About the Group
Based on the observations during the 2004 Indian Ocean tsunamis, it is evident that the leading tsunami waves could have various forms: undulating bores and long waves with a leading depression. It is certain that theses leading waves are not solitary waves. A new paradigm needs to be established for experimental tsunami research.
As tsunamis inundated and flooded the land, they often left behind widespread sediment deposits. If the properties of tsunami deposits can be correlated with the flow depth, velocity, and wave characteristics of tsunamis, the dated deposits will allow estimates of times and recurrence intervals of past tsunamis. Since the sediment transport processes are primarily driven by the flow turbulence and bed shear stresses, it is essential to have an in-depth understanding on the evolution of near bed flows driven by the leading waves of tsunamis, in particular the bed shear stress.
Responding to the research needs mentioned above, we will conduct the following research activities: -Developing and implementing algorithms for the new wave maker at the large wave flume at Oregon State University so that different types of leading tsunami wave forms, including bores and N- waves can be simulated in the NEES tsunami facilities; -Measuring and analyzing runup heights of various leading tsunami wave forms on a plane beach; -Design and install a new instrument package for measuring bed shear stress in the NEES facilities; -Measuring and analyzing bottom shear stress under various leading tsunami wave form.
The proposed research is a part of a long term fundamental research program, aiming at correlating the tsunami hydrodynamics with the tsunami sediment deposits. The experimental data, obtained from the project, will provide the necessary information for parameterizing wave breaking, bottom shear stress and flow turbulence in the sediment suspension and transport models. Therefore, the proposed research will have a much broader impact on the establishment of tsunami hazard mitigation programs.