Effect of graphene oxide and functionalized carbon nanotubes on mechanical and durability properties of high volume fly-ash cement nanocomposite

Abstract

In the current investigation, the effect of Graphene Oxide (GO) and Functionalized Carbon Nanotubes (FCNTs) on the mechanical and durability properties of High Volume Fly-ash (HVFA) cement nanocomposite. The two control samples are fabricated including OPC-C and HVFA-C, whereas, the GO (0.005, 0.01, 0.02, and 0.04% by weight of binder) incorporated samples are called HVFA-GO-CNCs and for FCNTs (0.005, 0.01, 0.02, and 0.04% by weight of binder) incorporated samples are named as HVFA-FCNT-CNCs. It was observed the addition of 0.02% GO and 0.02% FCNTs in HVFA cement nanocomposite improved compressive (37.21, 27%) and tensile strength (61.71, 41.93%) as compared to the control (HVFA-C) at a curing age of 90 days. Electrical resistivity for all mixes of HVFA-GO-CNCs has been increased with increasing dosages of GO, while in the case of HVFA-FCNT-CNCs decreased with increasing dosages of FCNTs. The capillary water absorption test results observed that incorporating the GO and FCNTs into the HVFA cement nanocomposite decreased water absorption with increasing dosages of GO and FCNTs. After acid attack on HVFA-GO-CNCs and HVFA-FCNT-CNCs, compressive strength was decreased and after sulphate attack on HVFA-GO-CNCs and HVFA-FCNT-CNCs, compressive strength was found to be increased as compared to water cured sample, at 90 days of curing. In this study, GO significantly improves compressive, tensile strength, apparent electrical resistivity, reduces capillary water absorption, and more resistant to acid/sulphate attack of HVFA cement nanocomposite as compared to the FCNTs. So, the current study provides a suitable path for the production of eco-friendly, cost-effective, better mechanical properties, and more durable building materials.