Study On Dynamic Response Of Wind Power Tower Structure Under Seismic Wave

Located in the frequent earthquake occurrence zone of Eurasia Plate, Chinahas the high frequency of earthquake occurrence. According to the previous formsof damage, three main structure failure modes that caused by earthquake arebending failure of tower drum, foundation detachment from tower drum andintegral destroy of the structure caused by excessive deformation in placket zone.For the wind power tower is a typical top-weight-bottom-light thin-walled andhigh-rise structure with plackets in the bottom which causes reducinghardness, itis more likely that toppling failure occurs when the structure’s bendingdeformation is too large caused by the structural vibration. Consequently, thestudy on dynamic characteristics analysis and earthquake dynamic responseanalysis of wind power tower structures has great significance.Now, the studies of wind power facilities are mainly about the generationsystem such as blades, impellers and generators, and the influence of dynamicpower by wind wheel on the engine room control system. And the studies of windpower tower support structures are mainly about static analysis and dynamicanalysis under seismic action of tower drum. As a matter of fact, the studies on theinteraction of wind power tower support structures are less presented, especiallyconsidering the influence of soil on support structures and the dynamic responseunder the interaction of wind load and earthquake.In this study, according to the industry standards, national standardspecifications and related high-rise structure theories about wind power towersupport structures at home and abroad, the influence of the horizontal earthquakeload which distributes along the height of tower drum on the bearing capacity ofwind power tower was studied. Also, the comparative analysis of researchesresults in different calculation methods at home and abroad was carried out, andthe optimal calculation method of the horizontal earthquake dynamic wasproposed. The dynamic time-history analysis of this structure under different inputangles of seismic wave and different types of seismic waves (long period seismicwave and short period seismic wave) was also carried out. After that, the influenceanalysis of different input angles of seismic wave on the failure of the structurewas made and the most unfavorable input position of seismic wave was found.Furthermore, the study of dynamic characteristics of wind power tower support structures under the combination of wind-earthquake load was completed. Theinfluence analysis of the random combination of wind-earthquake load under theunfavorable condition of structural displacement, acceleration response,maximum stress and strain points was summarized. Lastly, considering theinfluence of soil to the structure under the earthquake action, the comparison ofnumerical results in two different kinds of methods was made.