Journal of Korean Society of Water and Wastewater (상하수도학회지)

The Korean Society of Water and Wastewater (대한상하수도학회)
권호 표지

A Statistical Methodology for Evaluating the Residual Life of Water Mains

상수관로의 잔존수명 평가를 위한 통계적 방법론

  • 박수완 (부산대학교 사회환경시스템공학부) ;
  • 최창록 (부산대학교 대학원 사회환경시스템공학과) ;
  • 김정현 (K-water 연구원 상하수도 연구소) ;
  • 배철호 (K-water 연구원 상하수도 연구소)
  • Received : 2009.02.17
  • Accepted : 2009.06.10
  • Published : 2009.06.15
Download PDF
⟨ Previous Next ⟩

Abstract

This paper provides a method for evaluating a residual life of water mains using a proportional hazard model(PHM). The survival time of individual pipe is defined as the elapsed time since installation until a break rate of individual pipe exceeds the Threshold Break Rate. A break rate of an individual pipe is estimated by using the General Pipe Break Model(GPBM). In order to use the GPBM effectively, improvement of the GPBM is presented in this paper by utilizing additional break data that is the cumulative number of pipe break of 0 for the time of installation and adjusting a value of weighting factor(WF). The residual lives and hazard ratios of the case study pipes of which the cumulative number of pipe breaks is more than one is estimated by using the estimated survival function. It is found that the average residual lives of the steel and cast iron pipes are about 25.1 and 21 years, respectively. The hazard rate of the cast iron pipes is found to be higher than the steel pipes until 20 years since installation. However, the hazard rate of the cast iron pipes become lower than the hazard rates of the steel pipes after 20 years since installation.

Keywords

Acknowledgement

Supported by : 한국수자원공사 K-water

References

  1. 박재빈 (2007). 생존분석 이론과 실제. pp. 181-297. 신광출판사, 서울
  2. 송혜향, 정갑도, 이원철 (2007). 생존분석. pp. 85-146. 청문각, 서울
  3. 환경부 (2003). 물관리종합대책 실천계획. pp. 3-6. 환경부, 서울
  4. 환경부 (2007). 국가 물 수요관리 종합대책. pp. 19-25. 환경부, 서울
  5. 환경부 (2008). 2008 환경백서. pp. 453-489. 환경부, 서울
  6. Randall C. Conner. (1999). PIPELINE SAFETY, RELIABLITY, AND REHABILITATION. pp. 353-381. American Society of Civil Engineering, U.S.A
  7. Andreou, S. A., Marks, D. H. and Clark, R. M. (1987) 'A New Methodology for Modeling Break Failure Patterns in Deteriorating Water Distribution Systems: Applications.' Advances in Water Resources, Vol. 10, pp. 11-20 https://doi.org/10.1016/0309-1708(87)90003-0
  8. Allison, P. D. (1995). Survival Analysis using SAS: A Practical Guide, Cary, SAS Institute, U.S.A. pp. 173-174
  9. Collet, D. (2003). Modelling Survival Data in Medical Journal of Korean Society of Water and Wastewater Research. pp. 80-87 . Chapman & Hall/CRC, Boca Raton, U.S.A.
  10. Constantine, A. G. and Darroch, J. N., In S. Osaki, D. N. P. Murthy. (1993). Pipeline Reliability: Stochastic Models in Engineering, Technology and Management, World Scientific, Singapore
  11. Cox, D. R. (1972). 'Regression Models and Life Tables.' Journal of Royal Statistic Society, Vol. 34, No. 2, pp. 187-220
  12. Klein, J. P. and Moeschberger, M. L. (2003). Survival Analysis: Techniques for Censored and Truncated Data. Springer-Verlag, pp. 374-379.New York
  13. Li, D. and Haims, Y. Y. (1992). 'Optimal Maintenance-related Decision Making for Deteriorating Water Distribution Systems 1. Semi-Markovian model for a water main.' Water Resources Research, Vol. 28, No. 4, pp. 1053-1061 https://doi.org/10.1029/91WR03035
  14. Loganathan, G. V., Park, S., and Sherali, H. D. (2002). 'Threshold break rate for pipeline replacement in water distribution systems.' Journal of Water Resources Planning and Management, ASCE, Vol. 128, No. 4, pp. 271-279 https://doi.org/10.1061/(ASCE)0733-9496(2002)128:4(271)
  15. Park, S. (2004). 'Identifying the Hazard Characteristics of Pipes in Water Distribution Systems by using the Proportional Hazards Model: 2. Applications.' KSCE Journal of Civil Engineering, Vol. 8, No. 6, pp. 669-677 https://doi.org/10.1007/BF02823558
  16. Park, S. and Loganathan, G. V. (2002). 'Optimal Pipe Replacement Analysis with a New Pipe Break Prediction Model.' Journal of the Korean Society of Water and Wastewater, Vol. 16, No. 6, pp. 710-716
  17. Therneau, T. M. and Grambsch, P. M. and Fleming, T. R. (1990). 'Martingale-based residuals for survival models.' Biometrika, Vol. 77, No. 1, pp. 147-160 https://doi.org/10.1093/biomet/77.1.147