New connection concepts for modular aluminum bridge applications

加拿大铝业已经认识到，建筑和公共基础设施的应用领域是一个主要的收入来源，也是一个具有巨大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传统的低成本建筑材料相关的问题，例如在循环荷载和大量道路盐使用下的劣化，正在发生重大变化。凭借其重量轻，耐腐蚀性高和可挤压性，铝在这些属性最有利的应用中取得了重大进展，包括人行天桥和桥梁的模块化更换甲板。在此背景下，目前的研究建议侧重于与连接设计相关的几个关键问题，这些问题可能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“铝桥面应用的无焊接连接”。在第一个子项目中，将使用一个全尺寸的模块化铝人行天桥样本来研究连接阻尼对振动性能的影响。在这样做时，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，以研究有意地调整连接的阻尼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提高铝在桥梁应用中的竞争力。除了使加拿大的铝工业（世界第三大铝工业）受益外，利用这项研究结果开发的新产品将提高公共行人和车辆桥梁的耐久性，降低维护和用户延迟成本。

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.