The Effect of Site Condition on Ground Motion in Gansu Province during the Wenchun Ms8.0 Earthquake

2012 ◽  
Vol 594-597 ◽  
pp. 1658-1667
Author(s):  
Zhi Jian Wu ◽  
Lan Min Wang ◽  
Ping Wang ◽  
Hang Shi ◽  
Tuo Chen
Keyword(s):  
Seismic Response ◽  
Ground Motion ◽  
Seismic Design ◽  
Site Effects ◽  
Strong Motion ◽  
Gansu Province ◽  
Response Analysis ◽  
Site Condition ◽  
Seismic Response Analysis ◽  
Ground Acceleration

Based on mobile strong motion array observation, borehole exploration and site seismic response analysis, the site effects of mountainous topography in southeastern Gansu and the topography of loess tableland on ground motion were investigated in details. The analysis on acceleration records of aftershocks showed that the peak ground acceleration at top of the mountain is nearly 2 times of that at the foot of it. The seismic response analysis of sites shows that the loess tableland may amplify PGA by 1.44-2.0 times. Therefore, site effects of mountains and loess topography on ground motion should been taken account into seismic design.

Study on the Ground Response Analysis for Stiff Soil

2014 ◽  
Vol 915-916 ◽  
pp. 122-125
Author(s):  
Xiao Fei Li ◽  
Rui Sun ◽  
Xiao Bo Yu
Keyword(s):  
Seismic Response ◽  
Working Conditions ◽  
Strong Motion ◽  
Response Spectra ◽  
Response Analysis ◽  
Seismic Response Analysis ◽  
Ground Response Analysis ◽  
Ground Acceleration ◽  
Strong Motion Records ◽  
Stiff Soil

In order to test the applicable of the seismic response analysis procedures SHAKE2000 and LSSRLI-1 for class ІІ site, 17 stations and 35 underground strong motion records of KiK-net are selected from Class ІІ site. 210 working conditions are used to verify the applicability of the two soil seismic response analysis programs at Class ІІ site. These two programs are used to calculate the selected working conditions, giving the peak acceleration of the ground, the shear strain and the ground acceleration response spectra. By analyzing the results of the two programs and the measured results to assess the degree of difference between the two methods and which program is closer to the real situation. Studies have shown that in class ІІ site, in most cases, the results of SHAKE2000 and LSSRLI-1 differ little. While comparing with the actual records, SHAKE2000 is closer to the strong motion records.

scholarly journals Seismic response analysis for Romanian extra-carpathian sedimentary areas

2021 ◽  
pp. 83-92
Author(s):  
Gheorghe Marmureanu ◽  
Carmen Ortanza Cioflan ◽  
Bogdan Felix Apostol
Keyword(s):  
Seismic Response ◽  
Ground Motion ◽  
Site Effects ◽  
Spectral Characteristics ◽  
Response Analysis ◽  
Seismic Events ◽  
Seismic Response Analysis ◽  
Local Conditions ◽  
Sedimentary Deposits ◽  
New Perspective

The seismic response of the ground motion is analysed using processed recordings and related spectral characteristics. The analysis is carried out for few representative different sites, with different geological local conditions. Data used are recordings from the last strongest seismic events (1986, August 30, Mw = 7.1, 1990, May 30, Mw = 6.9 and 1990, May 31, Mw=6.4). The approach used herein to assess the particular features of the seismic effects could open a new perspective in microzoning and risk studies. In the context of Vrancea-intermediate depth seismicity, whose effects are encountered at long epicentral distances, the choice of these sites is fully justified. Therefore the paper intends to focus on the particularities in the site effects that occur due to the sedimentary deposits’ oscillation under strong seismic ground motion for different areas. The spectral amplification factors are introduced in order to have a quantitative representation with respect to the variability of site effects.

scholarly journals Seismic Hazard Assessment for the Tianshui Urban Area, Gansu Province, China

