Under multi-seam geological conditions, the underlying working face is more prone to frequent and severe roof disasters. Revealing the failure mechanism induced by overlying goafs and residual coal pillars is crucial for ensuring roof stability and safe mining in the underlying seam. Taking the 32302 working face of Chahasu Coal Mine as the research object, this study integrates theoretical analysis, numerical simulation, and field monitoring to systematically investigate the mechanism of abnormal roof weighting. A stress zoning model for the floor under residual pillar influence is established, identifying a shallow shear-compression stress concentration zone and an abnormal stress distribution range of ±50?m. An elastic thin-plate model of periodic weighting is developed, indicating that initial instability occurs after 11.4?m of face advance and becomes significant at 15?m. Based on FLAC3D three-dimensional simulation and field hydraulic support resistance data, the study reveals stress superposition characteristics and transfer paths caused by overlying goaf edges and residual pillars. The peak advance stress increases up to 34.08%, with concentrated stress reaching 24.23?MPa. Accordingly, a three-zone classification criterion based on face advance distance is proposed: a 50?m warning zone ahead of the gate, a ±20?m high-risk zone near the gate, and a 20?m stress-relief zone behind the gate. The results provide theoretical support and engineering guidance for the identification and prevention of roof hazards under similar geological conditions.