Research On The Seismic Performance Of Coupled Structure-Equipment System Of Large Petrochemical Production Plant

Petrochemical production units are usually arranged with a large number of chemical equipment,which is characterized by a high overhang,vertical crossing,large volume,and weight,and are connected with the unit structure,forming a coupled unit structure-equipment system,generating dynamic interactions under seismic action and complex seismic response laws.In order to study the seismic performance of the coupled structure-equipment system of a petrochemical production plant,especially the dynamic characteristics and seismic response law of the major equipment in the system and the seismic design method,the equations of motion of the coupled structure-equipment system of the plant were proposed,and the values of the parameters in the equations were studied,three finite element models of individual reactor equipment,petrochemical plant structure,and coupled system were established,and the analytical study of the dynamic characteristics was carried out,and the seismic response law of the major equipment in the coupled system and the seismic response law of the individual equipment model were summarized in an in-depth analysis.A mean equivalent damping ratio floor response spectrum based on the seismic acceleration response at the equipment support in the coupled system was established as an input to the seismic analysis of the reactor equipment,and the seismic response of the reactor equipment was solved and co MPared with the seismic response results of the reactor equipment obtained in the coupled model time analysis to verify the reasonableness of the established floor response spectrum for the seismic design of the reactor equipment.The results show that the vibration frequency of the equipment in the coupled structureequipment system of the petrochemical production plant is smaller than that of the separate reactor equipment,and its vibration characteristics are also different,the maximum displacement deformation of the separate reactor equipment is located in the middle and upper part of the equipment,while in the coupled structure-equipment system of the petrochemical production plant,the maximum displacement deformation of the reactor equipment is located in the upper part of the equipment and the support;Under the same seismic loading level,the acceleration and displacement peaks of each monitoring point of the reactor equipment in the coupled system are larger than those of the individual reactor equipment,and the difference gradually increases with the higher loading level,and the peak equivalent force of the reactor equipment in the coupled system is much larger than the peak equivalent force of the individual reactor equipment,indicates that there is a strong dynamic interaction between the structure and the equipment in the coupled system and that the mutual influence between the equipment and the structure cannot be ignored in the seismic design of the structure-equipment coupled system of such devices,and that their dynamic coupling effects need to be considered in the seismic design of both the structure and the equipment,otherwise unreasonable conclusions may be obtained;The established mean equivalent damping ratio floor response spectrum is more applicable,and the error between the calculation results and the seismic response of the equipment in the coupled system is small.The seismic design method of reactor equipment using the mean equivalent damping ratio floor response spectrum method is more reasonable and can guarantee the seismic safety of the equipment in the structureequipment coupled system of such devices.