Experimental research and application of a new no-pillar green coal mining method

Traditional coal mining methods with pillars have problems such as severe resource wastage, extensive roadway excavation, intensified pressure for mining and development replacement, and ecological damage. To address these issues, a new no-pillar green coal mining method is proposed. This method is explored using the 9101 working face of Xiashanmao Coal Mine as the engineering background. Firstly, the mechanism of this method is revealed through physical model experimental research. The findings of the research indicate that the technique employs directional blasting to disconnect the goaf roof from the roadway roof, segmenting the long cantilever beam above the roadway into shorter segments. Meanwhile, manual control is applied to regulate the height of directional blasting, ensuring the thorough collapse of the goaf roof. The crushing expansion characteristics of gangue are then utilized to fill the goaf, providing support to the roof. The synergistic integration of stress relief and filling collectively contributes to the preservation of the roadway. Furthermore, the new method has achieved good results in surrounding rock stress and deformation control. Subsequently, the accuracy of the model test results is verified through numerical simulation, based on which, an evaluation index is established to select the optimal blasting parameters. Finally, on-site engineering applications are conducted, and monitoring results indicate that the new mining method meets the requirements of surrounding rock control. Simultaneously, it minimizes the need for roadway excavation, mitigates the wastage of coal pillar resources, and attains the objective of safe and environmentally friendly mining practices.