Performance of the unified block shear equation for common types of welded steel connections

Abstract

Block shear describes a steel connection failure mode in which a combination of tensile and shear failures along perpendicular planes results in a block of material being displaced from a member. This behavior has been observed to govern the design of many bolted connections and has been well researched, resulting in design equations of various forms. Certain arrangements of welded connections are also susceptible to block shear. This paper reports on the potential application of a "unified" block shear equation, proposed by Driver et al. (2006) for bolted connections, to various welded connections. Experimental results for welded steel lap plate connections loaded concentrically in tension are examined. The results of these tests are used to describe the connection behavior and to evaluate the performance of several design equations, including the proposed "unified" equation. The application of the unified equation to welded connections of slotted hollow structural sections (HSS) and to coped beams supported at their ends by a clip angle welded to the beam web.