一种适用于变轴力柱混合试验的改进BWBN模型及其参数识别  

An improved BWBN model for column hybrid test with variation of axial force and its parameter identification

作　　者：郭玉荣[1,2] 潘洪军 GUO Yurong;PAN Hongjun(College of Civil Engineering,Hunan University,Changsha 410082,China;Key Laboratory of Building Safety and Energy Efficiency,Changsha 410082,China)

机构地区：[1]湖南大学土木工程学院,湖南长沙410082 [2]建筑安全与节能教育部重点实验室,湖南长沙410082

出　　处：《铁道科学与工程学报》2021年第11期2988-2997,共10页Journal of Railway Science and Engineering

基　　金：国家自然科学基金资助项目(51878259,51161120360)。

摘　　要：原始的BWBN模型无法很好地描述钢筋混凝土(RC)柱在水平和竖向双向地震作用下的刚度、强度退化以及正负向滞回不对称现象,为了描述这些现象,对原始BWBN模型进行修正。结合16根定轴力柱子的滞回数据,利用改进Park-Ang损伤模型计算柱子强度退化、刚度退化与累计损伤的关系,并相应地对原始模型相关项进行了修正。此外,对变轴力柱用轴力分级插值以及正负向单独计算损伤的方式来考虑变轴力的影响。最后,利用定轴力、变轴力试验数据以及OpenSees的模拟数据对模型有效性进行验证,并计算模型识别数据与试验数据的Pearson相关系数,结果均为强相关,说明模型适用性良好。改进的变轴力BWBN模型能较好地考虑轴力变化对柱子侧向滞回性能的影响,这对于拓宽混合试验应用范围以及实现变轴力柱混合试验有一定意义。同时,本文的研究方法,对未来变轴力恢复模型的研究也有一定参考价值。The original BWBN model cannot describe the stiffness,strength degradation and hysteresis asymmetry of reinforced concrete(RC)columns under horizontal and vertical earthquakes well.To describe these phenomena,the original BWBN model was modified.Combined with the hysteretic data of 16 fixed axial force columns,this paper used the improved Park-Ang damage model to calculate the relationship between the strength degradation,stiffness degradation and cumulative damage of the columns.The related formulas of the original model were revised.In addition,the variable axial force column used the axial force hierarchical interpolation and calculating the damage separately in the positive and negative directions to consider the influence of the variable axial force.Finally,the effectiveness of the model was verified with test data under fixed axial force and variable axial force and simulation data calculated by OpenSees.The Pearson correlation coefficient of model identification data and test data was calculated.The results are all strongly correlated,indicating that the model has good applicability.The improved BWBN model can describe the influence of variable axial force on the lateral hysteresis behavior of columns better,which has an important significance for broadening the application range of the hybrid test and conducting the hybrid test with variation of axial forces.The research method of this paper also has reference significance for the future research of variable axial force recovery model.

关 键 词：RC柱 变轴力 混合试验 改进BWBN模型 参数识别 

分 类 号：TU375.3[建筑科学—结构工程]