Research On Seismic Behavior Of Nested Reinforced Concrete Shear Walls

Reinforced concrete shear wall structure is a kind of effective lateral resistant structure, and thus is widely used in high-rise buildings. However there are also many drawbacks in this structure type. Many researchers tried to improve the bearing and deformation properties of shear walls by changing the composition and form of the traditional shear walls, and some progress were made. Furthermore, many experimental studies have shown that redundant properties, seismic performance and collapse resistance of shear walls were unified to some extent.Researches in this thesis were focused on the performance and design of shear wall structures.Chapter â…¡ aims to improve the performance of shear walls by increasing its redundancy, thus five new types of reinforced concrete shear wall specimens were designed and put into cyclic test, in order to study the performance after a large destruction under earthquake. Test preparation and procedures are described briefly, and detailed analysis of bearing performance, failure mechanism, deformation and energy dissipation capacities of each specimen are proposed on the basis of test result. At last, the evaluation on the performance of the specimens is given, and those about how to obtain highly redundant shear walls are summarized to a general method as well.In the third chapter, those specimens tested in chapter â…¡ are nonlinear numerical modeled, and analysis of applicability of fiber model in shear wall modeling as well as part of the modeling guidelines is presented. Then previous research work of hysteretic model of reinforced concrete members is introduced, and the hysteretic model of WO-2is proposed after its hysteretic behavior is summarized through data fitting. Furthermore, the specimen can be well simulated by the model under cyclic loading, which is shown by comparison with the experimental results.The fourth chapter focus on the displacement based seismic design (DBSD). First, some problems in the capacity spectrum method for Chinese researchers are pointed out, and the need of improvements is explained. Second, the formula to generate inelastic demand curve for bilinear hysteretic model is derived, and inelastic demand curves for bilinear hysteretic models are therefore obtained based on the design response spectrum in seismic design codes in China. Third, the procedure for the capacity spectrum method used in DBSD is summarized and presented.