The paper discusses methods and approaches used in Russia and abroad for mapping tsunami hazard on the coasts affected by tsunami waves that is for solving the problem of the preliminary tsunamizonation of the coast. This task consists in obtaining estimates of the tsunami heights on the coast with a given probability of exceedence during a certain time interval. Currently, this problem is being solved based on constructing seismotectonic models of the main tsunamigenic zones threatening a particular coast as well as numerical models of tsunami generation and propagation in the ocean with a real bathymetry to create a computed catalog of wave heights on the coast. The methodological commonality of this problem with the problem of seismic zonation of coastal territories is noted. The latter is solved now in all countries on the basis of the methodology of the Probabilistic Seismic Hazard Assessment. A similar methodology for tsunamizonation is called Probabilistic Tsunami Hazard Assessment. With all known shortcomings of this technique, both fundamental and technical, it can and should be used for mapping of tsunami hazard on the coasts of Russia. The problems of rational choice of the scale of tsunami hazard maps, selection of a set of charted parameters, and the problem of estimating the maximum possible event are discussed.

The information concerning the most essential tsunami events on the Russian Pacific coast is given. Methods of the quantitative estimates of the tsunami hazard and its historical developing are described. A short sketch on the logic chain hazard-vulnerability-risk is given. The parameters describing tsunami hazard are considered. A short survey on the quatitative estimates of the fatalities and damages is given. Probabilistic model of the Poissonian type for the tsunami sequence on the Far Eastern coast of the Russia is created. Some general problems related to the probabilistic approach to tsunami hazard estimation are also considered. The parameters of this model were determined and their physical meaning is explained. Correct method for the quantitative evaluation of these parameters using observational data of historical tsunamis is created. Process of the tsunami run-up is considered especially. For one-dimentional run-up, some relationships between the maximal (minimal) delevelling and maximal current velocity and horizontal coordinate are created. The problem of the run-up accompanied by wave breaking is described shortly. On the basement of the probabilistic model, some analytical formulae for the quantitative estimates of the tsunami hazard are proposed. Some variants of parameters for tsunami hazard maps are considered. An example of the tsunami hazard map in terms of h₁₀₀ for the coast of the Southern Kuril Islands is given.

The subject of this study is to estimate how the quality of bottom bathymetry data effects on the capability of the numerical models to adequately reproduce the distribution of the maximum heights of tsunami waves along the coast. Numerical experiments have been carried out for the Simushir tsunamis of November 15, 2006 and January 13, 2007 in the Central Kuril region. It is shown that widely used bathymetry data bases, such as GEBCO, do not provide the required accuracy and resolution of digital bathymetry charts. Here we have used various data sources, including GEBCO in the deep ocean region and data from the GUNIO on the shelf and in the shallow waters. It is shown that the calculations performed for grids with a resolution of 30 arc seconds provide only a qualitative estimate of the distribution of tsunami heights along the coast. At the same time, a quantitative coincidence of the simulation results and the observational data can be obtained only for grids with a spatial resolution of 10 arc seconds or better. The maximum tsunami heights were observed along the coast of Isle Matua, which is confirmed by the model calculations. Detailed studies have shown that the extreme tsunami heights and current velocities are observed in the Dvoynaia Bay (Matua Island) and are associated with the occurrence of eigenmodes oscillations in the bay.

Tsunamis in shallow water zones lead to sea water level rise and fall, strong currents, forces (drag, impact, uplift, etc.), morphological changes (erosion, deposition), dynamic water pressure, as well as resonant oscillations. As a result, ground materials under the tsunami motion move, and scour/erosion/deposition patterns can be observed in the region. Ports and harbors as enclosed basins are the main examples of coastal structures that usually encounter natural hazards with small or huge damaging scales. Morphological changes are one of the important phenomena in the basins under short and long wave attack. Tsunamis as long waves lead to sedimentation in the basins, and therefore, in this study, the relation to the current pattern is noticed to determine sedimentation modes. Accordingly, we present a methodology based on the computation of the instantaneous Rouse number to investigate the tsunami motion and to calculate the respective sedimentation. This study aims to investigate the effects of the incident wave period on an L-type harbor sedimentation with a flat bathymetry using a numerical tool, NAMI DANCE, which solves non-linear shallow water equations. The results showed that the corner points on the bending part of the basin are always the critical points where water surface elevation and current velocity amplify in the exterior and interior corners, respectively. This phenomenon is more obvious in wave amplification. Comparing the maximum current velocity results with the minimum Rouse number results, one can conclude that the pattern of sediment motion in the mentioned two critical corner points and in the whole basin depends on both the current pattern and magnitude. In large wave periods, the sediment motion in the exterior corner (Gauge 63) is often in the bed load form, while in the interior corner (Gauge 57) in the wash load form. This indicates that, in higher periods, the interior and exterior corners can be exposed to the sediment erosion and deposition, respectively. However, sediment motion in long wave conditions needs further analysis in closed basins, where it becomes a prominent problem for harbors and ports. Further studies on sediment motion seem necessary to determine the performance and validity of NLSWE when the volume of the transmitted sediments needs to be measured under the current behavior of the long waves. Furthermore, more investigations should be performed to analyze the behavior of L-type basins with varying depths and then applied to real harbors of this type.

