Based on the hydration characteristics of cement-based materials and the fractal theory of pore structure,the influence of low temperature conditions on the microstructure and macroscopic mechanical properties of cement slurry was studied.The evolution of pore structure of cement-based materials at 0 ℃ and its correlation with the macroscopic proper-ties were mainly studied.The results show that low temperature can significantly inhibit the hydration of cement slurry at early age.Compared with the control group,the hydration inhibition degree of water-cement ratio samples for 12 h,48 h and 96 h is between 59.96％～69.07％,23.86％～38.09％and 3.09％～7.40％,respectively.The compressive strength of the low temperature curing cement slurry is lower than that of the standard curing sample of the same age,and the threshold pore size,the maximum pore size and the porosity are larger.The quantitative analysis of fractal dimension shows that the pore structure of early cement slurry under low temperature has obvious fractal characteristics in gel pore area,capillary pore area and macroscopic pore area,with fractal dimension ranging from 2.000 to 2.789 6.The fractal di-mensions of region Ⅰ,region Ⅱ and region Ⅴ have obvious linear relationship with compressive strength and are inde-pendent of water-cement ratio,which reveals the evolution law of pore structure of cement slurry at 0 ℃.
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