Failure Modes of Bolted-Sheet-Steel Connections Loaded in Shear

Abstract

To ensure that accurate failure-mode assessments are made, and ultimately to ensure that accurate design equations are formulated, a detailed analysis is needed of the procedure used to identify the cause of a connection failure. Misidentification of failure modes and the misuse of data can lead to serious errors in the accuracy and applicability of design equations. The load-capacity formulations presented in the American Iron and Steel Institute (AISI) Specification cannot be used to accurately predict the failure modes of thin cold-formed sheet-steel bolted connections that are loaded in shear. A modification to the bearing-coefficient provisions, to account for the reduced bearing resistance of the connected materials, is necessary and has been proposed by the writers in recent papers. A revision of the net-section fracture design method is also required. Recommendations concerning the procedure that is used to identify the net-section fracture and bearing-failure modes are made in this paper.