# 롤러 전압 콘크리트 포장의 공기량 및 기포간격계수와 장기 내구성의 상관관계 분석을 위한 실험적 연구

Lee, Jun Hee;Lee, Seung Woo
이준희;이승우

• Received : 2015.11.30
• Accepted : 2016.01.18
• Published : 2016.02.15
• 14 14

#### Abstract

PURPOSES : The use of roller-compacted concrete pavement (RCCP) is an environmentally friendly method of construction that utilizes the aggregate interlock effect by means of a hydration reaction and roller compacting, demonstrating a superb structural performance with a relatively small unit water content and unit cement content. However, even if an excellent structural performance was secured through a previous study, the verification research on the environmental load and long-term durability was conducted under unsatisfactory conditions. In order to secure longterm durability, the construction of an appropriate internal air-void structure is required. In this study, a method of improving the long-term durability of RCCP will be suggested by analyzing the internal air-void structure and relevant durability of roller-compacted concrete. METHODS : The method of improving the long-term durability involves measurements of the air content, air voids, and air-spacing factor in RCCP that experiences a change in terms of the kind of air-entraining agent and chemical admixture proportions. This test should be conducted on the basis of test criteria such as ASTM C 457, 672, and KS F 2456. RESULTS : Freezing, thawing, and scaling resistance tests of roller compacted concrete without a chemical admixture showed that it was weak. However, as a result of conducting air entraining (AE) with an AE agent, a large amount of air was distributed with a range of 2~3%, and an air void spacing factor ranging from 200 to $300{\mu}m$ (close to $250{\mu}m$) coming from PCA was secured. Accordingly, the freezing and thawing resistance was improved, with a relative dynamic elastic modulus of more than 80%, and the scaling resistance was improved under the appropriate AE agent content rate. CONCLUSIONS : The long-term durability of RCCP has a direct relationship with the air-void spacing factor, and it can be secured only by ensuring the air void spacing factor through air entraining with the inclusion of an AE agent.

#### Keywords

RCCP;roller-compacted concrete;air spacing factor;surface scaling resistance test;freezing and thawing resistance test;durability

#### References

1. Farshid Vahedifard., Mahmoud Nili., Christopher L. Meehan., 2010, Assessing the effects of supplementary cementitious materials on the performance of low-cement roller compacted concrete pavement, Construction and Building Materials, Vol. 24, No. 12, pp. 2528-2535. https://doi.org/10.1016/j.conbuildmat.2010.06.003
2. ASTM C672, Standard Test Method for Scaling Resistance of Concrete Surfaces Exposed to Deicing Chemicals.
3. ASTM C457, Standard Test Method for Microscopical Determination of Parameters of the Air-Void System in Hardened Concrete.
4. ASTM C1170, Standard Test Method for Determining Consistency and Density of Roller-Compacted Concrete Using a Vibrating Table.
5. Dale Harrington et al., 2010, Guide for Roller Compacted Concrete Pavements, National CP Tech Center.
6. Han, H. S., and Jin, Y. M., 2009, The Future of Concrete Admixture Industry for Low Carbon, Green Growth, Journal of the Korean Concrete Institute, Vol. 21, No. 4, pp. 41-43.
7. Hwang, H. J., and Kim, J. G., 2010, Evaluation of Chloride Attack Resistibility of Concrete Damaged Due to Freezing-Thawing, Master's Thesis, Dong-Eui University.
8. KS F 2456, Standard test method for resistance of concrete to rapid freezing and thawing.
9. Lee, B. C., Kim, J. C., Um, J. Y., Yu, T. S., and Lim, S. W., 1996, An Experimental Study on the Concrete Pavement Method for Early Traffic Opening, Korea Expressway Corporation, Practical Reports, pp. 12-13.
10. Lee, C.. H., Kim, Y. K., Kang, J. G., Park, C. W., and Lee, S. W., 2011, A Study on Construction Methods of Roller Compacted Concrete Pavement for Bike Roads, Journal of the Korean Society of Road Engineers, Vol. 13, No. 2 pp. 103-114.
11. Luhr, D. R., 2006, Frost Durability of Roller-Compacted Concrete Pavements, Portland Cement Association.
12. Richard Pleau, Michel Pigeon, Jean-Luc Laurencot, 2001, Some Findings of the Usefulness of Image Analysis for Determining the Characteristics of Air-Void System on hardened Concrete, Cement & Concrete Composites 23, pp. 237-246. https://doi.org/10.1016/S0958-9465(00)00079-2
13. Song, S. H., and Lee, S. W., 2015, A Study on the Gradation Effect of the Property of Roller Compacted Concrete Pavement, Journal of the Korean Society of Road Engineers, Vol. 17, No. 3 pp. 49-58.
14. Yun, K. K., Jeong, W. K., Jun, I. K., and Lee, B. H., 2004, Analysis of Air Voids System Using Image Analysis Technique in Hardened Concrete, Journal of the Korean Concrete Institute, Vol. 16, No. 6. pp. 740-750.
15. ACI 325.10R-25, Report on Roller Compacted Concrete pavements.

#### Acknowledgement

Grant : 온실가스 배출 최소화를 위한 친환경 포장도로(Eco-Road)

Supported by : 국토교통과학기술진흥원