維冠大樓在0206 美濃地震中完全倒塌，造成臺灣有史以來最多人因單一建築物倒塌而罹難。探討維冠大樓在本次地震中倒塌的原因及影響因素，對未來針對此類型建築物在耐震設計規範及老舊大樓安全評估檢討上有著重要的意義。本研究著眼於研判並建立維冠大樓的破壞原因及倒塌模式，因此主要研究探討分為，(1)根據鄰近地震觀測站資料了解地震的基本性質、(2)考察維冠大樓之梁柱尺寸、電梯樓梯位置等，建立數值分析模型、(3)了解維冠大樓的基本振動特徵，並針對地震對於建築物之基本振動週期的影響進一步了解。綜合以上要點，利用歷時分析的方法，得到在本次地震作用下，維冠大樓的振動行為及研判倒塌機制，並與現場調查之結果進行比較。研究結果發現，本次地震除了對此振動週期之建築物影響較大外，結構系統不佳、軟弱層及偏心扭矩亦是造成倒塌的重要原因之一。

This paper investigates the collapse mechanism of the Weiguan building based on the Numerical Analysis. The main objective was to investigate the potential effects of partition walls that have been removed from the Weiguan building and understand the reason why it collapsed. Firstly, the earthquake information recorded from the seismic station nearby the Weiguan building was collected, and the response acceleration regarding different periods was transferred and calculated using the earthquake response spectrum. Secondly, a simulation model of the Weiguan building was established based on the floor plane and size of each structural element. The simulation model clarifies the fundamental structural period of each mode shape of the Weiguang building, therefore, indicating the influence of the response acceleration regarding different periods. Finally, time history analysis was applied to the simulation model. The vibrational characteristic of the Weiguan building was examined and compared with damage behavior that was investigated. Thus, the collapse mechanism is expected to be established.