Turbulent Characteristic Parameter of Different Strong Wind Samples

In structure wind engineering, the accuracy of wind turbulent characteristic parameter is extremely important to the calculation of wind load of large structures. In the actual wind observation and analysis, the gale data are generally used to analyze the turbulent parameter characteristics, and more attentions are caught by the strong wind such as typhoon in coastal area. The calculation of wind turbulent characteristic parameter may be disturbed by an excessive attention given to the strong wind data. Moreover, the precision in the calculation of wind load may decline. In order to comprehend the impact of different strong wind samples upon the calculation of turbulent characteristic parameter values, an analysis and a comparison between two groups of wind speed samples are made. In the experiment, the CSAT3D three dimensional supersonic anemometer is used to observe the instantaneous wind speed from June to September in 2005 on the no rthern coast of Jiaozhou Gulf. About 605 hours effective wind observation data or 3631 subsamples are obtained in the experiment and divided into 10-min time step. The subsamples are divided into two groups according to different wind speed. One is called continual strong wind sample, in which the average wind speed during 10 minutes of each subsample is more than 8 m/s and the duration is more than 30 minutes. The other is called relative strong wind sample, in which the average wind speed of the subsamples is not always more than 8 m/s. The turbulent characteristic parameters of the two wind sample groups are calculated and a comparison between the two groups is made accordingly. It shows that though the average wind speed of continual strong breeze samples is about 37.6% more than that of relative strong wind samples, the average turbulent intensity of the relative strong breeze is 18%—23.5% smaller than that of the comparative strong wind samples, and the former average gust factor is more than 10%smaller than the latter, where as the former average friction velocity is 50% more than the latter. These results show that the value of wind turbulent characteristic parameter doesn't match the wind velocity well. Sometimes the wind velocity is small but its turbulent characteristic parameter value is big and vice versa. So, different wind velocity sample or different statistical methods may affect the calculation results of wind turbulent characteristic parameter.The calculation of wind turbulent characteristic parameter may be affected by an excessive attention given to the strong wind data. Moreover, the precision in the calculation of wind load may decline.