INVESTIGATION OF INFLUENCE OF THE LOCAL GROUND CONDITIONS O N THE SEISMIC HAZARD OF A CONSTRUCTION SITE

Abstract

When studying seismic hazard, it is necessary to evaluate the local effect of earthquakes.
The main factors that determine the parameters of surface vibrations during earthquakes include local
effects associated with the response of the soil, the effects of surface topography and the topography
of internal boundaries (heterogeneities, inclusions, sedimentary basins, etc.). At present, methods for
reliable estimation of these effects have been developed in seismology. Knowledge of the probabilistic
parameters of surface vibrations is necessary to calculate the reaction spectra, dynamic stresses and
deformations that can cause destruction of buildings, to assess the possibility of soil liquefaction. The
article examines the influence of local soil conditions on the seismicity of a construction site during an
earthquake. To assess the seismic stability of structures erected on a layered foundation, it is necessary
to investigate the influence of local soil conditions on surface vibrations during an earthquake. The
influence of local soil conditions on the change in the characteristics of vibrations of the surface of the
construction site of a structure during an earthquake is the result of a complex process of the passage
of seismic waves. The resulting seismic effect of the construction site is affected by the parameters of
the initial seismic load and the characteristics of the soil layers underlying the base. Under certain
ground conditions, dynamic amplification or attenuation can occur in the form of a change in the
amount of peak acceleration or the duration of oscillations. The layers of the underlying soil are capable
of changing the frequency characteristics of the oscillations of the seismic wave coming to them. The
result of such changes may be an increase in oscillations in certain frequency ranges, which may
coincide with the natural frequencies of the erected structure, which leads to resonance effects.