Seismic Performance Analysis And Seismic Reinforcement Of Existing Zigzag Factory Buildings

Because of its natural lighting and easy ventilation,the zigzag structure factory has been widely used in printing and dyeing factories and textile factories.However,with the passage of time,the existing zigzag structure factory building is faced with the problem of seismic safety caused by the upgrading of production technology and the iteration of seismic code.Especially as a combination of equal height frame and unequal height frame,the seismic problem is more prominent.Therefore,it is of great significance to study the seismic performance of the existing zigzag structure factory building and strengthen it.By means of finite element analysis software SAP2000 modal analysis,response spectrum analysis,linear time-history analysis and nonlinear time-history analysis are carried out.This article mainly includes the following:(1)According to the inspection and appraisal report of Boshan Textile Factory,the plane layout,material properties and joint connection mode of the main workshop of the textile factory are determined,the three-dimensional spatial model of the existing sawtooth structure is established,and the modal analysis is carried out.The second mode of the existing structure is torsional mode,the ratio of the first torsional period to the first translational period is >0.9,the torsion phenomenon is obvious,and the structure arrangement is unreasonable.(2)Based on the detailed introduction of the theory of reaction spectrum analysis and the theory of time history analysis,the elastic analysis and elastoplastic analysis of existing structures are carried out.First,the response spectrum analysis shows that the deformation and internal force distribution of the structure are very different under different direction earthquake,and the seismic performance of the existing zigzag structure is evaluated according to the standard.Secondly,the linear time history analysis is carried out to verify the internal force distribution and deformation law of the existing structure.Finally,the nonlinear time history analysis is carried out to obtain the collapse law of the existing sawtooth structure,and it is found that the elastic-plastic displacement angle limit of the weak part of the single-layer bent structure can not be applied to the existing structure.The elastic-plastic deformation limit of sawtooth structure needs to be corrected.(3)Based on the seismic analysis results of the existing sawtooth factory building and the calculation assumption in the Design Code of Printing and dyeing Factory,a reinforcement scheme is put forward to change the connection mode between the wind tunnel beam and the corbel column.The reinforced single-layer hinge system enhances the integrity of the existing structure and improves the deformation control,but the deformation control still does not meet the requirements of the code.Therefore,the improvement measures suggest that the purpose of improving torsion and enhancing lateral stiffness can be achieved by redividing the elements and setting the support.