In this paper, an evaluation formula of friction coefficients on bolted joints with aluminum-sprayed splice plates is derived from the results of basic slip tests. It shows that the lower the averaged values of contact pressure which depend on thickness of splice plates, diameter of bolts and tension of bolts are, the higher friction coefficients of bolted joints are. The results of the slip tests of bolted joints show the same relation between the averaged values of contact pressure and friction coefficients of bolted joints.
