Analysis of Ground Motion Amplification during Soil Liquefaction via Nonstationary Fourier Spectra

abstract Due to inertial and damping characteristics of strong motion seismographs, recorded ground motion accelerograms may in some cases be sufficiently in error to significantly affect the results obtained when generating standard response or Fourier spectra. Therefore, the objectives of this paper are to present an analytical method of generating standard spectra which will eliminate the above instrumental error and to show the significance of this error by presenting some sample results obtained from accelerograms representing both earthquakes and underground nuclear explosions.

Download Full-text

Scaling of Fourier Spectra of strong earthquake ground motion in western Himalaya and northeastern India

Soil Dynamics and Earthquake Engineering ◽

10.1016/j.soildyn.2017.08.010 ◽

2017 ◽

Vol 102 ◽

pp. 137-159 ◽

Cited By ~ 9

Author(s):

I.D. Gupta ◽

M.D. Trifunac

Keyword(s):

Ground Motion ◽

Strong Earthquake ◽

Western Himalaya ◽

Earthquake Ground Motion ◽

Northeastern India ◽

Fourier Spectra

Download Full-text

Ground-motion amplification at the Colle di Roio ridge, central Italy: a combined effect of stratigraphy and topography

Geophysical Journal International ◽

10.1093/gji/ggw120 ◽

2016 ◽

Vol 206 (1) ◽

pp. 1-18 ◽

Cited By ~ 20

Author(s):

S. Hailemikael ◽

L. Lenti ◽

S. Martino ◽

A. Paciello ◽

D. Rossi ◽

...

Keyword(s):

Ground Motion ◽

Central Italy ◽

Combined Effect ◽

Ground Motion Amplification

Download Full-text

Geophysical and geotechnical factors in urban planing: Bursa (Nilüfer, Osmangazi, and Yildirim) cases

10.5194/nhess-2020-301 ◽

2020 ◽

Author(s):

Ferhat Özçep ◽

Guldane Boyraz ◽

Okan Tezel ◽

Hakan Alp ◽

Nuray Alpaslan ◽

...

Keyword(s):

Ground Motion ◽

Hazard Analysis ◽

Earthquake Hazard ◽

Cyclic Stress ◽

Soil Liquefaction ◽

Wave Velocities ◽

Shear Wave Velocities ◽

Earthquake Motion ◽

Potential Index ◽

Earthquake Hazard Analysis

Abstract. The study area covers the Central of Bursa, Osmangazi, Yildirim, Gürsü, Kestel and Nilüfer District boundaries in Bursa. The seismic process deals with the occurrence of an earthquake event and the process of wave propagation from the source to the site. Local amplification caused by surficial soft soils is a significant factor in destructive earthquake motion. In the first phase of this study, it is investigated the ground motion level and soil amplifications for Bursa city. For his aim, probabilistic and deterministic earthquake hazard analysis (including acceleration estimations) will be carried out for the region. Local amplification caused by surficial soft soils is a significant factor in destructive earthquake motion. In the first phase of this study, it is investigated the ground motion level and soil acharacterization for the region. For his aim, probabilistic earthquake hazard analysis (including acceleration estimations) was carried out for the region. Then, soil shear wave velocities were estimated from data obtained by MASW measurements. Soil liquefaction is a natural event in which the strength and stiffness of a soil are reduced by earthquake vibrations or other dynamic loadings. As it is known, liquefaction occurs in saturated soils, that is, soils in which the space between individual particles is completely filled with water. One of liquefaction evaluation methods is based on the cyclic stress approach. In this method, a safety factor is defined as CRR/CSR. CRR is a cyclic resistance ratio that represents soil liquefaction susceptibility, and CSR is the cyclic stress ratio that represents the earthquake effect. In the second phase of this study, possible soil potential index (PL) and ground induced settlements were estimated by using Isihara ve Yoshimine (1990) approach. All results on liquefaction potential index (Pl), liquefaction induced settlements and soil shear wave velocities in Bursa (Turkey) City were compared with each other. Finally, a seismic microzonation map was prepared by the integration of geophysical and geotechnical data for urban planning purposes.

Download Full-text

Near-Surface Seismic Studies To Estimate Potential Earthquake Ground Motion Amplification At A Thick Soil Site In The Ottawa River Valley, Canada

10.3997/2214-4609-pdb.192.ssi_6 ◽

2001 ◽

Author(s):

Beatriz Benjumea ◽

Jim A. Hunter ◽

Susan E. Pullan ◽

Robert A. Burns ◽

Ron L. Good

Keyword(s):

Ground Motion ◽

River Valley ◽

Earthquake Ground Motion ◽

Near Surface ◽

Ground Motion Amplification ◽

Ottawa River ◽

Soil Site

Download Full-text

Physical stratigraphy and geotechnical properties controlling the local seismic response in explosive volcanic settings: the Stracciacappa maar (central Italy)

Bulletin of Engineering Geology and the Environment ◽

10.1007/s10064-020-01925-5 ◽

2020 ◽

Vol 80 (1) ◽

pp. 179-199

Author(s):

M. Moscatelli ◽

G. Vignaroli ◽

A. Pagliaroli ◽

R. Razzano ◽

A. Avalle ◽

...

Keyword(s):

Seismic Response ◽

Ground Motion ◽

Central Italy ◽

Volcanic Event ◽

Ground Motion Amplification ◽

Local Seismic Response ◽

Single Station ◽

Seismic Scenarios ◽

Physical Stratigraphy ◽

Subsoil Model

AbstractNowadays, policies addressed to prevention and mitigation of seismic risk need a consolidated methodology finalised to the assessment of local seismic response in explosive volcanic settings. The quantitative reconstruction of the subsoil model provides a key instrument to understand how the geometry and the internal architecture of outcropping and buried geological units have influence on the propagation of seismic waves. On this regard, we present a multidisciplinary approach in the test area of the Stracciacappa maar (Sabatini Volcanic District, central Italy), with the aim to reconstruct its physical stratigraphy and to discuss how subsoil heterogeneities control the 1D and 2D local seismic response in such a volcanic setting. We first introduce a new multidisciplinary dataset, including geological (fieldwork and log from a 45-m-thick continuous coring borehole), geophysical (electrical resistivity tomographies, single station noise measurements, and 2D passive seismic arrays), and geotechnical (simple shear tests performed on undisturbed samples) approaches. Then, we reconstruct the subsoil model for the Stracciacappa maar in terms of vertical setting and distribution of its mechanical lithotypes, which we investigate for 1D and 2D finite element site response analyses through the application of two different seismic scenarios: a volcanic event and a tectonic event. The numerical modelling documents a significant ground motion amplification (in the 1–1.5 Hz range) revealed for both seismic scenarios, with a maximum within the centre of the maar. The ground motion amplification is related to both 1D and 2D phenomena including lithological heterogeneity within the upper part of the maar section and interaction of direct S-waves with Rayleigh waves generated at edges of the most superficial lithotypes. Finally, we use these insights to associate the expected distribution of ground motion amplification with the physical stratigraphy of an explosive volcanic setting, with insights for seismic microzonation studies and local seismic response assessment in populated environments.

Download Full-text