Abstract:
This paper presents the results of the past research and a future plan of the ongoing research to improve the seismic behaviour of the Sliding Hinge Joint (SHJ), a low damage beam-column moment connection. The SHJ seismic behaviour depends on the sliding behaviour of the Asymmetric Friction Connections (AFCs), the energy dissipating components of the SHJ. In current practice, the AFC bolts are fully tensioned at installation. The experimental testing on joints with fully tensioned bolts has shown a significant reduction in the AFC post-sliding elastic strength due to the bolt tension loss. To reduce that effect and other potential causes of bolt tension loss after sliding, the use of Belleville springs (BeSs) has been proposed and experimentally tested, with the bolts installed within their elastic range. These findings are presented in this paper. A test setup has been developed to investigate the effect of the sliding surface finish on the AFC sliding behaviour. Different levels of surface preparation, covering the range of surface preparations that may be encountered in slip critical connections, have been tested to determine the optimum surface finish. A SHJ component test setup is being designed to determine the optimum way of using BeSs as well as the effect of having three rows of bolts in the SHJ’s beam bottom flange AFC. A test setup has also been designed to carry out the experiments to establish the method of bolt tightening with BeSs. The past and ongoing experimental plans are presented in this paper.
