Synergistic Stability Control of Gob-Side Roadways with Small Coal Pillars: Theory and Field Practice

To address the instability of small coal pillars in gob-side entry driving under thick and hard roof conditions, this study proposes a synergistic control technology combining “pressure relief, bundle control, and strong support”. First, a segmented deflection curve model of the coal pillar was established to quantify the correlation between pillar deformation and dominant controlling factors. Numerical simulations (FLAC3D) were then performed to optimize the roof cutting parameters, determining an optimal cutting height of 23.2 m and a cutting angle of 9°. Based on these findings, a comprehensive control scheme was implemented in the Fucun Coal Mine. Field monitoring results indicate that the proposed technology effectively controlled the lateral displacement of the coal pillar to 264 mm and maintained the stability of the roadway. This study provides a theoretical basis and practical reference for deformation control in similar geological conditions.