本研究以中央氣象局地震監測系統在全台各定點站接收的資料，進行強地動資料之分析。首先簡介台灣地理環境與車籠埔斷層之概況，對集集地震台灣各地場址、地震譜、地動參數與其衰減律作一回顧。接著以Fortran語言撰寫資料處理所需之計算機程式GMA(Ground Motion Analysis)，該程式內含基線修正(Baseline Correction)、數值積分(Numerical Integration)、強震參數(Ground Motion Parameters)(共15個)計算、線性反應譜(Linear Response Spectrum)、富氏振幅譜(Fourier Amplitude Spectrum)、功率譜(Power Spectrum)、振幅概率密度譜(Probability Density)、運用Newmark法的滑移量積分(Newmark Integration Method)等副程式。非線性反應譜(Nonlinear Response Spectrum)的部分以商用程式BISPEC執行。從時間域和頻率域分析集集地震台灣各地區受地震作用下地盤的振動反應，比較NS、EW及UD三個方向之地動內涵，並呈現地動參數之衰減律、Newmark滑移量與近斷層效應之分析。 計算機程式GMA將各類地震譜與地動參數之數據輸出至Excel檔案，並將資料繪圖，不僅增加本研究之便利性，可協助往後地震工程研究者資料處理的效率。 This paper analyzed the strong ground motion characteristics of the 1999 Chi-Chi earthquake using TSMIP (Taiwan Strong Motion Instrumentation Program) records. First, the geologic environment and Che-Long-Pu fault in Taiwan were introduced, and the literatures on earthquake spectrum, ground motion parameters and its attenuation characteristics of the Chi-Chi earthquake were summarized. Then, the computer program GMA (Ground Motion Analysis) developed by FORTRAN was used to carry out the analysis work. The program consists of many calculation functions, such as baseline correction, numerical integration, ground motion parameters calculation (15 parameters totally), linear response spectrum, fourier amplitude spectrum, power spectrum, probability density spectrum and Newmark residual displacement integration. The nonlinear response spectrum was calculated by the commercial program BISPEC. The ground motion characteristics of the Chi-Chi earthquake was analyzed in time and frequency domains and in three different directions (NS、EW and UD). The results of analysis also showed the ground motion attenuation, Newmark sliding analysis and the near-fault effect. The computer program GMA can output many kinds of earthquake spectrum data and ground motion parameters as Excel file and it can plot these data in the sheets of the Excel file. The GMA makes the analysis very convenient and fast, therefore it will benefit the people who need to process the earthquake ground motion data.
