Title:
Fracture Mechanism and Control of Surrounding Rock in Gob-Side Entry Retaining with New-Type “Stirrup Constraint Body” for Rapid Support
Author(s):
H. Zhang, X. Cao, Z. Hao, D. Wang, Z. Zhang, H. Zhao, Y. Fan, and J. Wang
Publication:
Structural Journal
Volume:
123
Issue:
5
Appears on pages(s):
227-243
Keywords:
gob-side entry retaining (GER); mechanical model; rapid support; surrounding rock control; surrounding rock fracture mechanism
DOI:
10.14359/51751739
Date:
9/1/2026
Abstract:
Conventional anchor-bolt-confined flexible formwork concrete walls for gob-side entry retaining have clear inherent technical limitations, including incompatible deformation between steel anchors and concrete, low construction efficiency, and grout leakage. However, existing studies have not fundamentally solved the core mechanical problem of confinement efficiency loss caused by deformation mismatch, nor have they established a complete theoretical design framework for new high-compatibility confined systems, which severely limits their application in complex underground conditions. This study develops an innovative prefabricated stirrup-confined flexible formwork concrete system, identifies two primary surrounding rock fracture modes through theoretical analysis, establishes corresponding mechanical models for support design, and verifies the system through laboratory tests and full-scale field trials. The high-strength fiber stirrups achieve tensile strength equivalent to that of deformed steel bars, with an elongation of ≤6%, significantly improving deformation compatibility with concrete. Field results show that the optimized system delivers excellent surrounding rock control, with a maximum roof subsidence of 65 mm, wall displacement of 30 mm, and floor heave of 35 mm. This study provides a validated design framework for high-efficiency confined concrete underground support structures.
Related References:
1. Chen, D.; Wang, X.; Zhang, F.; Li, M.; Zhao, X.; Li, G.; Yu, Y.; Wang, G.; Zhao, J.; and Wang, X., “Research on Directional Controllability of Cracking in Hydraulic Fracturing of Hard Overburden Based on Local Stress Field Intervention,” Energies, V. 15, No. 12, June 2022, Article No. 4252. doi: 10.3390/en15124252
2. Qian, D.; Jiao, H.; Deng, J.; Yang, J.; Jiao, M.; Xian, G.; Yu, C.; Zhu, Y.; Liu, J.; Huang, S.; and Li, B., “Instability Mechanism, Pressure Relief, and Long Anchorage Control Countermeasures for Surrounding Rock of Strong Mining Roadway at Large Mining Height Working Face,” Minerals, V. 13, No. 3, Mar. 2023, Article No. 391.
3. Mohr, S. H., and Evans, G. M., “Forecasting Coal Production Until 2100,” Fuel, V. 88, No. 11, Nov. 2009, pp. 2059-2067. doi: 10.1016/j.fuel.2009.01.032
4. Bai, X.; Ding, H.; Lian, J.; Ma, D.; Yang, X.; Sun, N.; Xue, W.; and Chang, Y., “Coal Production in China: Past, Present, and Future Projections,” International Geology Review, V. 60, No. 5-6, 2018, pp. 535-547. doi: 10.1080/00206814.2017.1301226
5. Chen, D.; Chang, J.; Zou, J.; Tian, C.; Xie, S.; Ni, J.; Guo, F.; Zhang, Z.; Zhao, W.; Yang, X.; and Xing, S., “Mechanisms of Surrounding Rock Failure and Control Measures When Main Roof Fractures Directly Above Gob-Side Entry in Thick Coal Seam,” Applied Sciences, V. 15, No. 8, Apr. 2025, Article No. 4284. doi: 10.3390/app15084284
6. Kong, D.; Pu, S.; Cheng, Z.; Wu, G.; and Liu, Y., “Coordinated Deformation Mechanism of the Top Coal and Filling Body of Gob-Side Entry Retaining in a Fully Mechanized Caving Face,” International Journal of Geomechanics, ASCE, V. 21, No. 4, Apr. 2021, p. 04021030. doi: 10.1061/(ASCE)GM.1943-5622.0001972
