Response spectrum method for spatial seismic ground motion

Abstract

For seismic analysis of wide structures (for example, airports, stadiums, bridges, etc.), it is important to consider the wave seismic motion of the ground with spatial variability. The differential seismic motion is described by the vector field of kinematic parameters at each point of the base. The differential model of seismic excitation is used for structures on a flexible foundation or discrete supports, if the short-length waves (compared to the size of the foundation) are dominated in seismic waves spectrum. Such excitation is accompanied by angular displacements due to uneven translational ground motions, and it is not yet possible to consider using standard seismic analysis. This paper presents a method of differential seismic analysis with the corresponding modification of the response spectrum (RSM) method. The proposed method requires three accelerograms at each reference point. These accelerograms can be obtained during detailed seismic zoning. To illustrate the method, a model of a stadium cover is considered, for which it is important to apply a spatial differential seismic excitation, and some properties of the excitation are described and analyzed.

Digital modeling of seismic impact on the frame of multi-storey buildings with outrigger systems

“…All structures are made of monolithic reinforced concrete. Slab grillage, floor and roof slabs, walls and diaphragms for seismic effects were modeled by triangular shell elements with 18 degrees of freedom and quadrangular shell elements with 24 degrees of freedom [5]. The columns were modeled by spatial rods with 12 degrees of freedom.…”