Mechanical Analysis Of Trussed Tower Boiler Steel Structure

Power station boilers are developing in the direction of large scale,large capacity and low emission.Because of good coal-type adaptability,small floor area and easy carrying of new technology,tower boilers have been more and more widely used.However,it is difficult to promote the usage of the large frame truss-type conventional tower boiler,which has four huge columns,to the inland.The main reason is that the core structure of the conventional boiler has huge members and joint plates,and causes problems in manufacture,erection and transportation.In this paper,the mechanical performance of a space trussed tower boiler is studied,which has the matching property of a conventional tower boiler to the boiler equipment.By changing the layout of the structure,increasing the number of structural components,the size of the members and joint plates is greatly reduced,and the manufacturing and erection difficulties of the tower boilers are reduced.Finite element software Staad.pro and SAP2000 were employed herein.A three-dimensional finite element model of space trussed tower boiler was established.The static analysis and modal analysis of the whole structure were conducted,and the response spectrum and the time history analysis under the seismic wave load condition were carried out.The analysis results provide the basis for the structural design of the tower boilers and the subsequent structural optimization.The main contents of this paper are as follows:(1)The static analysis of the steel frameA three-dimensional finite element model of space trussed tower boiler was established.The static analysis of the structure under static load,live load,wind load and combined load conditions is carried out.The static response of the structure is obtained,including the internal force of the members,displacement of the joints and reaction force of the foundation supports.(2)The modal analysis of the structureThe modal analysis of trussed tower boiler is conducted,and the natural vibration characteristics of the structure are analyzed,which is the preparation for the following vibration mode decomposition method response spectrum analysis and time history analysis.(3)The response spectrum analysis with mode decomposition methodThe seismic response spectrum of the structure is analyzed with mode decomposition method,and the response of the structure under the earthquake spectrum condition is obtained.(4)The time history analysisThe proper seismic waves for the site of the steel frame of the boiler is selected,and the dynamic response of the structure is analyzed by the time history analysis method.