Examination of Earthquake Intensity Increments on Side-Zones of Valleys within Alluvial Basins by an Analytical Approach

Yıl 2020, Cilt: 6 Sayı: 1, 1 - 11, 11.05.2020

Ahmet Hakan Mutlu

Öz

The effect of topography
on the seismic wave-motion has been of interest to many studies. In this study,
the earthquake-intensity increments (amplification) on side-zones of valleys within
alluvial basins, were investigated using finite element method. A set of finite
element models for valleys, one with a triangular cross-section, and the rest
with trapezoidal cross-sections, taking into account five different side slopes
(17º, 22º, 27º, 37º, 45º), were adapted. The acceleration time-histories
obtained through the use of the commercial finite element code (QUAD4M) at
valley-sides, valley-edges, and at the intermediate points were transformed to
Fourier Amplitude Spectra. The amplitude-frequency variations obtained at the
three selected reference points of the valley as well as at the bedrock, were
investigated in each of the four selected phases of the earthquake duration. As
a result of the performed dynamic analysis, the effect of the valley-slope
variation at the three reference points on the valley was examined at four distinct
phases of the earthquake duration.

Anahtar Kelimeler

Effects of topography, slope of valley, seismic reflection

Kaynakça

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