再生骨料混凝土毛细管负压和界面过渡区研究  

Study on Capillary Negative Pressure and Interfacial Transition Zone of Regenerated Aggregate Concrete

作　　者：李晓光[1] 王攀奇 张郁 郭志忠 曹永杰 LI Xiaoguang;WANG Panqi;ZHANG Yu;GUO Zhizhong;CAO Yongjie(School of Civil Engineering,Chang′an University,Xi′an 710061,China;Shaanxi Jianxin Environmental Protection Technology Development Co.,Ltd.,Xi′an 710086,China)

机构地区：[1]长安大学建筑工程学院,陕西西安710061 [2]陕西建新环保科技发展有限公司,陕西西安710086

出　　处：《建筑材料学报》2022年第6期572-576,共5页Journal of Building Materials

基　　金：陕西省科技计划项目重点研发计划项目(2020SF‑360);西安市科技计划项目(2020KJRC0131);西安市科技计划项目(2019210414SYS009CG031)。

摘　　要：研究了再生骨料对混凝土毛细管负压力和界面过渡区(ITZ)性能的影响,分析了不同再生骨料对混凝土早期开裂风险和界面微观形貌的影响.结果表明:天然石子混凝土(NSC)和再生砂浆骨料混凝土(RMC)的毛细管负压力曲线相似,骨料在水泥水化过程中无明显吸释水;与干燥再生砖块骨料混凝土(D-RBC)相比,饱水再生砖块骨料混凝土(S-RBC)的毛细管负压增大,毛细管负压力变化平缓,水泥水化充分,开裂时间推迟;D-RBC的ITZ硬度和弹性模量比S-RBC略有下降,在实际配制再生砖块骨料混凝土时,可对砖块进行饱水处理,其早期开裂风险最低,且力学性能降低不明显.The effects of recycled aggregates on the properties of capillary negative pressure and interfacial transition zone(ITZ)of concrete were studied,and the effects of different recycled aggregates on the early cracking risk and interfacial micro-morphology of concrete were analyzed.The results show that the capillary negative pressure curves of natural stone concrete(NSC)and recycled mortar aggregate concrete(RMC)are similar,and the aggregates have no obvious water absorption and release in the process of cement hydration.Compared with dry recycled brick aggregate concrete(D-RBC),the capillary negative pressure of water saturated recycled brick aggregate concrete(S-RBC)increases.The change of capillary negative pressure of S-RBC is gentle,the cement hydration is sufficient,and the cracking time is delayed.The ITZ hardness and elastic modulus of D-RBC are slightly lower than that of S-RBC.In the actual preparation of recycled brick aggregate concrete,the bricks can be saturated with water,the risk of early cracking is the lowest,and the reduction of mechanical properties is not obvious.

关 键 词：再生骨料 平衡含水率 毛细管负压 纳米压痕 界面过渡区 

分 类 号：TU528.44[建筑科学—建筑技术科学]