Published on 23 February 2019
The Northern Caucasus that is characterized by moderate seismic activity refers to areas with high seismic hazard potential. In the process of investigation the Kolka glacier in 2002, it was found that the maximum earthquake effect for example in the mountainous regions of North Ossetia was reaching 10–11 points. Analysis of instrumental data shows that even within the same region, the intensity, duration, and predominant period of oscillations may vary. Moreover, it was later found out that the fault in the southern part of the city of Vladikavkaz, the capital of the Republic of North Ossetia-Alania, can be a source of a strong earthquake with a maximum expected magnitude of M = 7.1, which can form 9-10 points intensity values directly in densely populated city. This circumstance should be taken into account in seismic design and practical construction. Seismic safety is the basis for the sustainable development of mountain areas. In conditions of moderate seismic activity, when there are practically no records of strong motions in the area of interest, different models of generating synthetic accelerograms are used. One of the methods is a stochastic one based on probabilistic models taking into account regional features of earthquake sources. To simulate the effects, a quasi-stationary or amplitude-nonstationary model is used. Components of the seismic action are represented as a product of a stationary random function and a deterministic envelope. Synthetic accelerograms were obtained for the most dangerous for the territory of the city of Vladikavkaz city seismic zones. Curves of the dynamicity coefficient and the corresponding envelope were constructed, taking into account the particular locations of the sources of possible earthquakes on the investigated territory, accounting for which will increase the safety of the population. In the interval of periods T = 0.1–0.4 s expected seismic effect is 1.6 times higher than the standard curve of the dynamic coefficient. for average values, the excess is 1.3, in the interval of periods T = 0.4–2.0, the calculated maximum values are within the calculated curve. For the first time, a regional dynamic curve was obtained which can be successfully used in earthquake-proof design and practical construction.
Categories: Articles, Geo-ecological,-Recreational-and-Biomedical-Issues-of-SDMT
Tags: сейсмические воздействия, акселерограмма, стохастический метод, коэффициент динамичности
ISSN 1998-4502 (Print) ISSN 2499-975Х (Online)