Accelerating ultra low-carbon reinforced concrete in railway construction

低碳碱活性胶凝材料（AACMs）具有显著降低混凝土环境影响的潜力（内含碳减少高达 **80%**）。然而，由于其使用性能的证据基础有限，因此供应商不愿意投资增加生产能力，因此其采用速度缓慢。主要问题之一是钢筋混凝土所需的长期耐久性数据对钢筋的保护水平，特别是在恶劣环境中。使用不腐蚀的玄武岩纤维增强材料（BFR）消除了这一风险。在GCRE现场试验中，BF增强AACM混凝土的示范和性能监测 ** 将提供 * 适用性 ** 的 ** 证据，解决用户/规范者的问题，提供数据支持标准制定，并鼓励供应链进行产能投资。该项目将进行可行性研究，以 ** 使AACM/BFR混凝土的最新创新与GCRE的混凝土结构应用保持一致 **。目标是开展第二阶段项目，在GCRE的优先应用中制造和“安装”使用AACMs和BFR制造的混凝土部件，并通过有针对性的测试计划提供支持，以更好地解决大规模使用的技术障碍。我们将在最近的国家高速公路M42运输道路项目的基础上，利用AACM地质聚合物混凝土和玄武岩纤维钢筋的组合，提供最小可行的嵌入碳解决方案，同时通过消除与钢筋相关的腐蚀风险来实现长期耐久性。线性和/或离散的挡土结构将是一个强有力的选择，尽管其他应用也将被考虑。该结构将采用传感技术，使我们能够验证应力与施加的载荷和设计预测，并使长期性能监测暴露于真实的世界风化和疲劳，并最终对这些新材料系统进行性能验证。**所产生的学习将为用户提供信心 **，并支持标准的制定。它还将使人们能够理解与大规模制造业相关的挑战，并重新设计供应链，以促进更广泛的应用。（玄武岩纤维加固），带柏油路面（使用AACM制造混凝土），斯堪斯卡公司（专注于铁路行业的建筑承包商），建筑研究机构（包括AACMs在内的水泥材料的耐久性和性能）和国家复合材料中心（结构性能监测、复合钢筋设计支持和可持续性）。

Low carbon alkali activated cementitious materials (AACMs) have the potential to significantly reduce the environmental impact of concrete (upto **80% reduction in embodied carbon**). However, their uptake has been slow due to the limited evidence base for their performance in use, with suppliers consequently unwilling to invest to increase manufacturing capacity.One of the main issues is the level of protection afforded to steel reinforcement with long-term durability data needed for reinforced concretes, especially in aggressive environments. The use of non-corroding basalt fibre reinforcement (BFR) eliminates this risk.**Demonstration and performance monitoring** of BF-reinforced AACM concrete in field trials at GCRE will provide **evidence of** **fitness-for-purpose**, addressing user/specifier concerns, providing data to support standards development and encouraging the supply chain to invest in capacity.The project will deliver a feasibility study to **align recent innovations in AACM/BFR concrete with applications for concrete structures at the GCRE**. The objective will be to carry out a Phase 2 project to manufacture and 'install' concrete components made using AACMs and BFR at priority applications at GCRE, supported by a targeted testing programme to better characterise and address technical barriers to use at scale. We will build upon the knowledge from our recent National Highways M42 haul Road project to utilise a combination of AACM Geopolymer concrete and Basalt fibre rebar to offer a minimal feasible embodied carbon solution whilst attaining long-term durability through removal of the corrosion risk associated with steel rebar. Linear and/or discrete ground-retaining structures would present a strong option although other applications will also be considered. The structure/s will incorporate sensing technologies to enable us to verify stress vs applied load and the design prediction and to enable long term performance monitoring exposed to real world weathering and fatigue and ultimately performance validation of these new material systems.**The learning generated will provide confidence** to users and support the development of standards. It will also enable challenges associated with the manufacture of larger scale manufacturing to be understood and supply chains to be reengineered to facilitate wider uptake.The feasibility study will be led by Bastech Ltd (basalt fibre reinforcement), with Tarmac (manufacture of concrete made using AACM), Skanska (rail sector-focused construction contractor), the Building Research Establishment (durability and performance of cementitious materials including AACMs) and the National Composited Centre (structural performance monitoring, composite rebar design support and sustainability).