BOLTED CONNECTIONS SUBJECT TO SHEAR-OUT OR COMBINED BEARING AND SHEAR-OUT FAILURES

This paper points out that the ultimate load capacity of a serial bolted connection failing in combined bearing and shear-out cannot he computed as the simple sum of the respective ultimate bearing and ultimate shear-out capacities. It first describes an accurate equation for determining the ultimate shear-out capacity of a hot-rolled steel bolted connection. The shear-out equation is verified against independent laboratory test results, and are compared against equations specified in the American, European and Canadian steel design specifications. The various assumptions embedded in the existing equations, some optimistic and others pessimistic, are identified. The paper also presents an accurate hearing coefficient for a hot-rolled steel bolted connection. Based on the accurate shear out equation and the hearing coefficient determined by the authors, a design equation is proposed for determining the combined bearing and shear-out capacity of a serial bolted connection in hot-rolled steel plates. The proposed equation is demonstrated through verification against independent laboratory test results to be significantly more accurate than the simple sum.