Application Of Steel Reinforced Concrete Composite Structure In Large Petrochemical Equipment Frame

Steel reinforced concrete composite structure has the advantages of high bearing capacity,high rigidity,seismic and fireproof performance,local and global stability of structure and so on,it has been widely used in engineering project in China,especially for civil buildings in an increasingly large proportion,more and more wide range of applications.In recent years,China's petrochemical industry has developed rapidly,more and more 10 million tons class refinery are set up.The size,self weight and production medium weight of the core equipment in the refinery multiplied.It brings great difficulties to the design of the frame structure supporting the core equipment.The space of the beam and column reduces the use space,which restricts the arrangement of the process equips and pipes.Large equipment frames are usually irregular structures,such as high stiffness,uneven stiffness and uneven size,which bring many difficulties to seismic design.At present,large petrochemical refinery equipment frame mainly adopts reinforced concrete structure,the paper takes steel reinforced concrete composite structures instead of reinforced concrete structure to optimize the design of beam and column section.In this paper,through the research,summary and study of frame structure of large equipment for the petrochemical industry and steel reinforced concrete composite structure,take the coke tower frame,which is the representative equipment of the coking unit,in the,reinforced concrete and steel reinforced concrete structure systems to set up modeling,calculate and analyse by two,STAAD PRO,SAP2000 three,Ying Jian Ke software.The main work and research results are as follows:1.The selection of materials and basic design provisions for steel reinforced concrete composite structures are reviewed;the calculation principle and method of steel reinforced concrete composite structural members are summarized,and compared with reinforced concrete structures: the contribution of section steel is taken into account in the calculation of steel reinforced concrete structural members,and the flexural capacity,compression capacity and bearing capacity of oblique section of the reinforced concrete members are greatly improved;in the calculation formula of deflection and crack,the contribution of section steel is also taken into account,and the calculation value is greatly reduced.The steel bearing rate of the section steel under the same condition is the key factor for the increase of the bearing capacity,the anti deformation and the crack resistance.2.Through modeling and calculation of coke tower frame for two kinds of structural systems,the conclusions are as follows:the composite steel concrete composite structure has the advantages of large lateral displacement stiffness,small axial compression ratio and high bearing capacity,when the steel ratio of steel reinforced concrete composite member with the same load and section size is 3%~10%,the natural vibration period,the horizontal displacement of structure,the displacement angle between layers and the deflection of flexural members can be reduced by about 20%;base shear increases 30% and so on;Through the section optimization design of the coke tower frame project example,when the steel ratio is about 10%,the cross section can be optimized about 25%;the decrease of the lateral stiffness of the coke tower frame increases the inter story displacement and reduces the seismic shear force,because of the higher bearing capacity and lower axial compression ratio,the steel reinforced concrete frame column still meets the requirement of the code limit and reduces the reinforcement ratio of the longitudinal stress steel bar.The steel reinforced concrete composite structure with reasonable steel ratio can improve lateral stiffness,reduce horizontal displacement and axial compression ratio of structure,and improve ductility and bearing capacity of structure,which is a good way to optimize section.3.By means of elastic time history analysis and supplementary calculation,the calculation results of the mode response spectrum method are verified and adjusted;.the elastic plastic time history analysis is used to analyze the base shear,the maximum floor response and the component damage of the coke tower frame;find out the weak layer,and draw the conclusion that the steel reinforced concrete composite structure has better seismic performance than the reinforced concrete structure,the excessive increase of the overall stiffness of concrete frames will increase the seismic shear force and increase the whiplash effect of the steel structure tower part.4.Through the calculation and analysis of STAAD PRO,Ying Jian Ke and SAP2000 finite element software,under wind load condition,the horizontal displacement is as follows: STAAD is the largest,SAP2000 is the minimum due to the different input modes of wind load;under the earthquake action condition,the horizontal displacement is as follows: SAP2000 calculation is the biggest,Ying Jian Ke is the minimum because of the different simulation methods of the equipment.It is concluded that two or more analysis software should be used for the analysis of the actual project,and the difference between the calculated results is analyzed,and the reasonable calculation results are selected for engineering design.