THE FAILURE MODAL ANALYSIS OF FULL-SCALE HIGH STRENGTH CONCRETE FRAME COLUMNS WITH HIGH AXIAL COMPRESSION RATIOS

In order to research the aseismic behaviors of full-scale high-strength concrete(HSC) frame columns, the crack distributing and developing rules, failure mechanisms and modes were discussed and analyzed by the basis of experimental study of 9 full-scale HSC rectangular frame columns with high axial compression ratios, high-strength longitudinal reinforcements and transverse reinforcements and rectangular interlocking ties. The main results indicate as follows. The cracking lengths of full-scale HSC columns are longer; the cracks occur abruptly; the cracks distribute densely as the axial compression ratios are lower, and they distribute sparsely as the axial compression ratios are higher; the concrete spalling degrees are severely; the axial compression ratios, the strength grades of concrete and the spaces of transverse reinforcements are the main influencing factors on the failure modes of frame columns; the influencing factors of the modes and ratios of transverse reinforcements (or transverse reinforcement characteristic values) on the failure modes of frame columns are smaller; the larger sectional dimensions and length breadth ratios are, the more seriously the specimens destroy.