| Title |
Evaluation of Fire Resistance Performance of Reinforced Concrete Column Member using High Strength Concrete by Loading and Unloading Test |
| Authors |
Ryu Dong-Woo ; Song Young-Chan ; Lee Jong-Chan ; Lee Sea-Hyun ; Min Byung-Yeol |
| Keywords |
High Strength Concrete ; Reinforce Concrete Column ; High Temperature ; Spalling ; Fire Resistance Efficiency ; Loading Test ; Unloading Test |
| Abstract |
Amidst increasingly rising skyscrapers, higher than 30 stories, the concrete also tends to be strengthened day by day. Then the high strength concrete becoming more popular for the high-rise buildings, when exposed to high temperature heat in fire, has caused sectional damage to the structure, thereby resulting in deterioration of bearing capacity since the reinforcement is directly exposed to high temperature, and likely having impact on structural stability of the building. However, according to current laws and regulations, reinforced concrete structure are designated as fire-resistance structure as long as they maintain a certain level of thickness (25cm in diameter for column structure), irrespective of type of concrete material (standard or high strength), and it doesn’t require any separate fire resistance test. Thus it’s questionable, if they substantially meet the performance requirements as a fire resistance structure, depending on use and material of structural members. The study hence was intended to evaluate and compare the fire resistance efficiency of high strength concrete after assembling the column specimens with the same mixing ratio and conducting the loading and non-loading tests in accordance with ISO 834 standard fire heat curve. Furthermore, they were compared with non-loading test in small scale conducted using a floor heat furnace available in domestic labs in a bid to present the basic data for evaluating the fire resistance of concrete column. The fire resistance test result is described as follows. 1) Explosive spalling on high strength concrete started in 7 minutes after heating and lasted fro 30 minutes. 2) As a result of comparing the time for fire resistance at the loading test and unloading test, unloading test was found to be disadvantageous in destruction and deflection test. 3) Domestic unloading test was found to have been in between Japanese loading test and unloading test. |