小根开细柔输电杆塔抗风可靠性研究

Research on Wind-resistant Reliability of Slender Transmission Tower with a Small Root Span

研究了强风作用下小根开细柔输电杆塔的抗风性能。首先建立了输电杆塔的等效随机风荷载模型。随后通过建立输电线张力表达式,考虑了输电线对杆塔的作用。进一步地建立了小根开细柔输电杆塔的抗风可靠性计算方法。基于实际工程结构研究了杆塔在不同强度风荷载用下的抗风可靠性问题。结果表明:小根开细柔输电杆塔为风敏感结构。在设计风荷载下其可靠度指标满足安全要求。但当遭遇强台风时,杆塔抗风性能不足,将发生破坏事故。

The wind-resistant capacity of a slender transmission tower with a small root span is actively investigated in this study.The model of equivalent random wind loads for transmission towers is established.Furthermore,the action of transmission lines on tower is considered by establishing the expression of tensile force of transmission lines.Then,the analytical method of wind-resistant reliability of slender transmission tower with a small root span is proposed.A real transmission line-tower system constructed in southern coastal areas is taken as an example to examine the wind resistant reliability subjected to different strong wind loading.The made observations indicates that the slender transmission tower is a typical wind-sensitive structure.The tower reliability index satisfies the safety requirement under design wind loads.When the tower is attacked by strong typhoons,the tower will destructed due to the lack of wind-resistant capacity.