limestone cements;    Long-term strength;    Multifunctional additives;    Portland cement concretes;    Technological characteristics;   

Others  :  https://iopscience.iop.org/article/10.1088/1757-899X/251/1/012017/pdf
DOI  :  10.1088/1757-899X/251/1/012017

来源: IOP

【 摘 要 】

Calcium nitrate in mortars and concrete is used as a multifunctional additive: As set accelerator, plasticizer, long term strength enhancer and as antifreeze admixture. Used binding material and the amount of calcium nitrate, affect the characteristics of the concrete mixture and strength of hardened concrete. The setting time of the initial and the final binding at different temperatures of hardening (+ 20 °C and + 5 °C) of the pastes made of different cements (Portland cement CEM I 42.5 R and Portland limestone cement CEM II/A-LL 42.5 R) and various amounts of calcium nitrate from 1 % until 3 % were investigated. The effect of calcium nitrate on technological characteristics of concrete mixture (the consistency of the mixture, the density, and the amount of air in the mixture), on early concrete strength after 2 and 7 days, as well as on standard concrete strength after 28 days at different temperatures (at + 20 °C and + 5 °C) were analysed.