轻骨料混凝土渗透性研究

Study on permeability of lightweight aggregate concrete

混凝土的渗透性是耐久性的一个很重要的方面。通过对不同配合比的轻骨料混凝土水渗透试验,研究了轻骨料混凝土的水灰比、抗压强度、含气量和轻骨料的预湿时间对轻骨料混凝土渗透性的影响。试验结果表明:①轻骨料混凝土水灰比越小或抗压强度越高,其渗透系数就越小,抗渗性也就越好;②含气量小的轻骨料混凝土抗渗性优于含气量大的,但是当水灰比较小时,含气量对渗透系数的影响将减弱;③骨料预湿存在最佳预湿时间。轻骨料混凝土并非骨料预湿时间越长,抗渗性越好。

Concrete permeability is an important aspect of concrete durability.Through experiments of water permeability of lightweight aggregate concrete （LWAC） with different mix proportion, the effects of water to cement ratio （W/C）, compressive strength, air content and aggregate pre-wetting time on the LWAC permeability were studied.The experimental results show that ①lower W/C or higher compressive strength of LWAC contributed to smaller permeability coefficient of the LWAC ;② impermeability of LWAC with low air content was better than that of LWAC with high air content.But for LWACs with the lower W/C, the effect of air content on LWAC permeability coefficient will be reduced;and ③ for LWAC permeability, there is an optimum aggregate pre-wetting time, and longer aggregate pre-wetting time can not lead to a better anti-permeation ability of the resulting LWAC.