Mechanical properties and constitutive relation of hydrotalcite-carbon nanotube concrete

Abstract

Co-Fe-Mg-Al quaternary hydrotalcite-carbon nanotube composites (LDH-CNT composites) were prepared by co-precipitation method and blended into concrete. Universal testing machine and SHPB testing device were used to carry out static and dynamic tests on LDH-CNT concrete specimens with different LDH-CNT additions (0, 0.25 wt.%, 0.5 wt.%), and the dynamic constitutive equation was obtained according to the dynamic stress-strain curve. Results show that compared with ordinary concrete, the compressive strength and toughness of LDH-CNT concrete have been greatly improved. When the LDH-CNT composites content is 0.5 wt.%, the strength and toughness are increased by 10.8% and 16.3%, respectively; The dynamic compression mechanical properties of LDH-CNT concrete show a significant strain rate effect, and the impact compression mechanical parameters increase with the increase of the maximum strain rate. In the strain rate range of 10°∼10²s⁻¹, the theoretical curve and the measured curve fit better, and the constitutive equation can describe the dynamic mechanical response of LDH-CNT concrete.

Keywords:

• Layered double hydroxides
• carbon nanotubes
• concrete
• mechanical properties
• constitutive equation

Acknowledgements

The authors would like to acknowledge the following two platforms for support: China Nuclear Construction Key Laboratory of High Performance Concrete and Hunan Provincial Key Laboratory of High Performance Special Concrete.

Disclosure statement

The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper.

Additional information

Funding

This research was funded by the Natural Science Foundation of Hunan Province (No. 2019JJ60003).