Seismic hazard assessment is an important stage in earthquake engineering.Since the ground motion prediction equation(GMPE)has a key role in seismic hazard assessment,it is necessary to determine this equation as well...Seismic hazard assessment is an important stage in earthquake engineering.Since the ground motion prediction equation(GMPE)has a key role in seismic hazard assessment,it is necessary to determine this equation as well as possible.Some mutual seismic parameters,such as earthquake magnitude,distance,fault type,and site effect,are applied in GMPEs.The ridge regression method is applied to find the relation between input seismic parameters and targets(PGA,PGV,PGD,SA(T=0.02 s),and SA(T=1 s)).Results of regression show that equations obtained in this study have a root mean square error(RMSE)of 90%.In the last part,GMPEs are inspected by sensitivity analysis through two methods:Sobol and Delta Moment-Independent Measure.The results from the two methods were very similar to each other for each equation.Furthermore,the analysis shows that the most effective parameters in determining GMPEs are moment magnitude and shear wave velocity.展开更多
The performance of a soil-pile system can be significantly influenced by ground motion parameters. However, few research efforts have been performed to provide a complete description of the influence of key ground mot...The performance of a soil-pile system can be significantly influenced by ground motion parameters. However, few research efforts have been performed to provide a complete description of the influence of key ground motion parameters on the pile’s behavior in liquefiable soil. In this study, a three-dimensional finite element（FE） model, incorporating a multisurface plasticity solid-fluid fully coupled formulation soil constitutive model, is developed and calibrated based on centrifuge test data. Seventy-two near-fault non-pulse-like（NF-NP） and seventy-two near-fault pulse-like（NF-P） ground motion records are studied with the calibrated FE model to distinguish the effects of several common ground motion parameters soon afterwards. Base on the parametric study results, a simple index, RPGV/PGA（i.e., the ratio of peak ground velocity（PGV） to peak ground acceleration（PGA））, shows its capability on characterizing the pile behavior under both NF-NP and NF-P ground motions. Furthermore, two equations are developed to characterize the relationships between the RPGV/PGA as well as the maximum pile’s moments and displacements. In general, this study can be helpful to gain new insights on the influence of typical index parameters for near-field ground motions on the response of the pile foundation in liquefiable soil.展开更多
Ground motion records are often used to develop ground motion prediction equations （GMPEs） for a randomly oriented horizontal component, and to assess the principal directions of ground motions based on the Arias in...Ground motion records are often used to develop ground motion prediction equations （GMPEs） for a randomly oriented horizontal component, and to assess the principal directions of ground motions based on the Arias intensity tensor or the orientation of the major response axis. The former is needed for seismic hazard assessment, whereas the latter can be important for assessing structural responses under multi-directional excitations. However, a comprehensive investigation of the pseudo-spectral acceleration （PSA） and of GMPEs conditioned on different axes is currently lacking. This study investigates the principal directions of strong ground motions and their relation to the orientation of the major response axis, statistics of the PSA along the principal directions on the horizontal plane, and correlation of the PSA along the principal directions on the horizontal plane. For these, three sets of strong ground motion records, including intraplate California earthquakes, inslab Mexican earthquakes, and interface Mexican earthquakes, are used. The results indicate that one of the principal directions could be considered as quasi-vertical. By focusing on seismic excitations on the horizontal plane, the statistics of the angles between the major response axis and the major principal axis are obtained; GMPEs along the principal axes are provided and compared with those obtained for a randomly oriented horizontal component; and statistical analysis of residuals associated with GMPEs along the principal directions is carried out.展开更多
As for many post-soviet countries, Kazakhstan’s building code for seismic design was based on a deterministic approach. Recently, Kazakhstan seismologists are engaged to adapt the PSHA(probabilistic hazard assessment...As for many post-soviet countries, Kazakhstan’s building code for seismic design was based on a deterministic approach. Recently, Kazakhstan seismologists are engaged to adapt the PSHA(probabilistic hazard assessment) procedure to the large amount of available geological, geophysical and tectonic Kazakh data and to meet standard requirements for the Eurocode 8. The new procedure has been used within National projects to develop the Probabilistic GSZ(General Seismic Zoning) maps of the Kazakhstan territory and the SMZ(Probabilistic Seismic Microzoning) maps of Almaty city. They agree with the seismic design principles of Eurocode 8 and are expressed in terms of not only seismic intensity,but also engineering parameters(peak ground acceleration PGA). The whole packet of maps has been developed by the Institute of Seismology, together with other Kazakhstan Institutions. Our group was responsible for making analysis in PGA. The GSZ maps and hazard assessment maps for SMZ in terms of PGA for return periods 475 and 2475 years are considered in the article.展开更多
