| Column bases are important joints to connect the main structure to the basement in steel structures. It is the primary factor to determine the capacity of stability and plays an important role in structures. Columns can be effectively fixed by the column bases and their axial force, shear force and moment can be passed to the basement through the column bases, as a result, the main structure can be connected to the basement effectively.As the CFT (Concrete-Filled steel Tube) being used more and more widely nowadays, the CFT column bases are nothing new, but their performance are still not known very well. Therefore, it is necessary to do some research to make it clear.Based on a hysteretic test of a normal semi-embedded CFT column base and an FEM analysis as well, this paper made some analysis and research to recognize the rigidity, ductility, capacity and mechanism of this type of column base. Then some conclusions and predictions about the performance of column bases were made based on the results of tests and FEM analysis, and some suggestions for engineering design were given as well. Beside this, a new type of column base was presented in this paper which is semi-embedded CFT column base reinforced by central reinforcing bars. One test of this new type was carried and then the comparison between the performance of the normal type and the new one was made. Finally, the influence of the central reinforcing bars over the performance of column base was recognized.Beyond the above, the estimation of the capacity of column bases subjected to combined axial compression and bending was discussed, and some advice was given as well. |
PDF Full Text Request