CNT will decrease the initial and final setting times of cement.

Thank you Mr.Achyutha Kumar Reddy

https://nanografi.com/carbon-nanotubes/?gclid=EAIaIQobChMIgZC2rZ7v3QIVw8YYCh2whgkdEAAYASAAEgKyTvD_BwE

https://www.mknano.com/?gclid=EAIaIQobChMIgZC2rZ7v3QIVw8YYCh2whgkdEAAYAiAAEgK6gPD_BwE&gclid=EAIaIQobChMIgZC2rZ7v3QIVw8YYCh2whgkdEAAYAiAAEgK6gPD_BwE

Hi dear friend,

how are you?

its a very nice question

please check that links

Best regards

Amin

Dear Alizera Safari,

I think the first objective when CNTs were incorporated in cement matrix was to serve as a nano-scale fiber reinforcement. Altough there are some promising results, there is very few evidence of such behavior. An other effect that should be expected of CNT addition is an impact on the cement hydration process and hydration product formation. Since every reaction happens on surfaces, the addition of a high surface area material will obviously affect those reactions. In this case the functional groups present on CNT surface, the dimensions and morphology of CNTs and the effectiveness of dispersion will be the main variables to describe the influence. Alteration of the cement hydration products will also impact their mechanical parameters. But the alterations occure only in cement paste phase. Since in concrete you have also aggregates, the effects on mechanical behavior of the whole composite is a very complex question.

Have a look at my publications for some results on mechanical behavior of CNT-cement composites

Péter Ludvig

Thank you Mr.Ludvig

Thank you Mr.Ramezan

Cnt

1. Act as nano fibers arresting the cracks at their initial propagation.

2. Nucleation sites for the cement hydration gels helping increasing stregnth.

3. Nano fillers to the nano and microscale pores and consequently increasing the packing level of the cement matrix

Dear Muhammad S. Elfeky

In my opinion an addition of CNTs in proportions of 0,1-0,5% of cement weight do not have significant filler effect. That quantity is simply not enough to fill in pores. If any pore reduction is observed, it is rather due to the nucleation of hydration products.