A basic study on the evaluation of residual axial force of high strength bolts for steel bridges constructed in the same environment at different ages

Abstract

In this study, the specifications of high strength bolts of different types and the friction surface treatment of the connection were different. According to the construction age, high strength bolts were extracted from two in-service two way steel bridges subjected to live loads, temperature changes, and environmental effects under the same environment and bridge type to ascertain whether the residual axial forces of the two bridges were maintained according to the design specifications.As a result of the investigation, it was found that the residual axial forces of the two bridges were almost all below the design values, except for a few. This decrease in axial force can be attributed; to the influence of the management of the tightening force at the time of construction, the structural type, the bolt type, the friction joint surface treatment, etc.