粉煤灰综合利用 FLYASHCOMPREHENSIVEUTILIZATION 2017 NO.3 试验与应用 粉煤灰再生混凝土氯离子渗透性能影响因素研究 Study on Influencing Factors of Chloride Ion Permeability of Fly Ash Recycled Concrete 杨益,宁翠萍,苟胜荣,徐志彪 (杨凌职业技术学院建筑工程分院,陕西杨凌712100) 摘要:通过对再生混凝土试件进行氯离子自然扩散试验,研究了粉煤灰掺量、干湿循环、侵蚀时间、孔隙率4 个因素对再生混凝土氯离子渗透性能的影响。
试验研究说明:外掺粉煤灰能够有效提高再生混凝土氯离子渗透性能, 氯离子渗透能力随着粉煤灰掺量增加呈现先增强后减弱趋势,粉煤灰的最优掺量为20%;干湿循环条件可以显著加速 氯离子的渗透性,干湿循环作用对氯离子渗透性的影响与是否掺加粉煤灰关系不大;氯离子扩散速率伴随着侵蚀时间 的延长而明显增大,表层比内部扩散较快,侵蚀前60d扩散较慢,随后加快;氯离子渗透性能随着孔隙率变大而增强, 粉煤灰掺量为20%时孔隙率最低,抗渗性最好。
关键词:粉煤灰;再生混凝土;氯离子;渗透性能;影响因素;干湿循环;孔隙率 中图分类号:TU528.33文献标识码:A文章编号:1005-8249(2017)03-0019-04 Yang Yi, Ning Cuiping, Gou Shengrong, Xu Zhibiao ( Yangling Vocational and Technical College, Yangling,Shanxi, 712100, China ) Abstract: The ffets of fly sh content,wet and dry cycleerosion time and porsityn the chloride n permeability of recycled conret were stbsng ehrid pntans ifsitst reyld etpeimherss shthat thadiinfas n effetively mprove the hloride ion pemeability of recycled cnerete, and the hlride ion pemestion apaity inreses with the inerease f fy ash content, andthen decreases with the ncrease of flyash conten. The optimm content ofly ash is 20% ;The we and dry cyele conditios can significantly accelerate the permeability f chloride ions. The effet of wet and dry cyele on chloride ion permeability is not related to the addition of fy ah. The diffsion rate of chloride ion is bviously icreas with the prolongation of erosion time The surface Gifusion is faster than th intemal difsi, ndthe difusion of the chloride n permebilty ineases with the porsit ncreasing, and the porosity is the lwest whe th fly ash content is 20% and the impermeabilityis the best. Keywords: fly ash; reeycled conerete; hloride ion; permeability; infueneing factors; wet and dry cyele; porosity 混再生混凝土(Recycled AgregateConcrete,简损失。
囚此需要对氯离子侵蚀环境下混凝土结构的渗 称RAC)是将建筑垃圾中的砂石骨料和废弃混凝土透性能进行研究。
目前,围绕普通混凝土抗渗性能的 收集起来,按照一定比例和级配与天然骨料、水泥、国内外研究数量较多,然而对再生混凝土这种新型材 水混合而成,用于工程建设具有巨大的经济效益和环 料的氯离子渗透性能研究不多。
EvangelistalL(等研 保效益。
氯离子所引起的钢筋...