Analytical Review of Classifications of Soil Conditions and Response Spectra in Foreign Buiding Codes for Earthquake-Resistant Construction for Developing Standardization in the Russian Federation

Abstract

The article presents a brief overview of soil classifications and response spectra adopted in the building codes of the European Union and 15 other countries possessing seismically active regions, such as the United States, Japan, Australia and New Zealand, South Africa, Turkey, Iran, Kazakhstan, Kyrgyzstan, Armenia, Azerbaijan, Ukraine, Uzbekistan, Saudi Arabia, and China. The descriptions are based on regulatory documents, commentaries on standards, and scientific publications. The review indicated that classification of soil conditions and descriptions of response spectra in the Russian building codes SP14.13330.2018 significantly lag behind their foreign counterparts and do not provide necessary reliability of seismic motion assessments; also, an unreasonably wide range of S-wave velocities is defined for soils of category 2. To improve the situation, we suggest the following: (1) increase the number of soil categories in the building codes of Russian Federation to five main categories, including the category of soils with resonance properties, and two additional categories that require special investigations, and balance the ranges of S-wave velocities; (2) define two groups of response spectra for the main types of soils, for stronger and weaker earthquakes, as done in the Eurocodes; (3) include determination of predominant periods of vibrations of soil strata in studies of site conditions; (4) introduce corrections for topographic effects during construction in mountainous areas. These adjustments will not require substantial efforts, but will lead to a significant increase in the reliability of seismic motion assessments.