A Study on the Delamination Growth in Composite Laminates Subjected to Low-Velocity Impact

J. Ocean Eng. Technol. 2002;16(6):55-59.

저속 충격을 받는 복합 재료 적층판의 층간 분리 성장에 관한 연구

장창두,송하철,김호경,허기선,정종진

서울대학교 조선해양공학과,서울대학교 조선해양공학과,서울대학교 조선해양공학과,대우조선공업(주),현대중공업(주)

Keywords: Delamination Growth, Composite Laminate, Low-Velocity Impact, Unit Load Method, Virtual Crack Closure Technique

핵심용어: 층간 분리 성장, 복합재료 적층판, 저속 충격 하중, 단위 하중법, 가상 균열 닫힘법

Abstract

Delamination means that cracking occurs on the interface layer between composite laminates. In this paper, to predict the delamination growth in composite laminates subjected to low-velocity impact, the unit load method was introduced, and an eighteen-node 3-D finite element analysis, based on assumed strain mixed formulation, was conducted. Strain energy release rate, necessary to determine the delamination growth, was calculated by using the virtual crack closure technique. The unit load method saves the computation time more than the re-meshing method. The virtual crack closure technique enables the strain energy release rate to be easily calculated, because information of the singular stress field near the crack tip is not required. Hence, the delamination growth in composite laminates that are subjected to low-velocity impact can be efficiently predicted using the above-mentioned methods.