A Novel Multiscale Physics-Based Progressive Damage and Failure Modeling Tool for Advanced Composite Structures.

Composites;Multiscale Modeling;Continuum Damage Modeling;Mechanical Engineering;Engineering;Mechanical Engineering

Pineda, Evan JorgeWineman, Alan S. ;

University of Michigan

关键词: Composites;    Multiscale Modeling;    Continuum Damage Modeling;    Mechanical Engineering;    Engineering;    Mechanical Engineering;   

Others  :  https://deepblue.lib.umich.edu/bitstream/handle/2027.42/91483/ejpineda_1.pdf?sequence=1&isAllowed=y

瑞士|英语

来源: The Illinois Digital Environment for Access to Learning and Scholarship

【 摘 要 】

A novel, multiscale mechanics model for predicting the evolution ofdamage and failure in continuous fiber-reinforced laminates wasdeveloped.The thermodynamically-based work potential internalstate variable (ISV) theory, Schapery theory (ST), is utilized tomodel matrix microdamage at the lamina level within a finite elementmethod (FEM) setting.Failure due to transverse cracking and fiberbreakage is modeled at the microscale within a repeating unit cell(RUC) using the semi-analytical generalized method of cells (GMC). Amultiscale procedure is employed to link the microscale GMCcalculations to the macroscale at every integration point in the FEMmodel. Micromechanics calculations are precluded if the macroscaledamage is below some nominal value, increasing the overallcomputational efficiency of the multiscale scheme.Computationalresults and predicted failure modes are compared to experimentaldata of two center-notched, carbon fiber/epoxy panels containingdifferent stacking sequences. A novel, single-scale extension of ST,the enhanced Schapery theory (EST), is also presented.Threeadditional ISVs are introduced to account for failure via matrixtransverse cracking (mode I and mode II) and fiber breakage (mode Ionly). These ISVs incorporate a characteristic finite element lengthscale, and are directly related to the fracture toughnesses of thematerial.In doing so, the pathological mesh dependency, resultingfrom the failure degradation scheme that was used in the previousmultiscale model is eliminated; however, the explicit influence ofthe fiber-matrix architecture is lost.The EST model is evaluatedagainst the same center-notched panel data. Finally, a meshobjective, smeared crack band model is implemented into thehigh-fidelity generalized method of cells (HFGMC) micromechanicstheory.This failure model utilizes local fields to resolve theorientation of the crack band locally within the subcells of theRUC.The capabilities of the model are demonstrated using an RUCcontaining multiple randomly oriented fibers subjected to transversetension and compression.The results of the model are compared toexperimental data, and it is concluded that the newly developedmodel is viable for mesh objective, multiscale simulations.