The RC short-pier shear wall structure is a new type of structural system in tall residential buildings. It has been applied in many buildings in China, but its seismic performance is worse than that of normal shear wall structures. Therefore, how to improve its seismic performance becomes a problem which has been paid much attention by engineers. In this paper, the seismic performance of short-pier shear walls with concealed bracing is investigated. An experimental study of four 1:3 scale coupled short-pier shear wall specimens has been carried out, two of which were normal coupled short-pier shear walls, and the other two coupled short-pier shear walls with concealed bracing. Based upon the experimental study, the effects of concealed bracing on the load-carrying capacity, stiffness, ductility, hysteretic behavior, energy dissipation and failure mechanism of shear wall are discussed. It is shown that the seismic performance of short-pier shear walls is greatly improved by concealed bracing. Finally, mechanical models for calculating the load-carrying capacity of the shear wall are proposed, and the theoretical results agree well with those from experiments.

Summary The metro‐induced vibrations and seismic safety are both big issues for historical buildings in modern cities. This paper proposed a novel hybrid vibration bearing (HVB) to isolate horizontal earthquakes and mitigate vertical metro‐induced vibrations. The HVB consists of lead rubber bearing and thick rubber bearing with decoupled horizontal and vertical behaviors. The mechanical model of HVB is developed, and a new vertical stiffness formula of thick rubber bearing is proposed to calculate the compression stiffness, without conducting test. A static test of the prototype HVB and a dynamic experiment of an SDOF system were performed. The bearing has stable behavior under different pressures and lateral deformations. The bidirectional test confirmed the decoupling characteristics. The isolation design and retrofitting of an overtrack historical building was conducted. After retrofitting, the average maximum vibration level and the average subfrequency vibration level decreased 25% and 18%, respectively. The horizontal accelerations of isolated structure were 65% to 70% of the input, and the shear strains of bearings were smaller than 200% under rare earthquakes. Finally, case study of structures with different types of foundations is introduced. The vibration mitigation efficiency of different structures is confirmed.

To improve the seismic performance of reinforced concrete core walls, reinforced concrete composite core walls with concealed steel truss were proposed and systemically investigated. Two 1/6 scale core wall specimens, including a normal reinforced concrete core wall and a reinforced concrete composite core wall with concealed steel truss, were designed. The experimental study on seismic performance under cyclic loading was carried out. The load-carrying capacity, stiffness, ductility, hysteretic behavior and energy dissipation of the core walls were discussed. The test results showed that the seismic performance of core walls is improved greatly by the concealed steel truss. The calculated results were found to agree well with the actual measured ones.