Study On The Seismic Isolation Performance Of Cam Response Amplification Viscoelastic Damper And Assembled Concrete Structure

Building isolation is to set the isolation layer between the bottom or upper floors of the structure,which can effectively reduce the natural frequency of the structure and the seismic response of the structure.Building isolation is a passive control system,which relies on seismic isolation bearings to absorb the energy dissipated by the seismic input and reduce the damage to the structure during the earthquake.The base-isolated building has the possibility of encountering extremely rare,which in turn leads to excessive displacement of the base-isolated layer.When the damper is used as the limit device of the seismic isolation layer,there will be a damper that may exceed its own ultimate deformation capacity under the action of extremely rare earthquakes.In order to avoid the above phenomenon,this paper has developed a new type of cam response amplification viscoelastic damper CRAD-VED(Cam Response Amplification Device of Viscoelastic Damper),the device can amplify the displacement of the viscoelastic damper at both ends,get more excellent Energy consumption effect.Under the action of extremely rare earthquakes,use it as a limit device and use it in series with the isolation support,which can effectively reduce the horizontal displacement of the isolation layer and achieve the displacement of the isolation support under the action of extremely rare earthquakes.purpose.This paper deduces the restoring force formula for the CRAD-VED device,designs and processes the CRAD-VED device and carries out pseudo-static tests,structural dynamic analysis,etc.The main work is as follows:1?By summarizing the advantages and disadvantages of the amplifying devices at home and abroad,a new type of cam-type response amplifying viscoelastic damper(CRAD-VED)was designed.The overall structure and operation mechanism of the device are introduced.The formula for calculating the restoring force,hysteresis curve and magnification of the CRAD-VED are deduced.It is theoretically concluded that the device can achieve the effect of the damper never exceeding the limit.2?According to the existing test conditions,the CRAD-VED test device was designed and processed.The initial performance test of the viscoelastic damper and the pseudo-static test of the CRAD-VED device were carried out.The hysteresis curve of the viscoelastic damper No.1 and the hysteresis curve of the CRAD-VED device were obtained.In order to solve the problem of the unequal maximum tensile force of the No.1 damper,the No.2 viscoelastic damper with the same parameters was designed and processed.The initial performance test and the pseudo static test of the CRAD-VED device were also carried out,and the corresponding hysteresis curve was obtained..The performance of the viscoelastic damper met the factory requirements in both tests,which verified the correctness and stability of the CRAD-VED's restoring force model.3?A single-degree-of-freedom uncontrolled system,a single-degree-of-freedom energy dissipation structure system with CRAD-VED installed,and a single-degree-of-freedom energy dissipation structure system with viscoelastic dampers installed separately have the same parameters.The single-degree-of-freedom structure Bouc-wen model analysis program,under the action of frequent earthquakes,rare earthquakes and extremely rare earthquakes,seven different seismic waves were applied respectively,and the control effect analysis,dissipated energy comparison analysis,response spectrum analysis,dynamic amplification of the three systems were carried out Coefficient comparison analysis.4?The YJK assembled concrete structure was converted into an ABAQUS model for the secondary development and verification of the CRAD-VED device and viscoelastic damper unit.The time-history analysis of the 10-layer prefabricated concrete frame structure shows that the control effect of the CRAD-VED device on the interlayer displacement angle,interlayer displacement,interlayer shear force and base shear force of the prefabricated structure is much better than that of viscoelastic damping Device5?Aiming at the problem that the maximum horizontal displacement of the seismic isolation layer exceeds the limit,CRAD-VED is attached to the seismic isolation layer as a limit device.This article uses MATLAB to compile two degrees of freedom isolation structure program.The control effect of the isolation layer and the superstructure of the three isolation systems and the energy dissipation effect of the device are compared and analyzed based on the damper force of the CRAD-VED device and the damper of the VED device under the action of achieving the horizontal displacement target of the same isolation layer.Comparative analysis.6?The 10-story prefabricated frame concrete structure was converted into seismic isolation concrete structure,and the seismic isolation prefabricated structure was established separately.The maximum displacement calculation of the isolation layer,the hysteresis curve analysis and energy analysis of the two kinds of limit devices,and the comparative analysis of the superstructure were performed under the action of rare and extremely rare earthquakes.