7. Zhao, J.; Zhang, X.; Jiang, N.; Yin, L.; and Guo, W., “Porosity Zoning Characteristics of Fault Floor Under Fluid-Solid Coupling,” Bulletin of Engineering Geology and the Environment, V. 79, No. 5, July 2020, pp. 2529-2541. doi: 10.1007/s10064-019-01701-0
8. Wang, Y.; Shang, Y.; Li, G.; He, L.; Lei, X.; Tian, H.; and Jia, T., “Failure Mechanism and Control Technology of Surrounding Rock of Gob-Side Entry Retaining in Gently Inclined Coal Seam: A Case Study,” Mining, Metallurgy & Exploration, V. 42, No. 2, Apr. 2025, pp. 787-811. doi: 10.1007/s42461-025-01183-7
9. Cui, D.; Zhang, Y.; Zhang, S.; Wu, X.; Wang, Q.; Cui, B.; and Zhu, D., “Mechanical Mechanism of Surrounding Rock Failure and Stability Control for Gob-Side Entry Driving Near an Advancing Working Face,” Energy Science & Engineering, V. 13, No. 6, June 2025, pp. 2631-2646. doi: 10.1002/ese3.70057
10. Fu, Q.; Yang, J.; Gao, Y.; Li, C.; Chang, X.; and Wu, X., “Mechanism and Surrounding Rock Control of Gob-Side Entry Formation Passing Through Normal Fault: A Case Study,” Environmental Earth Sciences, V. 82, No. 24, Dec. 2023, Article No. 603.
11. Zhang, S.; Che, C.; Zhao, C.; Du, S.; Liu, Y.; Li, J.; and Yang, S., “Effect of Fly Ash and Steel Fiber Content on Workability and Mechanical Properties of Roadway Side Backfilling Materials in Deep Mine,” Energies, V. 16, No. 3, Feb. 2023, Article No. 1505. doi: 10.3390/en16031505
12. Liu, H.; Zhang, B.; Li, X.; Liu, C.; Wang, C.; Wang, F.; and Chen, D., “Research on Roof Damage Mechanism and Control Technology of Gob-Side Entry Retaining Under Close Distance Gob,” Engineering Failure Analysis, V. 138, Aug. 2022, Article No. 106331. doi: 10.1016/j.engfailanal.2022.106331
13. Tan, Y.; Ma, Q.; Zhao, Z.; Gu, Q.; Fan, D.; Song, S.; and Huang, D., “Cooperative Bearing Behaviors of Roadside Support and Surrounding Rocks Along Gob-Side,” Geomechanics and Engineering, V. 18, No. 4, July 2019, pp. 439-448.
14. Cao, X.; Wang, X.; Zhang, Z.; Zhao, H.; Wang, S.; Cao, X.; and Liu, M., “Surrounding Rock Activity Law and Support Optimization of Double Flexible Formwork Wall Gob-Side Entry Retention in Stratified Mining Coal Seams,” Energy Exploration & Exploitation, V. 41, No. 3, May 2023, pp. 1141-1168. doi: 10.1177/01445987221148876
15. Cao, X.; Wang, S.; Wang, X.; Lei, P.; and Chen, W., “Non-Pillar Mining of Upper Coal Seam Layers with Double-Roadway Driving Using a Flexible-Formwork Pre-Cast Partition Wall,” Measurement Science and Technology, V. 35, No. 10, Oct. 2024, Article No. 105601. doi: 10.1088/1361-6501/ad6027
16. Cao, X.; Wang, X.; Liu, H.; Wang, S.; Wang, D.; and Liu, Z., “Analysing the Application of a Flexible Formwork Pre-Cast Wall Driving Roadway Along Goaf in a Large Mining Height Face,” Scientific Reports, V. 14, No. 1, 2024, Article No. 16335. doi: 10.1038/s41598-024-67211-6
17. Cao, X.; Wang, S.; Wang, X.; Yang, Z.; and Li, A., “Research Analytics on the Applications of Flexible Formwork Gob-Side Entry Retention Technology in Medium-Thickness Coal Seams with Large Inclination Angles,” PLoS One, V. 20, No. 5, 2025, Article No. e0323337. doi: 10.1371/journal.pone.0323337
18. Liu, W. X.; Wang, X. L.; Liu, H. H.; Cao, X. F.; He, B.; Liu, J. F.; Chang, Q.; and Li ,A, “Technology of Flexible Formwork Retaining Wall Driving Roadway Along Gob in Large Mining Height Face,” Journal of Xi’an University of Science and Technology, V. 44, No, 1, 2024, pp. 94-103.
