在工程應用上，發展地震危害度分析之震度衰減關係對地震災害防治是一個非常有用的方法。，因此本研究將利用中央氣象局台灣強地動觀測計劃(Taiwan Strong Motion Instrumentation Program, TSMIP) ，從1993年到2008年蒐集到的強震記錄探討台灣最大地表加速度(Peak Ground Acceleration, PGA)之衰減，包括水平向（兩水平向幾何平均）和垂直向PGA。PGA衰減非常複雜，影響的因素非常多，例如：震源特性、從震源到場址地震波的衰減、場址的土壤特性等。若以全台灣為範圍發展PGA衰減模式，由於範圍太大，PGA衰減之預測準確度將會較差。改善PGA衰減之預測準確度的一個可行方法是將台灣分成幾個小的區域，再發展各個分區的PGA衰減模式。本研究將比較不同分區的PGA衰減模式。此外，規模大小不同地震的PGA衰減模式可能也有差異，因此本研究將比較規模ML<6和ML≥6地震記錄之PGA衰減模式。研究成果可提供給工程界參考或災害潛勢分析應用。 In engineering applications, the development of attenuation relationships in a seismic hazard analysis is a useful way to plan for earthquake hazard mitigation. This study developed new PGA attenuation models in Taiwan, including horizontal (the geometric average of two horizontal PGA) and vertical PGA attenuation models by using strong motion data from 1993 to 2008 collected by Taiwan strong motion seismic network. PGA attenuation is very complicated because it is affected by many factors, such as the characteristics of seismic source, attenuation of seismic waves from the seismic source to a recording site, and soil characteristics at the recording site. Therefore, we believe that a feasible way to enhance the accuracy of predicted PAG attenuation in Taiwan is to separate the Taiwan into several smaller areas, and then develop peak ground motion attenuation model for each area. PGA attenuation models in different areas in Taiwan were compared in this study. In addition, PGA attenuation models for earthquakes with different magnitude may be different. Therefore, PGA attenuations for earthquakes with magnitude ML <6 and ML ≥ 6 were also compared in this study. Research results can be offered to engineering application or disaster potential analysis.
