Corrosion resistant composite bridges using stainless steel I-sections and shear studs

本项目研究不锈钢工字形截面和剪力钉在钢-混凝土组合桥梁中的应用。由于恶劣的环境、大/可变的结构荷载以及对桥梁所在场地的限制，桥梁结构给承包商和结构设计师带来了许多挑战。这些结构的建造和维护可能是及时和昂贵的，特别是在存在盐和水的环境中。不幸的是，在过去的一些情况下，如康涅狄格州的Mianus河大桥，桥梁中某些元素的腐蚀导致了结构倒塌和生命损失。钢-混凝土组合梁包括通过剪力连接件连接到混凝土板的钢I形截面，广泛用于建筑物和桥梁中，因为该系统优化了每种材料的使用，并使梁能够无支撑地跨越长距离。然而，迄今为止，大多数研究都集中在这些应用中的碳钢上。传统上，不锈钢由于其较高的材料成本和有限的可用设计指导而不太受欢迎。近年来，研究人员也越来越多地将注意力转向这种材料，从而更好地了解其结构特性和性能。与碳钢相比，不锈钢具有许多优点，最显著的是上级耐腐蚀性。这减少了对桥梁维护的需求，因此较高的材料成本可以通过较低的生命周期成本来补偿。这种改进的耐腐蚀性也降低了结构故障的可能性。本研究项目的目的是对不锈钢-混凝土组合试件进行一系列实验室试验（推出试验和全构件弯曲试验），使用不锈钢I形截面和剪力钉，以评估不锈钢的性能。实验将在布拉德福德大学结构工程实验室的坚固地板上进行。比较不锈钢和碳钢部件的性能。还将比较不同类型的抗剪螺柱-焊接和螺栓连接/可拆卸。可拆卸的剪切螺柱在易于构造/拆卸方面提供了进一步的潜在优势，并且在疲劳载荷下比焊接螺柱具有潜在更好的性能。在实验之后，将使用有限元软件开发数值模型，以扩展研究结果并进行参数研究。研究结果最终将用于制定纳入欧洲规范4的指南，促进不锈钢的开发，以提供更安全，更具成本效益和更低维护的钢-混凝土组合结构。

This project investigates the use of stainless steel I-sections and shear studs in steel-concrete composite bridges. Bridge structures present many challenges to contractors and structural designers owing to harsh environments, large/variable structural loading and limited access to the sites in which they are often located. Construction and maintenance of these structures can be timely and expensive, particularly in environments where salt and water are present. Unfortunately, on some occasions in the past such as the Mianus River Bridge in Connecticut, corrosion of certain elements in bridges has led to structural collapse and loss of life. Steel-concrete composite beams, comprising a steel I-section connected to a concrete slab by shear connectors, are widely used in buildings and bridges since this system optimises the use of each material and enables beams to span long distances unsupported. However, most research to date has focussed on carbon steel in these applications. Stainless steel has been traditionally less popular owing to its higher material cost and limited available design guidance. Researchers have also increasingly turned their attention to this material in recent years, leading to a better understanding of its structural properties and performance. Stainless steel offers many advantages over carbon steel, most notably superior corrosion resistance. This reduces the need for bridge maintenance and so the higher material cost is compensated for by lower life-cycle costs. This improved corrosion resistance also reduces the likelihood of structural failure. The aim of this research project is to conduct a series of laboratory experiments (push-out tests and full member bending tests) on stainless steel-concrete composite specimens using stainless steel I-sections and shear studs in order to assess the performance of stainless steel. The experiments will be conducted in the strong floor in the structural engineering laboratory of the University of Bradford. Comparisons will be drawn between the performance of stainless steel and carbon steel components. Different types of shear stud will also be compared - welded and bolted/demountable. The demountable shear studs offer further potential advantages with regard to ease of construction/dismantling and a potentially better performance under fatigue loading than welded studs. Following the experiments, numerical models will be developed using finite element software in order to extend the results of the research and enable parametric studies. The results will eventually be used to develop guidelines for incorporation into Eurocode 4, promoting the exploitation of stainless steel to provide safer, cost-effective and lower maintenance steel-concrete composite structures.