In this paper, the sliding properties of high-strength bolt friction joints with slot holes are investigated by slip tests and FEM analysis. This paper focuses on one-sided friction joints. First, slip tests were conducted to investigate the effects of each parameter: bolt hole shape, plate thickness, and stiffening plate shape on the slip coefficient. Next, FEM analysis is performed to investigate the effects of other parameters such as joint strength ratio, slot hole direction, thickness and shape of stiffening plate, and plate width on the slip coefficient. As a result, it was found that even if the stiffening plate is one size smaller than the base metal, it has little effect on the reduction of the slip coefficient. The effect of joint strength ratio and slot hole direction on the slip coefficient is also significant, and it is considered necessary to design the joints in consideration of these factors.
