摘要
针对再生骨料透水混凝土在不同介质冻融循环下的性能变化进行了系统研究,通过制备不同配合比的再生骨料透水混凝土试件,并在水、盐水和去离子水等不同介质中进行冻融循环实验,探究冻融循环对混凝土质量损失率、相对动弹性模量、抗压强度剩余量、连续孔隙率和透水系数的影响。结果表明,120次冻融后,2组试样质量损伤率均接近最大值;盐水环境下抗压强度损失更快,60次后强度降低至75%;盐水组连续孔隙率和透水性更高,70次后孔隙率达27.1%,透水系数达4.4%。扫描电镜和XRD分析显示,盐冻初期化学侵蚀显著,产生膨胀物充填微裂隙,后期物理侵蚀加剧冻融损伤,表现为透水率快速上升后缓慢增加,强度逐渐下降,为优化其抗冻性能提供了实验参考。
The properties of recycled aggregate permeable concrete under different media freeze-thaw cycles were systematically studied.By preparing different proportions of recycled aggregate permeable concrete specimens and performing freeze-thaw cycling experiments in different media such as water,brine and deionized water,the effects of freeze-thaw cycling on the mass loss rate,relative dynamic elastic modulus,residual compressive strength,continuous porosity and permeability coefficient of concrete were investigated.The results showed that after 120 freeze-thaw cycles,the quality damage rate of the two groups of specimens was close to the maximum value.In the saline environment,the compressive strength loss was faster,and the strength decreased to 75%after 60 cycles.The continuous porosity and water permeability of the saline group were higher,with a porosity of 27.1%and a permeability coefficient of 4.4%after 70 cycles.Scanning electron microscopy and XRD analysis showed that the chemical erosion was significant in the early stage of salt freezing,and the expansion material filled the micro-cracks.The physical erosion worsened the freeze-thaw damage in the later stage,which showed that the water permeability increased rapidly and then increased slowly,and the strength gradually decreased,which provided an experimental reference for optimizing the anti-freezing performance of salt.
作者
黎雨佳
李少璇
夏磊华
Li Yujia;Li Shaoxuan;Xia Leihua(Macao University of Science and Technology,Dangzai 999078,China;Neusoft Institute Guangdong,Foshan 528000,China)
出处
《能源与环保》
2024年第11期151-158,共8页
CHINA ENERGY AND ENVIRONMENTAL PROTECTION
关键词
再生骨料
透水混凝土
冻融循环
微观损伤
recycled aggregate
permeable concrete
freeze-thaw cycle
microscopic damage
作者简介
黎雨佳(1993-),女,广东佛山人,博士研究生,研究方向为建筑修复与再利用。
