A fractional non-linear creep model for coal considering damage effect and experimental validation

作者：Kang, Jianhong^*; Zhou, Fubao; Liu, Chun; Liu, Yingke

来源：International Journal of Non-Linear Mechanics, 2015, 76: 20-28.

DOI：10.1016/j.ijnonlinmec.2015.05.004

• Fractional derivative
• Visco-elastic-plastic behavior
• Accelerating creep deformation
• Damage effect
• Coal

Accurate prediction of coals creep behavior is of great significance to coalbed methane extraction. In this study, taking into account the visco-elastic-plastic characteristics and the damage effect, a fractional non-linear model is proposed to describe the creep behavior of coal. The constitutive and creep equations of the proposed fractional non-linear model are derived via the Boltzmann superposition principle and discrete inverse Laplace transform. Furthermore, uniaxial creep tests under different axial stress conditions were carried out to validate the proposed model. It is found that the present model can describe the experimental data from creep tests with better accuracy than classical models. Particularly, the present model can predict the accelerating creep deformation of coal which classical models fail to reproduce. Finally, the parametric sensitivity analysis is performed to investigate the effects of model parameters on the creep strain. It is verified that the introduction of fractional parameters and damage factor in the present model is essential to accurate prediction of the full creep stage of coal.

• 出版日期2015-11
• 单位中国矿业大学（北京）