Experiments On Seismic Behavior Of Concrete Short Columns With HRB600 High-stregth Stirrups

With the progress of technological and the development of high-rise and large span building structure,there are great economic and social benefits in the research of high strength building materials.Improving the strength grade of the steel bar can not only make the mechanical performance of the structure better,make the safety of structure improved,but also make the amount of steel reduced,geting obvious economic and social benefits.In practical engineering,because of the limit of the axial compression factor of the high rise structure bottom column,it has to be designed into short column or ultra short column,and the earthquake damage before shows that the short column is brittle shear failure,which belongs to brittle failure.Carrying out high-strength stirrup confined concrete short columns seismic test research,will provide the basis for experimental and theoretical research on China’s high strength reinforced application.11 high-strength concrete short-columns confined with high-strength stirrups were designed for the anti-seismic behavior,which were used to study the process and mode of component failure,hysteretic characteristics,capacity,energy dissipation and analyze ductility performance of columns,focus on the analysis of the stirrup stress and stirrup confinement on the concrete effect.Design parameters include stirrup strength,stirrup spacing,stirrup diameter,axial compression ratio,stirrup form.The result indicated that: The failure mode of concrete short columns with HRB600 high strength stirrup are flexure shear failure.Axial compression ratio is one of the most important factors affecting the seismic performance.In the high axial compression ratio,concrete short columns with compact HRB600 high strength stirrups still have good ductility and energy dissipation capacity.The difference between the seismic performance of shape of cassion and octagon and the hoop is not much,but the seismic performance of the rectangular stirrup is much worse than the two before.There is a little difference between the bearing capacity of the concrete specimens with different stirrup that parameters in a certain range.In the high axial compression ratio,the stirrups has yielded when the component with compact stirrups failed.The high strength stirrups in mostconponents yielded in Displacement control stage.This shows that concrete short columns with high strength stirrup has good deformation capacity and carrying capacity of collapse body.