Structural and Fire Resistance of a Reusable Steel/Concrete Composite Floor System

全球能源和工业过程排放的二氧化碳中，有六分之一来自钢铁和水泥的生产，其中大部分用于建筑。尽管结构工程师越来越多地考虑降低结构的隐含能量，但由于现有的不同主流结构体系，无论是钢结构、混凝土结构还是复合结构，使用的原始材料数量相似，隐含能量值也相似，因此用今天的施工方法很难取得有意义的结果。我们提出了一种完全不同的方法来减少建筑对环境的影响：通过在结构寿命结束时使结构部件可重复使用。这可能会使新材料的使用减少50%。可重用结构组件的概念已经讨论过了，但是没有可行的解决方案。如果不使结构部件重复使用，在建筑物的使用寿命结束时，尽管建筑结构中的所有钢铁和混凝土材料仍然可用，但建筑物被破坏性地拆除，较大的钢铁元素通过能源密集型熔化回收，其余材料被填埋。这种建设方式显然是浪费能源、排放和潜在成本的。该项目旨在开发一种可重复使用的复合地板系统，用于钢/混凝土复合结构。重要的是，这种施工方法是作为一种主流的结构工程解决方案而发展起来的，而不是局限于非常特殊的条件，以便在寿命结束时最大化可重复使用的结构部件的设计和施工效益。之所以选择钢/混凝土复合结构，是因为这种建筑类型在英国最常用。拟议的可重复使用的地板系统是一种完全不同的建筑形式，具有以前从未研究过的结构行为的新模式。为了保证楼板系统的安全，需要对复合楼板的结构和防火工程设计进行全面的反思。计划对拟议地板系统的不同组件在环境温度和高温以及火灾下进行广泛的新物理测试，以确定系统的不同行为模式和失效。辅以广泛的数值模拟，该项目将深入了解新结构体系的结构和防火性能，以开发实用的设计方法。该项目将由布拉德福德大学和曼彻斯特大学合作进行，这两所大学在环境温度和火灾下的复合材料结构行为和设计方面拥有国际领先的经验，并拥有专门和经验丰富的研究团队和实验设施。一个由主要建筑公司的高层代表组成的指导小组将向研究小组提供意见，以确保研究的实际意义，并帮助推广研究成果。各种影响途径已被规划，包括项目的专门网站和设计师应用程序，将研究成果推广到相关的欧洲标准4（复合结构的欧洲标准）委员会（两位申请人，林教授和王教授，代表英国的结构安全（欧洲标准4第1.1部分，或EN 1994-1-1）和消防安全（欧洲标准4第1.2部分，或EN 1994-1-2）），并在项目结束时举行为期一天的研讨会。

One sixth of the world's CO2 emissions from energy and industrial process are released from the production of steel and cement, most of which is used in construction. Although reducing embodied energy in structures is increasingly being considered by structural engineers, it is very difficult to achieve meaningful results with today's construction methods because the different existing mainstream structural systems, whether steel, concrete or composite construction, use similar amounts of virgin materials and have similar embodied energy values. We propose a radically different approach to reduce the environmental impact of construction: by making structural components reusable at the end of life of the structure. This can potentially reduce the use of new materials of a structure by 50%. The concept of reusable structural components has been talked about, but no feasible solution is available. Without making structural components reusable, at the end of life of a building, although all the steel and concrete materials in the building structure remain serviceable, the building is demolished destructively, larger steel elements are recycled by energy-intensive melting, and the rest of the material is landfilled. This approach to construction is clearly wasteful - of energy, emissions and potentially cost. This project aims to develop a reusable composite floor system to be used in steel/concrete composite structures. It is important that this method of construction is developed as a mainstream structural engineering solution, rather than limited to very special conditions, so as to maximize the benefits of design and construction of reusable structural components at the end of life. Steel/concrete composite structures are chosen because this building type is the most commonly used in the UK.The proposed reusable floor system is a totally different form of construction, with new modes of structural behaviour that have not been investigated before. A complete rethink of composite floor structural and fire engineering design is necessary to ensure safety of the proposed floor system. Extensive new physical tests at ambient and elevated temperatures and in fire for the different components of the proposed floor system have been planned to identify the different modes of behaviour and failure of the system. Supplemented by extensive numerical simulations, this project will develop thorough understanding of the structural and fire performance of the new structural system to develop practical design methods. This project will be carried out in collaboration between the Universities of Bradford and Manchester, which have international leading experiences in composite structural behaviour and design at ambient temperature and in fire, and have dedicated and experienced research teams and experimental facilities.A steering group, consisting of high level representatives from key construction companies, will advise the research teams to ensure practical relevance of the research and to help promote the outcomes of the research. Various impact pathways have been planned, including a dedicated website for the project and APPs for designers, promotion of the research outcome to relevant Eurocode 4 (Eurocode for composite structures) committees (where the two applicants, Professors Lam and Wang, represent the UK for structural safety (Eurocode 4 Part 1.1, or EN 1994-1-1) and fire safety (Eurocode 4 Part 1.2, or EN 1994-1-2)), and a one-day colloquium at the end of the project.