On Dynamic Constitutive Model of Granite Under Impact Loading: Effect of Damage on Dynamic Strength

5th International Conference on Environmental Science and Civil Engineering

生态环境科学;土木建筑工程

Liang, Shufeng^1 ; Ling, Tianlong^1 ; Liu, Dianshu^1 ; Li, Shenglin^1

School of Mechanics and Civil Engineering, China University of Mining and Technology (Beijing), Beijing

100083, China^1

关键词: Constant strain rate;    Damage evaluation;    Dynamic constitutive model;    Dynamic mechanical property;    High frequency HF;    SHPB;    Split Hopkinson pressure bars;    Viscoelastic elements;   

Others  :  https://iopscience.iop.org/article/10.1088/1755-1315/283/1/012019/pdf
DOI  :  10.1088/1755-1315/283/1/012019

来源: IOP

【 摘 要 】

Dynamic mechanical properties of granite were tested by a split Hopkinson pressure bar system at constant strain rates. The experimental results show that granite behaves linearly elastic at the initial loading stage, followed by a significant plastic deformation after yielding, and yield strength, ultimate strength and elastic modulus are all rate dependent. On this basis, the simplified Zhu-Wang-Tang (ZWT) constitutive model is applied in this paper, assuming elastic and high frequency viscoelastic elements only. The damage evaluation equation is introduced to the simplified ZWT model to investigate the effect of damage on the dynamic strength of granite due to impact load. Finally, the proposed model is applied to fit the experimental data. It is known that the fitted stress-strain curves at different strain rates are in agreement with the experimental ones. Compared with experimental data, the error of yield stress, peak stress and corresponding strain obtained by fitting method are all not larger than 10%. This demonstrates that the proposed dynamic constitutive model can accurately describe the dynamic mechanical properties of granite under impact loading.