•  
  •  
 

Article Type

Article

Abstract

This research is devoted to investigating the experimental and theoretical behavior of hybrid deep beams under monotonic and repeated two-point loading. The dimensions and the flexural reinforcement of the deep beams were kept constant. In this work, the idea of a hybrid beam is completely different. Two types of concrete were used but not in the cross-section. The first type, which is fiberous concrete (FC), was used in casting beam sides (shear spans), while the second type was conventional concrete (CC) which was used in the middle portion of the beam (between two shear spans). This was done to strengthen the deep beam sides (shear spans) against cracking due to shear (diagonal strut) failure. The experimental program includes casting and testing of 4 deep beams, one of them is tested as a control beam under monotonic loading and the others were tested under repeated loading at levels of 90%, 70%, and 50% of the ultimate load of its control beam. The effect of loading type is studied for constant steel fiber (SF) ratio and the amount of web reinforcement. The ultimate load decreases when beams are subjected to repeated loading of different levels. A comparison of experimental results was made with corresponding predicted values using the Strut and Tie procedure presented in Appendix A of ACI 318M-11 Code and with other procedures mentioned in the literature. It was found that the Strut and Tie procedure presented in Appendix A of ACI 318M-11 Code gives conservative results compared with the experimental tested results.

Keywords

Deep beam, Hybrid, Repeated loading, Strengthening, Shear spans.

Download

Share

COinS