Sabry Fayed, Emrah Madenci, Yasin Onuralp Özkiliç, Mohamed H. Zakaria
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引用次数: 0
Abstract
In this study, the experimental findings of twenty pull-out tests on the bond efficiency of threaded/ribbed steel rods used in near-surface mounting (NSM) are presented. On a groove (20 × 20 mm) that was slotted in one of the sides of a concrete block measuring 250 × 250 × 200 mm, a pull-out experiment was performed. The primary factors are the slot-filling materials (substrate concrete and epoxy paste), bonded length (equal to 5, 7, 10, and 15 times the rod diameter), surface pattern conditions (conventional ribbed reinforcing rebar and threaded bolt), use of nuts or rings welded at the free end of the bonded length, and use of straight or spiral wire welded along the length of the bonded length. The tested specimens' ultimate bond strength, slip, bond stress–slip response, failure patterns, stiffness, and ductility are recorded and assessed. The results showed that the ultimate bond strength and corresponding slip of ribbed rods cemented with epoxy were higher by 11.11% and 199%, respectively, than those of ribbed rods submerged in the substrate. Over the controls, all NSM epoxy-rods exhibited a greater ductility. As the bonded length increased, the ultimate bond strength of NSM rods fell by 12–32%. As the bonded length increased, the stiffness decreased. On the other hand, the ductility of NSM epoxy-rods increased as the bonded length increased. All applied schemes such as nuts, rings, longitudinal bars, and spiral bars significantly improved the ultimate bond strength (maximum = 25.93%) and corresponding slip (maximum = 166.67%) of NSM threaded rods as compared to the control ones.
期刊介绍:
The International Journal of Concrete Structures and Materials (IJCSM) provides a forum targeted for engineers and scientists around the globe to present and discuss various topics related to concrete, concrete structures and other applied materials incorporating cement cementitious binder, and polymer or fiber in conjunction with concrete. These forums give participants an opportunity to contribute their knowledge for the advancement of society. Topics include, but are not limited to, research results on
Properties and performance of concrete and concrete structures
Advanced and improved experimental techniques
Latest modelling methods
Possible improvement and enhancement of concrete properties
Structural and microstructural characterization
Concrete applications
Fiber reinforced concrete technology
Concrete waste management.