College of Safety Science and Engineering, Liaoning Technical University, Huludao, Liaoning, China.
Centre for Built Infrastructure Research, School of Civil and Environmental Engineering, University of Technology, Sydney, NSW, Australia.
PLoS One. 2021 Dec 2;16(12):e0260655. doi: 10.1371/journal.pone.0260655. eCollection 2021.
Timber linings are applied as primary supports in the tunnel fault and fracture zones of mines. These linings are essential to prevent broken rock from falling during the occurrence of exogenous fires. In this study, experiments and numerical simulations were carried out using a fire dynamics simulator to investigate the flame-spread rate, flame characteristics, smoke movement, and spread process of timber-lining fires under different wind speeds of 0, 0.25, 0.5, and 0.75 m/s. It was found that cross-section flame spreading follows the three-stage sidewall-ceiling-sidewall pattern. Moreover, the average flame-spread rate increases along the vertical flame-spreading direction and decreases when the flame reaches the timber-lining corners. Moreover, the flame lengths underneath the timber-lining ceiling in the x-direction are longer than those in the y-direction. As the wind speed increases, the normalized flame lengths R(f) in the two directions decrease, and the maximum temperature underneath the ceiling decreases. In addition, the maximum temperature in the three tunnel sections of interest is first recorded in the tunnel cross-section in the initial fire stage. Higher wind speeds correspond to farther distances of the maximum-temperature points of the three timber-lining sections from the fire source.
木质衬里作为主要支撑物应用于矿山隧道断层和断裂带。这些衬里对于防止外部火灾发生时岩石破碎掉落是必不可少的。本研究采用火灾动力学模拟器进行实验和数值模拟，研究了在风速分别为 0、0.25、0.5 和 0.75 m/s 时不同风速下木质衬里火灾的火焰传播速度、火焰特性、烟雾运动和传播过程。结果表明，横截面火焰传播遵循侧壁-天花板-侧壁的三阶段模式。此外，平均火焰传播速度沿垂直火焰传播方向增加，当火焰到达木质衬里角落时则减小。此外，木质衬里天花板下方 x 方向的火焰长度比 y 方向长。随着风速的增加，两个方向的归一化火焰长度 R(f)减小，天花板下方的最大温度降低。此外，在初始火灾阶段，三个感兴趣的隧道段中，最大温度首先记录在隧道横截面上。较高的风速对应于三个木质衬里段的最大温度点距离火源的距离更远。
