Impact Dynamic Response of Spherical Net Shells: Finite Element-Based Computational Analysis Investigating the Influence of Dynamic Constitutive Models

The net shell is a widely utilized large-span space structure known for its aesthetically pleasing design and uniform load distribution, as well as serving as a prominent architectural landmark. In recent years, the impact resistance research of mesh and shell structures has garnered increased attention due to the accumulation of local conflicts. In this study, a parametric model of the spherical mesh shell was developed with Rhino software, and a numerical analysis model for a K8 mesh shell was established through the application of the ABAQUS finite element analysis software. Subsequently, the proposed numerical analysis method for the impact test was applied to validate its accuracy. The research also explored various dynamic constitutive models, such as Cowper-Symonds, Johnson-Cook, modified temperature term Johnson-Cook, and modified strain term and temperature term Johnson-Cook, with the assessment of their impact on the numerical simulation of impact resistance. Based on the impact dynamic response of the spherical net shell of different materials, the selection of an appropriate dynamic constitutive model for the numerical simulation of impact resistance in the spherical net shell was the MJ-C model. The comparative analysis of different materials, including Q235B, Q355B, Q460D, and 6061-T6, indicated that when the impact material failed to penetrate the structure instantly, the improvement of the material strength would enhance the impact resistance of the structure. On the other hand, when the impact material managed to penetrate the structure instantly, the material strength would not significantly help mitigate the damage. Notably, brittle materials, such as aluminum alloy, exhibited a distinct absence of a pronounced yield stage compared with low-carbon steel, which ultimately led to a relatively abrupt deformation.