Adaptive and highly accurate numerical treatment for a gradient‐enhanced brittle damage model

Based on micromechanics, an elastic-plastic-brittle damage model of concrete beam reinforced with stick steel is proposed by considering the aggregate gradation curve algorithms and the heterogeneity. In the model, the concrete beam reinforced with stick steel is taken as a five-phase composite material that consists of the mortar matrix, coarse aggregate, bonds between mortar and aggregate, steel plate, and the adhesive layer between steel plate and concrete beam. Through the numerical investigation on shear failure of concrete beam reinforced with stick steel under external force, the results show that the model can clearly simulate microscopic plastic yield, and the initiation and extension of crack. The strength of the steel plate is relatively stronger, so it cant enhance the shear capability of the each side of the beam and the concrete beam bears the larger shear stress, which results that a large number of elements, from the supports to the load points, begin to yield. When the strain of the elements exceeds the yield strength, the elements will produce failure until the failure of the whole specimen. The final failure mode of concrete beam reinforced with stick steel is the shear failure.

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A novel isotropic quasi-brittle damage model applied to LCF analyses of Al2024

International Journal of Fatigue ◽

10.1016/j.ijfatigue.2010.07.001 ◽

2010 ◽

Vol 32 (12) ◽

pp. 1948-1959 ◽

Cited By ~ 21

Author(s):

O. Kintzel ◽

S. Khan ◽

J. Mosler

Keyword(s):

Damage Model ◽

Brittle Damage

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A FAST AND ROBUST NUMERICAL TREATMENT OF A GRADIENT-ENHANCED MODEL FOR BRITTLE DAMAGE

International Journal for Multiscale Computational Engineering ◽

10.1615/intjmultcompeng.2018027813 ◽

2019 ◽

Vol 17 (2) ◽

pp. 151-180 ◽

Cited By ~ 6

Author(s):

Philipp Junker ◽

Stephan Schwarz ◽

Dustin R. Jantos ◽

Klaus Hackl

Keyword(s):

Numerical Treatment ◽

Brittle Damage

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Numerical Investigation on Bending Failure of Concrete Beam Strengthened by Bonded Steel Plate

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.671-674.906 ◽

2013 ◽

Vol 671-674 ◽

pp. 906-911

Author(s):

Bing Xu ◽

Da Guo Wang ◽

Zhi Xiu Wang

Keyword(s):

Numerical Investigation ◽

Concrete Beam ◽

Steel Plate ◽

Damage Model ◽

Adhesive Layer ◽

Aggregate Gradation ◽

Brittle Damage ◽

Plastic Yield ◽

Final Failure ◽

Bending Failure

Based on micromechanics, an elastic-plastic-brittle damage model of concrete beam strengthened by bonded steel plate is proposed by considering the aggregate gradation curve algorithms and the heterogeneity. In this model, the concrete beam strengthened by bonded steel plate is taken as a five-phase composite material that consists of the mortar matrix, coarse aggregate, bonds between matrix and aggregate, steel plate, and the adhesive layer between steel plate and concrete beam. Through the numerical investigation on bending failure of concrete beam strengthened by bonded steel plate under external force, the results show that the model can clearly simulate microscopic plastic yield, and the initiation and extension of crack. The strength of the steel plate is relatively lower and it firstly yield and damage, then the bending stress born on the steel plate is transferred to the concrete beam. This results that the inner cracks of concrete beam increase rapidly and coalesce until the failure of the whole specimen. The final failure mode of concrete beam strengthened by bonded steel plate is the ductile bending failure.

