Site effect evaluation using spectral ratios with only one station

Abstract

The spectral ratio technique is a common useful way to estimate empirical transfer function to evaluates site effects in regions of moderate to high seismicity. The purpose of this paper is to show that it is possible to estimate empirical transfer function using spectral ratios between horizontal and vertical components of motion without a reference station. The technique, originally proposed by Nakamura to analyze Rayleigh waves in the microtremor records, is presented briefly and it is discussed why it may be applicable to study the intense S-wave part in earthquake records. Results are presented for three different cities in Mexico: Oaxaca, Oax., Acapulco, Gro., and Mexico City. These cities are very different by their geological and tectonic contexts and also by the very different epicentral distances to the main seismogenic zones affecting each city. Each time we compare the results of Nakamura's technique with standard spectral ratios. In all three cases the results are very encouraging. We conclude that, if site effects are caused by simple geology, a first estimate of dominant period and local amplification level can be obtained using records of only one station.

A Stochastic Method for Simulating Near‐Field Seismograms: Application to the 2016 Tottori Earthquake

“…For soft soil sites, the local site effect should also be considered. It is known that the rough estimation of the soil amplifications can be calculated by using H/V spectral ratio approach (Ameri et al, 2011;Castro et al, 1997;Field & Jacob, 1995;Ji, 2014;Lermo & Chávez-García, 1993, 1999Yalcinkaya et al, 2012). For general sites, as there is no obvious amplification phenomenon of vertical ground motion in the horizontal amplification frequency band (Castro et al, 1997), the amplification characteristics of Note.…”

Comparison of the Dynamic and Static Corner Frequencies in Ground Motion Simulation: Cases Study of Jiuzhaigou Earthquake and Northridge Earthquake

“…paper, the windowing function proposed by Konno and Ohmachi (1998) was employed for smoothing the obtained Fourier spectrum in a range of 0.5 and 15 Hz, while the smoothing constant was taken as 20 (Sun et al, 2013;Fu and Li, 2017;Kkallas et al, 2018). In our applications, we adopt the κ 0 filter in the form of κ 0.033036 + 0.0008401×R, as shown in Figure 2, and employed the H/V spectral ratio approach (Lermo and Chávez-García, 1993) to estimate the local site amplification in the Jiuzhaigou earthquake .…”

An Early-Warning System to Validate the Soil Profile during TBM Tunnelling

“…From the mid-1900s, thanks to systematic measurements of microtremors, it was found that the properties of the ground as inferred from the characteristics of these microtremors can be used to determine the seismic factor related to earthquake-proof construction designs [72,73]. The HVSR technique for microtremor studies has gained much popularity over the past years [37,[74][75][76].…”