重庆市北碚区雷电气候特征及防护效率分析

On Analysis of Lightning Climatic Characteristics and Protection Efficiency of Beibei District in Chongqing

通过对北碚区闪电定位系统监测的地闪资料(1999-2008年)数理统计和回归分析,重点分析其时空分布特征及其防护效率.结果表明:北碚区年均闪电次数5 735次,其中负闪占93%,正闪占7%;闪电主要集中在6-8月,占总闪的73%,其中7月最多,占闪电总数的38%;雷电日数的月变化呈单峰变化;闪电次数的日变化呈多峰变化,两个峰值出现在22:00-00:00和4:00-6:00,次峰值出现在15:00-16:00;正、负闪均表现出明显的堆积效应,且正闪的聚集中心幅值小于负闪.北碚区建筑物直击雷防护按照1,2,3类防雷类别设计时,可能会出现0.02%,0.03%,1.41%的绕击率和0.14%,0.83%,3.51%的反击率发生.基于此得到北碚区雷电流幅值概率分布模式,为雷电防护设计施工提供科学参考.

With the data of lightning location system of Beibei ,the spatial and temporal distribution charac‐teristic and the protection efficiency of Beibei have been analyzed by means of mathematical statistics and regression analysis .The result show that the annual average lightning are 5735 in Beibei and 93 percents of that are negative lightning and 7 percents are positive lightning .73 percents of that concentrate on from June to August and 38 percents of that in July .The number of lightning day＇s monthly variation is single hump function and diurnal variation is multiple hump function ,two peak are twenty‐two o＇clock to twenty‐four o＇clock and four o＇clock to six o＇clock ,secondary peak is fifteen o＇clock to fourteen o＇clock .There is obvious pile up effect in positive and negative lightning ,and the gathering center amplitude of positive lightning is less than negative lightning .When the direct lightning protection of three classes structure have been designed ,the risk of shielding failure are 0 .02 percents ,0 .03 percents and 1 .41 percents ,and he risk of opposite shielding failure are 0 .14 percents ,0 .83 percents and 3 .51 percents .We get the distri‐bution pattern of the cumulative probability of lightning current ,and it provide scientific basis for lightning protection design and construct .