Results 181 to 190 of about 13,620,505 (264)

Pilot tests of continuous gas extraction with improved L-shaped wells from mining and goaf areas. [PDF]

Sci Rep
Zhang J, Qin Y, Li G, Ma H, Li G, Li G, Liu T, Li J, Ji C, Guo M.   +9 more
europepmc   +1 more source

Study on Roof‐Control Technology for Gob‐Side Entry Retaining Under Composite Roofs

Energy Science &Engineering, EarlyView.
This study develops a roof‐control technology system for gob‐side entry retaining under composite roofs. By integrating field measurements, theoretical analysis, and numerical simulation, it reveals the spatiotemporal evolution of the plastic zone and proposes a targeted support method, providing theoretical and practical guidance for safe and ...
Dong Li, Yujiang Zhang, Yunlou Du, Haodong Zheng, Baoji Yang   +4 more
wiley   +1 more source

Deviatoric stress evolution and time step control technology of retreat roadway surrounding rock in fully mechanized working face. [PDF]

Sci Rep
Wang Z, Li T, Lin L, An X, Zhao H, Geng X, He J.   +6 more
europepmc   +1 more source

Optimization of Blasting‑Induced Roof Cutting Parameters in Key Stratum and Its Application in Gob‑Side Entry Retention Technology

Energy Science &Engineering, EarlyView.
This study addresses hard roof coal seam conditions by optimizing key stratum blasting‐cutting parameters through theoretical analysis, numerical simulation, and field tests. It proposes calculation methods for blast hole spacing and delay timing based on stress wave theory, controlling roadway deformation within 35 mm, thereby enhancing resource ...
Qiong Liu, Duanxiang Fu, Hongbin Li
wiley   +1 more source

A multi-field coupled model for gas migration in high-temperature coal seams considering fracture zones and fracture roughness. [PDF]

PLoS One
Jiang S, Zhang M.
europepmc   +1 more source

Numerical Simulation Study on Optimization of Horizontal Sublevel Top‐Coal Caving Mining Technique for Steeply Inclined Extra‐Thick Coal Seam

Energy Science &Engineering, EarlyView.
As the sublevel height increases, the top‐coal recovery amount gradually increases, but both the top‐coal recovery rate and the thickened top‐coal recovery rate show a downward trend, and the decline in the top‐coal recovery rate is gradually increasing. The comparison indicates that the optimal sublevel height is 20 m.
Hongsheng Tu, Dingyi Hao, Wenhong Xiao, Fuhao Jiang, Shikun Xu   +4 more
wiley   +1 more source

Deformation characteristics of weakly cemented overburden in Western mining areas in China. [PDF]

Sci Rep
Zhang G, Zhang H, Li G, Chen J, Zhao L, Zhou G.   +5 more
europepmc   +1 more source

Damage Characteristics and Stress Distribution Law of Overburden Rock in Multiple Mining of Close Coal Seams

Energy Science &Engineering, EarlyView.
This study on close coal seams shows that multi‐seam mining increases the height of the fractured zone from approximately 26 m (single upper‐seam mining) to about 49 m. When the lower seam is mined after the extraction of the upper seam, the heights of both the caved zone and the fractured zone increase by approximately two times.
Xiaoyu Wu, Lei Guo, Zedong Sun, Xiaowei Wu, Nan Zhang   +4 more
wiley   +1 more source

Asymmetric deformation law and differentiated control technique for the roadway of an isolated working face in an extra-thick coal seam. [PDF]

Sci Rep
Wu H, Gong P, Zhao T, Bai L, Yan J, Liu A.   +5 more
europepmc   +1 more source

Study on Fluid Pressure in Tubing, Dynamic Stress in Reservoir, and Fracture Propagation Morphology During Variable‐Rate Hydraulic Fracturing

Energy Science &Engineering, EarlyView.
Variable‐rate hydraulic fracturing can induce unsteady flow in the tubing, thereby generating fluctuating fluid pressure near the bottom‐hole reservoir. Dynamic stress is generated in the reservoir under the action of fluctuating fluid pressure and propagates as stress waves.
Zhu Ge, Wang Chaojing, Li Weicheng
wiley   +1 more source