Incorporation of a high volume of cenosphere particles in low water-to-cement matrix for developing high strength and lightweight cementitious composites

Abstract

The incorporation of a high volume of lightweight aggregates generally results in a reduction of mechanical properties. To overcome this intrinsic problem, this study used a high volume of cenosphere particles (10–20 wt.% of cement) along with silica fume and quartz powder in a very dense microstructure. The reactivity of the cenospheres in the composites was investigated by X-ray diffraction and thermogravimetric analysis. Furthermore, microcomputed tomography was used to visualize the cenosphere particles in the designed cementitious composite for ensuring uniform distribution. The experiments showed that compressive strengths of 64–74 MPa and 87–90 MPa at 28 days of curing were achieved under ambient (20 °C) and high (90 °C) temperature, respectively. Furthermore, it exhibited significantly low density and thermal conductivity compared to other cementitious composites with cenospheres. Finally, the role of the cenospheres in the designed cementitious matrix was limited to inert filler, and no direct evidence of a chemical reaction was observed.

Keywords:

• Lightweight concrete
• cenospheres
• thermal conductivity
• microcomputed tomography
• segregation

Disclosure Statement

No potential conflict of interest was reported by the author(s).

Additional information

Funding

This work is supported by the Korea Agency for Infrastructure Technology Advancement (KAIA) grant funded by the Ministry of Land, Infrastructure and Transport (Grant 22NANO-B156177-03). The Institute of Engineering Research at Seoul National University provided research facilities for this work.