输电杆塔风灾易损性的简化分析

SIMPLIFIED ANALYSIS METHOD FOR ASSESSMENT ON WIND-INDUCED FRAGILITY OF TRANSMISSION TOWER

文中通过具有初始几何缺陷的大变形和弹塑性静态非线性推覆分析,考虑材料强度、弹性模量不确定性,给出了输电塔结构的抗风性能曲线的概率特征;然后基于我国规范等效静风荷载计算理论,给出了随机风效应的极值概率分布特征;最后采用性能水准划分的量化方法,对该塔的轻微、严重和倒塌破坏三个性能水平的易损性曲线进行了评估。研究为输电塔的抗风设计,以及既有电网线路风灾风险的概率评估,提供了理论探索和实用分析方法。

The probability characteristics of wind-resistance performance curve of the tower were gained based on the nonlinear static push-over analysis(NSPA)and large deformation of the initial geometric defects,considering the uncertainty of the Yang's model and strength of the material properties.Then,the extreme value probability distribution characteristics of random wind effects were given by the equivalent static wind load(ESWL)distribution.Finally,the three damage levels:slight,severe and collapse were quantified by energy equivalent method.The study provides theoretical exploration and practical analysis methods for the wind-resistant design of towers and the probability assessment of wind risk of existing power grid lines.