�@ Œf�ÚŽGŽ��i˜a�j�F “ú–{’n�k�HŠwƒVƒ“ƒ|ƒWƒEƒ€˜_•¶�W Vol�F 9-1Šª ”N�F 1994”N •Å�F 637-642•Å ’˜ŽÒ�i˜a�j�F ‘å’Ë�@‹v“N�C�@Šâ�è�@�G–¾�C�@ˆéŽR�@—´“ñ�C�@•Ÿ“c�@�_�º ƒ^ƒCƒgƒ‹�i˜a�j�F ‹­�k‹L˜^‚ÉŠî‚­�kŒ¹‹ß–T‚Ì�Å‘å‰Á‘¬“x‚̑傫‚³ �´˜^�i˜a�j�F
- ƒL�[ƒ��[ƒh�i˜a�j�F - Œf�ÚŽGŽ��i‰p�j�F PROCEEDINGS OF THE JAPAN EARTHQUAKE ENGINEERING SYMPOSIUM ’˜ŽÒ�i‰p�j�F Hisanori OTSUKA, Hideaki IWASAKI, Ryoji ISOYAMA, Hiroaki FUKUDA ƒ^ƒCƒgƒ‹�i‰p�j�F NEAR SOURCE PEAK ACCELERATIONS BASED ON THE OBSERVED RECORDS �´˜^�i‰p�j�F
Attenuation characteristics of peak horizontal acceleration in the near-source region were studied for 103 earthquakes observed in and outside of Japan. Attempts were made to derive attenuation relations not based on the functional forms of existing attenuation equations. Results are summarized as follows: (1) there is a certain distance range for an earthquake for which peak acceleration can be considered constant, and this distance range is in proportion to magnitude; (2) the constant value for peak acceleration in this distance range is dependent upon magnitude; (3) this magnitude dependence has been expressed in a functional form of log Acc=aM + b, where Acc is peak horizontal acceleration and M is magnitude. ƒL�[ƒ��[ƒh�i‰p�j�F - ‹LŽ–‹æ•ª�F - ‹æ•ª �@�@�@ˆÏˆõ‰ï˜_•¶�W