2012 ◽  
Vol 2012 ◽  
pp. 1-10 ◽  
Author(s):  
Zhenming Wang ◽  
David T. Butler ◽  
Edward W. Woolery ◽  
Lanmin Wang
Keyword(s):  
Seismic Hazard ◽  
Ground Motion ◽  
Seismic Design ◽  
Hazard Analysis ◽  
Seismic Hazard Assessment ◽  
Gansu Province ◽  
Mitigation Measures ◽  
Peak Ground Velocity ◽  
Ground Acceleration ◽  
Acceleration Time Histories

A scenario seismic hazard analysis was performed for the city of Tianshui. The scenario hazard analysis utilized the best available geologic and seismological information as well as composite source model (i.e., ground motion simulation) to derive ground motion hazards in terms of acceleration time histories, peak values (e.g., peak ground acceleration and peak ground velocity), and response spectra. This study confirms that Tianshui is facing significant seismic hazard, and certain mitigation measures, such as better seismic design for buildings and other structures, should be developed and implemented. This study shows that PGA of 0.3 g (equivalent to Chinese intensity VIII) should be considered for seismic design of general building and PGA of 0.4 g (equivalent to Chinese intensity IX) for seismic design of critical facility in Tianshui.

Nonstationary Probabilistic Seismic Response Analysis of Nonlinear Soil Profile under Bidirectional Dynamic Loading

2012 ◽  
Vol 193-194 ◽  
pp. 949-953
Author(s):  
Xiao Dong Pan ◽  
Jia En Zhong ◽  
Chao Chao He
Keyword(s):  
Spectral Density ◽  
Seismic Response ◽  
Ground Motion ◽  
Power Spectral Density ◽  
Soil Profile ◽  
Response Analysis ◽  
Time Varying ◽  
Seismic Response Analysis ◽  
Dynamic Reliability ◽  
Power Spectral

In this paper, according to the characteristics of near-fault earthquakes, combined with the strong ground motion attenuation law in China, the nonstationary power spectrum of bidirectional ground motion input is obtained through random vibration analysis. By introducing the pseudo excitation algorithm, the evolutionary power spectral density (PSD) of acceleration at the engineering bedrock is handled as the nonstationary pseudo input, and the Hardin-Drnevich hyperbolic model is utilized to take into account the nonlinearity of soil layer. On this basis, finite element method in the time domain and frequency domain are used for seismic response analysis of soil profile. Values including various time-varying power spectral density of the dynamic response, time varying RMS and time-dependent reliability at different threshold can be obtained by calculating, which provides a basis for the analysis of the foundation dynamic reliability assessment.

Seismic Response Analysis System by Means of Multibody Dynamics Approach: Modeling and Analysis of Geometric Time Varying Structure Systems

2005 ◽  
Author(s):  
Yoshitaka Takahashi ◽  
Nobuyuki Shimizu
Keyword(s):  
Seismic Response ◽  
Multibody Dynamics ◽  
Seismic Design ◽  
Building Construction ◽  
Response Analysis ◽  
Time Varying ◽  
Seismic Response Analysis ◽  
Modeling And Analysis ◽  
Beam Elements ◽  
Analysis System

In Japan, the seismic design methods for structures are developed in the civil and architectural fields. And these seismic design technologies have also been brought to mechanical structures such as piping facilities and boiler structures, etc.. But, for the geometric time varying structure of which geometric configuration is dependent on time such as cranes, the kinetic and the dynamic characteristics of such structures are not fully considered in the seismic response analyses. In this paper, we try the modeling of the geometric time varying structure systems by means of the method of multibody dynamics. And we examine the effect of the geometric time varying system on the seismic response. The beam elements formulated by the absolute nodal coordinate are used to model the structure that has large displacement motion of the base of the structure. The crane structure for the building construction is modeled in the numerical example. The seismic responses of the moving boom part of the crane model are simulated. New phenomenon has been explored.

