The Study of Physical and Thermal Conductivity Properties of Cement Paste Containing Nanosilica

Abstract:

This research was presented the physical and thermal conductivity properties of cement pastes containing nanosilica by mixing three nanosilica particle sizes of 12, 50 and 150 nm, using nanosilica of 1-5 wt%. The water-cementitious ratio (W/C) was 0.5 for all samples. Thermal property coefficients were tested using a direct measuring instrument with surface probe (ISOMET2114). The influence of nanosilica on the physical properties were compressive strength, bulk density, XRD and SEM respectively. The results indicated that the use of nanosilica as an admixture can reduce the thermal conductivity and lowered the bulk density of specimen. The cement paste with nanosilica particle size of 50 nm with 4 wt% nanosilica at the age of 28 days showed the optimized properties. The thermal conductivity was lowest at 0.913 W/m-K, the compressive strength was highest at 51.62 MPa and the bulk density was 1,806 kg/m³ respectively. The compressive strength increases more than 50% higher than that of pure paste. The cement pastes with nanosilica particle sizes of 50 and 150 nm, have lower unit weight and thermal conductivity than typical control cement paste about 9% and 15% respectively. The nanosilica mixed cement paste is very interesting for energy saving when used as wall insulating material.

• Periodical: Key Engineering Materials (Volume 659)
• Pages: 164-168
• DOI: https://doi.org/10.4028/www.scientific.net/KEM.659.164
• Online since: August 2015
• Authors: Pongsak Jittabut, Prinya Chindaprasirt, Supree Pinitsoontorn
• Keywords: Cement Paste, Nanosilica, Physical Properties, Thermal Conductivity

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