ANALYSIS OF THE INFLUENCING FACTORS FOR THE SHEAR-BOND FAILURE OF RC COLUMNS

Shear-bond failure of reinforced concrete columns is a common form of the earthquake damage. And RC columns of this failure types have fast stiffness degradation, poor ductility. The hysteresis loops pinch obviously and the energy dissipation capacity is poor. Therefore, it is necessary to further research on the effect factors of shear-bond failure of reinforced concrete columns to avoid the occurrence of such damage. The effect factors on the failure modes of RC columns such as stirrup ratio, concrete strength, axial compression ratio, shear span ratio, the diameter of longitudinal bar and the loading mode are analyzed by the results of test and finite element simulation. The results indicate that the conditions of RC columns, which are easy to failure under shear-bond failure mode, are as follows: larger stirrup ratio, lower concrete strength grade, axial compression ratio 0.1#x02264;n#x02264;0.5, shear span ratio 1.25<#x003bb;<2.5, larger reinforcement ratio and reinforcement bar diameter and the cyclic loading.