Paper Title
Effect of Addition of Multiwalled Carbon Nanotubes on Setting Time of Cement- CNT Composite

Abstract
Background/ Objectives and Goals To meet the increasing advancement and speed of construction technology there certainly is a need of improvement in the performance of the core of the technology that is; cement. Different additives have been used throughout the world to improve certain properties of cement like strength, limited shrinkage or expansion and initial and final setting time. Methods The present study is sought to analyze the behavior of Commercial grade Portland cement (IS 1489) over the Standard consistency, Initial setting time and Final setting time as a result of addition of MWCNTs as prepared by N-CODF method using domestic LPG as fuel and oxygen as an oxidizer. The experiment was carried out over an addition of 0.1% MWCNTs into OPC by physical blending method (PBM). Dispersion of MWCNTs, which is the key parameter, was carried out using ultasonication. Standard consistency and setting times were determined using Vicat’s apparatus according to standardized methods. Expected Results/ Conclusion/ Contribution The observed decrease in initial and final setting time of OPC after addition on MWCNTs was 18.18% & 21.63% respectively. With the addition of 0.1% MWCNTs, the standard consistency has reduced from 36% to 34%. This decrease in standard consistency and setting time of cement–CNT composite can be attributed to the fact that porous structure of cement resulting from hydration has been filled with MWCNTs used. Addition of MWCNTs increases hydrophilicity of cement due to adsorption of water molecules in MWCNTs because of the capillary action. Keywords - Carbon Nanotubes, CNT- Cement composite, setting time