• Title/Summary/Keyword: Ground Response Analysis

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Analysis of Response Spectrum of Ground Motions from Mine Blasting (발파에 의한 지반진동의 응답스펙트럼 분석)

  • Kim, Jun-Kyoung
    • Tunnel and Underground Space
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    • v.15 no.5 s.58
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    • pp.338-343
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    • 2005
  • This study analysed response spectrum using the observed ground motion from the mine blasting and, then compared the results to the seismic design response spectra applied domestic nuclear power plants. The results showed that the resultant response spectra above 20 Hz revealed higher values than the design response spectra and those below 20 Hz revealed much lower values. These facts suggest that the analysis of response spectrum should be applied to the analysis of impacts to frequency dependent structures in addition to the analysis of peak values of ground motions.

Response Analysis of Ground Vibration for Cutting and Embankment Transition Zone Structure (절성토 접속구조별 지반진동 응답특성)

  • Lee, Il-Wha;Yun, Won-Min;Choi, Won-Il;Hwang, In-Hwan;Hwang, Sung-Wook
    • Proceedings of the KSR Conference
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    • 2011.10a
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    • pp.3195-3200
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    • 2011
  • The vibration resulting from railway operation is transmitted through the track and line structure, ground movements to adjacent buildings. As these vibration is growing, there is occurred exaggerated forces and displacements of the track and line structure and it is causing the differential settlement. It is difficult to clarify the dynamic response characteristics of trackbed because of various environmental conditions. However, track irregularity be affected by ununiformed bearing capacity and its dynamic response, study for dynamic response characteristics is required to investigate the cause of track irregularity and countermeasure. This study was intended to evaluate the numerical analysis which exam the response analysis characteristic of ground vibration by shape of cutting and embankment transition zone. The original method of analysis were have to examine variables such as directions, angles, drain conditions, linear conditions. However, In the analysis there were to consider the effect of moving loads according to directions of cutting and embankment transition zone.

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1D Probabilistic Ground Response Analysis (지반 구조의 불확실성이 고려된 1차원 확률론적 지반응답해석)

  • Hwang, Hea Jin;Park, Hyung Choon
    • Journal of the Earthquake Engineering Society of Korea
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    • v.18 no.2
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    • pp.73-78
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    • 2014
  • In this paper, the stochastic 1D site response analysis method using Monte Carlo simulation and considering thespatial variation of shear wave velocity profile isproposed. To consider thespatial variation of shear wave velocity profile for 1D site response analysis, the proposed method generates random shear wave velocity profiles representing the target site, and Monte Carlo simulation is used to calculate theprobability distribution of the site response analysis results such as thepeak ground acceleration. Through the field application, The applicability of the proposed method is verified through field application.

Conversion of Recorded Ground Motion to Virtual Ground Motion Compatible to Design Response Spectra (계측 기록의 설계스펙트럼 부합 가상 지진 변환 방법)

  • Ji, Hae Yeon;Choi, Da Seul;Kim, Jung Han
    • Journal of the Earthquake Engineering Society of Korea
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    • v.25 no.1
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    • pp.33-42
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    • 2021
  • The design response spectrum presented in the seismic design standard reflects the characteristics of the tectonic environment at a site. However, since the design response spectrum does not represent the ground motion with a specific earthquake magnitude or distance, input ground motions for response history analysis need to be selected reasonably. It is appropriate to use observed ground motions recorded in Korea for the seismic design. However, recently recorded ground motions in the Gyeongju (2016) or Pohang (2017) earthquakes are not compatible with the design response spectrum. Therefore, it is necessary to convert the recorded ground motion in Korea to a model similar to the design response spectrum. In this study, several approaches to adjust the spectral acceleration level at each period range were tested. These are the intrinsic and scattering attenuation considering the earthquake environment, magnitude, distance change by the green function method, and a rupture propagation direction's directivity effect. Using these variables, the amplification ratio for the representative natural period was regressed. Finally, the optimum condition compatible with the design response spectrum was suggested, and the validation was performed by converting the recorded ground motion.

Comprehensive Evaluation of Results of Ground Response analysis Round Robin Test (지반응답해석 Round Robin Test 결과 종합적 분석 연구)

  • Park, Du-Hee;Yoon, Jong-Ku;Park, Young-Ho;Ahn, Chang-Yoon;Kim, Jae-Yeon
    • Proceedings of the Korean Geotechical Society Conference
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    • 2007.09a
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    • pp.334-344
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    • 2007
  • This paper performed a comprehensive evaluation of the results of the 2007 Ground Response Analysis Round Robin Test, at which 14 institutions and individuals participated. The submitted results showed significant discrepancies. The main reason for this difference has been attributed to the dispersion in the estimated shear wave velocity profiles and dynamic soil curves. It is therefore concluded that accurate evaluation of the material properties is of primary importance for reliable estimation of the ground vibration. Evaluation of the effect of the analysis method showed that the equivalent linear analysis overestimates the peak ground acceleration, but overall the results are similar to a total stress nonlinear analysis. However, the total and effective stress nonlinear analyses show distinct discrepancies, the effective stress analyses consistently resulting in a lower response due to the development of the excess pore water pressure and thus softer response.

