ABSTRACT
Slip resistance of slipped high strength bolted frictional joint is lower than that of un-slipped joint because the coating on the frictional surface is peeled partially by the slip. Coating thickness is one of the most important factors to estimate slip resistance. The coating thickness is usually measured by the film thickness meter. Measured thickness usually varies widely. Measurement method such as measurement position, the number of measurement times is not pre-scripted even if the target of measurement is un-slipped coating. In this study, slip experiment of bolted joint had been executed. Coating thickness on the frictional surface of not only the specimens before the experiment, but also those after the experiment is measured. The number of measurement times to satisfy an accuracy is discussed. Because the peeled degree of coating depends on the position on frictional surface, the measurement position on the frictional surface after slip is also discussed.
