| Partially-restrained steel frame with reinforced concrete walls (PSRCW) is a new composite structural system, which possesses large stiffness and lateral strength. The uppermost advantage is that the bad damaged infill walls after earthquake can be replaced because the surrounding steel frame still keeps its integrality. These advantages show PSRCW structure is suitable as an earthquake-resistant system located in seismic regions. However, due to the complex interactive action between steel frame and infill walls, some behaviors are still needed to be studied continually, such as force distribution and transferring mechanism, failure modes and so on. Besides, the relevant investigation of PSRCW is vacancy in our relative structural code. So the study on the hysteretic behavior of PSRCW structure has important value on its theory and practice. This dissertation investigates systematically the hysteric behavior of PSRCW based on test, finite element and theory methods, and the main characteristic contribution is as follows:(1) Eleven one-bay, two-story test specimens on one-third scale are designed and tested under low reversed cyclic loading. The force transfer mechanism, failure mode, hysteretic behavior, stiffness degradation, deformation and ductility, and energy dissipation are discussed based on experimental results. The main design parameters of PSRCW are investigated, including of the type of shear connector, quantity of shear connector, reinforcement ratio, thickness and type of infill wall, type of PR connection and concrete grade etc.(2) The initial stiffness functions of story and overall structure are established on the basis of the experimental investigation and deformation analysis of PSRCW, and theory results agree well with the results of test.(3) Based on the virtual work theory and ideal plastic mechanism mode, plastic mechanism analytical method of PSRCW taking into account different lateral load distribution pattern is proposed. Theory calculating results conform well with real measuring ones, which indicates that plastic mechanism analytical method can be adopted to evaluate the maximum lateral strength of PSRCW structure.(4) As to the mechanical character of infill walls of PSRCW, inclined strip model is put forward, and is used to model the specimens of this dissertation. Through comparing with test results, this model can evaluate reasonably the general performance of PSRCW including of hysteretic behavior, strength, lateral stiffness, deformation and force distribution and so on. The proposed approach can avoid low simulating accuracy using micro finite element methods due to limitation of cyclic constitutive model for concrete, and reduces the total stiffness matrix, and improves resolution efficiency, thus laying a foundation for the study of the hysteretic behavior of PSRCW.(5) After verification of macro inclined strip model, a total of 26 specimens of 8 series are designed and simulated. The hysteric behavior, stiffness degradation, and force distribution etc of PSRCW are analyzed through taking into account the main design parameters including of thickness of infill walls, concrete grade, moment of PR connection, vertical load, height span ratio, and so on. Some advisable conclusions are proposed derived from this analysis.(6) Two phase design method of PSRCW is proposed at present. At the first phase, these sections of main component of PSRCW are determined according to elastic design method. At the second phase, surrounding steel frame with infill walls is calibrated based on the capacity design method in order to ensure that PSRCW produce ductile failure due to crush of infill walls and the maximum deformation capacity is obtained.
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