Abstract
Mining-induced stress redistribution leads to rock deformation, fracture propagation, gas outflow, and floor water inrush, which present significant challenges for the layout of extraction roadways. To optimize the layout in deeply buried coal seams, a stress distribution model for the floor under mining effects was developed based on semi-infinite body theory. This model elucidates the characteristics of floor stress distribution. Simulations were conducted to analyze surrounding rock stress in extraction roadways with various layouts, resulting in a proposed optimized configuration through comparative analysis. The principal findings are as follows: (1) The floor stress model indicates that vertical stress decreases with depth, exhibiting a notable reduction after reaching 5 m below the floor. (2) Numerical results align closely with theoretical patterns; specifically, vertical stress forms an “M” shape within the goaf while peak stresses diminish as depth increases. Maximum decay of vertical stress occurs at approximately 10 m beneath the floor. (3) Vertical stress peaks reach their minimum value of 10.55 MPa when the inner offset coal pillar measures 30 m; similarly, horizontal stress peaks are minimized at 19.37 MPa with an outer offset also set at 30 m. Notably, the failure zone is smallest—approximately 2 m—when employing this outer offset arrangement. (4) The optimized layout positions the extraction roadway at a depth of 17 m below the floor while maintaining a coal pillar with an outer offset of 30 m. (5) Monitoring efforts conducted at a Shanxi coal mine revealed that the failure range extended to only 1.9 m, corroborating theoretical predictions and indicating no significant deformations occurred. This study provides a robust theoretical foundation for determining optimal positioning of extraction roadways within deeply buried coal seams and serves as a valuable reference for analogous mining projects.
Data availability
The datasets generated during and/or analysed during the current study are available from the corresponding author on reasonable request.
References
Huang, Q. S. & Cheng, J. L. Research on stress distribution and failure characteristics of coal mining floor in soft-hard alternant strata [J]. Rock. Soil. Mech. 38 (S1), 36–42 (2017).
Liu, W. T. et al. Calculation method and main factor sensitivity analysis of inclined coal floor damage depth [J]. J. China Coal Soc. 42 (04), 849–859 (2017).
Shao, J., Zhang, Q. & Zhang, W. Evolution of mining-induced Water Inrush Disaster from a Hidden Fault in Coal Seam Floor Based on a Coupled stress–seepage–damage model[J] Vol. 10, 1–21 (Geomechanics and Geophysics for Geo-Energy and Geo-Resources, 2024). 1.
Wang, Y., Huang, J. & Wang, G. Numerical analysis for mining-induced stress and plastic evolution involving influencing factors: high in situ stress, excavation rate and multilayered heterogeneity[J]. Eng. Comput. 39 (8), 2928–2957 (2022).
Kang, H. P. & Gao, F. Q. Evolution of mining-induced stress and strata control in underground coal mines [J]. Chin. J. Rock. Mech. Eng. 43(01), 1–40 (2024).
Lu, J. et al. Three-dimensional Physical Model Experiment of mining-induced Deformation and Failure Characteristics of Roof and Floor in Deep Underground Coal seams[J] Vol. 150, 400–415 (Process Safety and Environmental Protection, 2021).
Ma, B. W. et al. Study on the impact failure and energy release of surrounding rock of roadway under dynamic disturbance [J]. J. Min. Strata Control Eng. 6 (04), 5–22 (2024).
Wang, J. C. et al. Mining-induced stress rotation and its application in Longwall face with large length in Kilometer deep coal mine [J]. J. China Coal Soc. 45 (03), 876–888 (2020).
Wang, H. Z. et al. A comparative study on floor failure law in deep and short-distance coal seam mining [J]. J. Min. Saf. Eng. 37 (03), 553–561 (2020).
Zhao, C. & Song, W. Mechanical models for comparative analysis of failure characteristics and groundwater inrush of coal seam Floors[J]. Appl. Sci. 12 (23), 12164 (2022).
Qian, M. G. On sustainable coalmining in China [J]. J. China Coal Soc. 35(04), 529–534 (2010).
Zhang, C. et al. Research on large deformation mechanism of recovery roadway under mining stress conditions[J]. Heliyon, 10(13). (2024).
Zhang, H. L. et al. Study on failure evolution laws and control technology of roadway surrounding rock under mining circumstances [J]. J. Min. Saf. Eng. 30 (05), 653–658 (2013).
Wang, L. G. et al. Stress distribution and damage law of mining floor [J]. J. Min. Saf. Eng. 30 (03), 317–322 (2013).
