为了探究偶然冲击荷载作用下大型LNG储罐穹顶的力学行为，选取16×104m3LNG储罐穹顶局部壳体为试验原型，以抗冲击设计依据为参照，通过变换壳体厚度、飞射物质量、冲击速度等参数，进行了15个工况的冲击试验。试验结果表明，偶然冲击荷载作用下，穹顶局部壳体迎弹面将出现成坑破坏，沿径向、环向不产生裂缝；背部钢衬板和混凝土将产生不同类型破坏。弹体能量、侵入姿态、钢筋抗力对混凝土成坑、侵彻深度以及钢衬板的破坏形态影响较大。当飞射物与设计依据动能相同，弹着点位于钢筋间隙内时，局部壳体背部钢衬板不发生破坏，但背部混凝土可形成裂缝或圆形帽状剥落区，设计和安全性评估时应予以关注。基于试验数据拟合出了用于估算事故性偶然冲击荷载作用下大型LNG储罐穹顶破坏情况 的经验公式。

In order to explore the mechanical behavior of dome of a large LNG storage tank under accidental impact loading, the dome local shell of a 16×10⁴m³LNG storage tank was taken as the original model to be tested, the impact resistant design code was used as a reference, impact tests of 15 working conditions were conducted by changing thickness of shell, mass of a flying projectile and its impact velocity. The test results showed that under accidental impact loading, pit damage appears on the dome local shell facing bullet surface, but there is no crack along radial and circumferential directions, the steel plate and concrete at the back have different damage types; projectile body energy, intrusion attitude, and reinforcing bar resistant force have great influences on concrete pit, penetration depth and steel plate failure modes; when the projectile kinetic energy is the same as that of the impact resistant design code and the projectile falls in the gap between reinforcing bars, the steel plat at the dome local shell back is not destroyed, but the concrete at the back has a crack or a circular cap flaking zone, pay attention to this situation during design and safety assessment. Based on the test data, an empirical formula was fitted for estimating the dome failure of a large LNG storage tank under accidental impact load.