Probabilistic Method and its Application for Evaluating Carbonation Life of New-Built Concrete Structures

In order to evaluate carbonation life of new-built concrete structures, two kinds of nondestructive methods have been adopted to test the thickness of concrete cover and ultrasonic velocity of new-built structures. Simultaneously a probabilistic method was proposed based on the relationship between accelerated carbonation rate and ultrasonic velocity. This proposed method has been applied to evaluate the carbonation related lives of two new-built tunnels. The results indicate that even at the nearly same environmental and CO2 combining condition, there exists a big difference in probabilistic carbonation lives between two tunnels i.e. the probabilistic lives of Tunnel A and Tunnel B are 94.0% and 82.3% and the corresponding maximum discrepancies are 11.6% and 27.0%, respectively. Thus it can be concluded that the scattered quality of concrete cover is attributed to the difference in construction technique, which eventually leads to the diversity in evaluated probabilistic carbonation life of two tunnels.

1. Papadakis, V.G., C.G. Vayena and M.N. Fardis. “Fundamental modeling and experimental investigation of concrete carbonation [J],” Materials Journal, 88 (4):363-373, 1991. 2. Saetta, A.V. and R.V. Vitaliani. “Experimental investigation and numerical modeling of carbonation process in reinforced concrete structures, Part I, theoretical formulation,” [J] Cement and Concrete Research, 34(4): 571-579, 2004. 3. Saetta, A.V. and R.V. Vitaliani. “Experimental investigation and numerical modeling of carbonation process in reinforced concrete structures Part II. Practical applications,” [J] Cement and Concrete Research, 35(5):958-967, 2005. 4. Ballim, Y. and J.C. Reid. “Reinforcement corrosion and the deflection of RC beams: an experimental critique of current test method [J],” Cement and Concrete Composites, 25(6): 625-632, 2003. 5. Niu, D.T., Y.Q. Chen and S. Yu. “Model and reliability analysis for carbonation of concrete structures,” [J] Journal of Xi An University of Architecture & Technology, 27 (4):365-369, 1995 (in Chinese). 6. Zhao, S.C. and G.F. Zhao. “Probabilistic model analysis of carbonization life for structure,” [J] Building and Science Research of Sichuan, 3(28):24 -26, 2002 (in Chinese). 7. Ding, B.Y., G.Q. Zheng and D.Y. Kong. “The concrete carbonating and analysis of probabilistic model,” [J] Journal of Zhejiang University of Technology, 34(2): 210-219, 2006 (in Chinese). 8. Zhao, Y.X. and W.L. Jin. Methods of reliability based on serviceability limited state for concrete structural members [J]. Journal of Zhejiang University: Engineering Science, 36 (6): 674 - 679, 2002 (in Chinese). 9. Ba, M.F. and C.X. Qian. “Probablistic carbonation life prediction for li-Lake tunnel based on properties of field concrete cover,” [C] Proc of the International Conference of Microstructure Related Durability of Cementitious Composites. Nanjing: 637-646, 2008. 10. Alekxeef, C.H. The corrosion of reinforcing steel and its protection in concrete reinforced structure [M]. Translated by K.X. Huang and X.Z. Wu Beijing: Chinese Architecture Press, 1988:1-14, (in Chinese). 11. Taylor, H.F.W. Cement chemistry [M]. Thomas Telford Edition, 1997:18-39.
Usage Shares
Total Views
5 Page Views
Total Shares
0 Tweets
0 PDF Downloads
0 Facebook Shares
Total Usage