摘  要：基于低場核磁共振技術，研究了聚丙烯纖維摻量分別為0、0.6 kg/m3、0.9 kg/m³和1.2 kg/m³以及粗骨料取代率為40%的煤矸石混凝土在凍融作用下T2譜面積的分布與變化特征、內部微觀孔結構分布特性以及孔隙凍融損傷規律。結果表明，隨著凍融循環次數的增加，T2譜整體呈右移趨勢，即向大孔隙方向偏移，且T2譜面積逐漸增大的同時第一峰面積所占百分比在減小，第二峰和第三峰面積所占百分比在增加，表明凍融循環使煤矸石混凝土內部的大孔隙大幅增加，內部出現了明顯的凍融損傷；0.6 kg/m³的聚丙烯纖維對煤矸石混凝土內部孔隙的細化作用最好。

Abstract: Based on low-field nuclear magnetic resonance(NMR), the T2 spectrum distribution, T2 spectrum area variation, internal micro-pore structure distribution and pore freeze-thaw damage law of coal gangue concrete with 40% replacement rate of coarse aggregate and with 0, 0.6 kg/m³, 0.9 kg/m³ and 1.2 kg/m³ polypropylene fibre content under freeze-thaw cycles were studied. The results show that with the increase of freeze-thaw cycles, the whole T2 spectrum shifts to the right direction, that is to the direction of macro-pore, and with the area of T2 spectrum increases gradually, the percentage of the first peak area decreases, while the percentages of the second and third peak area increase, which indicates that the freeze-thaw cycle greatly increases the macro-pore in coal gangue concrete and causes obvious freeze-thaw damage. When the content of polypropylene fibre is 0.6 kg/m³, the fining effect on the internal pore of gangue concrete is the best.