用户名: 密码: 验证码:
Modeling of progressive damage for composites under ballistic impact
详细信息    查看全文
文摘
A constitutive model based on the concept of continuum damage mechanics has been proposed to study the progressive damage behavior of composite laminates under ballistic impact. The proposed model is investigated in five steps: First, the quadratic form of damage initiation criteria are presented to predict the initiation of failure in different modes. Second, an exponential form damage evolution law combined with characteristic length based fracture energy approach has been presented. Stiffness degradation is characterized by a variable determined by the equivalent displacement for each failure mode. Third, an experimentally verified strain rate model that considers the rate dependency of the strength and modulus of the composite laminate is considered. Fourth, cohesive elements are inserted at every inter-layer for modeling the delamination evolution. Fifth, the constitutive model has been combined with an element erosion algorithm for the removal of highly distorted elements. Simulations have been performed using reduced integration hexahedra elements (RIHE) and full integration hexahedra elements (FIHE). Implementation of cohesive elements exhibited better delamination progression. Experimentally verified strain rate model enhanced the efficiency of the model showing good correlation between the present simulations and experimental observations, in terms of damage patterns, residual velocity, kinetic energy and ballistic limit.

© 2004-2018 中国地质图书馆版权所有 京ICP备05064691号 京公网安备11010802017129号

地址:北京市海淀区学院路29号 邮编:100083

电话:办公室:(+86 10)66554848;文献借阅、咨询服务、科技查新:66554700