西安建筑科技大学学报(自然科学版)

纤维增强复合材料(fiber reinforced polymer,简称FRP)常被用于加固钢筋混凝土结构,FRP与混凝土的粘结性能是确保加固效果的关键,但目前缺乏合适的考虑FRP与混凝土界面行为非线性和滑移速率效应的本构模型.本研究基于LS-DYNA子程序开发平台,进行了本构模型开发,该模型考虑了界面本构非线性关系及滑移速率效应对界面剪切模态断裂能GIIf的影响,完整定义了中低速荷载(滑移速率为10-7 ～ 10-3 m/s)作用下FRP与混凝土界面的动态粘结-滑移关系.采用该模型对FRP与混凝土界面单元受中低速荷载作用的纯剪切模态进行有限元模拟,有限元计算结果表明,该本构模型可以准确反映中低速荷载作用下FRP与混凝土界面的动态粘结-滑移关系.

Fiber reinforced polymer(FRP)can be used to streng then the concrete structure. The bond behaviors between FRP and concrete significantly affect effectiveness of FRP retrofitting. There is a lack of appropriate constitutive model which includes both bond-slip nonlinearity consideration and strain/slip rate effects. In the current study, based on the LS-DYNA subroutine working platform, a material model is developed. The model considered the nonlinearity of the interface constitutive relationships and the effects of strain/slip rate on the shear mode fracture energy GIIf. A dynamic bond-slip relation of FRP-to-concrete interface under middle/low loading rates(10-7～10-3 m/s)can be completely defined with this developed model. The model is further used to simulate FRP-to-concrete interface elements under middle/low speed loading in shear mode tests. Finite element analysis results show that this developed constitutive model can be used for representing the dynamic behavior of FRP-to-concrete interface under middle/low loading rates accurately.

引言
1 FRP-混凝土界面动态粘结-滑移本构关系
2 本构模型子程序开发
3 子程序测试与验证
4 结语

图1 单个Cohesive单元纯剪边界条件<br/>Fig.1 Pure shear constraints of single cohesive element

图1 单个Cohesive单元纯剪边界条件
Fig.1 Pure shear constraints of single cohesive element

图2 子程序计算结果和本构模型对比<br/>Fig.2 Comparison of subroutine calculation results with constitutive model

图2 子程序计算结果和本构模型对比
Fig.2 Comparison of subroutine calculation results with constitutive model

图3 不同滑移率时的计算结果与动态本构模型对比<br/>Fig.3 Comparison of calculation results with dynamic constitutive models at different slip rates

图3 不同滑移率时的计算结果与动态本构模型对比
Fig.3 Comparison of calculation results with dynamic constitutive models at different slip rates

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备注

引言

1 FRP-混凝土界面动态粘结-滑移本构关系

2 本构模型子程序开发

3 子程序测试与验证

4 结语

期刊信息