Analysis of crush-damaged carbon-fiber-reinforced-polymer (CFRP) composites with optimization-assisted post-peak-stress modeling

Abstract

In the presented effort, layered CFRP composites samples with differing thicknesses and cross-sections are manufactured and crushed under quasi-static loading conditions. Simulation of the crushes are conducted using traditional continuum mechanics damage models. Parameters are proposed to represent the post peak-stress material behavior including the residual strengths of the fiber and matrix, as well the ultimate strain for deletion of composite elements. This paper presents a systematic approach to identify optimal values for these post peak-stress parameters based on a methodology incorporating CAE models and numerical optimization. An adaptive meta-model based global optimization strategy, with the objective of matching the force-time characteristics of multiple crush experiments simultaneously, has been established to quantify the values of the CFRP’s post peak-stress degradation and erosion material model parameters through calibration. Using two separate test configurations for optimization, a set of values for those parameters are determined. This parameter set is shown to successfully predict the response of additional test cases, including matching of force-displacement curves and crushing modes. The resulting composite crush simulations show a good quantitative as well as qualitative agreement between simulations and experiments to a degree that is difficult to be achieved solely with previous engineering practice.

Implementing deformation, damage, and failure in an orthotropic plastic material model

“…While avoiding an ad hoc parameter tuning exercise, rational procedures can be developed for specific cases. For example, Dong et al 49 model the crushing behavior of CFRP composite structure and show that a systematic approach can be developed to represent the post-lamina failure behavior including the residual strengths of the fiber and matrix, as well as the ultimate strain for element erosion.…”

Effect of stacking angles on crashworthiness of CFRP square tubes considering low-velocity impact damage

“…[1][2][3][4][5][6][7][8] However, despite their good mechanical properties and excellent energy absorption, composites are quite sensitive to low-velocity impacts, and even almost unobservable damage may lead to a significant reduction in structural strength and stiffness. [9][10][11][12][13][14] Since composites will inevitably be affected by low-velocity impacts during service, it is of crucial significance to improve the residual mechanical properties of CFRP structures after being damaged by low-velocity impacts for more reliable and extensive applications.…”

Influence of the bevel and steeple triggers on crashworthiness of carbon fiber-reinforced composite channel section structure

“…Carbon fiber-reinforced composites have gradually replaced metal materials in aerospace because of their excellent properties such as high specific strength, and high specific stiffness. [1][2][3][4][5][6][7][8] The crashworthiness of the aircraft is closely related to the design of the composite energy-absorbing structure, which directly affects the safety of the occupants. [9][10][11][12] In collision accidents, the composite structure can dissipate a large amount of impact kinetic energy through complex failure modes such as fiber matrix damage, buckling failure, delamination, and folding.…”