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A Method for Selecting Ground Motions Considering Target Response Spectrum Mean, Variance and Correlation - II Seismic Response (응답 스펙트럼의 평균과 분산, 상관관계를 모두 고려한 지반운동 선정 방법 - II 지진 응답)

  • Ha, Seong Jin;Han, Sang Whan
    • Journal of the Earthquake Engineering Society of Korea
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    • v.20 no.1
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    • pp.63-70
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    • 2016
  • This study is the sequel of a companion paper (I. Algorithm) for assessment of the seismic performance evaluation of structure using ground motions selected by the proposed algorithm. To evaluate the effect of the correlation structures of selected ground motions on the seismic responses of a structure, three sets of ground motions are selected with and without consideration of the correlation structure. Nonlinear response history analyses of a 20-story reinforced concrete frame are conducted using the three sets of ground motions. This study shows that the seismic responses of the frames vary according to ground motion selection and correlation structures.

Assessment of Code-specified Ground Motion Selection Criteria with Accurate Selection and Scaling Methods - I Ground Motion Selection (구조물 동적해석을 위한 현행 내진설계기준의 입력 지반 운동 선정 조건 타당성 평가 - I 선정방법)

  • Ha, Seong Jin;Han, Sang Whan;Ji, Hyun Woo
    • Journal of the Earthquake Engineering Society of Korea
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    • v.21 no.4
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    • pp.171-179
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    • 2017
  • For estimating the seismic demand of buildings, most seismic design provisions permit conducting linear and nonlinear response history analysis. In order to obtain reliable results from response history analyses, a proper selection of input ground motions is required. In this study, an accurate algorithm for selecting and scaling ground motions is proposed, which satisfies the ASCE 7-10 criteria. In the proposed algorithm, a desired number of ground motions are sequentially scaled and selected from a ground motion library without iterations.

Seismic response analysis of layered soils considering effect of surcharge mass using HFTD approach. Part Ι: basic formulation and linear HFTD

  • Saffarian, Mohammad A.;Bagheripour, Mohammad H.
    • Geomechanics and Engineering
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    • v.6 no.6
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    • pp.517-530
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    • 2014
  • Seismic ground response analysis is one of the most important issues in geotechnical earthquake engineering. Conventional seismic site response and free field analysis of layered soils does not consider the effect of surcharge mass which may be present on the top layer. Surcharge mass may develop extra inertial force to the soil and, hence, significantly affect on the results of seismic ground response analysis. Methods of analysis of ground response may also be categorized into time domain and frequency domain concepts. Simplicity in developing analytical relations and accuracy in considering soil dynamic properties dependency to loading frequency are benefits of frequency domain analysis. In this part of the paper, seismic ground response is analyzed using transfer function method for soil layers considering surcharge mass on the top layer. Equation of motion, wave equation, is solved using amended boundary conditions which effectively take the impact of surcharge mass into account. A computer program is developed by MATLAB software based on the solution method developed for wave equation. Layered soils subjected to earthquake loading were numerically studied and solved especially by the computer program developed in this research. Results obtained were compared with those given by DEEP SOIL computer program. Such comparison showed the accuracy of the program developed in this study. Also in this part, the effects of geometrical and mechanical properties of soil layers and especially the impact of surcharge mass on transfer function are investigated using the current approach and the program developed. The efficiency and accuracy of the method developed here is shown through some worked examples and through comparison of the results obtained here with those given by other approaches. Discussions on the results obtained are presented throughout in this part.

Characteristics of Response Spectrum using Observed Ground Motion from the Recent Earthquakes (내진설계를 위한 응답스펙트럼 연구)

  • Kim, Jun-Kyoung
    • Proceedings of the KSEEG Conference
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    • 1999.04a
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    • pp.116-119
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    • 1999
  • Amplification factor spectrum, using the observed strong ground motions database in the Korean Peninsula, has been obtained and compared with Standard Response Spectrum, which was suggested by United States Nuclear Regulatory Committee. The observed und motions from the Yongwol and the Kyoungju, and the other recent Earthquakes, respectively, which ate supposed to represent domestic seismotectonic characteristics such as seismic source, attenuation of the propagation medium, and site specific effect, are used for the analysis of amplification factor spectrum. The database are slightly different from the those of the second study. Amplification factors hue been calculated by comparing the observed peak ground motions with results from responses to the observed horizontal na vertical ground motions. The comparison have shown that the amplification factors resultant from this study exceeds these of Standard Response Spectrum, The results suggest that the characteristics of seismic strong ground motion, which are supposed to represent the domestic seismotectonic characteristics, differs from those of Standard Response Spectrum, especially at higher frequencies. The results from the 2nd study are similar to those of 1st analysis.

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Nonlinear Seismic Estimates of Recorded and Simulated Ground Motions Normalized by the Seismic Design Spectrum (설계용 탄성응답스펙트럼으로 규준화된 인공지진동과 기록지진동의 비선형 지진응답)

  • Jun, Dae-Han;Kang, Pyeong-Doo;Kim, Jae-Ung
    • Journal of the Earthquake Engineering Society of Korea
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    • v.15 no.5
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    • pp.25-33
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    • 2011
  • In the nonlinear response history analysis of building structures, the input ground accelerations have considerable effect on the nonlinear response characteristics of structural systems. As the properties of the ground motion, using time history analysis, are interrelated with many factors such as the fault mechanism, the seismic wave propagation from source to site, and the amplification characteristics of the soil, it is difficult to properly select the input ground motions for seismic response analysis. In this paper, the most unfavourable real seismic design ground motions were selected as input motions. The artificial earthquake waves were generated according to these earthquake events. The artificial waves have identical phase angles to the recorded earthquake waves, and their overall response spectra are compatible with the seismic design spectrum with 5% of critical viscous damping. It is concluded that the artificial earthquake waves simulated in this paper are applicable as input ground motions for a seismic response analysis of building structures.