纳米工程化混凝土研究新进展

Latest Research Progress on Nano-Engineered Concrete

混凝土是人类文明在地球上有形足迹的最明显表现之一, 其应用量大面广, 已成为世界上用量最大的人造工程材料。相对于其他工程材料, 混凝土的生产资源和能源消耗少、有害副产品少、环境损害小; 同时因其优异的抗压和耐疲劳等力学性能以及耐水和抗火性, 应用混凝土建造的基础设施具有高安全和耐久性以及维护少等优点, 因此混凝土是人类建造工程领域可持续发展的可靠选择且未来仍不可或缺的建筑材料。但混凝土固有缺点和现有性能不能很好满足人类未来生存空间的建造和拓展的要求, 而且大量混凝土的生产和使用对资源、能源和环境影响巨大。纳米科学与技术可从最基础层面理解和调控混凝土, 从而实现混凝土的 (超) 高性能化以及多功能/智能化, 进而为解决上述挑战并实现可持续发展注入动力。本文聚焦纳米工程化混凝土的增强/改性机理、制备与性能调控、性能和功能表征与工程应用三方面相关核心研究进展, 主要介绍包括纳米中心效应 (Nano-core effect) 、纳米中心效应区、纳米中心效应改善界面的迁移富集效应、纳米中心效应诱导的超硬水化硅酸钙凝胶相、纳米级孔结构特征等科学现象解释/原理探究, 纳米工程化混凝土的性能调控与大规模制备的先进技术探索 (如表面处理、自组装、原位生长等) , 以及纳米工程化混凝土性能拓展和土木、交通、市政、海洋、能源、军事等领域工程应用验证等方面获得的认识。

As one of the most obvious manifestations of tangible footprint of human civilization on Earth, concrete is largely and widely applied, and has become the largest amount of man-made engineering material in the world. Compared with other engineering materials, concrete consumes less production resource and energy, has fewer harmful by-products, and causes less environmental impact. Additionally, due to its excellent mechanical properties, such as compressive strength and fatigue resistance, along with its water and fire resistance, the infrastructure constructed by applying concrete has the advantages of high safety, durability, and low maintenance. Consequently, concrete remains a reliable choice for sustainable development of the field of human construction and engineering and remains indispensable in the future. However, inherent shortcomings and current performance limitations of concrete do not meet the requirements for the construction and expansion of human living spaces in the future. Moreover, the production and use of large quantities of concrete have a significant impact on resources, energy, and environment. Nanoscience and nanotechnology can be used to understand and control concrete at its fundamental level, enabling the realization of (ultra) high-performance and multifunctional/smart concrete, which in turn can give impetus to addressing the aforementioned challenges and achieving sustainable development. This article focuses on three core research advancements related to enhancement/modification mechanisms, preparation and performance control, and performance and functionality characterization for engineering applications of nanoengineered concrete. It mainly introduces the explanation/principle investigation of scientific phenomena including nano-core effect, nano-core effect zone, nano-core effect-induced enrichment effect for interface enhancement, nano-core effect-induced ultrahigh-density calcium silicate gel, and nanoscale pore structure characteristics, the exploration of advanced technologies for performance modulation and large-scale preparation of nano-engineered concrete (e. g. , surface treatment, self-assembly, and in-situ growth techniques, etc. ) , as well as the understanding gained from the expansion of the properties of nanoengineered concrete and the validation of engineering applications in the fields of civil engineering, transportation, municipal, marine, energy, and military.