New connection concepts for modular aluminum bridge applications

加拿大铝业已经认识到，建筑物和公共基础设施的应用领域是一个主要的收入来源，也是一个具有显著市场增长潜力的领域。在民用基础设施领域，随着业主和工程师越来越多地被迫解决与经典、低成本建筑材料相关的问题，例如循环荷载下的劣化和道路盐的大量使用，重大变化正在发生。铝具有重量轻、高耐腐蚀性和可挤压性，在这些特性最有益的应用中将取得重大进展，包括人行天桥和桥梁的模块化更换桥面。在此背景下，目前的研究建议集中在与连接设计相关的几个关键问题上，这些问题可能会对铝作为桥梁建筑材料的经济性和有效性产生重大影响。为了解决这些问题，提出了两个子项目：一个是关于“改善模块化铝人行天桥振动性能的新连接概念”，另一个是关于“用于铝桥面应用的免焊接连接”。在第一个子项目中，将使用一个足尺的模块化铝人行天桥试件来研究连接阻尼器对振动性能的影响。在这样做的过程中，连接特征，例如放置在连接构件之间的聚合物层的材料特性将被改变，以研究有意调节连接的减振特性以改善振动性能的新概念。在第二个子项目中，将研究一种新的滑动临界连接概念，该概念利用了铝挤压工艺提供的连接设计的多功能性。预计这项研究的结果将有助于提高铝在桥梁应用中的竞争力。利用这项研究结果开发的新产品不仅有利于加拿大的铝业(世界第三大铝业)，还将提高公有人行桥和车桥的耐用性，降低维护和用户延误成本。

The Canadian aluminum industry has recognized that the application area of buildings and public infrastructure represents a major source of revenue as well as an area with potential for significant market growth. In the field of civil infrastructure, major changes are underway, as owners and engineers are increasingly forced to address problems associated with classical, low-cost construction materials, such as deterioration under cyclic loading and heavy road salt use. With its light weight, high corrosion resistance, and extrudability, aluminum stands to make significant inroads in applications where these attributes are most beneficial, including pedestrian bridges and modular replacement decks for bridges. Against this background, the current research proposal focuses on several key issues related to connection design, which could have a significant impact on the economics and effectiveness of aluminum as a construction material for use in bridges. In order to address these issues, two sub-projects are proposed: one on "new connection concepts for improving the vibration performance of modular aluminum pedestrian bridges" and another on "weld-free connections for aluminum bridge deck applications". In the first sub-project, a full-scale modular aluminum pedestrian bridge specimen will be used to study the effects of connection damping on vibration performance. In doing this, connection features such as the material properties of a polymer layer placed between connected members will be varied to study the novel concept of intentionally tuning the damping properties of the connection to improve vibration performance. In the second sub-project, a new slip-critical connection concept will be investigated, which takes advantage of the versatility in connection design offered by the aluminum extrusion process. It is expected that the results of this research will lead to the improved competitiveness of aluminum in bridge applications. As well as benefitting Canada's aluminum industry (which ranks 3rd largest in the world), the new products that are developed using the results of this research will lead to improved durability and reduced maintenance and user delay costs for publicly-owned pedestrian and vehicular bridges.