83 / 2022-04-15 16:48:06

Bond properties of deformed steel bar with geopolymer incorporating multi-walled carbon nanotubes under monotonic load.

Bond properties,Bond stress-slip model,Deformed steel bars,Engineering Geopolymers Composites

Geopolymer is a kind of green and environment-friendly cementing material. The bond between steel bar and geopolymer is an important factor to determine the mechanical properties of geopolymer structure under static and dynamic loads. In this paper, the local bonding properties of steel bars in geological polymers were studied experimentally. The monotonic loading tests of 120 specimens were carried out by using the central tensile test method. The main variables include the volume content of PVA fiber, the diameter of special-shaped steel bar and the Anchorage length of steel bar. The results show that compared with the specimens without PVA fiber, the bonding property between geopolymer and steel bar is significantly improved by the addition of PVA fiber. Among the specimens mixed with PVA fiber, the bond strength of the specimen with 2% volume fraction of PVA fiber is the lowest, but these specimens have the best energy dissipation performance under large slip. In addition, the increase of special-shaped steel bar diameter and Anchorage length is not conducive to the improvement of peak bond strength and energy dissipation capacity in the process of steel bar pull-out. Finally, a mathematical model of bond stress-slip relationship is proposed, which is suitable for the bond-slip curve of geopolymer and steel bar.