Under the condition of the shallow coal seam, the laws of roof activity after large mining height longwall face mining and prevention measures for large-area roof weighting are problems that need to be solved urgently. In the background of the super large mining height working face in the upper 108 working face of Jinjitan Coal Mine 12-2, the spatial distribution characteristics of the development and change of the mining-induced abutment pressure and the related support design in the 8.2 m super large mining height and fully mechanized mining face were conducted. It reveals the distribution characteristics of the dynamic stress field and internal and external stress fields. The influence range of the abutment pressure of the super high mining height working face was measured on site. The numerical simulation is carried out, the roadway support structure is analyzed, and the improvement measures are proposed. The research results demonstrate that: The influence range of abutment pressure is 234 m, the obvious influence range of the leading pressure is 47–60 m, and the peak position of the influence of the leading pressure is 15–20 m. The 5 m range is the lateral inward stress field of the coal pillar, the 10–15 m range is the outward stress field of the coal pillar, and the 20 m range is the original rock stress field of the coal pillar. Therefore, it is proposed that the reasonable size of the coal pillar for roadway protection is 20–22 m. Adjusting the distance between screw steel and FRP bolts from 1000 mm to 1200 mm, the length of the roof prestressed anchor cable should be appropriately reduced to 5.5–6 m according to the lithology of the roof.

Mining scrapers as an important part of scraper conveyors are highly prone to wear and fatigue failure. A new scraper capable of turning sliding friction into rolling friction was designed to limit wear and reduce failure rate. To determine the safety and reliability of the new scraper, numerical pulling force measurement was conducted on its physical model and finite element analysis was performed on its 3D model based on SolidWorks Simulation. The results were then compared with data of the traditional scraper. Numerical pulling force measurement results indicated impressively lower friction for the new scraper. Stress, strain, and displacement distributions obtained by static stress analysis based on SolidWorks Simulation proved conformance with the strength and deflection standards. Damage percentage and total life nephograms yielded from fatigue analysis indicated no significant life reduction. Numerical pulling force measurement combined with analysis based on SolidWorks Simulation can help reduce the production cost and development cycle. It plays a great role in determining the safety, reliability, and stability of the new scraper.

In China, soft rock roof makes up the majority of coal mine roof, yet it is easy to break due to low strength and poor integrity. As such, it is difficult for the traditional pillar-based roadway protection means and pillarless mining techniques to effectively control the roadway roof. In order to solve the problems with pillarless mining under soft rock roof conditions, using the 1510 working face of Xinyi Coal Mine as an example, a gob-side caving roadway forming (GSCRF) technique for broken immediate roof is developed. This paper discusses the adaptability and feasibility of this technology through theoretical modeling and on-site engineering testing. A roadway rock surrounding control scheme based on “cable + steel beams + yielding prop” is further designed, and field tests and monitoring are carried out. Field tests show that, during GSCRF of the 1510 working face, the maximum subsidence of the roof remains within 200 mm. The convergence of the two sides causes stabilization. The tension on the anchor cables is gradually becoming stable. The monitoring results show that the roadway has a good stress environment and the surrounding rock is effectively controlled. Compared with the traditional pillarless mining mode, this technology has the technical advantages of achieving complete elimination of coal pillars, reduced pressure on the roadway roof, and interference-free mining of the working face. The research outcome can provide useful reference for pillarless mining by GSCRF and a solution for pillarless mining under soft rock roof conditions.