摘要
采用外加均匀约束应力的方法,研究了膨胀剂掺量对不同约束条件下混凝土抗压强度、劈裂抗拉强度和弹性模量的影响,并用扫描电镜对混凝土的微观结构进行分析.试验结果表明:膨胀混凝土在不同约束条件下力学性能均有不同程度的提高,其中三向约束条件>双向约束条件>单向约束条件.微观分析表明,膨胀混凝土的微观结构受约束条件的影响较大,并且约束条件越强其微观结构越致密,这是约束条件显著提高膨胀混凝土力学性能的内因所在.
In this paper, the method of applying uniform restraint stress was used to study the effect of the mixing amount of expansive agent on compressive strength, splitting tensile strength and elastic modulus of expansive concrete under different restrained conditions. The microstructure of expansive concrete was analyzed by scanning electron microscopy （SEM）. The test results indicate that the compressive strength, splitting tensile strength and elastic modulus of expansive concrete under different restrained conditions have been improved to some extent,and the mechanical property under three-dimensionally restrained conditions ranks first, the mechanical property under two-dimensionally restrained conditions ranks second, and the mechanical property under one-dimensionally restrained condition ranks third. The analysis of SEM images show that restrained conditions have great impact on microstructure of expansive concrete, and the microstructure of expansive concrete becomes more compact as the restrained conditions become stronger. This is the internal cause for restrained conditions to significantly improve the mechanical properties of expansive concrete.
出处
《天津城建大学学报》
2017年第6期405-410,共6页
Journal of Tianjin Chengjian University
基金
国家十二五科技支撑计划项目(2013BAJ10B03)
关键词
膨胀混凝土
约束条件
强度
弹性模量
微观结构
expansive concrete
restrained conditions
strength
elastic modulus
microstructure
