Microstructure modification of cementitious composites for enhanced engineering properties using nano-graphene oxide layers
  Shamanth Gowda T. and R.V. Ranganath
  Advent of ultrafine materials of size ranging from micro to nano-meter scale with high specific surface area has created a phase shift from High Strength Concrete to High Performance Concrete (HPC). Investigations are being done on some prominent ultrafine materials such as SiO2, TiO2, AlO2, Carbon Nano Tubes (CNTs) etc, for their influence on concrete’s behaviour. Most researchers have found an improved compressive strength, enhanced tensile stress resistance as well as durability performance. Such materials are believed to alter the micro structure of concrete acting as pore fillers and arresting the crack formation and propagation at the site of crack origin. This experimental study evaluates the influence of Graphene Oxide (GO) on fresh, hardened properties and durability of cured mortar specimen up to 56 days. Samples were prepared with fixed water cement ratio of 0.5 and with varying GO addition. The design of mortar mix is based on the ‘least void percentage mix’ as per the guidelines of IS 2386. Standard sand (IS 650) of all 3 grades was used as fine aggregates. No super plasticizers were used in the mix so as to study the influence of GO alone, as a single variable. Mortar samples were tested for different physical parameters at different period of curing to notice the trend in the performance. GO in its aqueous dispersion state was used as an additive in the mix in accordance to wt% of cement used in the mix. Results reveal that the mixes with GO inclusion of less than 0.15 wt% of cement shows a better performance than the control mix in terms of compressive, tensile, flexure and water absorption indicating the influence of GO in modification of microstructure.