A study of tie confined fiber reinforced concrete under axial compression

Abstract

An experimental investigation on the behavior of tie confined fiber reinforced concrete (CFRC) has been carried out. The compressive strength of FRC depends on both the volume fraction (V.) and aspect ratio (l / dl of the fibers, a common parameter, which combines these two effects, is used ln the form of reinforcing index, Rl (product of weight fraction and aspect ratio). The palmary variables considered in this study are: (l) Five values of confinement Index (C,) (Viz., O.O, O.O8, O.19, O.3 and 0.56) and (ii) Five values of volume faction of fibers, Oo/o, O.3%, 0.6%, O.9Vo and 7..2% (yrz., reinforcing index values 0, O,74, 1'.47, 2.27- and 2.95 respectlvety), A total of 90 specimens of concrete prisms of size 15O mm X 15O mm X 3OO mm were cast and tested undel strain control rate of loading. The test results level that the ductile characteristics of FRC are further improved due to tie confinement and also improved the peak stress, stain at peak stress and ductility of concrete. The improvement ls In proportion to the Rl of the fiber for a given confinement index (C,) of the lateral reinforcement