FRP约束普通和高强混凝土柱轴压性能的有限元分析

现有的大多数纤维复合材料(FRP)约束混凝土轴压本构模型只适用于普通强度的混凝土,对高强混凝土的适用性还有待研究。基于ABAQUS和OpenSees模型,采用有限元方法研究FRP约束混凝土的轴压性能。其中ABAQUS模型采用全尺寸模型和薄片模型两种形式,并采用混凝土破坏塑性模型(CDPM)来模拟被约束的混凝土,通过修改混凝土的压缩硬化曲线来考虑FRP提供的围压。OpenSees模型则通过动态链接库文件引入5个不同的分析型FRP约束混凝土轴压本构模型。最终与相关实验结果进行对比,并相互对比各个有限元模型可以发现,ABAQUS中的薄片模型能最好地模拟FRP约束普通和高强混凝土的轴压性能。

Finite Element Analysis on the Axial Compression Behaviors of FRP-Confined Normal-Strength and High-Strength Concrete Columns

Existing compressive constitutive models for fiber reinforced polymers/plastics (FRP) confined concrete are suitable for normal-strength concrete only. The applicability on FRP-confined high-strength concrete is still questionable. The compression behaviors of FRP-confined concrete were investigated numerically by using finite element method on the platforms of both ABAQUS and OpenSees. The ABAQUS models included a full-scale model and a slice model. In both of these models, the widely-used concrete damaged plasticity model (CDPM) was adopted to simulate the material of concrete. A modified compression hardening curve was proposed to account for the confining pressure from the surrounding FRP. The modified model was found to be suitable to predict the performance of FRP-confined concrete under axial compression. The OpenSees models were several analysis-oriented models for FRP-confined concrete introduced from the dynamic-link-library files. These models'' results were compared with those by experiments. Finally, the finite element models were compared with each other and the vertical slice model in ABAQUS was found to be of the best performance in predicting the compressive behaviors of both FRP-confined normal-strength concrete and high-strength concrete.