架空输电铁塔动力风响应的数值模拟

Numerical Simulation of Along-wind Response of Transmission Tower

运用有限元数值方法分析了两跨三基架空输电线路的顺风向动力响应 .中间铁塔由空间梁单元进行模拟 ,两端的铁塔通过动力等效简化为梁模型 .假设悬垂架空线节点具有空间三个方向平移特征 ,并引入了几何非线性的影响 .在考虑各节点风力空间相关的条件下 ,利用Karman风速功率谱对节点风力进行了数值模拟 .研究表明 ,在分析架空输电铁塔风载条件下的动力响应时 ,应该考虑架空线的动力响应特性的影响 .

A finite element method is applied to the study of along-wind dynamic response of transmission line of two spans with three towers.The central tower is modeled as an assembly of beam elements with six degrees of freedom at each node.The sagged wire is assumed to be composed of straight element with three translational degrees of freedom at each node and the geometric non-linearity is included in the study.The time history of fluctuating wind speed is generated by the multi-dimensional auto-regression method according to power spectrum and spatial correlations.The result has shown that it is necessary to consider the dynamic characteristics of wire when the dynamic response of transmission tower is analyzed.The procedure presented here provides an effective method to check the safety and reliability of the transmission tower.