Mechanical Properties And Seismic Reduction And Isolation Analysis Of Prefabricated Cooling Tower

With the continuous growth of power energy supply and demand in China,the shape of the cooling tower is also developing in a higher and larger direction,at the same time,the prefabricated structure has developed rapidly,steel structure is easy to realize building industrialization,it is becoming the selection and research direction of super large cooling tower.Cooling tower is the lifeline engineering object that needs to be protected in thermal power plant,if damage occurs in an earthquake,it will lead to the functional interruption of lifeline project and huge loss of social wealth,therefore,for the needs of improving the seismic capacity of super large cooling tower,it is necessary to apply vibration reduction and isolation technology to super large cooling tower,reduce the probability of structural failure under earthquake.However,there are few relevant research data on vibration reduction and isolation analysis of super large cooling tower structures at home and abroad,around this problem,in this paper,lead rubber isolation bearings and viscous dampers are applied to super large concrete cooling towers and prefabricated cooling towers,establishing finite element model with SAP2000,the damping effects of isolation and damping cooling towers under earthquake are compared and analyzed,mainly completed the following aspects:(1)The seismic response of super large concrete cooling tower with lead rubber isolation bearing is studied,the isolation design of a super large concrete cooling tower is carried out,the finite element models of base isolation and mid-story isolation cooling tower are established respectively,the structural dynamic characteristic analysis and nonlinear time history analysis are carried out,by comparing the dynamic characteristics and dynamic response of the structure,the changes of period and vibration mode before and after isolation are studied,the damping effects of base shear,relative displacement and acceleration amplification factor of the structure under frequent,intermediate and rare earthquakes are analyzed,the effectiveness of seismic isolation measures for improving the seismic capacity of super large cooling tower is verified,the advantages and disadvantages of two isolation measures are discussed.(2)The seismic response of super large concrete cooling tower with viscous damper is studied,The damping design of the super large concrete cooling tower is carried out,the finite element model of damping cooling tower is established,the structural dynamic characteristic analysis and nonlinear time history analysis are carried out,by comparing the dynamic characteristics and dynamic response of the structure,the changes of period and vibration mode before and after damping are studied,the damping and isolation effects of base shear,relative displacement and acceleration amplification factor of the structure under frequent,intermediate and rare earthquakes are analyzed,the effectiveness of damping measures for improving the seismic capacity of super large cooling tower is verified,the advantages and disadvantages of damping and isolation measures are discussed.(3)The seismic response of prefabricated cooling tower with lead rubber isolation bearing and viscous damper is studied,The damping and isolation design of a prefabricated cooling tower is carried out,the finite element model of isolation and damping cooling tower is established,the structural dynamic characteristic analysis and nonlinear time history analysis are carried out,by comparing the dynamic characteristics and dynamic response of the structure,the changes of period and vibration mode before and after damping and isolation are studied,the damping and isolation effects of base shear,relative displacement and acceleration amplification factor of the structure under frequent,intermediate and rare earthquakes are analyzed,the effectiveness of seismic isolation and dapping measures for improving the seismic capacity of prefabricated cooling tower is verified,the advantages and disadvantages of damping and isolation measures are discussed.