Serial destructive earthquakes have caused heavy casualties and economic losses to the city in southwestern of China. The Ludian Ms 6.5 earthquake and the Jinggu Ms 6.6 earthquake occurred in Yunnan province in 2014. ...Serial destructive earthquakes have caused heavy casualties and economic losses to the city in southwestern of China. The Ludian Ms 6.5 earthquake and the Jinggu Ms 6.6 earthquake occurred in Yunnan province in 2014. There is a question of why the two events with almost the same level of magnitude caused differences in earthquake damage. To understand the uniqueness of the phenomenon, this paper focuses on the characteristics of the ground motions and post-earthquake field investigation for the two events. Firstly, we present an overview of the residuals between the Ludian earthquake and the Jinggu earthquake based on the YW06 Ground Motion Prediction Equation （GMPE）, and explain the unusual destructiveness of the strong ground motion. Then we analyze the ground motion recordings at selected typical station, based on the strong motion parameters： equivalent predominant frequency and Arias intensity. The result exhibits a good agreement with the Chinese seismic intensity scale. This study would be helpful to gain a better knowledge of the characteristics and variability of ground motions for Ms6 class earthquakes in China and to understand the implications to future earthquakes with similar focal mechanism and local condition.展开更多
Recent earthquakes in the Sichuan Province have contributed to significantly expand the existing ground-motion database for China with new,high-quality ground-motion records.This study investigated the compatibility o...Recent earthquakes in the Sichuan Province have contributed to significantly expand the existing ground-motion database for China with new,high-quality ground-motion records.This study investigated the compatibility of ground-motion prediction equations(GMPEs)established by the NGA-West2 project in the US and local GMPEs for China,with respect to magnitude scaling,distance scaling,and site scaling implied by recent Chinese strong-motion data.The NGA-West2 GMPEs for shallow crustal earthquakes in tectonically active regions are considerably more sophisticated than widely used previous models,particularly in China.Using a mixed-effects procedure,the study evaluated event terms(inter-event residuals)and intra-event residuals of Chinese data relative to the NGA-West2 GMPEs.Distance scaling was investigated by examining trends of intra-event residuals with source-to-site distance.Scaling with respect to site conditions was investigated by examining trends of intra-event residuals with soil type.The study also investigated other engineering characteristics of Chinese strong ground motions.In particular,the records were analyzed for evidence of pulse-like forward-directivity effects.The elastic median response spectra of the selected stations were compared to code-mandated design spectra for various mean return periods.Results showed that international and local GMPEs can be applied for seismic hazard analysis in Sichuan with minor modification of the regression coefficients related to the source-to-site distance and soil scaling.Specifically,the Chinese data attenuated faster than implied by the considered GMPEs and the differences were statistically significant in some cases.Near-source,pulse-like ground motions were identified at two recording stations for the 2008 Wenchuan earthquake,possibly implying rupture directivity.The median recorded spectra were consistent with the code-based spectra in terms of amplitude and shape.The new ground-motion data can be used to develop advanced ground-motion models for China and worldwide and,ultimately,for advancing probabilistic seismic hazard assessment(PSHA).展开更多
文摘Seismic hazard assessment is an important stage in earthquake engineering.Since the ground motion prediction equation(GMPE)has a key role in seismic hazard assessment,it is necessary to determine this equation as well as possible.Some mutual seismic parameters,such as earthquake magnitude,distance,fault type,and site effect,are applied in GMPEs.The ridge regression method is applied to find the relation between input seismic parameters and targets(PGA,PGV,PGD,SA(T=0.02 s),and SA(T=1 s)).Results of regression show that equations obtained in this study have a root mean square error(RMSE)of 90%.In the last part,GMPEs are inspected by sensitivity analysis through two methods:Sobol and Delta Moment-Independent Measure.The results from the two methods were very similar to each other for each equation.Furthermore,the analysis shows that the most effective parameters in determining GMPEs are moment magnitude and shear wave velocity.
