SENSOR-INFRA: Smart Engineered Cementitious Composites for Intelligent Infrastructure

目前的全球基础设施老化和恶化，维持其功能所需的投资规模巨大。随着许多国家进入紧缩和财政紧缩的时代，对基础设施寿命延长的需求目前比以往任何时候都更加普遍。然而，在这些国家，由于缺乏关于资产真实“健康状态”的可靠数据，资产所有者很难管理其基础设施。拟议的研究中心是开发具有内置自监测系统的工程水泥复合材料，称为智能ECC（s-ECC）。这种自我监测功能可以为未来的土木工程基础设施提供“大脑和神经”系统，使结构能够感知和响应内部变化和外部环境，而无需额外的传感器。此外，将“智能”引入ECC还可以使材料具有许多非结构应用，从而使材料具有多功能性。s-ECC的电性能。这将是第一个对ECC的电气性能进行详细研究的项目，从初始测量，到整个设置和长期硬化，再到机械和环境负载下的压阻响应。对这些技术方面的更全面的理解将允许开发标准化的测试协议，这些协议可以在现实世界的应用中进一步实施。该研究的新奇在于使用回收的研磨碳（MC）纤维作为ECC系统中的导电填料。由于MC纤维的长度等于ECC的特征裂纹宽度，因此预计纤维将不会桥接ECC中的微裂纹，从而允许保持材料对裂纹形成的敏感性，从而实现其作为损伤传感器的功能。同时，MC纤维的高纵横比将允许在实际低剂量率下在ECC基质内形成电连续性。这是“分散的”纤维网络是必不可少的，以确保材料中的水合作用和水分变化的影响不会对体积电导率产生明显影响，从而最大限度地减少错误感测。

Current global infrastructure is plagued by ageing and deterioration and the scale of investment needed for maintaining its functionality is immense. With many nations having entered an era of austerity and financial restraint, the demand for infrastructure life-extension is currently more prevalent than ever. In these countries, however, asset owners have difficulties managing their infrastructure due to the absence of reliable data about the true 'state of health' of their assets.The proposed research centres on the development of engineered cementitious composites with a built-in self-monitoring system termed smart-ECCs (s-ECCs). This self-monitoring feature can provide future civil engineering infrastructure with a 'brain and nervous' system, enabling structures to sense and respond to the internal changes and external environment without the need of additional sensors. Furthermore, introducing 'smartness' to ECCs could also give the material a number of non-structural applications thereby making the material multi-functional.The research proposed will provide a comprehensive study of the rheological, mechanical and a.c. electrical properties of s-ECCs. It will be the first to undertake a detailed study into the electrical properties of ECCs from initial gauging, throughout setting and long-term hardening and into its piezo-resistive response under mechanical and environmental loading. A fuller understanding of these technical aspects will allow development standarised test protocols that can be further implemented in real-world applications. The novelty of the proposed research lies in the use of recycled, milled carbon (MC) fibres as conductive filler in ECC systems. As the length of MC fibres is equivalent to the characteristic crack width of ECCs, it is anticipated that the fibres will not bridge the micro-cracks in ECC, allowing the material sensitivity to cracks formation to be maintained thereby fulfilling its function as a damage sensor. At the same time, the high aspect ratio of MC fibres would allow the formation electrical continuity within the ECC matrix at practically low dosage rates. This is 'percolated' fibre network is essential to ensure that the influence of hydration and moisture changes in the material will not have appreciable influence on the bulk conductivity thereby minimising false sensing.