输电线路杆塔构件可靠度校准

Reliability Calibration of Tower Members in Transmission Line

为确定跨越高速铁路输电线路的可靠度水平,分析计算杆塔构件荷载、抗力的统计参数,对按现行规范设计的输电线路杆塔构件的可靠度进行了校准。分析表明,在永久荷载与风荷载组合下,构件轴心受力强度的可靠指标平均约为3.10,构件轴心受压稳定的可靠指标平均约为2.99;在永久荷载与风荷载和覆冰荷载的组合下,构件轴心受力强度的可靠指标平均约为3.35,构件轴心受压稳定的可靠指标平均约为3.20。永久荷载与风荷载组合时我国输电线路杆塔杆件的可靠度水平比建筑钢结构的可靠度略低;永久荷载与风荷载组合及永久荷载、风荷载与覆冰组合时,我国输电线路杆塔杆件的可靠度水平与美国杆塔构件的可靠度水平相近,比加拿大杆塔构件的高。

To set the reliability level of transmission line crossing high speed railway,the statistical parameters of the load and resistance of tower members in transmission line were analyzed and calculated.The reliability of tower members designed based on the current code were calibrated.It is indicated that the reliability indexes for strength of axially loaded members or the stability of axial compression members are 3.10 and 2.99,respectively,in the combination of permanent load and wind load;and are 3.35 and 3.20 respectively,in the combination of permanent load,wind load and ice load.The reliability of tower member in transmission lines in China is somewhat lower than that of building steel structures,in the combination of permanent load and wind load;but it is close to the reliability of tower members in US,and higher than that in Canada,in the combination of permanent load and wind load,or in the combination of permanent load,wind load and ice load.