EFFECTS OF MAGNETISED WATER ON THE COMPRESSIVE STRENGTH OF MORTAR

Abstract

The purpose of this paper was to investigate the influence of the magnetisation frequency (40, 80, 120, 160, 200 times) and current velocity (0.84, 1.35, 1.72 m/s) on the surface tension and contact angle of deionised water (DW) to prepare magnetised water (MW). The deionised water (DW) was treated by a self-made permanent magnet magnetiser (B=0.55 T) to prepare the MW. Then, the influence of the MW on the compressive strength and the microstructure of the mortar was investigated. The results showed that when the magnetisation frequency was 80 times and the current velocity was 1.72 m/s, the surface tension and contact angle of the MW decreased by 13.16% and 5.35%, respectively. Moreover, the magnetisation mechanism of MW could be explained by the hydrogen bond breaking in the water molecules caused by the Lorentz force. Besides, compared with the DW mortar, the 28-day compressive strength of the MW mortar increased by 6.63% due to its denser microstructure because more hydrated calcium silicate (C-S-H) and portlandite with smaller crystal sizes were generated.

Keywords

• magnetised water
• surface tension
• hydrogen bond
• compressive strength
• strengthening mechanism