采动区输电塔线体系在不同方向地表水平变形下的抗变形性能研究

STUDY ON ANTI-GROUND-DEFORMATION CAPACITY OF TRANSMISSION TOWER LINE SYSTEMS IN MINING AREAS IN DIFFERENT DIRECTIONS SUBJECTED TO HORIZONTAL GROUND DEFORMATION

为了评估煤矿采动导致的水平地表变形对输电线路的安全威胁,以220 kV线路中的输电塔线体系为研究对象,运用有限元软件ANSYS,建立了输电塔线体系的有限元模型,考虑水平地表变形的类型、方向,分析铁塔杆件受力的变化规律,揭示铁塔的破坏模式与地表水平变形的相关关系。研究表明:在水平地表变形下,铁塔以第一横隔支撑面附近的交叉斜杆、横隔材等杆件的屈曲为主要的破坏标志;地表水平变形的方向对铁塔的破坏模式和抗变形能力都有显著的影响;与顺线路方向和垂直线路方向的水平地表变形相比,当水平地表变形沿着斜方向作用时,铁塔的抗地表变能力明显降低,且当夹角为45°时达到最小。

To evaluate the threat of horizontal surface deformation caused by mining to the safety of transmission lines,a typical 220 kV transmission tower line system was taken as the research object and its finite element model was constructed by ANSYS.Considering the types of horizontal surface deformation,and directions,the change laws of forces in the tower members were analyzed,and the relations of the failure mode of the tower and the earth’s surface horizontal deformation were revealed.The results showed that the buckling of the cross braces and horizontal braces in or near the first diaphragm-bracing plane was the main failure sign of the tower subjected to horizontal surface deformation.The directions of the horizontal ground deformation had a significant impact on the failure modes and deformation resistance of the tower.Compared with the horizontal ground deformation along the line or perpendicular to the line,when the horizontal ground deformation occured at an oblique angle to the line,the anti-ground-deformation capacity of the tower was significantly reduced,and the minimum capacity was at an oblique angle of 45 degrees.