您的位置：首页 > 论文页面
混合料贮存期对预拌补偿收缩混凝土微观结构影响试验分析
发表时间：2016-10-31 浏览量：1819 下载量：420
| 全部作者： | 马芹永，张阳阳 |
| 作者单位： | 安徽理工大学土木建筑学院；安徽理工大学矿山地下工程教育部工程研究中心 |
| 摘 要： | 为研究干拌混合料贮存期对预拌补偿收缩混凝土微观结构的影响，当膨胀剂掺量为6%、砂子含水率为1.0%时，对6种贮存期（3，7，10，15，20，30 d）的预拌补偿收缩混凝土进行微观结构试验。结果表明，当干拌混合料贮存期为3，7，10 d时，混凝土中存在大量C-S-H凝胶和针棒状AFt晶体，密实性较好，随着贮存期的增加，水泥石结构中孔洞直径分别为3.075，3.979，5.885 μm，微裂缝宽度分别为0.364，0.450，0.703 μm，界面过渡区（intertacial transition zone，ITZ）中的粘结裂缝宽度分别为0.554，0.949，1.280 μm. 当贮存期为15，20，30 d时，水泥石结构中孔洞直径分别为6.137，6.335，7.033 μm，微裂缝宽度分别为1.230，1.352，1.370 μm，变化幅度较大，取向排列的Ca(OH)2晶体增多，C-S-H凝胶数量相对减少，混凝土密实度下降，其附近结构中有新微裂缝存在，且微裂缝尺寸随贮存期的增加而不断增大。 |
| 关 键 词： | 地下工程；补偿收缩混凝土；干拌混合料；贮存期；微观结构；界面过渡区 |
| Title： | Effects of storage periods for dry-mixed materials on microstructure of ready-mixed shrinkage-compensating concrete |
| Author： | MA Qinyong, ZHANG Yangyang |
| Organization： | School of Civil Engineering and Architecture, Anhui University of Science and Technology; Engineering Research Center of Underground Mine Construction, Ministry of Education, Anhui University of Science and Technology |
| Abstract： | In order to study the effect of the storage period for dry-mixed materials on the microstructure of the ready-mixed shrinkage-compensating concrete, microstructure test is carried out with respect to six different kinds of storage periods (3, 7, 10, 15, 20, 30 d), and with the constant expansive agent dosage of 6% and sand moisture content of 1.0%. The results show that when the storage periods of the dry-mixed materials are 3, 7, 10 d, respectively, there exist mass of C-S-H gel and AFt crystal. With the increasing storage period, the diameters of holes are 3.075, 3.979, 5.885 μm, the breadths of micro cracks are 0.364, 0.450, 0.703 μm, and the breadths of micro cracks in the intertacial transition zone (ITZ) are 0.554, 0.949, 1.280 μm. When the storage periods of the dry-mixed materials are 15, 20, 30 d, the diameters of holes are 6.137, 6.335, 7.033 μm, respectively, the breadths of micro cracks are 1.230, 1.352, 1.370 μm, and the increase amplitude is big. The Ca(OH)2 crystals in the oriented arrangement increase, while the C-S-H gel quantity decreases gradually. The intensity of concrete shows a decreasing trend, while there exist new micro cracks nearby the transition zone of the interface, and the size of the micro cracks increases gradually with the increasing storage period. |
| Key words： | underground engineering; shrinkage-compensating concrete; dry-mixed material; storage periods; microstructure; interfacial transition zone |
| 发表期数： | 2016年10月第20期 |
| 引用格式： | 马芹永，张阳阳. 混合料贮存期对预拌补偿收缩混凝土微观结构影响试验分析[J]. 中国科技论文在线精品论文，2016，9（20）：2125-2132. |
2
评论数 0请您登录
暂无评论
下载全文
多维论文