Effects of Fiber Reinforcement on Cyclic Behavior of Dowel Bars

An experimental study is conducted to investigate the effects of steel fiber reinforcement on the cyclic behavior of dowel bars in the conditions of beam‐column interfaces. The steel fibers used in this investigation were hooked‐end with an aspect (length‐to‐diameter) ratio of 60. Four different fiber volume fractions (0%, 0.5%, 1%, and 2%) were considered. The dowel bars were grade 60 with a diameter of 1 in. (25.4 mm), and the concrete had an average compressive strength of 5.0 ksi (34.5 MPa). The cylic dowel test results indicated that dowel strength tends to increase with increase in the volume fraction of steel fibers. Steel fiber reinforcement also improved the hysteretic energy absorption capacity of the dowel mechanism, and reduced the deterioration of the mechanism under repeated cyclic deformations with relativelyl large deformations in the nonlinear range of behavior. These deformations are particularly beneficial under the effect of severe earthquake excitations.