Experimental investigation on the local damage behavior of reinforced concrete-stainless steel membrane composite material structures subjected to large-scale missile impact

Large-scale membrane liquefied natural gas (LNG) storage tanks may experience missile impacts caused by wind or explosions during operation. However, the damage and dynamic response of reinforced concrete (RC) and stainless steel membrane (SSM) composite structures of the tank under such impacts remain unclear. This study addresses this gap by investigating the damage characteristics and dynamic responses of RC-SSM composite structures through eight large-scale missile impact tests. The findings reveal that the RC plates exhibit penetration, scabbing, and perforation damage. Failures at the interface between the SSM insulation system and the RC component are attributed to reverse tensile stress exerted on the rear surface of the RC plate, coupled with rebar-induced actions, ultimately resulting in detachment of its protective layer. Additionally, indirect effects from concrete conical plugs and scab fragments contribute to damage in the SSM insulation system. The impact loads cause the corrugations and knots of the stainless steel membrane to flatten, effectively absorbing a significant amount of impact energy. This observation suggests that the corrugated membrane exhibits superior impact resistance compared to flat films. To meet the requirements of "airtightness," this study establishes five damage modes and proposes an evaluation methodology for RC-SSM composite structures under large-scale missile impacts.