Bond Behavior of High Performance Reinforcing Bars for Concrete Structures

Bond between the concrete and the reinforcing steel is a major factor affecting the performance of reinforced concrete structures. Advances in material science led to the production of High Performance Steel that has enhanced corrosion resistance and higher strength compared to conventional Grade 60 steel. Such material can lead to more economical design reducing the material requirements for a particular project and expanding its life span. The objective of this research is to study the bond behavior of High Performance reinforcing bars for concrete structures and to evaluate the effect of different parameters believed to affect the bond characteristics. Twenty-two large scale reinforced concrete splice beams were constructed using No.8 and No.11 reinforcing bars, having different cross-sections with varying concrete compressive strengths and development lengths. The beams were tested using four point bending setup to provide a constant moment region over the splice zone. Test results indicate that stresses up 90 ksi can be achieved in the No.8 bars and up to 70 ksi in the No.11 bars without confinement; however, it is recommended to use transverse reinforcement to confine the High Performance bars in order to ensure ductility. These stresses can be evaluated at failure using a simple proposed equation. Test results were used to extend the current ACI Committee 408 equations to better predict the stresses in the High Performance Steel.

Author dc:creator

• Hosny, Amr

Advisors dc:contributor.advisor

• Dr. Sami Rizkalla, Committee Chair
• Dr. Emmett Sumner, Committee Member
• Dr. Vernon Matzen, Committee Member

• Reinforced Concrete
• High Strength Steel
• High Performance Steel
• Bond

Statement dc:rights

• I hereby certify that, if appropriate, I have obtained and attached hereto a written permission statement from the owner(s) of each third party copyrighted matter to be included in my thesis, dis sertation, or project report, allowing distribution as specified below. I certify that the version I submitted is the same as that approved by my advisory committee. I hereby grant to NC State University or its agents the non-exclusive license to archive and make accessible, under the conditions specified below, my thesis, dissertation, or project report in whole or in part in all forms of media, now or hereafter known. I retain all other ownership rights to the copyright of the thesis, dissertation or project report. I also retain the right to use in future works (such as articles or books) all or part of this thesis, dissertation, or project report.

Dc Identifier Other

etd-04222007-211818

OAI record oai:identifier

https://repository.lib.ncsu.edu/server/oai/request?verb=GetRecord&metadataPrefix=dim&identifier=oai%3Arepository.lib.ncsu.edu%3A1840.16%2F2207