基金National Key R&D Program of China under Grant No.2016YFE0205100the National Natural Science Foundation of China under Grant No.51578195+1 种基金the Technology Research and Development Plan Program of China Railway Corporation under Grant No.J2016Z025the Open Research Fund of State Key Laboratory of Geomechanics and Geotechnical Engineering,Institute of Rock and Soil Mechanics,Chinese Academy of Sciences under Grant No.Z016007
文摘The performance of a soil-pile system can be significantly influenced by ground motion parameters. However, few research efforts have been performed to provide a complete description of the influence of key ground motion parameters on the pile’s behavior in liquefiable soil. In this study, a three-dimensional finite element（FE） model, incorporating a multisurface plasticity solid-fluid fully coupled formulation soil constitutive model, is developed and calibrated based on centrifuge test data. Seventy-two near-fault non-pulse-like（NF-NP） and seventy-two near-fault pulse-like（NF-P） ground motion records are studied with the calibrated FE model to distinguish the effects of several common ground motion parameters soon afterwards. Base on the parametric study results, a simple index, RPGV/PGA（i.e., the ratio of peak ground velocity（PGV） to peak ground acceleration（PGA））, shows its capability on characterizing the pile behavior under both NF-NP and NF-P ground motions. Furthermore, two equations are developed to characterize the relationships between the RPGV/PGA as well as the maximum pile’s moments and displacements. In general, this study can be helpful to gain new insights on the influence of typical index parameters for near-field ground motions on the response of the pile foundation in liquefiable soil.
基金Natural Science and Engineering Research Council of Canada(NSERC)
文摘Ground motion records are often used to develop ground motion prediction equations （GMPEs） for a randomly oriented horizontal component, and to assess the principal directions of ground motions based on the Arias intensity tensor or the orientation of the major response axis. The former is needed for seismic hazard assessment, whereas the latter can be important for assessing structural responses under multi-directional excitations. However, a comprehensive investigation of the pseudo-spectral acceleration （PSA） and of GMPEs conditioned on different axes is currently lacking. This study investigates the principal directions of strong ground motions and their relation to the orientation of the major response axis, statistics of the PSA along the principal directions on the horizontal plane, and correlation of the PSA along the principal directions on the horizontal plane. For these, three sets of strong ground motion records, including intraplate California earthquakes, inslab Mexican earthquakes, and interface Mexican earthquakes, are used. The results indicate that one of the principal directions could be considered as quasi-vertical. By focusing on seismic excitations on the horizontal plane, the statistics of the angles between the major response axis and the major principal axis are obtained; GMPEs along the principal axes are provided and compared with those obtained for a randomly oriented horizontal component; and statistical analysis of residuals associated with GMPEs along the principal directions is carried out.
