Study On The Restoring Force Model Of The New Type Of End Plate Bolted Connections

In recent years,with the rapid development of the assembled concrete structure in China,the industrialization and industrialization of construction have become the focus of the construction industry.The development of prefabricated buildings is restricted by three factors : the seismic performance is weak,the construction technology and mechanical requirements are high,and the building can not be completely assembled.Assembly type structure,beam column joints is the main force transmission link,its performance determines the integrity and seismic performance of structure,so by means of research of beam column joints to improve the seismic performance of the prefabricated structure has great research value and practical value.In this paper,the end plate bolt group proposed based on two-way connection,configuration and dense prestressed reinforcement with high-strength stirrup shear design principles,designed a total of 8 specimens: 1 single prestressed rectangular concrete beams with ordinary stirrups,5 single rectangular prestressed high-strength stirrup concrete beams and 2 prestressed double stirrup rectangular concrete beams.Based on these specimens are cyclic quasi-static test,observe the specimen force deformation failure process and record test data.Through the observation and test data processing on the experimental phenomena,analyzes the stiffness degradation of node the specimen,strong The test results show that the spiral stirrup is beneficial to improve the bending resistance and shear resistance of the beam,the specimen has good ductility and energy dissipation capacity,and the seismic performance is good.According to the test results,the data processing and regression analysis,three linear restoring force model is established,and the calculation formulas are the corresponding stage,the stiffness degradation law of each stage of loading and unloading.The restoring force model of the skeleton curve and the test results were compared,two with a higher degree,which indicates the recovery force model can be used in the assembly structure elastoplastic analysis and seismic design.