The fully enclosed sound barrier of high-speed railway is a typical long-distance linear wind-sensitive structure that frequently faces the possibility of tornado attacks.In order to deeply understand the wind load characteristics of the structure under the action of tornadoes,a tornado field model was established based on the Ward-type tornado simulator principle with 2 km fully enclosed sound barrier on the Shenmao Railway as the subject.The structural wind load characteristics of fully enclosed sound barrier were analyzed accordingly under the different distances r of the sound barrier cen-ter from the tornado,the different moving angle paths of the tornado,and different ground vegetation coverage ratio η.The results show that wind pressure is the main wind load on the sound barrier's sur-face.Under a 0° movement path with η=0,the structure experiences significant overall wind pressure.The maximum negative wind pressure coefficient of-1.13 occurs at r=0,along with unfavorable drag coefficient CFx and lift coefficient CFx values of 0.27 and-0.49 respectively;At r/Rm=1(where Rm is the vortex core radius of the tornado field),the maximum positive wind pressure coefficient is 2.91,while the unfavorable moment coefficients CMy and are CMz 0.44 and 0.39 respectively;When designing the structure to withstand tornadoes,the circumferential pressure difference of the segment should be taken into account.It is recommended to combine 60％and 40％of the maximum positive wind pressure and 70％of the maximum negative wind pressure on the windward side,lee side and top of the struc-ture,respectively.
关键词
龙卷风荷载/全封闭声屏障/风压分布/风力系数/体型系数
Key words
tornado load/fully enclosed sound barrier/wind pressure distribution/wind force coef-ficient/shape coefficient
维普
万方数据