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• Quasi-static tests were conducted on a self-centring connection with energy-dissipation plates of three sizes. • Seismic performance was excellent with concentrated structural damage and minor residual deformation. • Post-earthquake replacement of the energy-dissipation components was proven effective and efficient. • Finite element analysis was performed in both refined and simplified methods based on test validation. • Theoretical predictions on structural behaviour were verified by both experimental and simulated results. Structural resistance during the earthquake and the recoverability thereafter are of considerable concern in civil engineering. Localised damage is usually designed for easier post-earthquake repair or replacement, but a relatively low residual deformation is also required to make it truly viable. Based on that, this study mainly aims to propose a novel beam-column connection with self-centring capacity, and damage is concentrated on specific energy-dissipation plates that are replaceable to ensure rapid recovery after seismic events. The seismic behaviour of the target connection was investigated by quasi-static tests, and energy-dissipation plates of different sizes were replaced after cyclic loadings. Results showed that all specimens exhibited minor residual deformation and concentrated structural damage, indicating excellent seismic performance. The replacement of energy-dissipation plates was highly efficient, and structural responses were identical before and after replacing the plates of the same size. Numerical models were established in both refined and simplified methods to validate the experimental results, and further discuss structural responses with plates of different sizes. Moreover, a theoretical method for predicting structural behaviour was validated by both experimental and numerical results. The findings reveal actual seismic responses of the target connection in different geometries, and demonstrate the post-earthquake replaceability of the energy-dissipation components in practice. Besides, the analytical and simulated methods verified by actual behaviour can be extended for further analysis of the target system to understand and improve its seismic resilience. [ABSTRACT FROM AUTHOR]

• Quasi-static cyclic test was conducted on the self-centring connection after fire exposure. • Post-fire seismic behaviour changed significantly in geometric conditions and deformation mechanism. • Energy dissipation was postponed and weakened while self-centring capacity was completely damaged. • Finite-element analysis reappeared post-fire response after calibrating the highest temperature field. • Post-fire repair was simulated in sequence and practical suggestions were proposed based on effects. Fire hazard is regarded as a significant threat to structural systems, not only the resistance during the fire should be concerned but the post-fire assessment of structural performance is also of great importance. The post-fire seismic behaviour is the key metric for evaluating the residual performance of structures mainly serving seismic demands. However, limited research considers whether the self-centring system, one of the seismic-resilient structures, can still resist seismic loadings after fire exposure. Based on that, this study mainly aims to investigate the post-fire seismic response of a self-centring system with buckling-restrained plates and pre-stressed bars. A sequence of the fire exposure and the post-fire cyclic test was conducted on the cross-shaped specimen, and hysteretic behaviour after air-cooling was analysed and compared with the regular seismic response. Results showed that fire exposure not only significantly influences the geometric conditions of the self-centring system, but also completely transforms the original deformation mechanism. Pre-stressed bars were expanded and stretched during the fire so that could not provide self-centring capacity in post-fire conditions, while the energy dissipation of buckling-restrained plates was postponed and weakened because of the slippage at bolted connections. Compared with the regular seismic behaviour, the post-fire hysteretic response appeared sliding and pinching effect rather than the flag-shaped, with a much lower load-carrying capacity and extremely larger residual deformation. To improve the post-fire seismic resistance, the numerical model was established first to reappear the experimental response by the heat transfer analysis and post-fire static analysis, and then extended to simulate the post-fire repair in proposed strategies. According to the repair effect, it is suggested that the high-strength bolts should be replaced with pre-load, and the bars are required at least to provide additional stiffness and re-tensioned if necessary. The findings reveal the considerable influence of fire exposure on the seismic performance of the self-centring system, and highlight the importance of improving residual resistance of seismic-resilient structural systems in post-fire scenarios. [ABSTRACT FROM AUTHOR]