Research on material equivalent method based on damage mode of underwater explosion grillage structure

The rapid prediction of damage to ship plate-frame structures suffering from strong impact loading represents a critical element of research into ship impact damage assessment and protection. The study is concerned with the equivalence and prediction of damage to ship plate-frame structures subjected to underwater explosion loads. The initial investigation focuses on the plastic damage modes of plate-frame structures subjected to impact loading. Subsequently, the compensation model method from dimensional analysis is employed to derive a material equivalence approach based on these plastic damage modes. By integrating experimental and numerical techniques, the study initially establishes material performance parameters for TC4 titanium alloy and LY12 aluminum alloy through testing. Subsequently, the study designs and performs model experiments on the underwater explosion-induced damage to ship plate-frame structures based on the material equivalence approach. A comparative analysis of damage characteristics for plate-frame structures with different materials, as designed using the equivalence method, demonstrates the validity and accuracy of the approach. The findings indicate that the plastic damage equivalence method, developed using the compensation model and grounded in the plastic damage modes of plate-frame structures, effectively represents the damage characteristics across various materials, thereby offering new perspectives for research on ship plate-frame structural damage.