Of these methods, a high gas-drainage roadway offers several advantages, such as large extraction flow, long service life, and minimal interference with production, and has gradually become an important measure used for gas control in high-gas mines [10]. However, determining the optimal location for the high gas-drainage roadway is both a critical and challenging aspect of drainage technology [11]. It must be positioned in gas-enriched zones with well-developed fractures to maximize extraction efficiency. Therefore, understanding the evolution of overlying strata fractures is of great significance for achieving efficient gas drainage through a high gas-drainage roadway [12; 13; 14]. Therefore, scholars have proposed several models of overlying strata fractures--such as 'O'-shaped rings [15], high-level annular fracture structures [16], elliptical throwing belts [17], and mining-induced rounded rectangular terrace belts [18]--as well as methods for determining the development height of the overlying strata fractures [19; 20; 21], which laid the theoretical foundations for gas drainage using high gas-drainage roadways. In recent years, gob-side entry retaining has been widely adopted due to its ability to significantly improve the recovery rate of coal resources [22; 23; 24]. However, this practice also presents new challenges to the theories and technologies of gas drainage, particularly for high gas-drainage roadways. Gob-side entry retaining typically employs roof-cutting and pressure-relief techniques to control surrounding rock deformation, and these techniques dramatically alter the overlying strata structure above the goal, thereby significantly influencing the migration and accumulation characteristics of gas [25; 26; 27]. However, in practical applications of gob-side entry retaining with roof cutting and pressure relief in high-gas mines, gas from the goat has been observed to leak into the tailgate roadway, leading to gas over-limit incidents in that area [28]. To address this issue, gob-side entry retaining with roadside filling has been widely adopted in high-gas mines [29; 30]. Owing to the distinct mechanical properties between the roadside filling material and raw coal rock [31; 32; 33], their influence on the evolution of overlying strata fractures also differs from that of traditional roof cutting and pressure relief methods. These differences inevitably result in variations in overlying strata fracture development in the goat, thereby altering the optimal layout of high gas-drainage roadways. However, previous studies have primarily focused on the accurate identification of gas-enriched zones and the optimization of borehole drainage layouts under gob-side entry retaining with roof cutting, as well as the patterns of air leakage from the goat to the tailgate and corresponding control technologies under roadside filling conditions. In contrast, limited attention has been paid to the fracture development patterns of the overlying strata and the optimal layout of high gas-drainage roadways under gob-side entry retaining with roadside filling. In this study, the 91-105 working face of Wangzhuang Coal Mine--featuring a gob-side entry retaining system with a \"pier column + flexible formwork\" roadside filling structure--was selected as the engineering case study. A comprehensive method combining theoretical analysis, numerical simulation, and field testing was adopted to investigate the failure behavior and fracture development characteristics of the overlying strata in both strike and dip directions under the support of the filling structure. Based on these findings, the optimal layout of the high gas-drainage roadway was determined. This study provides a theoretical foundation for gas drainage under gob-side entry retaining with roadside filling and offers practical guidance for gas control in working faces with similar geological and engineering conditions.