混合式风电塔架的强度折减系数概率谱模型  

Probabilistic Spectral Model of the Strength Reduction Factors for a Hybrid Wind Turbine Tower

作　　者：李红 柯珂 LI Hong;KE Ke(College of Civil Engineering,Hunan University,Changsha 410082,China;School of Civil Engineering,Chongqing University,Chongqing 400045,China)

机构地区：[1]湖南大学土木工程学院,长沙410082 [2]重庆大学土木工程学院,重庆400045

出　　处：《建筑钢结构进展》2023年第9期73-82,共10页Progress in Steel Building Structures

基　　金：国家自然科学基金(52178111);重庆市自然科学基金(CSTB2022NSCQ-MSX0287)。

摘　　要：为提高风电塔架的抗震性能,提出了考虑耗能时序的混合式风电塔架的概念,重点研究了结构抗震设计与评估的关键指标——强度折减系数。利用等效单自由度体系表征具有三线性滞回特征的新型塔架,并基于不同周期和滞回参数组成的变量矩阵,以320条近场地震动作为激励对等效单自由度体系进行了大量非线性动力分析,获取了3 600万个强度折减系数。强度折减系数均值对结构周期及滞回参数敏感,故基于对比研究选取的对数正态分布概率模型,通过多轮非线性回归分析建立了一系列预测方程,从而实现强度折减系数概率谱模型的建立。预测方程所得结果与原数据库之间良好的一致性,验证了所提预测方程能够量化强度折减系数的概率特征,所提概率谱模型可用于对考虑耗能时序的混合式风电塔架进行抗震性能评估。In order to improve the seismic performance of wind turbine towers,the concept of hybrid wind turbine tower considering the energy-dissipation sequences is proposed,and the key index of structural seismic design and evaluation strength reduction factor is studied. An equivalent single-degree-of-freedom(ESDOF) system is used to characterize the novel tower with trilinear hysteresis characteristic. A set of nonlinear dynamic analyses are performed on the ESDOF system based on the variable matrix composed of different period and hysteresis parameters with 320 near-field earthquake motion records as input excitations,and 36 million strength reduction factors are obtained. The mean strength reduction factors are sensitive to the structural period and hysteresis parameters. Therefore,based on the lognormal distribution probability model selected in the comparative study,a series of prediction equations are established through multi-round nonlinear regression analyses,in order to realize the establishment of the probabilistic spectral model of the strength reduction factor. A good agreement between the results from the prediction equations and the original database verified that the proposed prediction equations is able to quantify the probabilistic characteristics of the strength reduction factors. The proposed probabilistic spectral model can be used for the evaluation of the seismic performance of hybrid wind turbine towers employing energy-dissipation sequences.

关 键 词：耗能时序 混合式风电塔架 强度折减系数 滞回特性 概率谱模型 

分 类 号：TU391[建筑科学—结构工程]