DOI QR코드

DOI QR Code

급경사 자갈하상 만곡수로의 최대세굴심 산정공식 평가

Estimation methods of maximum scour depth in steep gravel-bed bend channel

  • 조재웅 (강릉원주대학교 토목공학과) ;
  • 남아름 ((주)리버앤텍) ;
  • 우태영 ((주)바우컨설탄트 기술연구소) ;
  • 박상덕 (강릉원주대학교 토목공학과)
  • 투고 : 2015.12.06
  • 심사 : 2016.03.31
  • 발행 : 2016.06.30

초록

본 연구는 급경사 자갈하상 만곡수로의 이동상 수리실험을 이용하여 만곡부 최대세굴심 산정공식들의 적용성을 평가하였다. 평균입경 43mm의 하천자갈을 $90^{\circ}$ 만곡 급경사 개수로에 포설하고 유량과 하상경사에 따른 만곡부의 최대세굴심을 조사하고 세굴심 공식으로 산정한 최대세굴심과 비교하였다. 자갈하상 만곡부 국부세굴은 유입부의 하상경사 0.02이상 $F_r$ 0.95이상에서 발생하였다. 이 수로에서 Lacey공식과 Zeller공식을 제외한 기존 세굴심 산정공식들은 최대세굴심을 과대 추정하는 것으로 나타났다. 하상재료를 고려한 Lacey공식과 접근경사와 만곡도를 반영한 Zeller공식은 급경사 자갈하상 만곡부의 최대세굴심 평가에 적용될 수 있는 것으로 판단된다.

The existing methods to estimate the maximum scour depth in the bend of steep gravel bed channel have been evaluated by the hydraulic movable-bed experiments. In the $90^{\circ}$ bend steep-slope channel paved with the fluvial gravels which are uniform in size and have a mean diameter of 43mm, the maximum scour depths due to the flow discharge and the gradient of bed slope have been investigated and compared with the scour depth computed from the equations. The local scour has occurred in conditions that the bed slope is steeper than 0.02 and the $F_r$ is greater than 0.95. Except Lacey's equation and Zeller's equation, the existing methods computing the maximum scour depth overestimate the maximum scour depth in the steep channel with the very coarse gravel bed. However, Lacey's equation with the bed material size and Zeller's equation considering the approach channel gradient and the bend angle may be relatively used to estimate the scour depth in bend of the steep gravel-bed river.

키워드

참고문헌

  1. Blench, T. (1969), Mobile-Bed Fluviology, University of Alberta Press, Edmonton.
  2. Brown, S.A., and E.S. Clyde (1989), Design of Riprap Revetment, Hydraulic Engineering Circular No. 11, FHWA-IP-89-016, Prepared for the Federal Highway Administration, Washington, D.C..
  3. Ko, J.U. (1975), "A Study on fluvial phenomena in the Bended Alluvial Rivers", Journal of Korea Water Resources Association, Vol. 8, No. 2, pp.75-80.
  4. Lacey, G., Stable Channels in Alluvium, Proceedings of the Institute of Civil Engineers, v. 229., 1930.
  5. Lane, E. W. (1957), A Study of the Shape of Channels Formed by Natural Streams Flowing in Erodible Material, Missouri River Division Sediments Series No. 9, U.S. Army Engineer Division, Missouri River, Corps of Engineers, Omaha, Nebraska.
  6. Langbein, W.B. and L.B. Leopold (1996), River Meanders - Theory of Minimum Variance, USGS Professional Paper 422-H.
  7. Laursen, E.M. (1960), Scour at Bridge Crossings, May, Journal Hydraulic Division, ASCE, v. 92, No. HY3.
  8. Leopold, L.B., and M.G. Wolman (1960), River Meanders, Geologic Society of America Bulletin, v. 32, pp. 769-794.
  9. Liu, H.K., F.M. Chang, and M.M. Skinner (1961), Effect of Bridge Construction on Scour and Backwater, Department of Civil Engineering, Colorado State University, Report Number CER60HKL22.
  10. Mussetter, R. A., Lagasse, P.F., Harvey, M.D., and Anderson, C.E. (1994), Sediment and Erosion Design Guide, November, prepared for the Albuquerque Metropolitan Arroyo Flood Control Authority, RCE Reference Number 90-560.
  11. Pemberton, E.L. and Lara, J.M. (1984). Computing Degradation and Local Scour, Technical Guideline for Bureau of Reclamation, Engineering and Research Centre, Bureau of Reclamation, Denver, Colorado, USA.
  12. Richardson, E.V., L.J. Harrison, and S.R. Davis (1991), Evaluating Scour at Bridges, FHWA-IP-90-017, Hydraulic Engineering Circular No. 18, U. S. Department of Transportation, FHWA, Turner Fairbanks Highway Research Center, McLean, Virginia.
  13. Simons, Li & Associates, Inc. (1989a), Design Guidelines & Criteria, Channels & Hydraulic Structures on Sandy Soil, June, prepared for Urban Drainage and Flood Control District, Denver, Colorado and The City of Aurora, Colorado.
  14. Simons, Li & Associates, Inc. (1989b), Standards Manual for Drainage Design and Floodplain Management in Tucson, Arizona, December, prepared for the City of Tucson Department of Transportation, Engineering Division.
  15. Song, J.W. Choi, I.H., and Kim, J.H (1994)., "A Study on Selected Transverse Bed Slope Models in Channel Bend", Journal of The Korea Society of Civil Engineers, Vol. 14, No. 6, pp.1395-1404.
  16. U.S. Army Corps of Engineers (1993), Velocity and Scour Prediction in River Bends, Waterways Experiment Station.
  17. Yoon, S.E., Lee, J.T. (1990), "Flow Characteristics for the Variation of Radius of Curvature in Open Channel Bends", Journal of Korean Association of Hydrological Sciences, Vol. 23, No. 3, pp.435-444.
  18. Zeller, M.E. (1981), Scour Depth Formula for Estimation of Toe Protection Against General Scour, Pima County Department of Transportation and Flood Control District, Tucson, Arizona.