###### Abstract  
A numerical simulation method combining the detailed chemical reaction mechanism of methane deflagration with an approximate real tunnel structure was proposed to confirm whether the uneveness of the tunnel wall during a coal mine gas explosion can be ignored. The approximate real tunnel model and smooth wall tunnel model were developed using 3D modeling methods. The propagation and attenuation processes of shock waves in the two tunnel models, as well as the different dynamic responses of the two tunnel walls, were compared and analyzed. Research results show that the non-uniformity of the tunnel wall decreases the shock wave overpressure and propagation velocity. The peak overpressure reduction value of the shock wave reaches 81.91 kPa, and the shock wave overpressure reaches its peak at an extended maximum time of 7.4 ms. The stress distribution on the approximate real tunnel wall is discontinuous, the propagation speed of stress waves in the bend tunnel is slower, and the duration of high load is relatively low. The displacement of the approximate real tunnel after gas explosion is lower than that of tunnels with smooth walls, and the displacement of most measuring points on the tunnel on the right is only 1/3-1/2 that of the smooth tunnel. C 2020 2020 2020 3 March 2020  
spaces, but, at the same time, can also accurately capture the shock wave flow field at every moment. Among them, computational fluid dynamics (CFD) is widely used to accurately simulate the evolution of a shock wave flow field in a confined space following a methane/air premixed gas deflagration. [PERSON] et al. [8] used a flame accelerator simulator (FLACS) to establish a large-scale tunnel model. The effects of methane volume concentration, blockage rate, tunnel length, and cross-sectional area on gas explosion overpressure were studied. [PERSON] et al. [9] studied the variation in shock wave overpressure in the main tunnel under bifurcated tunnels with different lengths and angles using the CFD program. [PERSON] et al. [10] established a numerical model of gas explosion using OpenFOAM open-source CFD code based on the spatial structure characteristics of goat. The flame and shock wave propagation characteristics induced by the gas explosion were analyzed under different arrangements for gradient diameter rocks. [PERSON] et al. [11] explored the influence of cavity structure on explosion wave propagation through theoretical analysis, experimental research, and numerical simulation. A numerical model of shock wave propagation in a cavity was established to study the propagation process of explosion shock waves in cavities of different sizes. These studies have revealed the propagation and attenuation laws of shock waves in different gas explosion scenarios. However, the structural displacement and deformation under the impact load of gas explosion cause energy loss, and changes in the structural plane also alter the direction of shock wave reflection. For situations with structural deformation, analyzing only the explosion flow field lacks accuracy [12; 13]. The Arbitrary Lagrangian-Euler (ALE) algorithm can accurately and efficiently solve the problem of the large deformation of structures caused by explosion [14; 15; 16]. Among its types, empirical methods, such as the TNT equivalent method [17] and equivalent gas explosion pressure method [18; 19], are often used as the explosion sources of gas explosion. [PERSON] et al. [20] simplified the gas explosion load to an equivalent TNT explosive to simulate the scene of accidental explosions in industrial sites. The propagation and interaction of shock waves in complex environments, such as in gas storage, were studied. [PERSON] et al. [21] used improved material constitutive and state equations to characterize gas explosion and reproduced the June 13 gas explosion accident in Shiyan, Hubei Province. The propagation process of shock wave inside buildings and the evolution process of building damage related to the accident were studied.