Design of extended & coped beam shear plate connections and welding of heavy plates and shapes

拟议的研究旨在改善加拿大结构钢剪切连接和利用厚板和厚轧制截面的焊接组件的知识、设计和详细规定的状况。ADF Group Inc.及其DPHV的工程师在应用现有设计程序时遇到了困难，并发现了这些连接和焊接组件的潜在性能问题。重型轧制型钢，通常被称为“巨型型钢”，其法兰厚度超过50毫米，并将成为本研究项目第一部分的主题。ADF Group Inc.最近制造的重型钢板组合箱形柱，使用了75毫米厚的钢板和带有双层板的重型轧制截面，导致大量开裂的成员不得不报废和重新组装。断裂发生在完全没有使用载荷的情况下，而是由收缩应力或热切割表面的残余应力引起的。据报道，整个行业的损失接近200万美元。由于加拿大的抗震和防爆设计，不同等级的钢材的使用正在增加，因此需要研究制定关于如何焊接这些重形状的详细建议。提出的研究的第二个组成部分解决了剪切标签连接的行为和设计。目前，加拿大钢结构研究所推荐的设计程序仅限于具有单柱螺栓的相对较小的配置。对于梁与梁之间的连接，无论是采用扩展的剪切板连接还是采用复制的梁与剪力板连接，都缺乏设计指南。轴向载荷在连接中与剪切结合的影响是特别有趣的。将进行具有代表性的剪切连接试验以及厚板和型材的材料试验。这将与剪切连接的有限元建模相补充，以评估更大范围的加载场景和重型截面的焊接程序。总的目标是推荐设计和焊接程序。

The proposed research directed towards improving the state of knowledge, design and detailing provisions in Canada of structural steel shear tab connections and of welded assemblies that utilize thick plates and heavy rolled sections. ADF Group Inc. and their engineers at DPHV have experienced difficulties in applying existing design procedures and have found potential performance issues with these connections and welded assemblies. Heavy rolled shapes, typically called "jumbo sections", with flange thicknesses exceeding 50 mm and built-up heavy shapes will be the subject of the first component of this research project. The recent fabrication by ADF Group Inc. of heavy steel plate built-up box columns that utilized 75mm thick steel plates and heavy rolled sections with doubler plates resulted in a significant number of cracked members that had to be scrapped and refabricated. The fractures occurred in the complete absence of service load, and were instead caused by either shrinkage stresses or by residual stresses on the thermally cut surface. The total industry loss was reported to approach $2M. Research to develop detailed recommendations on how to weld these heavy shapes is needed for different steel grades since their use is on the rise due to seismic and blast-resistant design in Canada. The second component of the proposed research addresses the behaviour and design of shear tab connections. The current design procedure recommended by the Canadian Institute of Steel Construction is limited to relatively small configurations with a single column of bolts. A lack of design guidance exists for beam-to-girder connections where either an extended shear tab or a coped beam-to-shear tab connection is used. The influence of axial load in the connection combined with shear is of particular interest. Testing of representative shear tab connections as well as material tests of the heavy plates and shapes will be carried out. This will be supplemented with finite element modeling of the shear tab connections to evaluate a wider range of loading scenarios and of welding procedures for the heavy sections. The general objective is to recommend design and welding procedures.