Effect of chloride ion bonded ceramic sand with bishell structure on the properties of sea sand mortar
WANG Peng
YAN Jianhua
DU Jiajun
Abstract：In order to control the harm of internal chloride ions in concrete,this paper studies the core-shell structure chlo-ride ion bonded ceramic sand,and uses nano-silica(NS)cement slurry to wrap core-shell structure ceramic sand to form double-shell structure chloride ion bonded ceramic sand,and studies its effect on controlling the outward migration of bonded chloride ions in the ceramic sand.Firstly,Fe2O3,Ca(OH)2 and Al2O3 were prepared as the core material,red mud,fly ash,clay and quartz as the shell material,and the ceramic sand(referred to as CAF ceramic sand)was fired at 1200℃ and 1 h.When CAF ceramic sand(referred to as CAF1 ceramic sand)with 1％Fe2O3 equal molar substitution for Al2O3 was soaked in chlorine salt solution for 56 d,the chloride ion binding amount reached 172.75 mg/g.Subsequently,the surface of CAF1 ceramic sand was coated with cement slurry containing 1％NS to form double shell ceramic sand,which was incorporated into unwashed sea sand mortar at 20％,compres-sive strength and impermeability of the mortar are 27.72 MPa and 0.3 MPa at 28 d.Chloride ion was found to be concentrated in the sand with its content deceasing with the distance from the sand,which proves that the chloride ion in the sea sand is bound by the sand in the early stage,and stably fixed in the sand later.
Keywords：sea sand mortarchloride ion bonded ceramic sandfiringchloride ion binding stability
Publication Date：2024-10-25
Online Publishing Date：2025-08-15(First online date of this platform, not the publication date of the document)
Pages：8( 1-7,13 )