Relaxation in High-Strength Bolted Connections with Galvanized Steel

摘要

In recent bridge construction in Connecticut, significant relaxation was found inhigh-strength bolted connections with galvanized plates, where the coating thickness was approximately 13 mils. There was concern that this could result in a significant in shear capacity. The current AASHTO Specification is based on research conducted with coating thicknesses not greater than 6 mils. In this research, tests were conducted to study the relaxation and shear capacity of the high-strength bolted connections with galvanized coating thicknesses ranging to 20 mils. Both normal and oversized holes were studied. The amount of relaxation associated with the coating thickness was determined experimentally. the shear capacity of the connections with the thicker coating reduced due to the loss in clamping force. The test results have been used to develop design guidelines.