Gyu-Dong Kim

High-Energy Impact Behaviors of Hybrid Composite Plates Strengthened with 3D-UHMWPE Composites

This study deals with drop-impact effects of new hybrid concrete plates strengthened with an ultrahigh molecular weight polyethylene (UHMWPE). The proposed 3D-UHMWPE results in excellent mechanical properties such as high abrasion resistance, impact strength, and low coefficient of friction. These special properties allow the product to be used in several high-performance applications. In this study, we used two kinds of high-performance materials for the impact reinforcement of a structure made of conventional materials such as a concrete. In particular, the impact mechanism of a fiber-concrete hybrid structure was studied using various parameters. The parametric studies are focused on the various effects of drop-impact on the structural performance. The combined effects of using different fiber-reinforced materials on the impact behavers are also investigated.

Micromechanical damage identification of vibrating laminated composites using bivariate Gaussian function-based genetic algorithms

This study deals with a micromechanical detection of stiffness degradation occurred by the fiber damage in vibrating laminated composite plates. Five unknown parameters are considered to determine the fiber or matrix damage distribution, which is a modified form of the bivariate Gaussian distribution function. The proposed approach is more feasible than the conventional element-based damage detection method from the computational efficiency because it is independent on the number of divided elements. The micromechanical model is embedded in the reconstruction algorithm using the modified Halpin–Tsai formulation. The numerical examples show that the proposed technique is a feasible and practical method, which can prove the location of a damaged region as well as inspect the distribution of deteriorated stiffness of composites for different fiber angles and layup sequences.