氯离子渗透对混凝土表层渗水系数及微观结构的影响

发布时间：2018-06-20 11:02

本文选题：表层渗水系数 + 孔结构　；参考：《功能材料》2014年11期

【摘要】：使用不同配合比的混凝土试件及颗粒标准养护28 d后,浸泡在超纯水和5%的NaCl溶液中,采用表面渗透性测试仪(Autoclam)和氮气吸附法定期检测混凝土的表层渗水系数及微观孔结构,研究氯离子对混凝土表层渗水性能及水泥水化浆体微观结构的影响。结果表明,NaCl溶液浸泡会显著提高混凝土表层的抗渗能力,对PC1混凝土,浸泡90 d后,表层渗水系数为超纯水浸泡试件的0.91,150 d后仅为超纯水试件的0.76;氯离子浸入混凝土后,会使混凝土的孔结构细化,显著降低100 nm以下的小孔,实验中,PC1混凝土在NaCl溶液浸泡后,小于100 nm的孔与超纯水浸泡相比减少了32.43%;PC2混凝土在NaCl溶液浸泡后,小于100 nm的孔相比减少了57.24%;NaCl溶液浸泡下,水泥水化良好,结构较致密,氯离子对水泥浆体的水化过程有一定的促进作用。
[Abstract]:After 28 days of standard curing of concrete specimens and particles with different mix ratios, the concrete samples were immersed in ultra-pure water and 5% NaCl solution. The surface permeability test instrument Autoclamp) and nitrogen adsorption method were used to regularly detect the surface water permeability coefficient and microstructure of concrete. The effect of chloride ion on the surface water permeability of concrete and the microstructure of cement hydrated slurry was studied. The results show that the impermeability of concrete surface layer can be improved significantly by soaking in NaCl solution. For PC1 concrete, after 90 days of immersion, the surface water permeability coefficient of PC1 concrete is only 0.76 of that of ultra-pure water sample after 0.91150 days of soaking in ultra-pure water, and that of concrete immersed in chloride ion is only 0.76. The pore structure of concrete will be refined, and the pore size below 100 nm will be significantly reduced. In the experiment, after immersion in NaCl solution, the pore less than 100 nm will reduce 32.43% PC2 concrete after immersion in NaCl solution, compared with ultra-pure water immersion. When the pore size less than 100 nm is reduced by 57.24% NaCl solution, the hydration of cement is good and the structure is compact. Chloride ions can promote the hydration process of cement paste to some extent.
【作者单位】：深圳大学土木工程学院广东省滨海土木工程耐久性重点实验室;
【基金】：国家自然科学基金青年基金资助项目(51108271) 国家重点基础研究发展计划(973计划)资助项目(2011CB013604) 深圳市科技计划资助项目(JCYJ20120613115622154)
【分类号】：TU528

【共引文献】