本研究之目的為利用數值模擬方法，配合國外學者已發表之實驗數據，分析火害中梁與柱構件的強度歷時變化，評估其耐火時效，進而應用在分析梁柱複合構件於火害中強度變化情形。
分析方法：1、使用ANSYS套裝軟體模擬混凝土斷面在遭受標準升溫曲線的火害下，各時間點的溫度分佈，並與CEB-FIP提供之數據相印證，2、梁、柱構件遭受標準升溫曲線的火害下，分析火害中梁柱構件的強度歷時變化，進而評估其耐火時效。
使用ANSYS軟體進行熱傳分析，得到之溫度歷程與CEB-FIP提供之數據極為接近。模擬無偏心加載之柱構件，預壓力介於0.1~0.4fc'之間及模擬有偏心加載之柱構件，偏心距介於柱邊長的1/20~1/2時，皆可有效預測耐火時效。模擬連續梁時，當破壞發生在正彎矩處，其分析值與實驗值非常接近；破壞發生在負彎矩處時，耐火時效皆低於實驗值。

關鍵詞：耐火時效，ANSYS，梁柱構件

This paper employs a numerical method to evaluate the fire resistance reinforced concrete beams and columns under elevated temperature. The analytical results were then compared with the existing experimental data.
There are two parts of analysis. First, ANSYS program was used to determine the temperature distribution in a reinforced concrete section subject to standard temperature condition, and the analysis was compared with the existing data of CEB-FIP report. Second, considering the deterioration of material under fire damage, the fire resistance of reinforced concrete columns and beams was assessed according to the standard temperature condition.
The results show that the temperature distribution in a reinforced concrete section analyzed by ANSYS program was close to the data of CEB-FIP report. The numerical analysis can reasonably predict the fire resistance of concentrically loaded columns with fc=0.1~0.4fc' and eccentrically loaded columns with the eccentricity varying from 1/20~1/2 times of the long side of column section. For the validation of continuous beams, the strength predictions in the sagging region were more accurate than those in hogging region.

Keywords : fire resistance, ANSYS, reinforced concrete

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