当前位置: X-MOL 学术Cem. Concr. Res. › 论文详情
Our official English website, www.x-mol.net, welcomes your feedback! (Note: you will need to create a separate account there.)
Repair of ordinary Portland cement concrete using ambient-cured alkali-activated concrete: Interfacial behavior
Cement and Concrete Research ( IF 11.4 ) Pub Date : 2020-03-01 , DOI: 10.1016/j.cemconres.2019.105968
Eslam Gomaa , Ahmed Gheni , Mohamed A. ElGawady

Abstract In this paper, alkali-activated concrete (AAC) mixtures synthesized using five different class C fly ashes (FAs) were used as a repair material for structures constructed using conventional Portland cement concrete (CC). The bond strength between ambient-cured AAC and CC was evaluated using slant shear and pull-off tests. Three inclination angles of 45°, 33.75°, and 22.5° were examined during the slant shear test. For the pull-off test, no surface treatment, bonding adhesive treatment, or sandblasting surface treatment were applied to the CC substrate before applying the ACC repair. Full-height cylinders and full-depth beams were also tested as references for comparison purposes. Repairing CC using AAC yielded results similar to those of repairing CC with CC. Using the slant shear test at different angles, the average adhesion between the CC and AAC was found to be 5.8 MPa with a slight increase when increasing the calcium content in the precursor. The average coefficient of friction of the repaired specimens was approximately 0.64. The pull-off test results were sensitive to the surface treatment with sandblasting, which yielded the highest direct tensile strength. The direct and indirect tensile strengths were also analytically correlated to the adhesion from the slant shear test. The SEM results displayed new products such as calcium aluminate silicate hydrate (CASH) at the interface surface, and no sign of visible gap between the substrate and repair materials: i.e., CC and AAC, was observed.

中文翻译:

使用常温固化碱活化混凝土修复普通硅酸盐水泥混凝土:界面行为

摘要 在本文中,使用五种不同的 C 类粉煤灰 (FA) 合成的碱活化混凝土 (AAC) 混合物用作使用常规波特兰水泥混凝土 (CC) 建造的结构的修复材料。环境固化的 AAC 和 CC 之间的粘合强度使用斜剪和拉断测试进行评估。在倾斜剪切试验期间检查了 45°、33.75° 和 22.5° 的三个倾角。对于拉拔测试,在应用 ACC 修复之前,没有对 CC 基材进行表面处理、粘合处理或喷砂表面处理。还测试了全高圆柱体和全深梁作为参考以进行比较。使用 AAC 修复 CC 产生的结果类似于使用 CC 修复 CC 的结果。使用不同角度的斜剪试验,发现 CC 和 AAC 之间的平均附着力为 5.8 MPa,随着前体中钙含量的增加而略有增加。修复后的试样的平均摩擦系数约为 0.64。拉拔测试结果对喷砂表面处理敏感,喷砂处理产生最高的直接拉伸强度。直接和间接拉伸强度也与来自斜切试验的粘附力在分析上相关。SEM 结果显示界面表面有新产物,例如水合铝酸钙(CASH),并且没有观察到基材和修复材料(即 CC 和 AAC)之间的可见间隙迹象。修复后的试样的平均摩擦系数约为 0.64。拉拔测试结果对喷砂表面处理敏感,喷砂处理产生最高的直接拉伸强度。直接和间接拉伸强度也与来自斜切试验的粘附力在分析上相关。SEM 结果显示界面表面有新产物,例如水合铝酸钙(CASH),并且没有观察到基材和修复材料(即 CC 和 AAC)之间的可见间隙迹象。修复后的试样的平均摩擦系数约为 0.64。拉拔测试结果对喷砂表面处理敏感,喷砂处理产生最高的直接拉伸强度。直接和间接拉伸强度也与斜切试验的粘附力在分析上相关。SEM 结果显示界面表面有新产物,例如水合铝酸钙(CASH),并且没有观察到基材和修复材料(即 CC 和 AAC)之间的可见间隙迹象。
更新日期:2020-03-01
down
wechat
bug