Behavior of Reinforced Concrete Building Frames Subjected to Elevated Temperature-Behavior of Ordinary Concrete Beam

• Main Authors: Po-sheng Chiu, 邱柏昇
• Other Authors: I-kuang Fang
• Format: Others
• Language: zh-TW
• Published: 2009
• Online Access: http://ndltd.ncl.edu.tw/handle/30266001095351421865

碩士 === 國立成功大學 === 土木工程學系碩博士班 === 97 === At present, reinforced concrete is the main building construction material. The research on the beam-column subassemblages subjected to fire is still very limited. This experimental study aims at the behavior of beam-column subassemblages during the preheating, heating, and residual srength tests. Three full scale beam-column sub-assemblages specimens were tested. This study is focused on the behavior of NC5 specimen made of nornal concrete. The analytical study is carried out using the ANSYS software to predict the temperature distribution in beam section and deformation of beam-column sub-assemblage under elevated temperature. The predicted and measured results were compared. The primary results are summarized as follows: 1.The temperature will be sluggish increasing as the inner temperature of the specimen reached about 100℃, which is due to the phase change of inner pore water of concrete. 2.The comparisons of predicted and measured temperature show that using ANSYS software and thermal properties of concrete suggested by EC2 can give reasonably good results. 3.Under the service load and ISO 834 thermal action for 150 minutes, the variation of maximum deflections at △1, △m and △2 for NC5 beam are 47.4 mm, 58.62 mm and 65.43 mm, respectively, during the heating and cooling stage. 4.When the total beam load reached approximately 465 kN during the residual strength test, the concrete crushed at the edge of loading plate of P2. The corresponding maximum deflections atΔ1, Δm and Δ2 were 63.41 mm, 117.21 mm and 121.24 mm, respectively. The curvature ductility of the section at P2 is 7.83 according to the measured average strains at top and bottom of the section.