Research On Dynamic Characteristics And Seismic Performance Of Petrochemical Production Plant With Vertical Hybrid Structure System

A commonly used structur l form in petrochemic l production f cilities is the steel-concrete vertic l hybrid structure,which cont ins l rge mount of equipment with high volume,weight,nd v lue rr nged vertic lly cross multiple floors,forming the steel-concrete vertic l hybrid structure-equipment system.Currently,there re no specific guidelines for seismic design of this type of f cility structure-equipment system,resulting in n engineering dv nce nd theoretic l l g phenomenon th t requires further investig tion.In view of the specificity nd complexity of seismic s fety of such structure-equipment systems,considering the inter ction between the structure nd equipment,this p per proposes theoretic l c lcul tion model suit ble for dyn mic n lysis of the structure-equipment system nd est blishes finite element model for the vertic l mixed structure-equipment system in petrochemic l production f cilities.The influence of different stiffness r tios nd m ss r tios of the upper nd lower structures on the dyn mic ch r cteristics of the structure is n lyzed,b sed on ex mples from petrochemic l production f cility projects,including cceler tion response,displ cement response,stress response,l ter l deform tion ch r cteristics,nd we k points in the seismic resist nce of the structure-equipment system.The study provides scientific b sis for improving the seismic s fety of l rge-sc le petrochemic l production f cility vertic l mixed structure-equipment systems.The rese rch results show th t when conducting dyn mic response n lysis of the steel-concrete vertic l hybrid structure-equipment inter ction,not only should the imp ct of equipment on the m in structure be considered but lso the influence of the mixed l yer of the m in structure.The gre ter the m ss r tio of the upper nd lower structures in the vertic l mixed structure-equipment system of petrochemic l production f cilities,the sm ller the vibr tion frequency nd the longer the period.All four models exhibit equipment-domin ted vibr tion ch r cteristics st rting from the fourth order,nd petrochemic l equipment h s signific nt imp ct on the low-order mode frequency of the over ll structure of the production f cility.The difference in stiffness r tio of the upper nd lower structures h s little effect on the vibr tion frequency of the structure-equipment coupling system.The period r tio of models with different m ss nd stiffness r tios is less th n 0.85,but very close to the limit,indic ting th t the torsion l effect h s signific nt imp ct on the entire f cility.When the ch r cteristic period of the input seismic w ve is close to th t of the upper steel structure,the cceler tion response nd displ cement response of the upper steel structure will re ch their m ximum v lues.The l ter l stiffness of the petrochemic l production f cility structure ch nges signific ntly in the tr nsition l yer,nd the inst ll tion of equipment on the fifth floor le ds to signific nt incre se in pe k displ cement,which signific ntly ffects the seismic response of the structure.Under different seismic w ve ctions,the m ximum interl yer displ cement occurred t the second nd third floors with high story heights nd the fifth floor where the equipment w s inst lled,nd the lower concrete structure exhibited she r deform tion ch r cteristics.The connection between the equipment nd structure dopts fixed form nd is the loc tion of stiffness nd m ss mut tion in the structur l system,with stress pe k of 5.61?10~7Pa.Therefore,speci l ttention should be p id to the design nd construction of the tr nsition l yer nd equipment support to ensure their s fety in the mixed structure.