Experimental study on physical and mechanical properties and micro mechanism of carbon nanotubes cement-based composites

Abstract

Carbon nanotubes are considered as a promising material for the development of high performance concrete. In order to study the effects of Multi walled carbon nanotubes (MWCNTs) content, water cement ratio and addition method on the mechanical properties and microstructure of cement-based composites, specimens with MWCNTs content of 0%, 0.05%, 0.08%, 0.10%, 0.15%, 0.20%, and 0.30% were prepared when the water cement ratio was 0.25, 0.3, 0.35, and 0.4, respectively. The physical properties, mechanical properties and microstructure were tested. The test results show that with the increase of MWCNTs content, the flexural strength and compressive strength of cement-based composites increase first and then decrease. The DIC test shows that the displacement and strain of the specimen with MWCNTs are smaller than the blank sample under the same concentrated load, while it is opposite before the failure of sample. The SEM test shows that MWCNTs play the role of bridging and filling in the matrix. The EDS analysis results show that the five main elements of carbon, oxygen, aluminum, silicon, and calcium in the composite are evenly distributed in the cement matrix.

Keywords:

• MWCNTs
• physical properties
• mechanical properties
• micro mechanism
• digital image

Acknowledgments

Authors greatly acknowledge Shandong Dazhan carbon nano technology Co., Ltd. (Shandong, China) for providing the MWCNTs.

Conflicts of interest

The authors declare no conflict of interest.

Author contributions

Conceptualization, G.L. and Z.C.; data curation, H.Z. and D.K.; resources, S.T. and Z.C.; writing—original draft preparation, G.L. and H.Z.; writing—review and editing, D.K., Z.C. and S.T. All authors have read and agreed to the published version of the manuscript.

Additional information

Funding

This work was funded by the National Natural Science Foundation of China (No. 51908075).