| Title |
Effects of the Qualities of Ordinary Portland Cement on Chloride Migration of Offshore Concrete |
| Authors |
Park, Sang-Joon ; ShoKwang-Ho |
| Keywords |
Offshore concrete ; Chloride ingress time ; Durability ; Chloride diffusion coefficient |
| Abstract |
In this study, effects of the qualities of ordinary portland cement on chloride migration of offshore concrete were evaluated. Firstly, physical property and chemical composition of six domestic typeⅠordinary portland cements were investigated. And properties of chloride resistance of concrete using six cements were tested. As a result, even thought six cements met the criteria of KS L 5201, physical property and chemical composition of cements were varied with the kinds of cement. The density and fineness of cements showed 3.08 g/㎤ to 3.15 g/㎤ and 3,274 ㎠/g to 3,689 ㎠/g, respectively. In mineral composition, the content of C3S and C2S showed the range of 16.1 % to 47.4 % and 21.6 % to 54.1 %, respectively. The chloride content of concrete was proportional to the chloride content of cement. Also, it could be analyzed that over 65 % of the chloride content of concrete came from cement. Compressive strength of concrete had the difference of maximum 24.8 % at age 7days and maximum 15.7 % at age 28days depending on the kinds of cement. Chloride diffusion coefficient of concrete showed the range of 11.6∼15.7×10-12 ㎡/s at age of 7 days and the range of 4.33∼5.81×10-12 at age of 28 days. Based on chloride diffusion coefficient, it could be analyzed that chloride ingress time of concrete had the difference of maximum 1.5 times depending on the kinds of cement. |