| Core walls have become major lateral force structure units in high-rise building. Although the frame-core wall structures have been widely used in china earthquake region, the theoretical analysis and design methods of core walls are few intensive studied and seismic performance of this kind of structure is poor. Therefore, it is of important theoretical and practical significance to study seismic performance of core walls. The main content is presented as follows.The failure mechanism and seismic performance of reinforced concrete core walls are studied. The low-cycle and reverse horizontal loading test of five reinforced concrete core walls specimens are carried out. The cracking process, yielding sequence, hysteretic behavior, bearing capacity, deformation and ductility properties, weak parts, stiffness degradation, energy dissipation capacity, section strain and shear lag phenomenon are investigated. The failure mechanism and force condition of plastic deformation are also analyzed. Meanwhile, the influence of height-width ratio, reinforcement ratio of coupling beam, span-depth ratio of coupling beam and loading action direction on the seismic performance of core walls under the same axial compression ratio are analyzed systemically. The Perform-3D software is adopted to perform static pushover analysis for reinforced concrete core walls, and results from the simulation match well with those from the tests. It is shown that the fiber model is valid for numerical simulation analysis of core walls. Damage development sequence of core wall specimen and yielding condition of each member are analyzed which coincide well with the experimental results. On this basis, effects of more design parameters on bearing capacity and deformation performance are systematically analyzed, and conclusions which is valuable for theoretical research and engineering design are obtained.Quantified Performance index and seismic performance evaluation of reinforced concrete core walls are researched. Based on current seismic code, four performance levels are put forward for reinforced concrete core walls which are respectively normal service, temporary service, life safety and collapse prevention. Based on statistical data of seismic performance test of core walls at home and abroad, limit states of the four seismic performance levels and dominating parameters for coupling beam and shear wall are put forward, and limit value of deformation performance for different failure modes are given. Meanwhile, story drift angle limitation for core walls under four performance levels is obtained. Seismic performance evaluation for reinforced concrete core walls based on incremental dynamic analysis (IDA) and demand-capacity factor method (DCFM) is investigated. The results indicate that the structure has excellent lateral resistant ability and reliability levels satisfying different fortification objectives are all over 90%. Comparison of the effects of one and multiple dimensional earthquake action demonstrate that the structural internal force under oblique seismic action is much stronger and the design results based on unidirectional earthquake input will be unsafe. The seismic performance of core walls based on single-record IDA method is analyzed under 45°with the Y-axis earthquake.Performance-based seismic design methods of reinforced concrete core walls structure are researched. Based on Capacity design theory the reasonable yield mechanism and failure mode of core walls is proposed. According to the work characteristics of coupling beams and shear walls, ultimate bearing capacity of core walls under severe earthquake are presented. The value calculated by the formula is close to the test value. According to concrete structure damage calculation model, capacity design method and capacity spectrum methods, based on the displacement of seismic design method and flow is presented. The seismic design of core walls is carried out by double controlling bearing capacity and displacement ductility.
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