Increasing flexural strength and toughness of cement mortar using multi-walled Carbon nanotubes

In this study the effect of using multi-walled carbon nanotube (MWCNT) on flexural and compressive strengths, ultimate displacement and energy absorption capability of standard cement mortar considering different weight percentages of nanotubes as well as different dispersion methods has been investigated. Influential point in adding nanotubes to the composites is their proper dispersion, which is considered by comparing the results of two different dispersion methods. According to the test results and scanning electron microscope (SEM) images, the method using functionalized MWCNTs together with ultrasonication is pointed as an appropriate dispersion method. Using nanotubes resulted in significantly increase in the flexural strength and specially toughness of cement mortar which represents the ability of properly dispersed nanotubes in bridging and closure of the micro cracks. Finally, the observed results has been assessed with a statistical analysis and validated with acceptable significance levels.