燃气爆炸荷载下隧道砌体损伤规律与事故影响范围研究

Research on damage law of tunnel masonry and influence range of accident under gas explosion load

为降低隧道内燃气爆炸时砖砌体抛射物造成人员伤亡的概率,以中缅油气管道隧道砖砌体为研究对象,建立3种不同类型砖砌体的数值模型,将燃气爆炸荷载简化为三角形荷载,基于LS-DYNA软件,研究燃气爆炸荷载下隧道砖砌体结构的损伤规律与砖砌体抛射物的潜在影响范围。研究结果表明:砖砌体在天然气爆炸荷载作用下,可能会发生整体破坏,产生较多抛射物,其中,第1类砖砌体抗爆性能最差,产生的抛射物速度最大,第2,3类砖砌体的抗爆性能相近;随着峰值压力的增大,砖砌体产生的抛射物尺寸更小,数量更多,最大抛射速度与超压峰值近似呈线性关系。研究结果可为隧道燃气爆炸事故划定合理警戒区域,为制定事故纾困措施提供参考依据。

In order to reduce the probability of casualties caused by brick masonry projectiles during the gas explosion in tunnel,taking the brick masonry in the tunnel of China-Myanmar oil and gas pipeline as the research object,the numerical models of three different types of brick masonry were established.The gas explosion load was simplified as triangular load,and the damage law of tunnel brick masonry structure and the potential influence range of brick masonry projectiles under three gas explosion loads were studied based on LS-DYNA software.The results showed that under the natural gas explosion load,the brick masonry might be destroyed as a whole and produce many projectiles.Among them,the first type of brick masonry had the worst anti-explosion performance and produced the largest projectile velocity.The second and third types of brick masonry had similar anti-explosion performance.With the increase of peak pressure,the projectiles of brick masonry were smaller in size and larger in number,and the maximum projectile velocity was approximately linear with the peak overpressure.It can delimit a reasonable warning area for the gas explosion accidents in tunnel,and provide reference for the formulation of accident relief measures.