AN ANALYTICAL STUDY ON LOAD CARRYING CHARACTERISTIC OF HIGH STRENGTH BOLTED FRICTION TYPE JOINT WITH THICK FILLER PLATE

Abstract

 This paper focuses on the slip behavior of the high strength bolted friction type joint with thick filler plate and extreme thick connected plates. The filler plate is used to adjust the different thicknesses of the connected plates. It is known that the slip strength of the joint with thick filler plate is smaller than that of the joint without filler plates. To prevent to decrease of slip strength of the joint, the thickness of the filler plate is limited by Japanese Specification for Highway Bridges. By the way, the recent simplified structure of bridges makes the members large, including the filler plate of the joint, the thicknesses of the plates tend to be large. However, the investigations of the applicable range of the thickness of the filler plate focused on the extreme thick plates are not enough.
 In this paper, FEM analysis has been carried out to evaluate slip behavior of the joint. It is cleared that the smallness of the slip strength is related to the thickness change ratio, which is obtained as the ratio of the thickness of the filler plate to that of the thicker connected plate, rather than the thickness of the filler plate. And, especially in case the thickness of the filler plate is thick, unevenness of the friction stress around the bolt holes on the contact surface is one of the causes which make the slip strength small.