随机风荷载下陡峭山区长短腿输电塔多构件可靠度评估  

Multi-component Reliability Analysis of Unequal Leg Transmission Tower in Steep Mountainous Areas Under Random Wind Loads

作　　者：王成 刘翔云 王涛 辜良雨 李正良[4] 韩大刚 WANG Cheng;LIU Xiangyun;WANG Tao;GU Liangyu;LI Zhengliang;HAN Dagang(China Electric Power Engineering Consulting Group Southwest Electric Power Design Institute Co.,Ltd.,Chengdu 610021,China;School of Transportation Science and Engineering,Harbin Institute of Technology,Harbin 150040,China;Chongqing Research Institute of Harbin Institute of Technology,Chongqing 401151,China;School of Civil Engineering,Chongqing University,Chongqing 400045,China)

机构地区：[1]中国电力工程顾问集团西南电力设计院有限公司,成都610021 [2]哈尔滨工业大学交通科学与工程学院,哈尔滨150040 [3]哈尔滨工业大学重庆研究院,重庆401151 [4]重庆大学土木工程学院,重庆400045

出　　处：《建筑钢结构进展》2024年第5期57-65,100,共10页Progress in Steel Building Structures

摘　　要：长短腿输电塔在陡峭山区的输电线路工程中应用广泛,准确评估该结构体系中各个构件的可靠度水平对其维护加固具有重要意义。鉴于此,基于拟蒙特卡罗法开展了随机风荷载作用下陡峭山区中长短腿输电塔多构件可靠度分析。根据《架空输电线路杆塔结构设计技术规程》(DL/T 5486—2020),给出长短腿输电塔不同构件常见的5类失效模式及其功能函数;通过同时考虑材料和风荷载的随机性,采用拟蒙特卡罗法建立长短腿输电塔多构件可靠度分析框架;以某输送电压为500 kV的输电线路中长短腿输电塔为例,进行了多构件可靠度评估,并分析了不同塔腿级差、杆塔呼高以及设计风速对长短腿输电塔可靠指标的影响规律。分析结果表明:长短腿输电塔的所有构件可靠指标均在3.2以上,满足规范要求的Ⅱ级安全水准,短腿主材为长短腿输电塔最薄弱构件,可靠指标相比于长腿主材减小了23.25%,应予以重视;杆塔呼高每增大6 m,长短腿输电塔可靠指标最大下降3.37%,设计风速每增大1 m∙s^(-1),可靠指标最大降低2.83%;塔腿级差每增大3 m,可靠指标最大降低10.48%,建议杆塔设计时应尽量避免出现塔腿级差过大的情况。Unequal leg transmission tower is widely used in transmission line projects in steep mountainous areas.Accurately assessing the reliability level of every component will be significant for the maintenance and strengthening.In this regard,a multi-component reliability analysis of unequal leg transmission towers in steep mountainous areas under random wind loads is carried out based on the Quasi Monte Carlo method in this paper.According to the Technical Specification for the Design of Steel Supporting Structure of Overhead Transmission Lines(DL/T 5486—2020),five types of failure modes and functional functions of different components of unequal leg transmission tower are given.Considering the randomness of material and wind loads,the Quasi Monte Carlo method is used to establish a multi-component reliability analysis framework of unequal leg transmission tower.A unequal leg transmission tower in a 500 kV transmission line is used as an example for multi-component reliability assessment,and the influence law of different tower leg height difference,nominal height and design wind speed on the reliability index of unequal leg transmission towers is analyzed.The analysis results show that:the reliability index of all components of the unequal leg transmission towers are above 3.2,meeting the code requirements of the second safety level.It should be noted that the short-legged main material is the weakest component of the unequal leg transmission tower,and the reliability index is reduced by 23.25%compared to that of the long-legged main material.For every 6 m increase in tower nominal height,the maximum decrease in reliability index of unequal leg transmission towers is 3.37%.For every 1 m∙s^(-1) increase in design wind speed,the maximum reduction in reliability index is 2.83%.The reliability index is reduced by 10.48% for every 3 m increase in tower leg height difference.It is recommended that the tower design should try to avoid too large leg height difference.

关 键 词：长短腿输电塔 多构件可靠度 拟蒙特卡罗方法 随机风荷载 

分 类 号：TU311.3[建筑科学—结构工程]