防水剂对受荷开裂下PVA-SHCC渗透性能的影响

发布时间：2018-03-23 06:29

本文选题：PVA-SHCC　切入点：氯离子扩散系数　出处：《混凝土》2014年12期 　论文类型：期刊论文

【摘要】：受荷载时产生的多重裂缝是SHCC的薄弱部位和外界介质侵入的通路,会加速了结构的耐久性劣化。而对SHCC进行防水处理是提高耐久性的有效措施,研究了防水剂对PVA-SHCC试件抗氯离子渗透性能和受荷开裂下的试件水毛细吸收系数的影响。试验结果表明:对PVA-SHCC进行防水处理可以显著降低试件中的氯离子扩散系数,外涂防水剂试件的氯离子扩散系数只是不掺防水剂的试样的8%到20%,内掺防水剂的试件的氯离子扩散系数只是不掺防水剂试件的60%左右。试件在受荷开裂下的抗渗性比未施加应力试件的抗渗性差,采取防水处理可以有效提高受荷试件的抗渗性能,外涂和内掺处理方式对提高抗渗的效果相差不大。SHCC渗透性能的研究可以为SHCC结构耐久性研究和服役寿命预测提供重要参考。
[Abstract]:The multiple cracks caused by loading are the weak part of SHCC and the passage of external media, which will accelerate the deterioration of the durability of the structure. The waterproof treatment of SHCC is an effective measure to improve the durability. The effect of water repellent on the chloride permeation resistance of PVA-SHCC specimens and the absorption coefficient of water capillary under loading cracking was studied. The results showed that the water repellent treatment with PVA-SHCC could significantly reduce the chloride diffusion coefficient in the specimens. The chloride diffusion coefficient of the sample coated with water repellent is only 8% to 20% of that of the sample without water repellent, and the chloride diffusion coefficient of the specimen with water repellent is only about 60% of that of the specimen without water repellent. The impermeability of the specimen under loading cracking is only about 60%. The impermeability of the specimen is worse than that of the specimen without stress. The waterproof treatment can effectively improve the impermeability of loaded specimens. The study on the impermeability of SHCC structure by coating and admixture treatment can provide an important reference for the durability study and service life prediction of SHCC structures.
【作者单位】：青岛理工大学土木工程学院;青岛市高新区工程质量检测有限公司;
【基金】：国家自然科学基金项目(51378269;51378270;51178230)
【分类号】：TU528.042

【共引文献】