关键词: 磷酸钾镁水泥;抗冻性;抗盐冻性;硫酸盐侵蚀

Abstract: The mass loss,strength,volume deformation and apparent failure form of magnesium phosphate cement paste in four different freeze-thaw mediums were determined and compared with the magnesium phosphate cement paste in long-term immersion environment of the same age in order to study the potassium magnesium phosphate cement salt-freeze resistance.Moreover,the phase composition and microstructure of hardened magnesium phosphate cement were studied by micro means.The results show that magnesium potassium phosphate cement has better salt frost resistance,as the result of the quality of the magnesium phosphate cement is not more than 5％ after the 400 freeze-thaw cycles,the strength loss is less than 25％,and the volume expansion deformation is 0.275％.The damage was most serious when 5％ sodium sulfate solution was used as the freezing and thawing medium in the four kinds of freeze-thaw media,which can be used as an index to evaluate the performance of potassium magnesium phosphate cement against salt and frost.

Key words: magnesium potassium phosphate cement;frost resistance;salt-freeze resistance;sulfate attack