Experimental Study Of The Behavior Of The High-strength Bolted Connections In High-temperature

The research is very important on the behavior and ultimate loading capacity of the structure, member, connection and material because the fire resistance ability of the steel structure is very poor. In abroad many tests and theory analysis have been carried out in this field, and the results have been used in code. In recent decade, great progress has been made in resist-fire research in China. But according to the reference, the research was mainly focused on the material, member and some structure. For the high-strength bolted connection, the fire resistance research is limited because the failure mechanism and mode are very complex. In China, the effect is not considered in the steel structure design code.In this paper, destroy to the buildings caused by fire and the fire resistance methods are presented. The effects of high-temperature to the behavior of the steel-frames are summed up. The high-strength bolted connections in tensile and shear are considered as the research object. A series of tests were done for the high-strength bolted connections in the high temperature circumstance. The failure modes and ultimate tensile and shear capacities were found in different temperatures and were compared with the results tested in room temperature and calculated according to the code. Test results show that when the high-strength bolted connections are in the high temperature circumstance, their tensile or shear rigidities and ultimate capacities will reduce, which will threaten the safety of the structures. This phenomenon should be considered in fire resistance design.The research work in this paper possesses some practical value and the test results can be provided as a reference for the similar research and the revision of the steel structure design code.