Seismic Behavior Of Coupled Shear Wall Structure With A New Type Of Self-Centering Coupling Beam

Shear wall structure is widely used in high-rise buildings,and coupling beams are the main energy dissipation components.Under the earthquake action,the coupling beams yield before the wall limbs and form plastic hinge energy dissipation.However,the failure mode of small span-to-height ratio coupling beams is brittle failure,which can not fully consume energy,and it is difficult and costly to repair the coupling beams after the earthquake,resulting in large economic losses.Although diagonal diagonal reinforcement can improve the performance of coupling beams,but the construction method is complex,construction is difficult,and it is still difficult to repair after earthquake.At present,the research of replaceable coupling beams is increasing gradually,but there are still some problems such as excessive residual displacement.In this thesis a new type of self-centering coupling beam is designed,which makes the coupling beam dissipate energy under earthquake action,and use its self-centering ability to reduce the residual displacement of the structure after the coupling beam deforms.In this thesis,the structure and working mechanism of the self-centering coupling beam are introduced,and the finite element model is established by using the Open Sees platform to simulate the new type of self-centering coupling beam and study the hysteretic characteristics of the self-centering coupling beam,the time-history analysis of 12-story coupled shear wall structures with ordinary reinforced concrete coupling beams,steel coupling beams and new type self-centering coupling beams is carried out to compare their seismic performance.The main findings and conclusions are as follows:(1)Firstly,a new type of self-centering damper is proposed,which uses a large-diameter Shape-Memory Alloy rod to provide self-centering capability and a friction damper to dissipate energy.Secondly,a new type of self-centering coupling beam is proposed,which consists of upper and lower chords and a new type SMA self-centering damper arranged diagonally.The hysteretic curves of the self-centering damper and the self-centering coupling beam show typical“Banner”type.The test curve of self-centering coupling beam is analyzed,which shows good energy dissipation and self-centering ability.(2)The design method of a new type of self-centering coupling beam is presented,and the formulas for calculating the shear bearing capacity,initial stiffness and residual displacement are given.The self-centering damper and the self-centering coupling beam are simulated by Open Sees software,and the test results are compared with the simulation results,the results show that the simulation results of self-centering damper and self-centering coupling beam are in good agreement with the experimental results,and the model accuracy is high.(3)The dynamic time history analysis of 12-story coupled shear wall structures with ordinary reinforced concrete coupling beams,steel coupling beams and self-centering coupling beams is carried out,comparing the story displacement angle,vertex displacement,coupling beam rotation angle,residual story displacement angle and residual coupling beam rotation angle of the structure under earthquake action,the results show that the displacement angle between stories,the displacement at the top and the rotation angle of the coupling beams are greatly reduced in the coupled shear wall structure with the new type of self-centering coupling beams.Compared with the coupled shear wall structure with steel coupling beam,the interstory displacement angle is increased,but the residual displacement is smaller,and the residual interstory displacement angle and the rotation angle of the residual coupling beam are greatly reduced.。...