基于倒塌延性的输电塔地震抗倒塌设计方法

Study on Seismic Collapse Resistant Design Method of Transmission Tower Based on Collapse Ductility

调整结构抗侧刚度是提高地震下结构抗倒塌能力的常用方法,目前该方法多应用于建筑结构,而没有关于输电塔的抗倒塌研究。针对此问题,首先,依托实际输电线路工程,基于ABAQUS软件建立了输电塔有限元模型,采用静力推覆分析(Pushover)和增量动力分析(incremental dynamic analysis,简称IDA)方法,获得了输电塔倒塌延性;其次,针对输电塔薄弱节间,提出了一种以杆件内外径之比为影响参数的输电塔地震抗倒塌优化设计方法;最后,通过有限元分析对优化效果进行了验证。结果表明,该优化方法能有效提高输电塔抗倒塌性能,优化后的输电塔薄弱节间抗震性能最高可达70%,非薄弱节间优化效果在10%左右,可为输电塔抗震设计提供指导。

It is a common method to improve the collapse resistance of structures under earthquakes by carrying out the collapse ductility analysis and proposing an optimization scheme to adjust the lateral stiffness of structures.At present,this method is mostly applied for building structures,and the research on the collapse resistance of transmission towers has not been carried out.Therefore,based on the actual transmission line project,this paper establishes the finite element model of transmission tower based on ABAQUS software to obtain the collapse ductility of transmission tower by using Pushover analysis and incremental dynamic analysis(IDA)methods.For the weak sections of the transmission tower,an optimization design method for seismic collapse resistance of the transmission tower with the ratio of inner and outer diameters of the members as the influencing parameter is proposed,and the optimization effect is verified by finite element analysis.The results show that the seismic performance of the weak section of the optimized transmission tower can reach 70%.Moreover,the optimization effect of the non-weak section is about 10%,which verifies that the optimization method can effectively improve the collapse resistance of the transmission tower and provide guidance for the seismic design of the transmission tower.