氯盐侵蚀对再生混凝土多重界面显微结构的影响

通过研究经氯盐侵蚀的再生混凝土不同界面的显微硬度变化,确定不同强度等级再生混凝土不同界面过渡区的范围,研究氯盐侵蚀期对再生混凝土不同界面显微结构的影响规律,揭示了再生混凝土多重界面氯盐侵蚀的劣化机理。研究表明：随着氯盐侵蚀龄期的增长,同强度再生混凝土LG-XJ界面、LJ-XJ界面和LG-LJ界面的显微硬度逐渐降低,过渡区范围逐渐增加。侵蚀龄期为30 d时,C30再生混凝土的LJ-XJ界面过渡区范围几乎无变化；侵蚀龄期为90 d时,C60再生混凝土的LJ-XJ界面过渡区范围变化仍不明显。同强度再生混凝土界面抗氯盐侵蚀性能强弱关系：LJ-XJ界面抗氯盐侵蚀性能>LG-LJ界面抗氯盐侵蚀性能>LG-XJ界面抗氯盐侵蚀性性能。不同氯盐侵蚀龄期的再生混凝土,随着强度等级的提高,LG-XJ界面、LJ-XJ界面和LG-LJ界面的显微硬度与过渡区范围以及水泥浆体本身的显微硬度改变的幅度都有不同程度的降低。

Effect of Chlorine Salt Erosion on Multiple Interface Microstructure of Recycled Concrete

Through the study of recycled concrete by the chlorine salt erosion the micro-hardness of different interface changes, determine different recycled concrete strength grade and different interface transition zone, the chlorine salt erosion period the influence law of different interface microstructure of recycled concrete, reveals that the recycled concrete multiple interface degradation mechanism of the chlorine salt erosion. The study shows that: as the growth of the chlorine salt erosion age, with the strength of recycled concrete LG-XJ interface, LJ-XJ and LG-LJ interface of micro-hardness gradually reduce, transitional zone increased gradually. Erosion age of 30 d, C30 recycled concrete LJ-XJ interface transition zone range is almost have no change; Erosion age for 90 d, recycled concrete C60 LJ-XJ interface transition zone range change is not obvious. With the chlorine salt erosion resistance strength of recycled concrete interface strength relationships: LJ-XJ interface the chlorine salt erosion resistance >LG-LJ interface the chlorine salt erosion resistance>LG-XJ interface the chlorine salt erosion resistance performance. Different ages of the chlorine salt erosion of recycled concrete, with the improvement of strength grade, LG-XJ interface, LJ-XJ and LG-LJ interface of micro-hardness and transition zone and micro-hardness change of cement paste itself have different degree of reduction in amplitude.