Specifics of seismicity manifestations in the construction area of olympic games engineering structures in Imeretinskaya Depression, Sochi

Abstract

Geological and geotechnical conditions in Imeretinskaya Depression, where Olympic Game facilities will be constructed, have some features not typical of other parts of the Great Sochi. These include the large thickness (up to 70–100 m) of Quaternary marine and alluvial deposits, overlying half-rocks and hard rocks, as well as a wide occurrence of soils of II–III and III category in terms of seismic properties. These factors, along with the high seismicity of the area, require one who determines the quantitative characteristics of seismic impacts, to take into account both the features of geological structure and properties of soils and the effect of both nearby and relatively remote earthquake sources on the magnitude and the frequency content of vibrations. Two geotechnically unfavorable sections within Imeretinskaya depression with poor data on the seismic properties of rocks throughout the depth of the Quaternary strata are used as examples to demonstrate the methodological approaches to evaluating the characteristics of seismic impacts. In conclusion, proposals regarding experimental verification of the obtained results are formulated and recommendations are given regarding the improvement of the properties of foundation soils on which earthquake induced accelerations under natural conditions reach 300–450 cm/s2.