Study On Seismic Fragility And Life-cycle Costs Of Self-centering Concrete Shear Wall With Friction Devices

Self-centering concrete shear wall(SC Wall for short)with friction devices is a novel structure to control the seismic responses and to restore the original location after earthquakes.In order to study the mechanical behaviors of the SC Wall,nine low cyclic loading experimental tests and numerical study of the structure were conducted,which showed that the structure has expected excellent seismic performance.To promote engineering application of self-centering shear wall,seismic fragility analysis and life-cycle cost analysis for self-centering shear wall and conventional monolithic cast-in-situ reinforced concrete shear wall(short for RC Wall)were carried out.The main work are summarized as follow:(1)The configuration and main mechanical properties of SC Wall are introduced.Though nine low cyclic loading experimental tests,in which prestressing forces were applied to walls,the mechanical performance of the SC Wall was exmined.Influence of initial tendon forces of the walls,and friction forces on the mechanical behavior of the SC Wall was analyzed.The strain of embedded steel jackets at the toes of the wall were measured,the embedded steel jackets was proved to be necessary.The numerical simulation method is investigated by using the Open System for Earthquake Engineering Simulation(OpenSees),and good agreement is observed between the numerical simulation and the test results.A reliable numerical model is therefore obtained for the following seismic fragility analysis of the SC Wall.(2)Seismic fragility of SC Wall and RC Wall is analyzed.The principle of structural seismic fragility analysis and procedure of incremental dynamic analysis were presented.Amplitude modulation method of ground motion,intensity measure of ground motion and damage measure of structure,seismic performance level of structure are determined.Incremental dynamic analysis of the structure is completed based on forty selected earthquake records according to site classification.Discreteness of the data is evaluated by quantile curves.Seismic fragility curves are plotted in accordance with regression analysis of the data in order to evaluate seismic fragility of the two structures.(3)Life-cycle cost analysis of self-centering concrete shear wall is investigated,in conjunction with seismic fragility analysis results.The basic concept and stage division of life-cycle cost are introduced,and the principle and calculation model based on the failure probability are presented.Through comparative analysis of life-cycle costs between self-centering and cast-in-situ concrete structure,it is proved that the self-centering structure,as a novel structure,has more desirable seismic performance and life-cycle cost than the traditional structures.The above work provide references to promoting the increasing the seismic performance,reducing the structural damage and costs of post-earthquake rehabilitation.