19. Xie, S.; Wang, E.; Chen, D.; Sun, Y.; Cheng, Q.; Ji, C.; Yan, Z.; and Xiao, H., “Failure Analysis and Control Mechanism of Gob-Side Entry Retention with a 1.7-m Flexible Formwork Concrete Wall: A Case Study,” Engineering Failure Analysis, V. 117, Nov. 2020, Article No. 104816. doi: 10.1016/j.engfailanal.2020.104816
20. Huang, W. P.; Gao, Y. F.; Wen, Z. J.; and Gao, L., “Technology of Gob-Side Entry Retaining Using Concrete-Filled Steel Tubular Column as Roadside Supporting,” Journal of China University of Mining and Technology, V. 44, No. 4, 2015, pp. 604-611.
21. Li, J.; Yin, Z. Q.; Li, Y.; and Li, C. M., “Waste Rock Filling in Fully Mechanized Coal Mining for Goaf-Side Entry Retaining in Thin Coal Seam,” Arabian Journal of Geosciences, V. 12, No. 16, Aug. 2019, Article No. 509. doi: 10.1007/s12517-019-4650-3
22. Luan, H.; Jiang, Y.; Lin, H.; and Li, G., “Development of a New Gob-Side Entry-Retaining Approach and Its Application,” Sustainability, V. 10, No. 2, Feb. 2018, Article No. 470. doi: 10.3390/su10020470
23. Liu, Y.; Li, H.-L.; and Lei, P.-B., “Non-Pillar Mining with Double Roadway Driving Supported by Flexible Formwork Concrete,” Coal Engineering, V. 53, No. 12, 2021, pp. 7-12.
24. Zhao, H.; Wang, S.; Zhang, Z.; Cao, X.; Cao, X.; and Cao, Q., “Surrounding Rock Movement of Layered Double Flexible Formwork Wall Retaining Roadway Under Extra Thickness Coal Seam and Support Optimization,” Journal of Mining and Strata Control Engineering, V. 4, No. 5, 2022, Article No. 053524.
25. Zhang, Z. Q.; Zhao, H. L.; Cao, X. Y.; and Cao, X. F, “Design of Small Coal Pillar Reinforcement and Double Flexible-Formwork Wall Support for Retained Entry in Extra Thick Coal Seam,” Coal Engineering, V. 54, No. 6, 2022, pp. 46-51.
26. Wu, Y. Y.; Cao, X. F.; Liu, C. Y.; Qiu, F. Q.; Liu, W. Q.; Zhao, M. Y.; Wang, Q. H.; and Liu, B. G., “Technical Analysis and Application of ‘Concrete Wall-Roof Cutting-Yielding Pressure’ Gob-Side Entry Retaining,” Coal Technology, V. 43, No. 1, 2024, pp. 85-89.
27. Hou, C.-J., and Li, X.-H., “Stability Principle of Large and Small Structure of Surrounding Rock in Gob-Side Entry Retaining in Fully Mechanized Top Coal Caving Face,” Coal Science and Technology, V. 26, 2001, pp. 1-7.