Luo, S. H. et al. Evolution characteristics of mining stress of bearing arch and interval strata in Longwall mining of steeply dipping coal seam groups [J]. J. China Coal Soc. 48 (02), 551–562 (2023).
Wang, J. et al. Deformation and failure laws of roadway surrounding rock and support optimization during shallow-buried multi-seam mining[J]. Geomatics Nat. Hazards Risk. 11 (1), 191–211 (2020).
Yang, S. M. Numerical simulation study on reasonable horizon of floor drainage roadway in Yian mine [J]. Saf. Coal Mines. 46 (06), 164–166 (2015).
Zhao, C. et al. Study on stress distribution of floor and gas drainage technology in downward mining of close distance coal seam group [J]. Coal Eng. 51 (07), 109–113 (2019).
Tang, Z. et al. Optimum Analysis of Floor Gas Extraction Roadway Location in Gassy Mine Based on FLAC3D [J] Vol. 42, 88–91 (Mining Safety & Environmental Protection, 2015). 02.
Liu, Z. W. & Zhang, S. Study on rational layout of floor gas drainage gateway in high gassy-outburst seam [J]. Coal Sci. Technol. 46 (10), 155–160 (2018).
Li, Y. E. et al. Surrounding rock’s failure characteristic and rational location of floor gas drainage roadway above deep confined water [J]. J. China Coal Soc. 43 (09), 2491–2500 (2018).
Fan, Z., Song, X., Wang, D., Ayasrah, M. & Li, S. Poroelastic solutions of a Semi-Permeable Bore-hole under Non-Hydrostatic in situ stresses within transversely isotropic Media[J]. Int. J. Geomech. 25, 04024342 (2025).
Gao, R., Kuang, T., Meng, X. & Huo, B. Effects of ground fracturing with horizontal fracture plane on rock breakage characteristics and mine pressure control[J]. Rock. Mech. Rock. Eng. 54, 3229–3243 (2021).
Gao, R. et al. Ground fracturing of multi-strata for strong ground pressure control in extra-thick coal seams with hard roofs: numerical simulation and case study[J]. Eng. Fract. Mech. 303, 110129 (2024).
Zhang, X. & Li, J. Advancements and challenges of high-speed active flow control: plasma actuators[J]. Int. J. Heat Mass Transf., 252, 127481 .
Li, J. & Zhang, X. Active flow control for supersonic aircraft: A novel hybrid synthetic jet actuator[J]. Sens. Actuators A: Phys., 302, 111770 .
Jiang, S., Zhang, J., Diao, K., Liu, X. & Ding, Z. Research advances in solvent extraction of lithium: the potential of ionic Liquids[J]. Adv. Funct. Mater. 35 (29), 2423566 (2025).
Zhang, H. L. & Wang, L. G. Computation of mining induced floor additional stress and its application [J]. J. Min. Saf. Eng. 28 (02), 288–292 (2011).
Funding
This research was funded by the National Key R&D Program of China (No. 2022YFE0129100).
Author information
Authors and Affiliations
Contributions
Conceptualization, X.C. and R.M.; methodology, Y.Z.; software, Y.Z.; validation, Y.Z. and R.M.; formal analysis, Y.X.; investigation, Y.X.; resources, X.C.; data curation, X.C.; writing—original draft preparation, X.C.; writing—review and editing, R.M.; visualization, J.C.; supervision, J.L.; project administration, Y.Z.; funding acquisition, Y.Z. All authors have read and agreed to the published version of the manuscript.
Corresponding authors
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
Open Access This article is licensed under a Creative Commons Attribution-NonCommercial-NoDerivatives 4.0 International License, which permits any non-commercial use, sharing, distribution and reproduction in any medium or format, as long as you give appropriate credit to the original author(s) and the source, provide a link to the Creative Commons licence, and indicate if you modified the licensed material. You do not have permission under this licence to share adapted material derived from this article or parts of it. The images or other third party material in this article are included in the article’s Creative Commons licence, unless indicated otherwise in a credit line to the material. If material is not included in the article’s Creative Commons licence and your intended use is not permitted by statutory regulation or exceeds the permitted use, you will need to obtain permission directly from the copyright holder. To view a copy of this licence, visit http://creativecommons.org/licenses/by-nc-nd/4.0/.
About this article
Cite this article
Chen, X., Ma, R., Zhou, Y. et al. Instability mechanism of deeply buried coal seam floor under mining effects and optimization of extraction roadway layout. Sci Rep (2026). https://doi.org/10.1038/s41598-026-39341-6
Received:
Accepted:
Published:
DOI: https://doi.org/10.1038/s41598-026-39341-6
