Skip to main content
Log in

A damage constitutive model for coal under mining stress and adsorption-desorption

  • Research
  • Published:
Mechanics of Time-Dependent Materials Aims and scope Submit manuscript

Abstract

Coal mining can pose safety risks as mining stress and adsorption-desorption damage the coal in front of the working face. To address this, a damage model under the coupled influence of mining stress and adsorption-desorption was proposed by incorporating statistical damage mechanics and the effective stress principle. The method for determining model parameters was provided, and the model was validated through triaxial compression tests on coal containing methane. The model parameters were qualitatively analyzed, and the impact of parameters on the deformation and damage evolution of coal was also examined. The residual strengths of coal determined by previous classical models and the proposed damage model under various confining pressures were compared. The results mainly show that coal containing methane has distinct stages during triaxial compression, including compaction, elastic deformation, yield, strain softening, and residual deformation. The proposed damage model accurately tracks deformation and damage in a coal containing methane at varying confining pressures. An increase in Weibull distribution parameters causes peak stress and damage accumulation to start at a higher strain. Furthermore, a higher correction coefficient of residual strength results in a faster stress drop rate but lower residual strength of coal after peak stress. The proposed damage model accurately predicts the residual strength of coal under various confining pressures.

This is a preview of subscription content, log in via an institution to check access.

Access this article

Price excludes VAT (USA)
Tax calculation will be finalised during checkout.

Instant access to the full article PDF.

Fig. 1
Fig. 2
Fig. 3
Fig. 4
Fig. 5
Fig. 6
Fig. 7
Fig. 8
Fig. 9
Fig. 10
Fig. 11

Similar content being viewed by others

Abbreviations

\(A\) :

Area

\(D\) :

Damage variable

\(E\) :

Elastic modulus of coal (MPa)

\(F\) :

The strength of coal micro-elements

\(I'_{1}\) :

The first stress invariant

\(J'_{2}\) :

The second deviatoric stress invariant

\(K\) :

Bulk modulus of porous soil (MPa)

\(K_{s}\) :

Bulk modulus of skeleton of soil (MPa)

\(Q\) :

Adsorption capacity (\(\text{cm}^{3}\boldsymbol{\cdot}\text{g}^{-1}\))

\(R\) :

The disturbance factor

GSI:

Geological Strength Index

RVE:

Representative Volume Element

\(m_{i}\) :

Dimensionless empirical parameter

\(c\) :

Cohesion (MPa)

\(f\) :

Degradation rate (%)

\(p\) :

Gas pressure (MPa)

\(p_{w}\) :

Pore pressure (MPa)

\(m_{\mathrm{b}}\), \(s\), \(a\) :

H–B model parameter

\(\alpha \), \(k\), \(k_{1}\), \(k'\), \(B\), \(N\) :

Simplified calculation notation

\(w_{e}\), \(w_{p}\) :

Boundary widths of the damaged entity and the damaged pore in the coal RVE

\(\alpha _{b}\) :

Biot coefficient

\(\beta \) :

The material constant

\(\delta \) :

Correction coefficient of residual strength

\(\varepsilon _{1}\) :

Axial strain (%)

\(\varepsilon _{10}\) :

Axial initial strain (%)

\(\varepsilon _{1t}\) :

Deviatoric strain (%)

\(\varepsilon '_{i}\) :

Effective strain (%)

\(\varphi \) :

The internal friction angle (°)

\(\gamma \) :

Damaged pore factor

\(\lambda \) :

Adsorption degradation coefficient of modulus

\(\nu \) :

Poisson’s ratio

\(\sigma _{1}\) :

Axial stress (MPa)

\(\sigma _{1t}\) :

Deviatoric stress (MPa)

\(\sigma _{3}\) :

Confining pressure (MPa)

\(\sigma _{c}\) :

Uniaxial compressive strength (MPa)

\(\sigma _{i}\) :

Macroscopic total stress (MPa)

\(\sigma '_{i}\) :

Effective stress (MPa)

\(\sigma ''_{i}\) :

Microscopic stress (MPa)

0:

Initial state

\(c\) :

Mining stress

\(cx\) :

Coupling of mining stress and adsorption-desorption

\(d\) :

Damaged zone

\(e\) :

Damaged entity

\(m\) :

Matrix

\(p\) :

Damaged pore

\(r\) :

Residual

\(t\) :

Total part of RVE in coal

\(u\) :

Undamaged zone

\(x\) :

Adsorption-desorption

\(i\), \(j\), \(k\) :

Principal stress direction

References

Download references

Funding

This work was supported by the National Natural Science Foundation of China (No. 52004081), the Key Scientific Research Project of Higher Education Institutions of Henan Province (No. 21A440005), the research fund of Henan Key Laboratory for Green and Efficient Mining & Comprehensive Utilization of Mineral Resources (Henan Polytechnic University), the opening project of Henan Key Laboratory of Underground Engineering and Disaster Prevention (Henan Polytechnic University), the Science and Technology Development Fund Project of China Coal Research Institute (No. 2021CX-II-12), the Natural Science Foundation of Henan Polytechnic University (No. B2020-34), the research fund of Jiaozuo Road Traffic and Transportation Engineering and Technology Research Center (No. JRTT2023008). The financial supports are gratefully acknowledged.

Author information

Authors and Affiliations

Authors

Contributions

Tenglong Rong and Keliu Liu contributed to the conception, design and writing of the manuscript; Sheng Zhang revised the manuscript; Yang Zhao participated in the material preparation and data collection; Pengju Liu and Ming Wang plotted the figures.

Corresponding author

Correspondence to Tenglong Rong.

Ethics declarations

Competing interests

The authors declare no competing interests.

Additional information

Publisher’s Note

Springer Nature remains neutral with regard to jurisdictional claims in published maps and institutional affiliations.

Rights and permissions

Springer Nature or its licensor (e.g. a society or other partner) holds exclusive rights to this article under a publishing agreement with the author(s) or other rightsholder(s); author self-archiving of the accepted manuscript version of this article is solely governed by the terms of such publishing agreement and applicable law.

Reprints and permissions

About this article

Check for updates. Verify currency and authenticity via CrossMark

Cite this article

Rong, T., Liu, K., Zhang, S. et al. A damage constitutive model for coal under mining stress and adsorption-desorption. Mech Time-Depend Mater (2023). https://doi.org/10.1007/s11043-023-09627-7

Download citation

  • Received:

  • Accepted:

  • Published:

  • DOI: https://doi.org/10.1007/s11043-023-09627-7

Keywords

Navigation