基于有限元网格尺寸效应影响的峰值应变修正研究  

Study on peak strain correction based on the impact of finite element mesh size effect

作　　者：彭容新 陈爱军[1] 贺国京[1] 王解军[1] PENG Rongxin;CHEN Aijun;HE Guojing;WANG Jiejun(School of Civil Engineering,Central South University of Forestry and Technology,Changsha 410004,China)

机构地区：[1]中南林业科技大学土木工程学院,湖南长沙410004

出　　处：《铁道科学与工程学报》2018年第12期3148-3157,共10页Journal of Railway Science and Engineering

基　　金：国家自然科学基金资助项目(51178473);湖南省交通科技计划项目(201526)

摘　　要：对混凝土塑性损伤模型的单轴应力-应变关系、损伤变量、屈服准则和流动法则等进行阐述。利用ABAQUS对标准立方体混凝土试块模型采用不同网格尺寸进行计算,通过回归分析得到网格尺寸与本构模型峰值应变的函数关系。随后建立矩形截面单肢墩与双肢墩的有限元模型,基于上述函数进行损伤模型的峰值应变修正。并根据2个桥墩的有限元模型,设计并进行2个试验墩的试验研究。通过对比可见,调整峰值应变可有效消除网格尺寸对混凝土结构有限元分析的影响,ABAQUS塑性损伤模型在调整峰值应变后计算所得结果与试验结果更接近。且此方法对简单结构更为有效,而对于较为复杂结构,应视具体结构的复杂情况进行详细分析。Firstly,the uniaxial stress-strain relation,damage variable,yield criterion and flow rule of the plastic damage model of concrete were expounded.Then,ABAQUS was used to calculate the standard cubic concrete sample block model with different mesh size,the function relation between the mesh size and the peak strain of the constitutive model was obtained by regression analysis.Then the finite element model of single pier and double pier with rectangular section was established,and the peak strain of damage model was corrected based on the above function.According to the finite element model of two piers,two test piers were designed and studied.By contrast,adjusting peak strain can effectively eliminate the influence of mesh size on the finite element analysis of concrete structure,and the results obtained by ABAQUS plastic damage model in adjusting peak strain are closer to the experimental results.And this method is more effective for simple structure,but for more complex structure,it should be analyzed in detail according to the complexity of concrete structure.

关 键 词：网格尺寸效应 塑性损伤模型 单调加载试验 非线性分析 钢筋混凝土桥墩 

分 类 号：O242.21[理学—计算数学]