OUT-OF-AXIS DEFORMATION AND SLIP OF HOOKED DEFORMED BARS

Abstract

  The enlargement of amount of reinforcement causes a problem that anchoring bar can not be arranged as design code provides in recent years. One of solutions for that problem will be establishment of a performance verification design method for anchoring bars. This verification method needs a local bond stress-slip model of hooked bars. The local slip of hooked bars will be affected by out-of-axis deformation of the bar. Therefore, the out-of-axis deformation and additional local slip by that deformation were investigated. The additional local slip caused by out-of-axis deformation was almost the same amount as the slip by elongation of straight bars in 90 degree hooked bar and 1.5 times of that elongation slip in 180 degree hooked bar. Total local slip just before yielding of bar was 1.8 times of the slip of straight bars in 90 degree hooked bars and 2.6 times of that in 180 degree hooked bar.