For prefabricated members, the reliable bonding of new-to-old concrete interface is the key to the formation of an integrated load-bearing system. Currently, both domestical and international scholars have conducted a series of studies on the static performance of the interface. However, the structures are often subjected to dynamic impact loads such as vehicle and ship collisions, heavy object impacts, and natural disasters during their service. Therefore, this paper studied the dynamic mechanical performance of the interface between new and old concrete in prefabricated structures. 210 prefabricated concrete components were investigated based on the split Hopkinson pressure bar test method. The research factors of this experiment include key parameters such as the average groove depth, the number of grooves, the interface inclination angle, and the combination of strength grades of new and old concrete, as well as the interface treatment methods (bonded rebar or not). The results indicate that factors such as the impact air pressure and the inclination angle of the specimen interface have a significant influence on the failure modes of the specimens, which can be classified into five categories based on the degree of damage and crack development characteristics. As the impact air pressure increases, the strain rate of specimens with different interface inclination angles gradually increases, with the 20° inclination angle specimens showing the most significant increase, while the 40° and 60° inclination angle specimens exhibit similar increases. With the increase in strain rate, the peak stress of all specimens shows an increasing trend. Under the same impact air pressure, specimens with a 40° interface inclination angle achieve relatively larger peak stress when the groove depth is greater, the number of grooves is higher, and the strength grade of the new concrete is increased. Bonded rebar can improve the peak stress of specimens under certain conditions. As the strain rate increases, the interface shear stress of all specimens also increases accordingly. Under the same concrete strength grade combinations, the shear stress of specimens with C1/C3 and C2/C3 is similar, both being greater than that of C1/C2. In particular, specimens with a 40° interface inclination angle exhibit higher shear stress at the interface. For specimens without bonded rebar, interface bearing capacity formulas were derived for three types: static-loaded without grooves, static-loaded with grooves, and impact-loaded with grooves. These formulas show good agreement with experimental results.

In order to study the seismic performance and reinforcement method of the wooden structure of Guangfu ancient building, two typical hoop tenon frames of Guangfu wooden ancestral halls with different structural forms were designed and manufactured by using merbau wood. A sparrow brace type damper for strengthening the tenon and mortise joints of the wooden structure was proposed and manufactured. Cyclic loading tests were carried out on the wooden frames before and after strengthening using the sparrow damper and the seismic performance of the structure and the reinforcement effect of dampers were studied. The results show that the damper can repair the damage caused by the cyclic loads, and provide higher initial stiffness in small rotation angle for the damaged mortise joint. It cooperates with the mortise joints well, so as to improve the joint stiffness, ultimate bearing capacity and energy consumption capacity, so that the ultimate bearing capacity of the reinforced specimens is higher than that of the unreinforced specimens. The unreinforced specimen show the phenomena of mortise and tenon separation and local compression buckling of mortise and tenon joints after loading, while the failure modes of the reinforced specimen are mainly mortise and tenon separation, local compression buckling of mortise and tenon joints, and vertical splitting cracks along the grain. The hysteresis curves of each joint show obvious "pinching" phenomenon. The strength degradation coefficients of all tenon joints are greater than 0.83, which shows stable bearing capacity under cyclic load. The ring stiffness and the equivalent viscous damping coefficient of each joint gradually decrease and tend to be stable with the increase of rotation angle. Equivalent viscous damping coefficients of the side-span frame specimen joints gradually stabilize from 0.1 to 0.2, while those of the mid-span frame specimen joints gradually stabilize from 0.05 to 0.1. With the reinforcement of damper, the total energy consumption of the mid-span frame specimen and the side-span frame specimen increases by 67% and 19%, respectively.

To provide theoretical basis for the restoration of Guangfu wooden structures, five hoop head tenon joint specimens were designed and manufactured using Merbau wood. Considering the influence of the size of mortise and tenon construction, quasi-static tests were carried out on undamaged and unreinforced joint specimens. Then, to preserve the original appearance of the building as much as possible, the damaged joint specimens mentioned above were reinforced by the Queti-type dampers that have minimal influence on the original appearance of the structure. Finally, quasi-static tests were conducted again on the reinforced joints to investigate the difference in their seismic performance and the strengthening effect of the dampers. The results show that the joint specimens reinforced with dampers exhibit significant indentations at the mortise and tenon connections when being loaded to failure. There is noticeable splitting on the outer side of the tenon of the beam and the detachment of the tenon, as well as obvious separation between the rubber and steel plate at the base of the damper. The addition of dampers to joints can compensate the decrease in forcebearing performance caused by initial damage, provide better post-damage stiffness for the damaged mortise and tenon joints, and enhance the ultimate load-bearing capacity and energy absorption capacity. After adding the damper, there occur enhancements in terms of post-damage stiffness, load-bearing capacity and energy absorption of specimens, as compared with the unreinforced joints, with the increment being more than 18%, 19% and 20%, respectively. Moreover, on the basis of the existing simplified mechanical model and in combination with OpenSees, a macro-modelling method was proposed for hoop head tenon timber structures, which helps to obtain hysteresis curves of the joints being in good agreement with the experimental results, meaning that the modelling method can effectively simulate the hysteresis energy dissipation characteristics of the hoop head tenon joints strengthened with dampers.