Effect of Ground Motion Characteristics on Seismic Response of Large Span Bridge

2013 ◽  
Vol 275-277 ◽  
pp. 1407-1410
Author(s):  
Hai Ming Liu ◽  
Xia Xin Tao ◽  
Liang Wang ◽  
Shou Long Tian
Keyword(s):  
Seismic Response ◽  
Ground Motion ◽  
Earthquake Source ◽  
Maximum Response ◽  
Response Analysis ◽  
Seismic Response Analysis ◽  
Large Span ◽  
Internal Forces ◽  
Motion Characteristics ◽  
Main Girder

Result of seismic response analysis of a large span cable based bridge with inconsistent inputs is presented in a conjugated paper and is further deal with in this paper. The results from synthesized motions for the same earthquake source and same distance to the rupture show a large difference. They are compared with characteristics of the inputs in this paper. The effect of the motion amplitudes and the coherency between the input motions at the two ends of the main girder on the maximum response displacements and internal forces are pointed out.

scholarly journals Study on the influence of seafloor soft soil layer on seismic ground motion

2020 ◽  
Author(s):  
Jingyan Lan ◽  
Juan Liu ◽  
Xing Song
Keyword(s):  
Seismic Response ◽  
Ground Motion ◽  
Sea Water ◽  
Response Spectrum ◽  
Soft Soil ◽  
Free Field ◽  
Soil Layer ◽  
Response Analysis ◽  
Peak Acceleration ◽  
Seismic Response Analysis

Abstract. In the complex medium system of sea area, the overlying sea water and the surface soft soil have a significant impact on the seafloor ground motion, which brings great seismic risk to the safety of offshore engineering structures. In this paper, four sets of typical free field models are constructed and established, which are land model, land model with surface soft soil, sea model and sea model with surface soft soil. The dynamic finite difference method is used to carry out two-dimensional seismic response analysis of typical free field based on the input forms about P and SV wave. By comparing the seismic response analysis results of four groups of calculation models, the effects of overlying seawater and soft soil on peak acceleration and acceleration response spectrum are studied. The results show that when SV wave is input, the peak acceleration and response spectrum of the surface of soft soil on the surface and the seabed surface can be amplified, while the overlying sea water can significantly reduce the ground motion. When P wave is used, the effect of overlying seawater and soft soil on peak acceleration and response spectrum of surface and seabed can be ignored. The peak acceleration decreases first and then increases from the bottom to the surface, and the difference of peak acceleration calculated by four free field models is not obvious. The results show that the overlying sea water and the surface soft soil layer have little effect on the peak acceleration of ground motion below the surface.

Seismic Ground Response Analysis of Some Typical Sites of Guwahati City

2013 ◽  
Vol 4 (1) ◽  
pp. 83-101 ◽  
Author(s):  
Shiv Shankar Kumar ◽  
A. Murali Krishna
Keyword(s):  
Ground Motion ◽  
Amplitude Ratio ◽  
Response Spectrum ◽  
Strong Motion ◽  
Response Analysis ◽  
Ground Response ◽  
Ground Response Analysis ◽  
Ground Acceleration ◽  
Surface Level ◽  
Guwahati City

In this study, one dimensional equivalent–linear ground response analyses were performed for some typical sites in the Guwahati city, India. Six bore locations covering about 250 km2 area of the city were considered for the analyses. As the strong motion significantly influences the ground response, seven different recorded ground motions, varying in magnitude (6.1 to 8.1) and other ground motion parameters, were adopted. Seismic site analyses were carried out for all layers of borelogs using all the seven earthquakes. Results are presented in terms of surface acceleration histories, strain and shear stress ratio variation, response spectrum, Fourier amplitude ratio versus frequency. The results indicate that accelerations were amplified the most at the surface level. The range of peak ground acceleration (PGA) values obtained at the ground surface is about 0.2 g to 0.79 for a range of PGA considered at bedrock level (rigid half space at bottom of borelog) of 0.1 g to 0.34 g. The Fourier amplifications of ground motion at surface are in the range of 4.14 – 8.99 for a frequency band of 1.75 Hz to 3.13 Hz. The maximum spectral acceleration at six locations varies in the range of 1.0 g – 4.71 g for all the seven earthquakes. The study clearly demonstrated the role for site effect and the type of ground motion on the ground response. For a given earthquake motion, amplification factors at surface level change by almost about 20% to 70% depending on local site conditions.

Sign in / Sign up

Export Citation Format

Share Document