摘要
強地動衰減式(ground-motion attenuation)乃是推求地震動大小與震源、距離及場址間的經驗關係式，過去台灣地區的衰減式多僅考慮PGA，且所考慮的震源、路徑及場址參數也不夠詳盡。近年來，位於加州柏克萊大學(UC Berkeley)的太平洋地震科學研究中心(Pacific Earthquake Engineering Research Center, PEER)建立了一個包含全世界地殼地震的強震資料庫系統，並且利用此資料庫於今年度完成了新一代的強地動衰減式Next Generation Attenuation of Ground Motions Project (NGA)，目前一共有五組研究團隊分別完成五組不同的衰減式 (Boore and Atkison, 2007; Campbell and Bozorgnia, 2007; Chiou and Youngs, 2006; Idriss, 2007; Abrahamson and Silva, 2007)。
鑑於國內地震評估所採用之強地動衰減式已不敷使用，無法實際反應斷層破裂引發地震之強地動特性，故擬提出本計畫兩年執行完成與NGA相同水準且本土化之強地動衰減式，首先第一年擬採用強震資料庫中的地殼震源強震資料(本社目前已委託中央大學應用地質研究陸續建置中)，根據NGA計畫的研究成果，本計畫將建立符合台灣地區工程界地震評估需求之PGA與各週期反應譜加速度值之地動衰減式。此外，為了增加地震工程上的實用性，本研究也將建立PGV、PGD及Ia (愛氏震度，Arias Intensity)的衰減式。第二年本社將與美國加州運輸部的丘士正博士共組一個團隊與PEER合作，則針對隱沒帶震源，參與NGA計畫下一階段隱沒帶震源衰減式的研究。研究期間將會與PEER其他的NGA研究團隊進行討論，促進本社參與國際工程技術研討之合作機會。該研究成果將有助於本社持續改進地震危害度分析技術，並維持國內地震危害度分析評估技術領先之地位。

Abstract
Ground-motion attenuation relationship is an empirical relation for the estimation of ground shaking with earthquake magnitude, distance and site characteristic. Most of previous attenuation relationships in Taiwan only consider PGA and no detail information about earthquake source, path and site condition. In recent years, the Pacific Earthquake Engineering Research Center (PEER) in UC Berkeley has established world wide strong motion database (NGA database), and use this database in the Next Generation Attenuation of Ground Motions Project (NGA) to build up new attenuation relationship. There are total of five different attenuation relationships been made. (Boore and Atkison, 2007; Campbell and Bozorgnia, 2007; Chiou and Youngs, 2006; Idriss, 2007; Abrahamson and Silva, 2007)
 In views of the attenuation relationships in Taiwan can’t response the ground-motion characteristic from fault rupture and are insufficient for use, this two years project was proposed for developing the new attenuation relationship with localized parameter with same level so NGA’s. In the first year was to use the strong motion data from crustal earthquake in the database and base the results from NGA project to build up a ground-motion attenuation relationship for PGA and Sa that suitable for the needs of Taiwan’s engineer in earthquake assessment. In addition for increasing the usefulness of earthquake engineering, attenuation relationship for PGV, PGD and Arias Intensity will also be established in this project. In the second year, we will form a research team with Dr. Chiou in the California Department of Transportation to cooperate with PEER in the research of ground-motion attenuation relationship for subduction zone earthquake. In the period of research, we’ll discuss with the other team in NGA to promote us in participating the cooperation of international engineering technique. The result of the research will help us to improve the technique and maintain our leadership of seismic hazard analysis technique in Taiwan.