掲載雑誌（和）： 日本地震工学シンポジウム講演集 Vol： 5巻 年： 1978年 頁： 97-104頁 著者（和）： - タイトル（和）： - 抄録（和）：
- キーワード（和）： - 掲載雑誌（英）： PROCEEDINGS OF JAPAN EARTHQUAKE ENGINEERING SYMPOSIUM 著者（英）： Tetsuo KUBO, Joseph PENZIEN タイトル（英）： ANALYSIS OF THREE-DIMENSIONAL EARTHQUAKE GROUND MOTION ALONG AN ORTHOGONAL SET OF PRINCIPAL AXES 抄録（英）：
An orthogonal set of principal axes is defined for a three-dimensional earthquake ground motion. These principal axes are obtained along which the corresponding components of motion have maximum, minimum and intermediate values of variances and have zero values of covariances. This property indicates that the components of motion along principal axes are fully uncorrelated with one another. Analysis of real earthquake motions suggests that earthquake accelerograms are well represented by Gaussian random processes. In a statistical sense, the corresponding three components of motion along a set of principal axes are independent of one another. Using the concept of an orthogonal set of principal axes and applying the moving-window technique in time domain to the accelerograms recorded during the San Fernando earthquake of 1971, analyses of three-dimensional earthquake ground motions are carried out along their principal axes. In these analyses, time-dependent characteristics of principal variances and directions of principal axes of motion are determined. Results of the analyses reveal a tendency of directions of the major principal axis of motion, or in some cases the intermediate principal axis, to point towards the fault slip zone. It is concluded that three-dimensional earthquake ground motions can be generated stochastically by use of mutually independent random processes, provided the components of motion are directed along their corresponding principal axes. キーワード（英）： - 記事区分： - 区分 　　　委員会論文集