The effect of dynamic amplification due to a structure׳s vibration on breaking wave impact. (1st March 2015)

• Record Type: Journal Article
• Authors: Choi, Sung-Jin; Lee, Kwang-Ho; Gudmestad, Ove Tobias
• Is Part Of: Ocean engineering. Volume 96(2015)
• Page Start: 8
• Page End: 20
• Publication Date: 2015-03-01
• Subjects: Breaking wave impact force -- Dynamic amplification factor -- Low pass filter -- EMD -- Duhamel integral; Ocean engineering -- Periodicals; Ocean engineering; Periodicals; 620.4162
• DOI: 10.1016/j.oceaneng.2014.11.012
• Languages: English
• ISSNs: 0029-8018

Abstract

Abstract: In this paper, breaking wave impact forces on vertical and inclined piles are studied by using a 3D numerical model. A method for obtaining net breaking wave impact forces from the measured response time history is also investigated. The computed forces are compared with the results of hydraulic model tests. However, because the piles installed in the numerical model are modeled as rigid objects, it is not possible to make a direct comparison between the CFD (Computational Fluid Dynamic) results and the experimental data. A force separation procedure is used for the experimental data. A low pass filter and EMD (Empirical Mode Decomposition) are employed for removing the effect of dynamic amplification in the experimental data, and the filtered results are compared with the numerical results. Based on the results, DAFs (Dynamic Amplification Factor) are estimated for these particular structures. Moreover, Duhamel integral is used to reproduce dynamic breaking wave forces (i.e., net breaking wave force+the force which is the amplified component due to the structure׳s vibration) based on the breaking wave forces calculated by the CFD model. The reproduced results are compared with the unfiltered experimental data for the verification of the method stated above. Highlights: A CFD model is employed to estimate breaking wave forces on cylindrical piles. A low pass filter and EMD are used to remove dynamic amplification in measured data. The filtered results (EXP.) compare well with the CFD results. Duhamel integral is used to reproduce dynamic responses based on CFD results. The reproduced results are compared with the unfiltered results for the verification.