## 5 Discussion  
First, the discovered \"U-shaped\" pressure distribution pattern (with measurement deviations controlled within 8.88%) strongly aligns with the evolution patterns of vertical stress in goat areas described in earlier studies [32; 33], and this consistency across multiple data sources powerfully validates the reliability of fiber optic monitoring results. Notably, this finding is not only supported by independent studies [34; 35] using different method ologies, but, more importantly, it achieves continuous, high-resolution pressure distribution monitoring through the innovative application of dual BOTDA and [PERSON] monitoring systems, significantly overcoming the limitations of traditional monitoring methods (such as the borehole stress meters used by [PERSON] et al. [36]) with their limited measurement points. Table 2 summarizes the main differences between DOFS-based monitoring and traditional stress monitoring methods in terms of accuracy, data resolution, and practicality. In terms of theoretical advancement, this research builds upon the abutment pressure distribution theoretical model established by [PERSON] et al. [37], achieving real-time validation through fiber optic sensing for the first time, leading to a more comprehensive and profound understanding of goaf pressure distribution. Particularly, compared to [PERSON] and [PERSON]'s [38] static conclusion that peak abutment pressure reaches 4-6 times the original rock stress, the new monitoring system successfully captures the complete stress evolution process. Previous work considered the impact of rock layer deformation and fracture and proposed a multi-scale optical fiber monitoring method. However, this method only obtained the fracture location and range during the rock layer fracture stage. More significantly, by integrating fiber optic sensing with fracture mechanics, this research not only validates [PERSON]'s [39] logarithmic relationship between stress recovery and surface subsidence but also establishes a more direct and precise measurement methodology, effectively addressing the limitations of traditional indirect measurement methods while providing robust experimental support for the theoretical frameworks proposed in earlier studies [40; 41], thereby achieving important breakthroughs in both technological innovation and theoretical development. In order to verify the effectiveness and universality of the proposed fiber-driven goaf stress field inversion method, we further analyzed the BPPS data in Ref. [25]. As shown in Figure 13, the optical fiber strain measurements were recorded at multiple advancing distances of the working face: 124 cm, 164 cm, 192 cm, and 232 cm. These measurements represent the strain data collected after the rock stratum experienced breakage. To determine the goaf pressure, we first calculated the optical fiber displacement under various degrees of deformation using Equations (1) through (10). These displacement values were then input into Equation (16), which establishes an inverse correlation between the key stratum subsidence and goaf pressure, allowing us to derive the goaf pressure through inversion analysis. The results show that the stress distribution data obtained by our inversion are in good agreement with the BPPS measurements. This not only verifies the reliability of our method but also confirms its applicability in other similar conditions. Compared with existing research, the main advantages of this method include establishing a quantitative inversion model from fiber optic monitoring data to goaf pressure; considering the transition process of key stratum from continuous deformation to fracture