Comparison Of Typical Ground Motion Attenuation Relations Based On Strong Motion Records In Western China

It is well known that the attenuation relations have always been playing an important role in the field of the seismic safety evaluation,the seismic risk analysis,preparation of seismic zoning maps and the seismic design,etc.The theory of the seismic attenuation relationships have been improved over the past half century.Especially in recent years,the NGA(Next Generation of Attenuation Relationship)plan developed by the relevant departments of the United States represents the forefront of the research on the field of ground motion attenuation.Although the strong motion observation technology and the ground motion attenuation relationships research work of China started late,the ground motion attenuation relationships of China have made great progress through the continuous efforts the researchers and the continuous accumulation.At present,the main methods to establish the attenuation relationships are to use the observed strong motion records,or use intensity transformation method.Aiming at these two kinds of ground motion attenuation relationships,we use information-theory and residual analysis to compare five typical ground motion attenuation relationships of China,and finally determine the most suitable ground motion attenuation relationship of China.The main work and conclusions of this study are as follows:1.This paper introduces the current research situation of the ground motion attenuation relationships both at home and abroad,and the application of residual analysis and information theory.And the characteristics of the prediction results of the five models are compared preliminarily.The results show that the prediction results between Zhang Qi and Jiang Zhijun's models are close,and the prediction result of Huo Junrong's model attenuates faster than the results of other models.2.We collected and sorted out 57 earthquakes in China in recent ten years,and the earthquakes' magnitude is larger than 4.5,and the fault distance is less than 200 km.There are 636 strong motion records,and find the source information and part site information.For the unknown site information,the spectral ratio method is used to get the information.At the same time,we use the empirical formula to unify the magnitude and distance scale,and analysis the correlation between all the ground motion records and periods,and finally the data set is set up for this paper.3.Based on the data set and residual analysis and information-theory,the models and data set are divided into four groups according to the using conditions.The four groups of models are compared respectively.The results show that:(1)The strong motion attenuation relationships established by strong motion records(Yu Tian,Jiang Zhijun and Zhang Qi)are more suitable for the prediction of seismic response spectrum.(2)The magnitude parameters and site parameters are more suitable to predict the ground motion response spectrum of the earthquakes that have small and medium level magnitude and soil site;Zhang Qi's distance parameters are more suitable to predict the ground motion response spectrum of soil site;Jiang Zhijun's fault-type parameters are more suitable to predict the ground motion response spectrum.4.Four earthquakes with different magnitudes were selected in China,and research conclusions were applied to the four earthquakes,which further verified the reliability of the conclusions.