Study on evolution mechanisms of overburden structure and coordinated support in conditions of thick unconsolidated layers over thin bedrock
Sun Ke1, Zheng Canguang2，Xing Haoshu3, Pan Deyuan4, Zhang Lingzhuo3
1. Ordos Yingpanhao Coal Co., Ltd., Ordos 017399, China; 2. Yankuang Energy Group Co., Ltd., Jining 272000, China;
3. College of Energy and Mining Engineering, Shandong University of Science and Technology, Qingdao 266590, China;
4. Jining No.2 Coal Mine,Yankuang Energy Group Co., Ltd., Jining 272072, China
Aiming at the problem of large deformation and impact instability of surrounding rock in gob-side entry under the condition of deep topsoil-thin bedrock strata in Juye mining area, No.2303 Face of Guotun Coal Mine was taken as the engineering background, and revealed the evolution mechanism of overburden structure of deep topsoil-thin bedrock through theoretical analysis, numerical simulation and field test. The research showed that the bedrock layer cannot formed an effective bearing structure due to its low strength and small thickness, which led to the degradation of the overburden from the traditional ' three zones ' to the two-zone structure of the immediate loading zone ( ILZ ) and the static loading zone ( SLZ ). The surface soil layer migrated in an inverted trapezoidal shape, which induced continuous high static load stress, resulting in the gradual deterioration of the surrounding rock of the roadway, such as roof subsidence, asymmetric convergence of two sides, expansion of shallow fracture zone and deep energy accumulation. Based on this, the collaborative optimization support technology of variable diameter pressure relief was proposed : the drilling design of shallow small aperture + deep large aperture was adopted, and the shallow hole section was backfilled with polymer materials to realize the shallow integrity and deep energy release. The application results showed that the technology could effectively control the deformation of surrounding rock, and provided theoretical basis and technical reference for the surrounding rock control of deep gob-side roadway under similar geological conditions.
孙 轲1，郑灿广2，邢浩树3，潘德远4，张令卓3. 深厚表土薄基岩覆岩结构演化机制及协同支护研究[J]. 煤炭与化工, 2026, 49(1): 16-24，31..
Sun Ke1, Zheng Canguang2，Xing Haoshu3, Pan Deyuan4, Zhang Lingzhuo3. Study on evolution mechanisms of overburden structure and coordinated support in conditions of thick unconsolidated layers over thin bedrock. CCI, 2026, 49(1): 16-24，31..