基金"Development of the Map of General Seismic Zoning in the Territory of the Republic of Kazakhstan" (state registration 0113RK01142)"Development of the map of Seismic Microzoning of the Territory of Almaty City"(state registration 0115RK02701)funded within the state funding
文摘As for many post-soviet countries, Kazakhstan’s building code for seismic design was based on a deterministic approach. Recently, Kazakhstan seismologists are engaged to adapt the PSHA(probabilistic hazard assessment) procedure to the large amount of available geological, geophysical and tectonic Kazakh data and to meet standard requirements for the Eurocode 8. The new procedure has been used within National projects to develop the Probabilistic GSZ(General Seismic Zoning) maps of the Kazakhstan territory and the SMZ(Probabilistic Seismic Microzoning) maps of Almaty city. They agree with the seismic design principles of Eurocode 8 and are expressed in terms of not only seismic intensity,but also engineering parameters(peak ground acceleration PGA). The whole packet of maps has been developed by the Institute of Seismology, together with other Kazakhstan Institutions. Our group was responsible for making analysis in PGA. The GSZ maps and hazard assessment maps for SMZ in terms of PGA for return periods 475 and 2475 years are considered in the article.
基金supported by the National Key R&D Program of China No. 2017YFC1500801the National Natural Science Fundation of China granted Nos. 51778589 and 51308515+1 种基金Heilongjiang Province Natural Science Fund granted No. E2017065the National Key Research and Development Program granted No. 2017YFC150165
文摘Serial destructive earthquakes have caused heavy casualties and economic losses to the city in southwestern of China. The Ludian Ms 6.5 earthquake and the Jinggu Ms 6.6 earthquake occurred in Yunnan province in 2014. There is a question of why the two events with almost the same level of magnitude caused differences in earthquake damage. To understand the uniqueness of the phenomenon, this paper focuses on the characteristics of the ground motions and post-earthquake field investigation for the two events. Firstly, we present an overview of the residuals between the Ludian earthquake and the Jinggu earthquake based on the YW06 Ground Motion Prediction Equation （GMPE）, and explain the unusual destructiveness of the strong ground motion. Then we analyze the ground motion recordings at selected typical station, based on the strong motion parameters： equivalent predominant frequency and Arias intensity. The result exhibits a good agreement with the Chinese seismic intensity scale. This study would be helpful to gain a better knowledge of the characteristics and variability of ground motions for Ms6 class earthquakes in China and to understand the implications to future earthquakes with similar focal mechanism and local condition.
基金Community Based Disaster Management in Asia Programme Phase Ⅱ (CBDM Asia Phase Ⅱ) (00084327)
文摘Recent earthquakes in the Sichuan Province have contributed to significantly expand the existing ground-motion database for China with new,high-quality ground-motion records.This study investigated the compatibility of ground-motion prediction equations(GMPEs)established by the NGA-West2 project in the US and local GMPEs for China,with respect to magnitude scaling,distance scaling,and site scaling implied by recent Chinese strong-motion data.The NGA-West2 GMPEs for shallow crustal earthquakes in tectonically active regions are considerably more sophisticated than widely used previous models,particularly in China.Using a mixed-effects procedure,the study evaluated event terms(inter-event residuals)and intra-event residuals of Chinese data relative to the NGA-West2 GMPEs.Distance scaling was investigated by examining trends of intra-event residuals with source-to-site distance.Scaling with respect to site conditions was investigated by examining trends of intra-event residuals with soil type.The study also investigated other engineering characteristics of Chinese strong ground motions.In particular,the records were analyzed for evidence of pulse-like forward-directivity effects.The elastic median response spectra of the selected stations were compared to code-mandated design spectra for various mean return periods.Results showed that international and local GMPEs can be applied for seismic hazard analysis in Sichuan with minor modification of the regression coefficients related to the source-to-site distance and soil scaling.Specifically,the Chinese data attenuated faster than implied by the considered GMPEs and the differences were statistically significant in some cases.Near-source,pulse-like ground motions were identified at two recording stations for the 2008 Wenchuan earthquake,possibly implying rupture directivity.The median recorded spectra were consistent with the code-based spectra in terms of amplitude and shape.The new ground-motion data can be used to develop advanced ground-motion models for China and worldwide and,ultimately,for advancing probabilistic seismic hazard assessment(PSHA).
