Syamsunur Deprizon, Wei Li, Ahmed Memon Zubair, Surol Salihah, Md Yusoff Nur Izzi
Department of Civil Engineering, Faculty of Engineering, Technology and Built Environment, UCSI University, Kuala Lumpur 56000, Malaysia.
Postgraduate Studies, Universitas Bina Darma Palembang, Kota Palembang 30111, South Sumatera, Indonesia.
Materials (Basel). 2022 Oct 11;15(20):7073. doi: 10.3390/ma15207073.
Fire and extreme heat environmental changes can have an impact on concrete performance, and as climate change increases, new concrete structures are being developed. Nano-silica and nano-calcium carbonate have shown excellent performances in modifying concrete due to their large specific surface areas. This review describes the changes in concrete modified with nano-silica (NS) and nano-calcium carbonate (NC), which accelerate the hydration reaction with the cementitious materials to produce more C-S-H, resulting in a denser microstructure and improved mechanical properties and durability of the concrete. The mechanical property decay and visualization of deformation of mixed NS and NC concrete were tested by exposure to high temperatures to investigate the practical application of mixed composite nanomaterials (NC+NS) to concrete. The nano-modified concrete had better overall properties and was heated at 200 °C, 400 °C, 600 °C and 800 °C to relatively improve the mechanical properties of the nano concrete structures. The review concluded that high temperatures of 800 °C to 1000 °C severely damaged the structure of the concrete, reducing the mechanical properties by around 60%, and the dense nano concrete structures were more susceptible to cracking and damage. The high temperature resistance of NS and NC-modified nano concrete was relatively higher than that of normal concrete, with NC concrete being more resistant to damage at high temperatures than the NS samples.
火灾和酷热等环境变化会对混凝土性能产生影响，随着气候变化加剧，新型混凝土结构不断被研发出来。纳米二氧化硅和纳米碳酸钙因其较大的比表面积，在混凝土改性方面表现出优异性能。本综述描述了用纳米二氧化硅（NS）和纳米碳酸钙（NC）改性的混凝土的变化情况，它们加速了与胶凝材料的水化反应，生成更多的C-S-H，从而使混凝土微观结构更致密，机械性能和耐久性得到改善。通过高温暴露试验，测试了NS和NC混合混凝土的力学性能衰减及变形可视化情况，以研究混合复合纳米材料（NC+NS）在混凝土中的实际应用。对纳米改性混凝土进行200℃、400℃、600℃和800℃加热，以相对改善纳米混凝土结构的力学性能，其整体性能更佳。综述得出结论，800℃至1000℃的高温严重破坏了混凝土结构，使其力学性能降低约60%，致密的纳米混凝土结构更容易开裂和受损。NS和NC改性纳米混凝土的耐高温性能相对高于普通混凝土，其中NC混凝土在高温下比NS样品更耐损伤。
