采动区地表变形对输电铁塔抗风性能的影响研究

RESEARCH ON THE INFLUENCE OF GROUND SURFACE DEFORMATION ON THE WIND RESISTANCE OF TRANSMISSION TOWER IN MINING SUBSIDENCE AREA

为研究采动区地表变形对输电铁塔的抗风性能的影响,以典型的110 k V输电铁塔为例,建立有限元模型,分析在不同类型地表变形下铁塔在风荷载作用下的破坏特征,获得了铁塔极限风荷载与地表变形的相关关系。研究表明:输电铁塔的抗风极限承载力随着地表水平变形值的增大而减小,且地表变形值越大,抗风极限承载力的减小幅度变化越明显;与垂直于风荷载方向的地表水平变形相比,当地表水平变形的方向与风荷载方向相同时,输电铁塔抗风性能的下降更为明显;地表水平拉伸变形对输电铁塔抗风性能的不利影响比地表水平压缩变形更为明显。单支座的竖向下沉对铁塔抗风性能的不利影响非常显著。

In order to study the influence of ground surface deformation on the wind resistance of transmission tower in mining subsidence area,a typical 110 kV transmission tower was taken as an example to establish the finite element model of the tower.Considering the effect of different types of ground surface deformation,the failure characteristics of tower under wind load were analyzed,and the relationship between ultimate wind load and surface deformation was obtained.The results showed that the wind resistance ultimate bearing capacity of the transmission tower decreased with the increase of the horizontal ground surface deformation value,and the larger the ground surface deformation value was,the more obvious the decrease of wind-resistant ultimate bearing capacity was;compared with the horizontal ground surface deformation in a direction perpendicular to the wind load,the decrease of the wind resistance of transmission tower was more obvious when the horizontal ground surface deformation direction was the same as the wind load direction.The adverse influence of horizontal tensile deformation on the wind resistance of transmission tower was more obvious than that of horizontal compression deformation.The adverse influence of the vertical subsidence of a single support on the wind resistance of transmission tower was very significant.