scholarly journals ON THE OVERLAND FLOW OF TSUNAMI AND EFFECTIVENESS OF WALL AS A COUNTER MEASURE

1968 ◽  
Vol 1 (11) ◽  
pp. 58 ◽  
Author(s):  
Toshio Iwasaki ◽  
Hiroyoshi Togashi
Keyword(s):  
Overland Flow ◽  
Vertical Wall ◽  
Large Magnitude ◽  
Populated Area ◽  
Running Water ◽  
Tsunami Waves ◽  
Public Investments ◽  
Sloping Beach ◽  
Theoretical Results ◽  
Horizontal Area

When a tsunami of large magnitude strikes a coast line, various kinds of disaster such as loss of lives, properties or public investments are caused by inundation of tsunami over nearly horizontal area. Although tsunami runup has been investigated for the sloping beach, these populated area is bordered on sea by a vertical wall such as a quaywall or a highway revetment. In this paper, transformation of tsunami waves at a vertical quaywall is analysed using U-C characteristics and overland flow is treated. Effectiveness of a vertical land dike aiming to stop running water is investigated also. Theoretical results are verified by experiments.

STEEP STANDING WAVES AGAINST A VERTICAL WALL ON A SLOPING BEACH

2011 ◽  
pp. 1762-1769
Author(s):  
W. KIOKA ◽  
T. KITANO ◽  
M. OKAJIMA ◽  
N. MIYABE
Keyword(s):  
Vertical Wall ◽  
Standing Waves ◽  
Sloping Beach

scholarly journals Numerical Investigations of Tsunami Run-Up and Flow Structure on Coastal Vegetated Beaches

Water ◽  
2018 ◽  
Vol 10 (12) ◽  
pp. 1776 ◽  
Author(s):  
Hongxing Zhang ◽  
Mingliang Zhang ◽  
Tianping Xu ◽  
Jun Tang
Keyword(s):  
Wave Propagation ◽  
Numerical Model ◽  
Peak Flow ◽  
Tsunami Wave ◽  
Coastal Vegetation ◽  
Coastal Forest ◽  
Governing Equations ◽  
Tsunami Waves ◽  
Run Up ◽  
Sloping Beach

Tsunami waves become hazardous when they reach the coast. In South and Southeast Asian countries, coastal forest is widely utilized as a natural approach to mitigate tsunami damage. In this study, a depth-integrated numerical model was established to simulate wave propagation in a coastal region with and without forest cover. This numerical model was based on a finite volume Roe-type scheme, and was developed to solve the governing equations with the option of treating either a wet or dry wave front boundary. The governing equations were modified by adding a drag force term caused by vegetation. First, the model was validated for the case of solitary wave (breaking and non-breaking) run-up and run-down on a sloping beach, and long periodic wave propagation was investigated on a partially vegetated beach. The simulated results agree well with the measured data. Further, tsunami wave propagation on an actual-scale slope covered by coastal forest Pandanus odoratissimus (P. odoratissimus) and Casuarina equisetifolia (C. equisetifolia) was simulated to elucidate the influence of vegetation on tsunami mitigation with a different forest open gap. The numerical results revealed that coastal vegetation on sloping beach has significant potential to mitigate the impacts from tsunami waves by acting as a buffer zone. Coastal vegetation with open gaps causes the peak flow velocity at the exit of the gap to increase, and reduces the peak flow velocity behind the forest. Compared to a forest with open gaps in a linear arrangement, specific arrangements of gaps in the forest can increase the energy attenuation from tsunami wave. The results also showed that different cost-effective natural strategies in varying forest parameters including vegetation collocations, densities, and growth stages had significant impacts in reducing the severity of tsunami damage.

