Significance of the Deformation Capacity of Bolts for the Performance of Bearing‐Type Lap Connections

Abstract The study investigates the significance of the deformation capacity of bolts in bolted bearing lap connections, focussing on connections with aligned and misaligned bolt holes. The investigation includes a series of tests on S960 steel lap connections with M12 and M16 bolts of different bolt classes to evaluate the effects of misalignment of bolt holes and the ability of the bolts to redistribute forces. The test results of connections with aligned bolt holes show that the deformation capacity of the bolts was sufficient to equalise the bolt forces. However, the test results of connections with misaligned bolt holes indicate a potential reliability issue in the design of lap bolt connections where the ductility condition is not met, especially for high‐strength bolt classes, e.g. 10.9. The connections were characterised by premature failure of the bolt(s) as the deformation capacity of the bolt was used to overcome the misalignment of the bolt holes. These conclusions can be transferred to connections with lower steel grades, such as S235.