| Summary: | 碩士 === 國立成功大學 === 土木工程學系碩博士班 === 95 === The performance based fire resistant codes are the focused topics being studied and developed worldwide. The available test results are primarily based on the single small scale specimens. Tests on the large scale beam-column assemblage are still very limited. More study is still needed for reinforced concrete buildings subjected to the elevated temperature. This research aims at the validation for the fire resistance of a seven-story residential reinforced concrete building designed by the current building code. The features include the deformation characteristics, damage state observation, and residual strength during the tests of elevated temperature and cooling stages as well as the post fire condition.
In the analytical work, the ANSYS program was used to predict the temperature distribution at the inside of the cross section and compare with the test results. In the experimental work, a full scale beam-column sub-assemblage SCC1 was tested in room temperature, and a separate identical specimen SCC2 was tested in elevated temperature for the comparison of the deformations and residual strength. The elevated temperature test followed the ISO 834 time-temperature curve and took three hours.
The primary differences in the behavior of SCC2 and SCC1 specimens are the flexural stiffness and failure load. Linear load-deflection behavior was observed in specimen SCC2 up to the load level of 2.5 times of the service load. The total loads on specimen SCC2 was about 0.84 times of those at service load condition. After three hours of elevated temperature test, the increases in the vertical deflections of load points of specimen SCC2 were about 52.2 mm to 66 mm which was about 12 times of the deflections in the room temperature. The residual deflections, after 15 hours of cooling, were about 41 to 46 mm, which was about 8 -10 times of the deflections in room temperature.
The measured temperature at the corner of stirrup after three hours elevated temperature test was about 500-600℃, at the corner flexural reinforcement was about 650℃, and at the center of the cross section was about 110-120℃. Using the ANSYS program incorporated with the thermal properties of Ellingwood can reasonably predict the temperature distribution of the cross section.
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