Seismic performance of steel semi-rigid friction-damped joints with replaceable angles in modern Chinese traditional-style buildings

As an important part of world-class architectural art, Chinese ancient timber architecture has a very high level of artistry and technology. However, these buildings have been seriously damaged in the long history. To inherit and reflect the national characteristics and regional culture, the modern Chinese traditional-style building (MCTB) is newly developed to imitate the appearance of Chinese ancient timber architecture. The base metal of the typical joint area in MCTBs is always fractured under earthquakes because of its rigid characteristics, which is difficult to repair once damaged. To prevent joint failure and improve reparability after earthquakes, steel semi-rigid friction-damped joints with replaceable angles in MCTBs are proposed. Four specimens were fabricated and tested under lateral cyclic loading. The test results showed that the failure of all specimens is mainly concentrated in the weak region of the replaceable angles. Compared with simple semi-rigid joints, the yield displacements of specimens with friction dampers (including shear damper and rotational damper) are obviously larger, and the strength, initial stiffness, cumulative energy dissipation and replaceable capacity are significantly improved. The improvement is more pronounced with the increase of the slip force of the dampers. Based on experimental results, the corresponding numerical models were established to optimize the structural design of steel semi-rigid friction-damped joints with replaceable angles in modern Chinese traditional-style buildings. •A design scheme of steel semi-rigid friction-damped joints in MCTBs was proposed.•Replaceable angles were designed and repairability of proposed joints was verified through tests.•The effect of shear/rotational dampers in steel replaceable semi-rigid joints was verified.•The optimal design solution of proposed joints in MCTBs was provided by FE simulation.