Journal of Hydraulics

Journal of Hydraulics

Laboratory Experimental Measuring speed and WaveLenghth of Impact Waves Generated by Mass Movement in Dam Reservoirs Using Laser Surface Profilometry

Document Type : Research Article

Authors
Yaser Shakeri 1
Ahmad Darudi 2
Jalal Bazargan 3
1 PhD student in Physics, Optics and Lasers, University of Zanjan
2 Associate Professor, Department of Physics, Faculty of Science, University of Zanjan
3 Prof. Department of Civil Engineering, University of Zanjan, (Zanjan, Iran)
10.30482/jhyd.2025.519933.1731
Abstract
The study of the characteristics of waves generated by the collapse of rock masses in dam reservoir walls is of great importance. Factors influencing the wave flow over the body and crest of a dam include the length, height, and speed of the waves generated by the collapse of rock masses due to various factors. For this reason, in the present study, the wave parameters mentioned were measured for the first time using laser surface profiling in a pool with dimensions of 12.5 meters in length, 6.5 meters in width, and 1 meter in height at Zanjan University, Iran, due to the collapse of a mass in this reservoir. The experiments were conducted using a sliding mass weighing 200 kilograms and for a water depth of 75 cm. The laser setup consisted of two arrays (with a 76 cm distance between them), where each array contained 15 lasers arranged in pairs facing each other. Using these lasers and a DSLR camera, after the mass was dropped onto the inclined surface, the variations in wave height over time were recorded. Then, using the recorded images and laser surface profiling, the wave height was first measured, and then, using the changes in height, the wavelength was calculated. Following this, by measuring the time it took for the wave to pass in front of the two laser arrays, the wave speed was also obtained. It is worth noting that the camera's frame rate was 0.04 seconds. The experimental results indicate that the measured wave speed using the proposed method was 2.67 meters per second, while the wave speed calculated using the wave speed formula (C=√gh) was 2.71 meters per second, showing a difference of 1.48%, which demonstrates the high accuracy of the proposed measurement method.
Keywords : Mass fall,impact waves,wavelength,wave speed,laser surface profilometry
Keywords
Mass fall
impact waves
wavelength
wave speed
laser surface profilometry
Subjects
Aricò, C., Corato, G. & Tucciarelli, T. (2010). Discharge estimation in open channels by means of water level hydrograph analysis. Journal of Hydraulic Research, 48, 612–619. https://doi.org/ 10.1080/00221686.2010.507352.
Bai, R., Zhu, D., Chen, H. & Li, D. (2019). Laboratory study of secondary flow in an open channel bend by using PIV. Water, 11, 659. https://doi.org/10.3390/w11040659.
Bin Asad, S.M.S., Lundström, T.S., Andersson, A.G., Hellström, J.G.I. & Leonardsson, K. (2019). Wall shear stress measurement on curve objects with PIV in connection to benthic fauna in regulated rivers. Water, 11, 650. https://doi.org/10.3390/ w11040650.
Bradley, A.A., Kruger, A. & Meselhe, E.A. (1999). Flow measurement in streams using video imagery. Water Resources Research, 38, 51. https://doi.org /10.1029/2002WR001317.
Fujita, I., Muste, M. & Kruger, A. (1998). Large-scale particle image velocimetry for flow analysis in hydraulic engineering applications. Journal of Hydraulic Research, 36, 397–414. https://doi.org/ 10.1080/00221689809498626.
Fujita, I. & Aya, S. (2000). Refinement of LS-PIV technique for monitoring river surface flows. Building Partnerships, Proceedings, https://doi.org/ 10.1061/ 40517(2000)312.
Fujita, I. & Tsubaki, R. (2002). A novel free-surface velocity measurement method using spatio-temporal images. Proceedings of the Joint IAHR & ASCE Conference on Hydraulic Measurements & Experimental Methods, Estes Park, 28 July-1 August 2002. https://doi.org/10.1061/ 40655(2002)85.
Gunawan, B., Sun, X. & Sterling, M. (2012). The application of LS-PIV to a small irregular river for inbank and overbank flows. Flow Measurement and Instrumentation, 24, 1–12. https://doi.org/10.1016/ j.flowmeasinst.2012.02.001.
Heng, W., Zhao, R., Gan, X. & Ma, X. (2019). Measuring surface velocity of water flow by dense optical flow method. Water, 11(11), 2320. https://doi.org/ 10.3390/w11112320.
Fang, S.Q., Chen, Y.P., Xu, Z.S., Otoo, E. & Lu, S.Q. (2019). An improved integral model for a non-buoyant turbulent jet in wave environment. Water, 11(4), 765. https://doi.org/10.3390/w11040765
Katakura, K. & Alain, P. (2002). Ultrasonic measurement method for transversal component of water flow velocity. In: Proceedings of the International Symposium on Underwater Technology, pp. 45–48, Tokyo, Japan, 16–19 April. https://doi.org/10.1109/UT.2002.1002381
Kawanisi, K., Razaz, M. & Ishikawa, K. (2012). Continuous measurements of flow rate in a shallow gravel-bed river by a new acoustic system. Water Resources Research, 48, 5547. https://doi.org/ 10.1029/2012WR012064.
Kim, Y., Evans, R.G. & Iversen, W.M. (2008). Remote sensing and control of an irrigation system using a distributed wireless sensor network. IEEE Transactions on Instrumentation and Measurement, 57, 1379-1387. https://doi.org/10.1109/TIM.2008. 917198.
Maleki, F. & Bazargan, J. (2025). Three-dimensional numerical modeling of impulsive wave generation and propagation induced by landslides on dam reservoir slopes. Journal of Hydraulics, 20(2), 37–52. (In Persian)
Milan, S., Roger, B. & Vaclav, H. (1993). Image processing, analysis, and machine vision. Chapman & Hall Computing, Boca Raton, FL, USA.
Pereira, L.S., Oweis, T. & Zairi, A. (2002). Irrigation management under water scarcity. Agricultural Water Management, 57, 175–206. https://doi.org/ 10.1016/S0378-3774(02)00075-6.
Scarano, F. (2013). Tomographic PIV: principles and practice. Measurement Science and Technology, 24, 012001. https://doi.org/10.1088/09570233/24/1/ 012001.
Siebert, S., Burke, J., Faures, J.M., Frenken, K. & Portmann, F.T. (2010). Groundwater use for irrigation–a global inventory. Hydrology and Earth System Sciences Discussions, 7. https://doi.org/ 10.5194/hess-14-1863-2010.
Yoo, M.W., Kim, Y.D. & Lyu, S. (2009). Flowrate and velocity measurement in Nakdong River using ADCP. In: Advances in Water Resources and Hydraulic Engineering, pp. 1946–1949. Springer, Berlin/Heidelberg, Germany. https://doi.org/ 10.1007/978-3-540-89465-0_333.
Xiaoping, H. & Ahuja, N. (1993). Motion and structure estimation using long sequence motion models. Image and Vision Computing, 11, 549–569. https://doi.org/10.1016/02628856(93)90021-8.

  • Receive Date 06 May 2025
  • Revise Date 09 September 2025
  • Accept Date 18 October 2025