摘要
以基于结构性能的抗震设计理念为应用背景,对风电塔架的抗震性能评估方法进行研究。首先建立目标结构的有限元分析模型,按照设定准则,取前N阶振型,按振型加载的方式进行Pushover加载,获得相应的等效单自由度体系ESDOF(equivalent-single-degree-of-freedom)的能力曲线。然后对原结构多自由度体系和不同的ESDOF体系分别进行弹塑性时程分析。最后将Pushover分析方法和增量动力分析法(IDA)结合起来,尝试用多个等效单自由度体系恢复力模型近似代替原结构进行IDA分析,从而对目标结构进行抗震性能评估。以一个30 m高的预应力风电塔架为例,验证了方法的可行性。本方法结合了多振型组合的Pushover分析方法与能量IDA方法,实现了对风电塔架可靠有效、计算成本较低的抗震性能评估,对未来大型复杂的风电塔架结构抗震分析和性能评估有一定的参考意义。
This paper presents the work on developing a seismic performance evaluation method of wind turbine tower for its performance based design. At first, a finite element model is established. Based on this model, the structure is loaded on by selecting the first several mode shapes according to the designed principle to obtain the corresponding capacity curve of ESDOF （ equivalent-single-degree-of-freedom ） system. After that, elasto-plastic time history analysis is performed on the MDOF （multiple degrees-of-freedom） system of the original structure and ESDOF system, respectively. At last, the pushover analysis and incremental dynamic analysis （IDA） are combined to replace the IDA analysis of the original structure by analyzing the restoring force model of several ESDOF systems for the purpose of seismic performance evaluation of an objective structure. A prestressed concrete wind turbine tower with a height of 30 meters is used to illustrate the proposed method. This method can make use of both multi-mode combination pushover analysis and energy IDA method to evaluate the seismic performance of wind turbine towers, providing reference for the future seismic analysis and condition assessment of large and complex wind turbine towers.
出处
《结构工程师》
北大核心
2017年第1期70-78,共9页
Structural Engineers
基金
上海市浦江人才计划项目(15PJ1408600)
国家自然科学基金资助项目(51508407)
国家自然科学基金资助项目(51508413)
关键词
风电塔架
PUSHOVER分析
弹塑性时程分析
抗震性能评估
IDA分析
wind turbine tower, pushover analysis, elastic-plastic time history analysis, seismic performance evaluation, IDA analysis
