Mechanical Mechanism And Performance Analysis Of A New Self-centering Shear Wall

The self-centering precasted structures can be divided into the following several types: rocking structure,self-centering frame structure and self-centering shear wall structure.The self-centering structure is gradually developed on the basis of the rocking structure.the researchers added prestressed tendons to the rocking wall,and later,added internal or external energy dissipation structures for structural energy dissipation,the energy dissipation devices can be classified into two categories according to different layout modes.Therefore,the purpose of satisfying the self-centering function and the energy-dissipation function of the structure is achieved at the same time.The self-centering study in foreign countries is carried out earlier,and foreign scholars have carried out a more comprehensive study on self-centering structure.However,in China,there are still many blanks in the self-centering structure.At present,the research on self-centering shear wall in China is still in its infancy.In view of this situation,the hysteresis of the self-centering shear wall are mainly studied by this paper.Based on the design of common self-centering shear wall,the structure of shear wall is optimized.Different reinforcement modes of wall toes are tried to improve their self-centering performance and reduce the damage of the wall itself.The flexibility of the layout of prestressing tendons in shear walls is increased by studying the layout of prestressing tendons in shear walls.The main research contents are as follows:(1)The derivation of a hysteresis curve of the self-centering shear wall under the action of horizontal reciprocating thrust is studied,and according to different conditions,such as whether there is a wall side column,whether the corner reinforcement is carried out,and different layout of prestressing tendons,etc.The correction method of the theoretical formula is proposed and compared with the existing experiments to verify the accuracy and feasibility of the theoretical formula;(2)Based on the above research,this paper determines the modeling method of ABAQUS finite element model.Therefore,the modeling method of unbonded prestress,unbonded energy-dissipation steel bars and oblique prestressing steel bar is determined,and then the modeling mode of the overall structure is determined and compared with the existing experiments to verify the accuracy and feasibility of the model;(3)The structure,mechanical properties,energy consumption,self-centering and hysteretic behavior of traditional self-centering shear walls are analyzed.Structural optimization is done based on the above research.Inclined layout of prestressing steel bar can improve the flexibility of prestressing steel bar layout,while not affecting the overall performance of the wall.The effects of different reinforcement methods on the hysteretic behavior of the wall are studied,such as ordinary stirrup reinforcement,UHPC toe reinforcement or integral reinforcement mode of the lower layer of the wall.(4)In this paper,the finite element modeling is used to analyze the parameters of the self-centering shear wall structure to study the impact of deformation ability,damage condition,energy dissipation capacity,self-centering ability,hysteresis performance,resistance of each parameter to the self-centering shear wall and overturning ability,etc.The advantages and disadvantages of the new self-centering shear wall are studied to verify the feasibility of the new structure.