Experimental Investigation of Tsunami Bore Forces on Vertical Walls

2013 ◽  
Vol 135 (2) ◽  
Author(s):  
I. N. Robertson ◽  
K. Paczkowski ◽  
H. R. Riggs ◽  
A. Mohamed
Keyword(s):  
Vertical Wall ◽  
State University ◽  
Flat Bottom ◽  
Large Wave ◽  
Wave Flume ◽  
Pressure Distributions ◽  
Vertical Walls ◽  
Series Of Experiments ◽  
Maximum Impact Force ◽  
Sloping Beach

A series of experiments have been carried out in the large wave flume (LWF) at Oregon State University to quantify tsunami bore forces on structures. These tests included “offshore” solitary waves, with heights up to 1.3 m, that traveled over a flat bottom, up a sloping beach, and breaking onto a flat reef. Standing water depths on the reef varied from 0.05 m to 0.3 m. Resulting bores on the reef measured up to approximately 0.8 m. After propagating along the reef, the bores struck a vertical wall. The resulting forces and pressures on the wall were measured. The test setup in the LWF is described, and the experimental results are reported. The results include forces and pressure distributions. Results show that the bores propagated with a Froude number of approximately 2 and that the forces follow Froude scaling. Finally, a design formula for the maximum impact force is given. The formula is shown to be an improvement over existing formulas found in the literature.

Runup of tsunami waves on a vertical wall in a basin of complex topography

1999 ◽  
Vol 24 (5) ◽  
pp. 431-436 ◽  
Author(s):  
E. Peilnovsky ◽  
E. Troshina ◽  
V. Golinko ◽  
N. Osipenko ◽  
N. Petrukhin
Keyword(s):  
Vertical Wall ◽  
Complex Topography ◽  
Tsunami Waves

scholarly journals COMPUTER AID FOR OPTIMUM DESIGN OF TSUNAMI WAVES

1974 ◽  
Vol 1 (14) ◽  
pp. 37
Author(s):  
Toshio Iwasaki
Keyword(s):  
Boundary Conditions ◽  
Continental Shelf ◽  
Optimum Design ◽  
Dynamic Process ◽  
Southern Coast ◽  
Large Magnitude ◽  
Sanriku Coast ◽  
Tsunami Waves ◽  
Statistical Results ◽  
Dispersive Nature

The tsunami process of their generation and propagation to the near-coast offshore region is discussed. Purpose is to give optimum configurations of tsunami waves of large magnitude, which can be used as boundary conditions for the analysis of the dynamic process near the shore or around structures in coastal zone. They are obtained by numerical computations along the southern coast of the Hokkaido and the Sanriku Coast for various tsunami sources set on the continental shelf facing to the Japan Submarine Trench. Dispersive nature of the tsunamis seems to make the problem very complicated. However statistical results thus obtained can be accepted for the base of design of structures.

scholarly journals NUMERICAL ANALYSES ON PROPAGATION OF NONLINEAR INTERNAL WAVES

2011 ◽  
Vol 1 (32) ◽  
pp. 24
Author(s):  
Kei Yamashita ◽  
Taro Kakinuma ◽  
Keisuke Nakayama
Keyword(s):  
Internal Wave ◽  
Internal Waves ◽  
Wave Breaking ◽  
Wave Equations ◽  
Vertical Wall ◽  
Submerged Breakwater ◽  
Wave Trough ◽  
Water Region ◽  
Wave Nonlinearity ◽  
Sloping Beach

A set of nonlinear surface/internal-wave equations, which have been derived on the basis of the variational principle without any assumptions concerning wave nonlinearity and dispersion, is applied to compare numerical results with experimental data of surface/internal waves propagating through a shallow- or a deep-water region in a tank. Internal waves propagating over a submerged breakwater or a uniformly sloping beach are also simulated. The internal progressive wave shows remarkable shoaling when the interface reaches the critical level, after which physical variables including wave celerity become unstable near the wave-breaking point. In the case of the internal-wave trough reflecting at the vertical wall, the vertical velocities of water particles in the vicinity of the interface are different from that of the moving interface at the wall near the wave breaking, which means that the kinematic boundary condition on the interface of trough has been unsatisfied.

Sign in / Sign up

Export Citation Format

Share Document