García Ramiro, Reyes Encarnación, Villanueva Paula, de la Rubia Miguel Ángel, Fernández Jaime, Moragues Amparo
Department of Civil Engineering, Construction, School of Civil Engineering, Universidad Politécnica de Madrid, 28040 Madrid, Spain.
Department of Mechanical Engineering, Chemistry and Industrial Design Department, E.T.S.I.D.I, Universidad Politécnica de Madrid, 28040 Madrid, Spain
Materials (Basel). 2020 Mar 5;13(5):1169. doi: 10.3390/ma13051169.
The addition of a range of micro- and nano-particles to high-performance concrete has been the focus of recent research. At present, studies are mainly aimed at designing customised mortars, providing them with specific properties for each application. Improving the durability of mortars is one of the main objectives in such research, as a result of increasing environmental concern. The research presented herein analyses the synergistic effect of nanosilica and metakaolin as additives on the service life of cement-based mortars subject to aggressive environments (i.e., chloride exposure) at early ages. The effects of the additives on the durability properties of submerged samples after two and three days of curing were analysed. Tests were conducted on several different properties: resistivity, porosity, mechanical properties, chloride diffusion, and service life. It is observed that metakaolin and nanosilica exhibit a synergistic effect as additives, which is related to porosity refinement and chloride ion binding capacity, which contributes to enhanced resistance against chloride penetration from very early ages.
在高性能混凝土中添加一系列微米和纳米颗粒一直是近期研究的重点。目前，研究主要致力于设计定制化的砂浆，使其具备适用于每种应用的特定性能。由于对环境的关注度不断提高，提高砂浆的耐久性是此类研究的主要目标之一。本文所呈现的研究分析了纳米二氧化硅和偏高岭土作为添加剂对处于侵蚀性环境（即氯化物暴露）中的水泥基砂浆早期使用寿命的协同作用。分析了添加剂对养护两天和三天后浸没样品耐久性的影响。针对几种不同性能进行了测试：电阻率、孔隙率、力学性能、氯化物扩散和使用寿命。可以观察到，偏高岭土和纳米二氧化硅作为添加剂表现出协同作用，这与孔隙细化和氯离子结合能力有关，有助于从很早的龄期就增强对氯离子渗透的抵抗能力。