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Mesomechanics coal experiment and an elastic-brittle damage model based on texture features

International Journal of Mining Science and Technology ◽

10.1016/j.ijmst.2017.11.003 ◽

2018 ◽

Vol 28 (4) ◽

pp. 639-647 ◽

Cited By ~ 1

Author(s):

Chuanmeng Sun ◽

Shugang Cao ◽

Yong Li

Keyword(s):

Damage Model ◽

Texture Features ◽

Brittle Damage ◽

Model Based

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A Material Model for Prediction of Fatigue Damage and Degradation of CFRP Materials

Key Engineering Materials ◽

10.4028/www.scientific.net/kem.742.740 ◽

2017 ◽

Vol 742 ◽

pp. 740-744 ◽

Cited By ~ 2

Author(s):

Jörg Hohe ◽

Monika Gall ◽

Hannes Gauch ◽

Sascha Fliegener ◽

Zalkha Murni binti Abdul Hamid

Keyword(s):

Fatigue Damage ◽

Low Cycle Fatigue ◽

Damage Model ◽

Material Model ◽

Finite Element Program ◽

Damage Evolution Equation ◽

Brittle Damage ◽

Linear Elastic ◽

Element Program ◽

Definition Of

Objective of the present study is the definition of a material model accounting for fatigue damage and degradation. The model is formulated as a brittle damage model in the otherwise linear elastic framework. A stress driven damage evolution equation is derived from microplasticity considerations. The model is implemented as a user-defined material model into a commercial finite element program. In a comparison with experimental data in the low cycle fatigue regime, a good agreement with the numerical prediction is obtained.

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A geometrically inspired model for brittle damage in compressible elastomers

Journal of Applied Mechanics ◽

10.1115/1.4050620 ◽

2021 ◽

pp. 1-39

Author(s):

Sanhita Das ◽

Shubham Sharma ◽

Ananth Ramaswamy ◽

Debasish Roy ◽

J.N. Reddy

Keyword(s):

Phase Field ◽

Scale Parameter ◽

Damage Model ◽

Continuum Damage ◽

Surface Integral ◽

Brittle Damage ◽

Damage Models ◽

Damaged Material ◽

Isotropic Damage ◽

Pure Compression

Abstract Regularized continuum damage models such as those based on an order parameter (phase field) have been extensively used to characterize brittle damage of compressible elastomers. However, the prescription of the surface integral and the degradation function for stiffness lacks a physical basis. In this article we propose a continuum damage model that draws upon the postulate that a damaged material could be mathematically described as a Riemannian manifold. Working within this framework with a well defined Riemannian metric designed to capture features of isotropic damage, we prescribe a scheme to prevent damage evolution under pure compression. The result is a substantively reduced stiffness degradation due to damage before the peak response and a faster convergence rate with the length scale parameter in comparison with a second order phase field formulation that involves a quadratic degradation function. We also validate this model using results of tensile experiments on double notched plates.

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Elastic Brittle Damage Model of Ni-YSZ and Predicted Stress–Strain Relations as a Function of Temperature and Porosity

Journal of Fuel Cell Science and Technology ◽

10.1115/1.4003751 ◽

2011 ◽

Vol 8 (5) ◽

Author(s):

Gulfam Iqbal ◽

Bruce Kang

Keyword(s):

Anode Material ◽

Damage Model ◽

Material Degradation ◽

Stress Strain ◽

Element Analysis ◽

Brittle Damage ◽

Lower Load ◽

Higher Temperature ◽

Lower Temperature ◽

Sofc Stacks

Nickel-yttria stabilized zirconia (Ni-YSZ) is the most widely used material for solid oxide fuel cell (SOFC) anodes. Anode-supported SOFCs rely on the anode to provide mechanical strength to the positive–electrolyte–negative (PEN) structure. The stresses generated in the anode can result in the formation of microcracks that degrade its structural properties and electrochemical performance. In this paper, a brittle elastic damage model is developed for Ni-YSZ and implemented in finite element analysis with the help of a user-defined subroutine. The model is exploited to predict Ni-YSZ stress–strain relations at temperatures and porosities that are difficult to generate experimentally. It is observed that the anode material degradation depends on the level of strain regardless of the temperature at the same porosity: at higher temperature, lower load is required to produce a specified level of strain than at lower temperature. Conversely, the anode material degrades and fails at a lower level of strain at higher porosity at the same temperature. The information obtained from this research will be useful to establish material parameters to achieve optimal robustness of SOFC stacks.

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