Seismic Performance of Rocking Column Joints with Friction Dissipation
Based on the concept of seismic resilient structures,a rocking column joint with friction dissipation was proposed.The configuration of the joint was presented and its seismic performance was investigated.The effects of parameters such as axial compression ratio and spring stiffness on the seismic performance and resilience of the joint under aftershock and restoration cases were analyzed through cyclic loading tests and numerical simulations.The study shows that the joint exhibits low-damage characteristics within±3%drift ratio.With the presence of axial force,the rocking column always remains elastic,and the hysteresis curve is obviously in a"flag-shaped"pattern.The joint possesses good self-centering performance,with a maximum residual drift of only 0.23%.By re-tightening the bolts,the joint performance can be restored to the level before seismic damage and achieve seismic resilience.The increase in spring stiffness can significantly improve load carrying capacity of the joint.The increase in axial compression ratio can improve both"yield"moment and ultimate bending moment of the joint.The joint is typically a semi-rigid joint under the action of axial force,and a range of initial rotational stiffness of the joint is determined.Finally,a simplified analytical model is proposed for the joint.The theoretical and experimental results are in a good agreement,which provides a reference for further analysis and design of the overall structure.