高低腿输电铁塔分体式防护大板抗地表变形性能研究

Research on Surface Deformation Resistance Performance of Split-Type Separated Protective Plates for Transmission Towers with High-Low Legs

以采动区山地边坡地带典型220 kV高低腿输电铁塔为对象,考虑塔腿级差(0,1,2,3 m)、大板厚度(200,400,600 mm)、地表变形方向(0°,45°,90°和135°)等因素,分析评估了新型分体式防护大板在地表水平拉伸、水平压缩、正曲率和负曲率作用下的抗地表变形性能。研究结果表明:分体式防护大板能有效降低高低腿铁塔的杆件内力和基础相对位移,且降低效果与地表变形类型、地表变形方向、塔腿级差密切相关;增大分体式防护大板的厚度可有效提高其保护效果,但当板厚增大到一定程度后其保护效果继续增大的趋势不明显,400 mm是分体式大板的最优厚度;当分体式大板的长度方向与地表水平变形或曲率变形的方向一致时,大板的抗变形性能可以得到充分发挥,而在其他方向的地表变形下效果相对较差。

In this article,A typical 220 kV high and low leg transmission tower with high-low legs in mountainous slope areas of mining areas was taken as the object,and factors such as tower leg difference(0,1,2,3 m),plate thickness(200,400,600 mm)and surface deformation direction(0°,45°,90°,135°)were considered to study the surface deformation resistance of the split-type protective plate under the action of horizontal tension,horizontal compression,positive and negative curvature of the surface.The results indicated that the split-type protective plate could effectively reduce the axial force and relative displacement of the foundation of the transmission high and low leg iron tower with high-low legs,and its protective effect was closely related to the type of surface deformation,direction of surface deformation,and tower leg level difference.The protective effect of the split-type protective plate increased with the increase of plate thickness,but when the plate thickness increased to a certain extent,its comprehensive protective effect no longer significantly increased with the increase of thickness.400 mm was the optimal thickness for the split-type protective plate to balance the protective effect and economy.When the length direction of the split-type large plate was consistent with the direction of horizontal or curvature deformation on the surface,the protective effect of the large plate could be fully utilized,but the effect was relatively poor under surface deformation along other directions.