Simplified formulae for designing coastal forest against tsunami run-up: one-dimensional approach
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In the present study, laboratory experiments were conducted to validate the applicability of a numerical model based on one-dimensional nonlinear long-wave equations. The model includes drag and inertia resistance of trees to tsunami flow and porosity between trees and a simplified forest in a wave channel. It was confirmed that the water surface elevation and flow velocity by the numerical simulations agree well with the experimental results for various forest conditions of width and tree density. Further, the numerical model was applied to prototype conditions of a coastal forest of Pandanus odoratissimus to investigate the effects of forest conditions (width and tree density) and incident tsunami conditions (period and height) on run-up height and potential tsunami force. The modeling results were represented in curve-fit equations with the aim of providing simplified formulae for designing coastal forest against tsunamis. The run-up height and potential tsunami forces calculated by the curve-fit formulae and the numerical model agreed within ± 10% error.
KeywordsTsunami run-up Coastal forest Pandanus odoratissimus Tsunami force
This research is funded by Vietnam National Foundation for Science and Technology Development (NAFOSTED) under Grant Number 105.06-2017.07 (numerical method), and partially funded by Ministry of Science and Technology under grant number ĐTĐL-C.35/15 (long wave like abnormal water level), to which the authors are gratefully acknowledged.
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