Objective: This study aims to investigate the non-ideal rupture mechanism of burst discs within an explosion shock tube and its impact on the propagation characteristics of shock waves within the tube. Gaining a comprehensive understanding of the complex dynamics involved in burst disc rupture and its effect on shock-wave propagation is essential for enhancing the safety and reliability of explosion simulation devices, such as explosion shock tubes. These devices are vital tools in explosion damage research. Methods: This study was conducted using a 13-meter-long explosion shock tube under varying explosion intensity conditions. High-speed strain and dynamic pressure acquisition methods were employed to determine the rupture time and pressure peak values corresponding to different burst disc opening ratios. High-speed photography and the Schlieren method were employed to observe the impact of varying opening ratios on downstream shock-wave propagation. A theoretical analysis of shock-wave flows was performed to develop a semi-empirical model that captured the differences in the Mach number within the downstream pipeline for various burst disc opening ratios. Furthermore, the attenuation rate of the incident shock wave was analyzed. By integrating rigid body fixed-axis deflection theory with the Drewry model, a high-precision prediction model was established to accurately determine the burst disc rupture angle under instantaneous explosion loads. Results: The high-speed strain and overpressure measurements reveal that the burst disc rupture process unfolds in three distinct stages: the crack tip formation stage, petal evolution stage, and plastic completion stage. The crack tip formation stage plays a crucial role in affecting the pressure rise rate in the driving section. Meanwhile, the petal evolution and plastic completion stages determine the overpressure peak throughout the rest of the shock tube. Furthermore, a theoretical analysis of shock-wave flows leads to the development of a semi-empirical model describing the Mach number variations in the downstream pipeline corresponding to various burst disc opening ratios. By examining the attenuation rate of the incident shock in the experimental section, the propagation characteristics of shock waves are elucidated, leading to the construction of a quantitative model. The shock-wave attenuation rate transitions through three distinct phases. Initially, it increases gradually as the burst disc's petal evolution stage impedes the flow, affecting both shock-wave generation and propagation. Subsequently, when A_ratio surpasses 0.2, the attenuation rate rises sharply, owing to reduced obstruction from the disc and increased dynamic loads in the driver section, leading to intensified shock-wave decay. Furthermore, once A_ratio exceeds 0.5, the attenuation rate stabilizes, indicating a dynamic equilibrium in shock-wave attenuation, which remains unaffected by further changes in A_ratio. Finally, by integrating rigid body fixed-axis deflection theory with the Drewry model, a high-precision prediction model for the burst disc rupture angle under instantaneous explosion loads is established, considerably reducing the model's prediction error rate from 32.59% to 6.31%. Conclusions: Overall, this study provides a robust experimental and theoretical framework for understanding the flow field evolution within a shock tube influenced by the non-ideal rupture effects of a burst disc. The findings substantially enhance the safety and reliability of explosion simulation devices, such as explosion shock tubes. The findings of this study have the potential to advance the structural design of explosion simulation devices and provide valuable insights into the evolution of flow fields influenced by non-ideal burst disc ruptures.