Results 91 to 100 of about 4,519 (226)
Research and application of pressure relief technology for fracturing thick hard roof in super-high mining face [PDF]
Aiming at the problems of super-large mining space, strong ore pressure and ultra-high coal wall stability control faced by full-mechanized mining face with ultra-large mining height and thick hard roof, this paper takes the 122104 working face of ...
Peng WANG +11 more
core +1 more source
The movements of overburden induced by mining a thick coal seam with a hard roof extend widely. The effects of breakages in the hard strata on the strata behaviors might vary with the overlying strata layers.
Yiwen Lan +3 more
doaj +1 more source
ABSTRACT Post‐tensioned cross‐laminated timber (PT‐CLT) rocking walls offer a compelling seismic system combining self‐centering behavior with energy dissipation. However, progress in their performance assessment and design has been limited by the lack of a comprehensive parametric modeling tool, as exists for steel or reinforced concrete systems. This
Ghasem B. Shargh +3 more
wiley +1 more source
A stress wave propagation model for coal‐rock combinations under in situ stress was established. Taking a coal mine in Huainan, China as the engineering background, isotropic and anisotropic numerical models were constructed. Field engineering practices were carried out to verify the reliability of the conclusions.
Jianyu Zhang +6 more
wiley +1 more source
Study on Roof‐Control Technology for Gob‐Side Entry Retaining Under Composite Roofs
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 +4 more
wiley +1 more source
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
Glazed transpired solar collectors achieve 48–75% efficiency and 11% more seasonal heat than unglazed designs by cutting convective losses, while both offer complementary benefits for ventilation preheating and dynamic wall insulation, with paybacks of 5.5–6.8 years.
Mohammad Fawaier +7 more
wiley +1 more source
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 +4 more
wiley +1 more source
Study on disaster mechanism of thick and hard overhanging roof and top cutting control technology
To address the challenges of significant deformation and high instability risks in the surrounding rock of unsupported roadways beneath a laterally thick and hard overhanging roof, this study focused on the 3810 working face transport roadway in ...
GENG Ming, SUN Jing
doaj +1 more source
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 +4 more
wiley +1 more source

