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： 449-456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）： F.P. MULLER, K. RONNBERG タイトル（英）： STIFF STRUCTURES ON A LAYERED MEDIUM UNDER EARTHQUAKE EXCITATION 抄録（英）：
A study of the earthquake excited vibrations of stiff structures on a layered medium is presented. Special emphasis is placed on the influence of dynamic building-foundation interaction. The impedance functions for a layered elastic medium show a much stronger frequency dependence than the impedance functions for the elastic halfspace. The impedance functions for a layered elastic medium are extended to the case of a layered viscoelastic medium making use of the correspondence principle in the frequency range of interest. A linear-hysteretic model is assumed for the internal damping in the soil. The equations of motion are first solved for harmonic excitation. It is shown that for a layered, viscoelastic medium constant, I.e. frequency independent impedance functions can be used as an approximation. For earthquake excited vibrations the calculations are performed in the time domain using the method of Foss. Constant impedance functions are determined in an iterative process. An approximated solution is found by the modal analysis method. An equivalent viscous damping ratio is assigned to each mode of vibration. It is determined as a weighted average of the elastic energies stored in the springs of the system. It is found that the modal analysis method gives a good approximation of the exact response for a lightly damped system. For a system with strong damping, however, the use of reduction factors in determining the modal dampings is suggested. キーワード（英）： - 記事区分： - 区分 　　　委員会論文集