The temperature transfer rule in the ordinary concrete and porous concrete pavement under low temperature condition have been analyzed by means of numerical analysis, the temperature transfer and the distribution of temperature field in porous concrete pavement under the winter freeze-thaw cycles action have been simulated. The temperature transfer analytic equations of the porous concrete have been established based on the analysis of composite way of the heat transfer convection-conduction inside the porous concrete. The distribution rule of temperature field in porous concrete pavement is analyzed, simulating the porous concrete pavement of WULUMUQI airport under low temperature in coldest month. The analysis result indicates that the bagger of the connected pore, or the smaller for the spans from pores in the porous concrete, the faster of the temperature transmission speed, and more quicker of the speed of freezing. Freeze -thaw and compressive experiments have been conducted using the tetrahedron particles mode to simulate the internal porous concrete, and the freezing-thawing resistance rules of contacted particles in the tetrahedron have been tested. Testing results shows that the contacted strength of the particles decreases with the increases of freeze-thaw cycles, and the reduction of the strength is significantly in the initial 30 cycles, and the strength would been reduced nearly half after 50 cycles.%利用数值分析的方法,分析了普通混凝土道面和多孔混凝土道面在低温环境下温度传递的规律,并对多孔混凝土道面表层结构在冬季冻融循环作用下的温度传递过程与温度场分布进行了数值模拟.基于多孔混凝土道面温度内部热传递对流-传导复合方式的分析,建立了多孔混凝土内部温度传递解析方程.以乌鲁木齐机场道面冬期低温月份的表层结构温度场变化规律为例,分析在采用多孔混凝土时的内部温度场分布规律.分析结果表明,多孔混凝土中对外连接孔直径越大,或孔隙间距越小时,其温度传递速度就越快,混凝土受冻速度也越快.利用四面体堆积结构等效多孔混凝土内部结构的间接方式进行了低温冻融和强度实验,并测试了堆积颗粒间点接触的抗冻性能变化规律.实验结果表明,多孔混凝土中颗粒间点接触强度随冻融次数增多而降低,且在前30次冻融过程中降低更显著,50次冻融循环后的强度降低可达50％.
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