跨越高速铁路输电杆塔可靠度分析

RELIABILITY ANALYSIS OF TRANSMISSION TOWER CROSSING HIGH-SPEED RAILWAY

研究了跨越高速铁路输电杆塔可靠度水平,对跨越高铁电力线路安全可靠性进行评价。根据实际工程,采用ABAQUS有限元分析软件,建立了包含两基直线塔、两基耐张塔与三跨输电线的输电塔-线体系三维有限元模型。采用改进的一次二阶矩法(JC法)计算输电杆塔单根杆件可靠指标,利用窄界限法对杆塔体系可靠指标进行分析。综合考虑了0°,45°,60°以及90°风等荷载与覆冰荷载共同作用的影响,基于MATLAB软件编制的计算程序,分别计算了各工况下杆塔的可靠指标。研究结果表明:在设计风速下,考虑覆冰荷载时,呼高48,51 m的杆塔中可靠度水平最低的杆件均位于塔的横担处;呼高48,51 m的输电杆塔的整体可靠指标分别为3. 518与3. 590,稍低于跨越高铁线路输电线路杆塔目标可靠指标3. 7的要求。

To estimate the safety of electricity transmission system crossing high-speed railway,the reliability analysis of transmission towers crossing high-speed railway was carried out.According to practical engineering,a threedimensional finite element model of a transmission tower-line system was established in ABAQUS,which including two linear towers,two resisting-tensile towers and three-span transmission line.The improved first order second moment(FOSM)method and narrow boundary method were selected to calculate the reliability index of transmission tower.Considering the combined action of ice load and wind load at different angles,the reliability indexes were calculated by using the calculator program based on Matlab software.The results showed that the elements with lowest reliability level were located at the crossarm of the tower;the reliability indexes of two transmission towers were 3.518 and 3.590,respectively,which were slightly lower than the requirement of 3.7 for the transmission line crossing high-speed railway.