SLIP COEFFICIENT AND CONTACT SURFACE CONDITION OF FRICTION TYPE OF HIGH STRENGTH BOLTED CONNECTIONS

Abstract

Slip coefficient of friction type of high strength bolted connections is well known to depend on the condition of contact surfaces. However, the coefficient is determined as 0.4 in the Japanese specifications for steel highway bridges, in which contact surfaces are to be rough without mill scale or have inorganic zinc rich paint. If the coefficient higher than 0.4 can be applied, the number of bolts and size of splice plates can be reduced. In this study, slip resistance tests on the joints with various contact surface conditions have been done, and a lot of existing data have been collected and assembled. On the basis of above examinations, slip coefficient is proposed in consideration of contact surface conditions.