The Wind Resistance Study Of The Steel Frame Structural Main Factory Building Of Large Thermal Power Plant

The paper involved building overall finite element model of steel frame for spacial structure’s statical analysis and contrast model analysis, and also the dynamic response analysis under the action of fluctuating wind load by ANSYS and MATLAB. The results will be compared with the statical analysis ones. The research is technically supportive for the design process of large thermal power plant, with indefinite force transmission1000MW flight crew and irregular structural quality and stiffness arrangement. The results can also be the basis and reference for the design of equally huge and complex steel structures.The research results obviously provide data and conclusion for practical design and construction process. Otherwise, the research approach, that using the software of ANSYS and MIDAS/GEN for comparative analysis of the finite element of steel frame structures, is helpful to a more extensive meaning for the analysis and further research of the same structure type. First, the statical analysis of steel frame structure. After certain simplification for the structure, the three dimensional finite element model of steel frame is built according to the practical shape and size, receiving the internal force and deformation of the action of static force in consideration of combination of dead load, live load and wind load, etc. After deformation analysis under the action of wind is computed and the deformation is available, the final result can be applied in practical projects. Second, comparative modal analysis of overall steel frame structures. The author introduces the basic principle of modal analysis in Midas/gen, and conducts the analysis through two finite element models of overall steel frame, which separately take the sole wight of boilers and box girders of large span into consideration respectively by ANSYS and MIDAS/GEN.20ranks’model of vibration have been received, but only9in the front are presented in the paper. The third, seventh and ninth results of MIDAS/GEN analysis appear a whip effect, but the third and the other high order modes are not obvious of the effect, reflecting the difference between the two softwares relate to this kind of vertical and horizontal irregular steel frame structures. Response frequency0caused by dynamic wind load is bigger than the basic natural vibration frequency of the structure. The modal frequency after the sixth rate are similar with the response frequency θ, that the dynamic wind load has the potential of the risk of structure resonance. Last, based on the MATLAB, the author formulated the emluator of fluctuating wind speed time series by the method of linear regression filter, generating the wind speed time series which include average wind and fluctuating wind which are finally transformed as wind load time history acting on the streel bent frame. Then the transformed data will be imported into the ANSYS structural model, receiving the structural response time history after time-procedure analysis under the above wind load. The time-procedure results will be compared with the statical analysis ones and then can be applied in practical projects.