2025 Volume 71A Pages 503-514
The Specifications for Highway Bridges were revised in 2017 and stipulated for S14T, although the application is limited. The tightening force of S14T is higher than that of S10T, and there is concern about yield of the plates early. In addition, the contact pressure increases and the slip coefficient may decrease when the joint surface treatment is inorganic zinc. In this study, slip tests were conducted to deter-mine the effects of yield and contact pressure on the design slip coefficient of S14T high-strength bolt friction joint with inorganic zinc. It was concluded that the plate materials should be within the applicable of the Specifications for Highway Bridges, and that the design slip coefficient should be reduced to consider the effect of contact pressure when S14T is used with inorganic zinc.
