In this article, the finite element method is used to build the analytical model of a traditional Chinese timber frame with straight mortise-tenon joints. The analytical model is then subjected to the lateral cyclic loading and verified based on the results of an experiment. Three types of damage in the straight mortise-tenon joint, including the gap between the mortise and tenon, damage in the top and the end of tenon, are proposed and idealized so that the analytical model can be modified accordingly. The hysteresis curve, stiffness and energy dissipation capacity derived from these damaged models with different damage extents are analyzed. The results indicate that the proposed damages of the joints have adverse influences on the lateral behavior of the timber frame. Both stiffness and energy dissipation capacity of the timber frame are weakened by these damages.

Transmission towers are an important component of the electric system, and their tall structural characteristics make them susceptible to failure under strong winds. Therefore, it is crucial to enhance the wind resistance of the transmission tower structures. This paper uses the finite element method to investigate the influence of a fixture-type reinforcement device (FRD) on the load-bearing performance of the transmission tower structure and explores the effects of different numbers of fixture pairs on the reinforcement. Based on this, the paper further analyzes the stress characteristics and failure modes of a typical tower structure under wind loads in two directions and investigates the influence of different reinforcement lengths on the wind resistance performance of the tower structure. The research results indicate that the FRD can effectively improve the deformation mode and failure characteristics of steel components under axial load. At the same time, using the FRD can effectively reduce the deformation of tower structures under strong wind, and only reinforcing three angled steel components can reduce the tower top displacement by about 55% and more.

The concrete shear keys, serving as the transverse displacement-limitation component between the superstructure and the substructure of the bridges, are prone to be damaged during the strong earthquakes. The use of the isolation bearings can mitigate the seismic responses of the bridge piers, but their excessive transverse deformation is also prominent and consequently can cause the complete failure of the shear keys. Aiming at enhancing the seismic performance of the isolated bridges under very rare earthquakes, a novel SMA-based sliding friction damper (SSFD) is proposed and simulated, which combines the SMA cables with the sliding friction mechanism. The hysteretic model of the SSFD is derived from theoretical analysis, and realized and verified through OpenSees. The design method is also proposed to determine the mechanical parameters of the SSFD so as to meet the seismic mitigation demand under very rare earthquakes. The verification study is then conducted to check the design method and evaluate the effectiveness of the SSFD in control the excessive displacement between the deck and the piers of an isolated bridge. The results show that the proposed novel SSFD can effectively reduce the bearing deformation with the mechanical parameters determined by the design method.