On the Applicability of the Loading Parameter PHI in Pinned Connections with Relevant Initial Clearance

In pinned connections, the presence of an initial clearance increases the lug stress concentration with respect to a neat fit configuration. By employing a recently proposed loading parameter Φ valid for plane models, the applied load and initial clearance effects on the stress concentration are normalised for a straight-shanked, round-ended, longitudinally loaded pin-lug connection of fixed outer to inner radius ratio. Results are obtained with a Mitchell-type, Fourier series solution and with commercial Finite Elements. The applicability of the loading parameter Φ to pinned connections with small to relevant initial clearances is explored. Two preliminary design charts are presented, which quantify the lug stress concentration factor versus the loading parameter Φ for two lug geometries defined by inner to outer radii ratios of 0.376 and 0.77.