FIRE RESISTANCE DESIGN OF CIRCULAR STEEL TUBE CONFINED REINFORCED CONCRETE COLUMNS
Hua Yang 1, 2*, Faqi Liu1, 2, Yuyin Wang 1, 2 and Sumei Zhang 1, 2
1 Key Lab of Structures Dynamic Behavior and Control of the Ministry of Education, Harbin Institute of Technology, Harbin, China
2 Key Lab of Smart Prevention and Mitigation of Civil Engineering Disasters of the Ministry of Industry and Information Technology, Harbin Institute of Technology, Harbin, China
No study has been reported on fire performance of steel tube confined reinforced concrete (STCRC) columns. Hence fire behaviour of circular STCRC columns is investigated in this paper. Fire tests and numerical studies of circular STCRC columns are briefly introduced. Five full-scale specimens, including four circular STCRC columns and one CFST column, were tested to failure under combined thermal and mechanical loading. Temperatures across the section, displacement versus time curves and fire resistance of these columns were monitored and recorded. A finite element (FE) model was developed using the program ABAQUS, and validated against the test results. Based on test and FE results, a simplified design method was proposed for predicting fire resistance of circular STCRC columns exposed to ISO 834 standard fire condition. It was found that load ratio has significant influence on the fire resistance of circular STCRC columns. Compared with CFST columns and reinforced concrete columns, circular STCRC columns have higher fire resistance than the former and lower fire resistance than the latter.
Circular steel tube confined reinforced concrete column; Fire safety; Test; Simulation; Design method