Probability of Performance Failure and Change of Roughness Coefficient According to Accumulation of Debris in Storm Sewer

토사적체에 따른 우수관의 조도계수 변화와 성능불능확률

  • 권혁재 (청주대학교 토목환경공학과)
  • Received : 2010.07.22
  • Accepted : 2010.10.06
  • Published : 2010.10.31

Abstract

Reliability model which can calculate the probability of performance failure of storm sewer was developed considering change of roughness coefficient in this study. Roughness coefficient should be re-evaluated due to accumulations of debris in sewer pipe. Therefore, roughness coefficient according to depth of debris in circular sewer pipe was determined for the present study. Reliability analysis was performed with the new roughness coefficient. After the analysis, it was found that capacity of storm sewer can be significantly decreased and probability of performance failure of storm sewer can be significantly increased by increasing the depth of debris in storm sewer. In this study, reliability model was applied for the Daegu and Jeonju using new roughness coefficient which was determined according to accumulation of debris in circular storm sewer. It was observed that if the depth of debris is increased, roughness coefficient is increased simultaneously and probability of performance failure of storm sewer is significantly increased.

본 연구에서는 우수관의 조도계수의 변화에 따른 성능불능확률을 산정할 수 있는 신뢰성 모형이 개발되었다. 조도계수는 우수관의 토사의 적체에 따라 다시 산정되었으며 새로운 조도계수를 이용하여 신뢰성 해석이 수행되었다. 해석결과, 우수관에 적체되는 토사의 깊이가 증가함에 따라 우수관의 용량은 크게 감소하고 성능불능확률은 크게 증가함을 알 수 있었다. 본 연구에서는 우수관에 적체되는 토사의 깊이에 따라 산정된 조도계수를 사용한 신뢰성 모형을 대구와 전주에 적용하였다. 원형 우수관에 적체된 토사의 깊이가 증가할수록 우수관의 조도계수는 커지고 성능불능확률도 역시 크게 증가 하는 것을 알 수 있었다.

Keywords

References

  1. 김지성, 이찬주, 김원 (2007a) 실측 수위에 의한 자갈하천의 조도계수 산정. 한국수자원학회논문집, 한국수자원학회, 제 40권, 제 10호, pp. 755-768.
  2. 김지성, 이찬주, 김원 (2007b) 현장실측에 의한 조도계수 산정의 불확실도 평가. 한국수자원학회논문집, 한국수자원학회, 제 40권, 제 10호. pp. 801-810.
  3. 이철규, 현인환, 독고석, 김형준 (2005) 강우 확률년수의 설정이 우수관거 설계에 미치는 영향. 상하수도학회지, 대한상하수도학회, 제 19권, 제 5호, pp. 647-654.
  4. Ang, A. and Tang, W.H. (1984) Probability Concepts in Engineering Planning and Design. John Wiley and Sons, Inc. New York.
  5. Brater, E.F., King, H.W., Lindell, J. E. and Wei, C. Y. (1996). Handbook of hydraulics, McGraw-Hill, New York.
  6. Frankel, E.G. (1988) Systems Reliability and Risk Analysis. Klume Academic Publishers.
  7. Kwon, H.J. and Lee, C.E. (2008a) Reliability analysis of pipe network regarding transient flow. KSCE Journal of Civil Engineering, Korean Society of Civil Engineers, Vol. 12, No. 6, pp. 409-416. https://doi.org/10.1007/s12205-008-0409-1
  8. Kwon, H.J. and Lee, C.E. (2008b) Reliability analysis for the probability of pipe breakage. Journal of Korean Society of Water and Wastewater, KSWW, Vol. 22, No. 6, pp. 609-617.
  9. Kwon, H.J. and Lee, C.E. (2009) Sensitivity analysis for friction coefficient on the estimations of probability of pipe breakage. KSCE Journal of Civil Engineering, Korean Society of Civil Engineers, Vol. 13, No. 6, pp. 453-462. https://doi.org/10.1007/s12205-009-0453-5
  10. Modarres, M. (1999) Reliability Engineering and Risk Analysis. Marcel Dekker.