Linear And Non-linear Finite Element Analysis Of The Meteorological Tower In Jiu Quan

With the development of economy and society in our country, all kinds of high-rise tower structures have been used more and more widely. Because there were lots of objections in the series-wound system in vertical direction which was used during the earthquake and wind analysis of high-rise tower structures, it was very necessary and valuable to study the behavour of high-rise tower structures. The finite element software SAP2000 would be used to build up and analyze the three-dimensional model of Jiu Quan meteorological tower for two purposes in this treatise, the first one was to service the project, and the other one was to offer some valuable references for the study of high-rise tower structures in our country.The following several aspects would be carried through to analyze the Jiu Quan meteorological tower. Firstly, the software SAP2000 would be used to analyze the dynamic behavour of the Jiu Quan meteorological tower which would be used to ascertain the number of model analysis and carry through elastic analysis to confirm the member sections and basement reactions. Secondly, in virtue of analyzing software MATLAB 7.0.4, the time history wind force in different height would be simulated which were used to carry through non-linear dynamic analysis for Jiu Quan meteorological tower so that the dynamic response of the tower would be gained. Thirdly, the dynamic non-linear analysis to the Jiu Quan meteorological tower under the anction of seldomly occurred earthquake would be carried through to ascertain the weak positons of the tower.Through the all-round and deep analysis to the Jiu Quan meteorological tower, the following several conclusions were drawn.: Firstly, the Jiu Quan meteorological tower is thin and tall, the nutural period of vibration was long, and so the wind loads and hozional earthquakes play a dominant role. Secondly, there are three tower platforms in the Jiu Quan meteorological tower along the vertical direction, and the stiffness and mass are not well-proportional. The analysis of dynamic behavour shows that there are several weak positions in the Jiu Quan meteorological tower, and it is necessary to conduct damping design to reinforce the resistance to earthquake and wind loads. Thirdly, because of the large lateral displacement, the P-â–³effect should be considered during the structural analysis of the Jiu Quan meteorological tower, so that the results of the analysis could be trustful. Fourthly, the study showed that compared with lower main structure, the lateral stiffness of the mast was rather weak, and the lateral displacement of the peak of the meteorological tower is large, so the whipping effect were very evident.