Unlocking the potential of carbon nanotubes and nano clay in concrete: assessing the bond strength and failure modes.

Document Type : Research articles

Authors

1 National Research Centre, Giza, Eygpt

2 Department of Civil Engineering, Faculty of Engineering at Shoubra, Benha University, Cairo, Egypt.

Abstract

Nano technology has emerged as a prominent field in civil engineering, particularly in the realm of concrete construction, offering immense potential for improving material properties. This study aims to investigate the influence of hybridized carbon nanotubes (CNTs) and nano clay (NC) on the bond strength, failure modes. To determine the optimal ratio, CNTs were replaced at levels of 0.01%, 0.03%, and 0.05%, while NC was maintained at 3%. Additionally, the combination of CNTs and nano clay in hybrid mixes improves bond strength significantly. In the case of cement content samples with 400 kg/m3, the optimal ratio of 0.05% CNTs resulted in improvements of 107.2% and 92.5% at 10mm and 12mm rebars, respectively. Additionally, the same ratio gains 3.4% and 31.4% for cement content of 550 kg/m3 for 10mm and 12mm rebars, respectively. At rebar 16mm, the optimal ratio is 0.03% CNTs, with an improvement in results of 120.34% and 110.4% for cement content of 400 and 550 kg/m3, respectively. Mixtures with a ratio of 0.03% CNTs + 3% NC exhibit gains of 174.9% and 76.8% for bond strength test rebars 10mm and 12mm, respectively, for cement content 400 kg/m3. For a cement content of 550 kg/m3, the optimal ratio is 0.03% CNTs + 3% NC. The increase in bond strength is 42% and 66% for rebars 10mm and 16mm. But, at rebar 16mm, the optimal ratio is 0.01% CNTs + 3% NC; the increase is 109.96% and 75.9% for cement content of 400 kg/m3 and 550 kg/m3 respectively.

Keywords