콘크리트가 충전된 강관 합성기둥은 화재 시 내부 콘크리트가 내력을 견딜 수 있어 높은 하중을 받는 건축물에 적용되고 있으나 높은 내화성능을 요구하는데 반해 이를 평가할 수 있는 방법은 제한되어 있다. 본 논문에서는 폭 700mm 이상인 무피복 대형합성기둥의 온도분포를 확인하기 위해서 수평가열로에서 3시간 내화실험을 수행하고 이후에 압축실험에 수행하여 잔존내력을 확인하였다. 실험 결과 3시간의 화재 노출 후에 폭 700mm 대형합성기둥은 57%의 잔존내력을 가지는 것으로 나타났으며, 재료의 화재 강도저감만을 고려한 잔존내력 예측은 내력을 낮게 평가하는 것으로 나타났다.

This study develops numerical model of mega composite columns in fire and investigates the residual areas using 500℃ isotherm method and residual capacity of mega composite columns after 3 hours. In order to perform heat transfer analysis, thermal properties of steels and concrete were adopted from Eurocodes. In addition to, the temperature distributions of composite columns with respect to fire tests were compared with numerical analysis results. As a result, residual capacity of mega composite column with 1m width remained more than 45%. The residual capacity of mega composite column was only increased to 2.3∼2.6% with the use of additional rebars.

Deep Deck plate is suitable to long span structures because it has larger flexural rigidity than other shape deck plate. but Deflection is critically proportional to span length than other factors. and large deflection makes works anxiety and possibility of structural problems high after casting concrete. to overcome these problems, Preload is introduced to control the deflection of deep deck plate that ha s long span. So in this study, residual strength of preloaded deep deck plate is evaluated by FEM analysis method. for this study 4 analysis models is used and have each preload. Target preload for analysis models is when deck plate cambered to 30mm. 0.0, 0.8, 1.0, 1.2, times of target preload are applied to each analysis models. In result of analysis, Preload influence residual strength of deck plate. And much preload degrade strength of deck plate.