Development of generalised design procedures for steel extended shear tab connections

剪力节点是传统钢框架结构中最常用的剪力节点之一，由于其结构简单，造价相对较低。已经对标准剪力片进行了大量的研究，其中连接偏心较小，并且剪力片固定在相对刚性的支座上，如柱翼缘。因此，标准剪切片的设计方法已经很成熟，在钢结构中也经常使用。然而，可用于扩展剪切片设计的信息要少得多，如果可以通过延伸板来简化连接，以保持螺栓连接区域没有任何障碍，从而清洁连接配置和简单的安装技术，则需要扩展剪切片。 在将梁连接到柱腹板或梁腹板时，最常见的两种情况是在经济上需要扩展剪力片。在这些情况下，较长的剪切片清除了支撑柱或大梁的法兰，从而避免了为了安装和方便现场架设梁而需要处理梁法兰的需要。可以通过将翼片的顶部和底部边缘连接到支撑构件的水平板元件(连续板或法兰)来加强延伸的剪切翼片。 拟议的研究方案的主要目的是改进对扩展剪力片的性能和可能遇到的潜在极限状态的理解。这将通过全面的实验研究来实现，其中包括各种连接几何形状和加载条件，并以统一的方式评估观察到的连接性能。第二个但也是极其重要的目标是鼓励在传统结构钢结构中具有成本效益的连接，为促进更多地使用无加筋版本的加长剪力凸片提供动力。

Shear tabs are one of the most common shear connections used in conventional steel-frame construction due to their simplicity and relatively low cost. A significant amount of research has been done on standard shear tabs, where the connection eccentricity is small and the shear tab is affixed to a relatively rigid support such as a column flange. As such, design methods for standard shear tabs are well-established and they are used routinely in steel structures. However, far less information is available for the design of extended shear tabs, which are desirable for cases where joints can be simplified by extending the plate to keep the bolted connection region clear of any impediments to clean joint configurations and simple erection techniques. Two of the most common situations where extended shear tabs are economically desirable are when connecting a beam to a column web or to a girder web. In these cases, longer shear tabs clear the flanges of the supporting column or girder and thereby avoid the need to cope the beam flanges for fit-up purposes and for facilitating erection of the beam in the field. Extended shear tabs can be stiffened by connecting the top and bottom edges of the tab to the horizontal plate elements (continuity plates or flanges) of the supporting member. The proposed research program has as its overarching purpose the development of an improved understanding of the behaviour of extended shear tabs and the potential limit states that may be encountered. This will be achieved with a comprehensive experimental investigation that includes a variety of connection geometries and loading conditions, and evaluates the observed connection performance in a unified way. A secondary, but also extremely important, goal is to encourage cost-effective connections in conventional structural steelwork, providing an impetus for facilitating an increased use of the unstiffened version of the extended shear tab.