Tsunamis are high-impact, long-lasting disasters, which in most cases allow for only a few minutes of warning before impact. The amount of energy behind huge tsunami waves can cause severe destruction when it hits land and consequently causes massive loss of human life. The impact of tsunami can be considered in social, environmental, and economic dimensions. The social impact can be seen in destruction of life and property, health crisis and disease. Tsunamis may cause massive environmentally impact by devastating effects. In this paper, the impact of 2004 and 2011 tsunamis on coasts and constructions are evaluated from the engineeering perspective. Discussions with suggestions are presented.

Tsunami research is a very complex applied problem. Even a partial solution of this problem will significantly mitigate catastrophic destruction and reduce the number of human casualties after this natural phenomenon. In the process of tsunami studying physical modeling often provides the additional information for numerical simulation. First of all, this is the information about the interaction of tsunamis with the complex design constructions and possible destruction of these constructions. Such information is, in principle, can be obtained using a CFD simulation method. However, CFD model also requires verification by the laboratory data. There are many ways to conduct tsunami simulation and many methods of tsunami wave generation. The most widespread and studied way of wave generation is moving block method. The method of wave generation using special wave paddles or shields is also used. In recent times, a fundamentally new way of tsunami simulating was developed. New pneumatic tsunami generator consists of a tank with water and vacuum pump. Each of the methods has its advantages and disadvantages.

In theoretical and experimental researches of loads from a collapsed wave on marine and coastal structures from tsunami dynamic effect due to the flexibility of the structure and the foundation was not taken. The generalized dependence of the resultant pressure waves of the collapsed wave (bore) from time was established based on the analysis of modern publications. The reaction of structures to the effects of bore depends of loading and stiffness of the system «soil-construction». Numerical evaluation of dynamic effects for different values of the loading rate and the stiffness of the system, for example, of protective breakwater are made. Various ground bases corresponding to possible conditions of construction are examined. As the analyses scheme of the building there was considered an absolutely rigid body on an elastic base with two degrees of freedom — displacement in the horizontal direction and rotation in the plane perpendicular to the axis of the pier. Self-oscillations corresponding to the lower mode taking into account the inertial effects of water are considered. From the results of the article, researches have shown that, when defining loads from the bore on the protection structure should take into account their dynamic nature. For a conservative evaluation in approximate calculations it is allowed to take the value of the dynamic factor equal to two.

A History of the tsunami safety problem on the sea coasts of Russia and of tsunami design code development are described. The code "Buildings and structures on tsunami hazardous areas. Regulations of design" is developed by the working group of "Regional Alliance for Disaster Analysis & Reduction" NPO on behalf of the President of the Russian Federation 18.05.2015 and appropriate decisions of the Government Russia from 28.09.2015 and from 04.08.2016. The Code consists of 12 chapters and 7 appendices. The code of rules developed for the first time should be applied when designing new construction and reconstruction of existing on-shore and Marinas buildings and structures in order to ensure their normalized reliability and safety under tsunami impact. The new basic terms and definitions that are unified and aligned with the terminology used by oceanographers, civil engineers and specialists of EMERCOM are introduced. Conceptual approaches, conditions, assumptions and understandings adopted as basic are given. Much attention is paid to the requirements imposed on the initial data, which is necessary for design, and especially, to assign tsunami hazard, which can be performed in various ways. The tsunami hazardous areas are classified by the intensity of the estimated tsunami, proximity to the tsunamigenic earthquake focus, the possibility of evacuating people and other parameters. Constructed facilities are subdivided according to their significance for life support and emergency management. Analytical calculation and design of tsunami resistance and the serviceability of only certain buildings and structures (life facilities, objects — sources of secondary danger, difficultly evacuated objects, etc.) are necessary and described in detail. It is emphasized that the main task of tsunami safety is to minimize individual risk, i.e. risk associated with the life and health of people. Thus, tsunami hazardous area as a whole (not single building) is a key object of standardization. Urban planning and engineering aspects for the tsunami disaster reduction are presented. The methodology, tools and mathematical apparatus for analysis and control of tsunami-risk, well-tested previously to ensure seismic safety, were used in the code of rules. The conclusion provides an overview of the results, criticisms and suggestions for further research.