养护条件对混凝土气泡特征参数的影响

Influence of curing conditions on bubble characteristic parameters of concrete

针对硬化混凝土内部气孔较多导致工程质量及耐久性较差的问题,采用单一变量原则制备了两组蒸汽养护和标准养护条件下的混凝土,试验利用混凝土气孔结构分析仪对两组混凝土不同位置的含气量、气泡间距系数、气泡比表面积等重要参数进行研究。试验结果表明:混凝土中气泡在沿高度范围稳定性较差,养护方式对混凝土不同位置的气泡有不同的影响规律;硬化初期蒸汽养护能够改善混凝土内部气泡结构,细化气泡,但对表面气泡存在负面影响,使表面气泡比表面积变小。

Aiming at the problem of poor engineering quality and durability caused by many air holes in hardened concrete,two groups of concrete under steam curing and standard curing conditions are prepared by using the single variable principle.The important parameters such as air content,bubble spacing coefficient and bubble specific surface area at different positions of the two groups concrete are studied by using concrete pore structure analyzer.The results show that the stability of bubbles in concrete along the height range is poor,and the curing methods have different effects on bubbles in different positions of concrete.Steam curing at the initial stage of hardening can improve the internal bubble structure of concrete and refine bubbles,but it has a negative impact on surface bubbles and reduce the specific surface area of surface bubbles.