In this paper, the amplification factor （ks ） of peek ground motion with different exceedance probability in class Ⅱ and Ⅲ sites over Shandong Province was estimated by analyzing the seismic response data of soil ...In this paper, the amplification factor （ks ） of peek ground motion with different exceedance probability in class Ⅱ and Ⅲ sites over Shandong Province was estimated by analyzing the seismic response data of soil layers collected from 358 boreholes of class Ⅱ sites and 140 boreholes of class Ⅲ site. From the results, one can conclude that： （1） The scatter plot of ks generally obeys a normal distribution ; （2） ks decreases with the increase of the strength of input ground motion, which is more apparent in Class Ⅲ site than in class lI site; （3） for class Ⅱ site, with the increase of depth of the bedrock interface where ground motion inputs, ks increases gradually until to a stable value when the depth reaches up to approximately 20 meters or larger. Yet, for class Ⅲ site, ks is insensitive to the depth; （4） the average of ks for class Ⅱ site is 1.47, slightly larger than that used in the Seismic Ground Motion Parameters Zonation Map of China （ GB 18306-2001 ）. Also, ks in class Ⅱ and Ⅲ sites at different levels of peak ground acceleration over Shandong Province is preliminarily discussed in the paper.展开更多
On the basis of the interpretation of the highresolution satellite remote sensing images, in combination with the data of engineering geological exploration and shear-wave velocity testing, the site category-zoning ma...On the basis of the interpretation of the highresolution satellite remote sensing images, in combination with the data of engineering geological exploration and shear-wave velocity testing, the site category-zoning map of FJ area with the scale of 1：200,000 is generated according to the site classification standard of ＂Code for Seismic design of Buildings＂ of China （GB50011 2010）. By the method of Probabilistic Seismic Hazard Analysis, we obtain bedrock seismic ground motion parameters of five recurrent periods （50, 200, 500, 1000, and 2500 a） of FJ area. By using the 617 typical soil layer structures of the site classifications in FJ area, we build seismic response models of soil layers and make seismic response analysis, then obtain the statistic sample space of site amplification factors, which possess reasonable distribution and sufficient data. Considering the distribution characteristics of The Quaternary Strata in FJ area, according to the statistic zoning （mountains and coastal areas respectively） and site classifications as well as the level of bedrock importing ground motion, the site magnification-factors of ground motion in FJ area are obtained by classification statistics.展开更多
The strength reduction factors are not only the key factors in determining seismic action for force-based seismic design, but also the key parameters to derive the inelastic response spectra for performance-based seis...The strength reduction factors are not only the key factors in determining seismic action for force-based seismic design, but also the key parameters to derive the inelastic response spectra for performance-based seismic design. In this paper, with a high quality ground motion database that includes a reasonable-sized set of records from China, a statistical study on the strength reduction factors is conducted and a new expression of strength reduction factors involving classification of design earthquake, which is an important concept to determine design spectra in Chinese seismic design code, is proposed. The expression of strength reduction factors can reflect the ground motion characteristics of China to a certain extent and is particularly suitable for Chinese seismic design. Then, the influence effects of site condition, classification of design earthquake, period of vibration, ductility level, earthquake magnitude and distance to fault on strength reduction factors are investigated. It is concluded that the effect of site condition on the strength reduction factors cannot be neglected, especially for the short-period structures of higher ductility. The classification of design earthquake also has an important effect on strength reduction factors and it may be unsuitable to use the existing expressions of strength reduction factors to the design spectra of current Chinese seismic code. The earthquake magnitude has no practical effect on strength reduction factors and if the near-fault records with forward directivity effect are not taken into consideration, the effect of distance to fault on strength reduction factors can also be neglected.展开更多
基金supported by Shandong Institute of Earthquake Engineering(Natural Science Foundation of Shandong Province(Y2002E01)Shandong Science and Technology Development Project(2010GSF10806),China
文摘In this paper, the amplification factor （ks ） of peek ground motion with different exceedance probability in class Ⅱ and Ⅲ sites over Shandong Province was estimated by analyzing the seismic response data of soil layers collected from 358 boreholes of class Ⅱ sites and 140 boreholes of class Ⅲ site. From the results, one can conclude that： （1） The scatter plot of ks generally obeys a normal distribution ; （2） ks decreases with the increase of the strength of input ground motion, which is more apparent in Class Ⅲ site than in class lI site; （3） for class Ⅱ site, with the increase of depth of the bedrock interface where ground motion inputs, ks increases gradually until to a stable value when the depth reaches up to approximately 20 meters or larger. Yet, for class Ⅲ site, ks is insensitive to the depth; （4） the average of ks for class Ⅱ site is 1.47, slightly larger than that used in the Seismic Ground Motion Parameters Zonation Map of China （ GB 18306-2001 ）. Also, ks in class Ⅱ and Ⅲ sites at different levels of peak ground acceleration over Shandong Province is preliminarily discussed in the paper.
文摘On the basis of the interpretation of the highresolution satellite remote sensing images, in combination with the data of engineering geological exploration and shear-wave velocity testing, the site category-zoning map of FJ area with the scale of 1：200,000 is generated according to the site classification standard of ＂Code for Seismic design of Buildings＂ of China （GB50011 2010）. By the method of Probabilistic Seismic Hazard Analysis, we obtain bedrock seismic ground motion parameters of five recurrent periods （50, 200, 500, 1000, and 2500 a） of FJ area. By using the 617 typical soil layer structures of the site classifications in FJ area, we build seismic response models of soil layers and make seismic response analysis, then obtain the statistic sample space of site amplification factors, which possess reasonable distribution and sufficient data. Considering the distribution characteristics of The Quaternary Strata in FJ area, according to the statistic zoning （mountains and coastal areas respectively） and site classifications as well as the level of bedrock importing ground motion, the site magnification-factors of ground motion in FJ area are obtained by classification statistics.
基金National Natural Science Foundation of China (50538050), Science Foundation of Heilongjiang Province (ZJG03-03)
文摘The strength reduction factors are not only the key factors in determining seismic action for force-based seismic design, but also the key parameters to derive the inelastic response spectra for performance-based seismic design. In this paper, with a high quality ground motion database that includes a reasonable-sized set of records from China, a statistical study on the strength reduction factors is conducted and a new expression of strength reduction factors involving classification of design earthquake, which is an important concept to determine design spectra in Chinese seismic design code, is proposed. The expression of strength reduction factors can reflect the ground motion characteristics of China to a certain extent and is particularly suitable for Chinese seismic design. Then, the influence effects of site condition, classification of design earthquake, period of vibration, ductility level, earthquake magnitude and distance to fault on strength reduction factors are investigated. It is concluded that the effect of site condition on the strength reduction factors cannot be neglected, especially for the short-period structures of higher ductility. The classification of design earthquake also has an important effect on strength reduction factors and it may be unsuitable to use the existing expressions of strength reduction factors to the design spectra of current Chinese seismic code. The earthquake magnitude has no practical effect on strength reduction factors and if the near-fault records with forward directivity effect are not taken into consideration, the effect of distance to fault on strength reduction factors can also be neglected.
