Research On Seismic Behavior Of Bolted Low Multiple-story Fully-assembled Concrete Structures With Equal Thickness Wall Panel

Since 2008,with the intensive introduction of national and local green building policies,China has set off a wave of prefabricated building construction.For a long time,the seismic performance of prefabricated buildings is a hot issue in engineering.Based on the localization of foreign mature technologies,this thesis proposes a bolted-connected fabricated concrete wall panel system suitable for 5-storey and below.The biggest advantages of this system are full prefabrication,full assembly and disassembly.Through pseudo-static test and finite element analysis technology,this paper studies the seismic performance of four groups of single bolted wall panels with equal thickness in the above system,and analyzes the influence of concrete strength grade,reinforcement ratio of concealed column longitudinal reinforcement,the number and diameter of high-strength bolts on the failure mode and seismic performance of wall panels.The main work and research conclusions are as follows :（1）This thesis introduces a fully assembled bolted concrete wall panel structure system which is suitable for buildings with 5 floors and below 8 degrees of seismic fortification intensity in China,and introduces the standardized design of wall panel,floor slab,wall column,horizontal beam and other components and their connection joints.（2）Pseudo-static tests were carried out on four groups of equal thickness wall plates connected by single bolt.The test results show that when the axial compression ratio is 0,the wall cracks are mainly horizontal tensile cracks.When the axial compression ratio is not0,the wall cracks are mainly bending shear oblique cracks.Bolts and corner areas on both sides of the bottom of the equal thickness plate are the key factors affecting the failure mode of a single wall plate.When the axial compression ratio is not 0 and the bolt strength is high,the corner area at the bottom of the wall plate is locally compressed.When the axial compression ratio is 0 and the bolt strength is low,the bolt is pulled.For the specimens with the same high strength bolt connection,the axial compression ratio has little effect on the failure mode.The axial compression ratio of this test was 0 – 0.053.In this range,with the increase of axial compression ratio,the horizontal bearing capacity of the specimen also increased slightly.When the axial compression ratio is 0,the hysteresis curve of the specimen is an inverse ’ Z ’ shape,and when the axial compression ratio is not0,the hysteresis curve of the specimen is an inverse ’ S ’ shape.With the increase of axial compression ratio,the area surrounded by the hysteresis curve increases,and the energy dissipation capacity increases.The displacement ductility coefficient of the specimen is about 2 – 2.5.（3）The finite element model of the specimen was established by ABAQUS.According to the failure mode and load – displacement angle curve of the specimen,the finite element calculation results were compared with the test results.The final failure mode of the specimen simulated by the finite element method was the same as the test results.The maximum relative error between initial stiffness and peak load is about 9 %,and the results were very close,which verified the reliability of the finite element model.（4）Based on the finite element calculation,the effects of concrete strength grade,reinforcement ratio of concealed column longitudinal reinforcement,the number and diameter of high-strength bolts on the failure mode and bearing capacity of the uniform thickness wall panel connected with single bolt were studied.The results show that within the range of parameters in this paper,the failure mode of the four groups of components has not changed,and it is still the local compression failure of the bottom corner of the wall panel.With the increase of concrete strength,the bearing capacity of the specimen is improved.With the decrease of the longitudinal reinforcement ratio of the concealed column,the failure range of the wall increases,and the decrease of the bearing capacity is not obvious.By increasing the number and diameter of bolts,the failure range of the wall increases and the bearing capacity of the specimen increases.