To address the challenge of appropriate cementitious materials that can support future optical fibre sensors with reduced strains for smart city infrastructure, reducing structural heterogeneity by integrating diatomous earth is proposed. A series of samples made up of commercial grade instant mortar and an increased percentage of diatomous earth are fabricated and characterised. Mindful of the growing importance of “in-the-field” measurements and diagnostics to wider construction technology evolution, hardness properties are measured using Mohs scratch test and portable field durometers; the latter was shown to be effective in post-plasticity assessment of these cement composites. Within experimental error low added concentrations improve cement hardness whilst making the cement more plastic. Structural colour is introduced by the diatoms and novel characterisation using a smartphone and polymer lens proposed and demonstrated. The implications for CO₂ trapping and intelligent structural health monitoring (ISHM) for internet-of-things (IoT) in smart city infrastructure are discussed.

中文翻译：

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用于智能传感器和建筑物的砂浆-硅藻复合材料

为了解决合适的胶结材料的挑战，该材料可以支持未来用于智能城市基础设施的具有减小的应变的光纤传感器，建议通过整合硅藻土来减少结构异质性。制造并表征了一系列由商品级速溶砂浆和增加百分比的硅藻土组成的样品。考虑到“现场”测量和诊断对于更广泛的建筑技术发展的日益重要的意义，使用莫氏刮擦测试和便携式现场硬度计来测量硬度特性；后者被证明对这些水泥复合材料的可塑性评估有效。在实验误差范围内，低添加浓度可提高水泥硬度，同时使水泥更具塑性。硅藻介绍了结构颜色，并提出并演示了使用智能手机和聚合物镜片进行的新颖表征。对一氧化碳的影响₂讨论了智能城市基础设施中物联网（IoT）的陷阱和智能结构健康监控（ISHM）。