不同沥青体分比环氧树脂沥青混合料的断裂性能研究

固化的环氧树脂沥青由树脂相与沥青相构成。该文介绍了其沥青混合料的断裂性能的试验研究。随着沥青用量的增加,则环氧树脂沥青基体逐渐从树脂相过渡到沥青相,相应其性能会发生很大变化。采用旋转压实成型半圆形试件,通过对0.250、0.400、0.500和0.571四种不同沥青体分比的环氧树脂沥青及AH-70普通沥青、SBS改性沥青混合料,进行-25℃、-15℃、-5℃和5℃四个温度下的三点弯曲对比试验研究,并通过扫描电镜(SEM)进行微观结构形态分析。研究表明,沥青体分比低于0.400时,环氧树脂沥青混合料的最大荷载、断裂能、断裂韧度与锯缝深度、与温度的关系的变化趋势均表现出与AH-70普通沥青及SBS改性沥青混合料较大差异,沥青体分比高于0.400,则环氧树脂沥青混合料的断裂性能变化趋势与AH-70普通沥青及SBS改性沥青混合料相似。SEM微观结构研究表明,沥青体分比为0.400时,环氧树脂沥青是以树脂相为基体,沥青为近似球形分散体,沥青体分比为0.500时,沥青相为基体,树脂为近似球形(胶团)分散体。沥青体分比为0.400到0.500为环氧树脂沥青的相逆转区间。

Study on Fracture Performance of Epoxy Resin Asphalt Mixture with Different Asphalt Fractions

The cured epoxy resin asphalt is composed of resin phase and asphalt phase.The article introduces the testing study of fracture performance of asphalt mixture.With the increase of asphalt dosage,the matrix of epoxy resin asphalt changes from resin phase to asphalt phase and its corresponding performance will greatly change.Four different asphalt fractions 0.250,0.40,0.500 and 0.571 of epoxy resin asphalt,AH-70 conventional asphalt and SBS modified asphalt mixtures are studied of three-point bending contrast tests under four temperatures of-25℃,-15℃,-5℃ and 5℃ by using the rotary compacting semi-circular specimen,and are carried out of the micro-structure shape analysis by scanning electron microscope(SEM).The study shows that the variation trends of the maximum load,fracture property and fracture toughness of epoxy resin asphalt mixture related to the cutting depth and temperature are greatly different from AH-70 ordinary asphalt and SBS modified asphalt mixtures when the asphalt fraction is lower than 0.400,and the variation trend of fracture property of epoxy resin asphalt mixture is similar with AH-70 ordinary asphalt and SBS modified asphalt mixtures when the asphalt fraction is higher than 0.400.The SEM micro-structure study shows that that epoxy resin asphalt is the matrix of resin phase and the asphalt is the approximate spherical dispersion when asphalt faction is 0.400,and the asphalt phase is the matrix and the resin is the approximate spherical(micelle) dispersion when the asphalt faction is 0.500.The asphalt faction from 0.400 to 0.500 is the phase reversal interval of epoxy resin asphalt.