A Developed Damage Constitutive Model for Circular Steel Tubes of Reticulated Shells

2020 ◽  
Vol 20 (09) ◽  
pp. 2050106
Author(s):  
Sheng He ◽  
Haosen Wang ◽  
Stéphane P. A. Bordas ◽  
Peng Yu
Keyword(s):  
Constitutive Model ◽  
Damage Mechanics ◽  
Dynamic Instability ◽  
Damage Model ◽  
Nonlinear Dynamic Analysis ◽  
Continuum Damage Mechanics ◽  
Steel Tubes ◽  
Mapping Algorithm ◽  
Comparison Results ◽  
Damage Constitutive Model

The aim of this paper is that the precise description of damage behavior is crucial to well catch the mechanical behavior of structures in the dynamic numerical simulation, and address the issue on the coupled plastic-damage constitutive model for circular steel tubes of reticulated shells under severe earthquake. Continuum Damage Mechanics (CDM) constitutive model established by Lemaitre is reviewed at the beginning. Then, an improved damage model for circular steel tubes of reticulated shells is developed based on Lemaitre’s model by replacing the original damage evolution law with a new one suitable for circular steel tubes. In addition, we introduce the stress update process. In this procedure, the well-known operator split strategy, which leads to the standard elastic predictor/return mapping algorithm, is adopted to solve the evolution problem of the improved model. Exploiting user-defined material subroutine, the implementation of the model is achieved within software ANSYS using BEAM189 element. Finally, the dynamic response of reticulated shells under severe earthquake are numerically simulated with the proposed model and with the conventional Prandtl-Reuss model, respectively. The comparison results show that the consideration of material damage accumulation, on the one hand, may change the failure mode of reticulated shells from dynamic instability to strength failure; on the other, may reduce the dynamic ultimate load obviously. This consideration should be taken into account when conducting nonlinear dynamic analysis of reticulated shells.

scholarly journals Investigation on the Nonlinear Strength Properties and Damage Statistical Constitutive Model for Frozen Sandy Soils

2018 ◽  
Vol 2018 ◽  
pp. 1-15 ◽  
Author(s):  
De Zhang ◽  
Enlong Liu ◽  
Xingyan Liu ◽  
Ge Zhang ◽  
Xiao Yin ◽  
...  
Keyword(s):  
Experimental Data ◽  
Constitutive Model ◽  
Damage Mechanics ◽  
Sandy Soils ◽  
Continuum Damage Mechanics ◽  
Strength Properties ◽  
Principal Stresses ◽  
Confining Pressures ◽  
Damage Constitutive Model ◽  
Frozen Sandy Soil

There are many flaws, such as fissures, cavities, and inclusions, in geomaterials, which make their mechanical properties with great randomness and uncertainty. Upon loading, the soil structure gradually losses the bearing capacity due to the transformation from microdefects to macroscopic breakage bands. Based upon the experimental data of frozen sandy soils, a new nonlinear strength equation between the first and third principal stresses was proposed, and then the nonlinear strength properties for frozen sandy soils in σ-τ plane were analyzed. In addition, by assuming that the microstrength of frozen sandy soil obeys the Weibull distribution function, a statistical damage constitutive model was established based upon the framework of continuum damage mechanics (CDM), with few parameters and a high accuracy. Compared with experimental data, the new model can well grasp the nonlinear strength properties and simulate the stress-strain relationships under different confining pressures for frozen sandy soils.

A Physically Based Damage Constitutive Model for Stress Relaxation

2014 ◽  
Author(s):  
Yu Zhou ◽  
Xuedong Chen ◽  
Zhichao Fan ◽  
Yichun Han
Keyword(s):  
Stress Relaxation ◽  
Constitutive Model ◽  
Damage Mechanics ◽  
Model Comparison ◽  
Continuum Damage Mechanics ◽  
Reheat Cracking ◽  
Physically Based ◽  
Damage Constitutive Model ◽  
Evolution Behavior ◽  
The Continuum

A damage constitutive model for stress relaxation was proposed based on the continuum damage mechanics theory, in terms of the characteristics of damage induced by stress relaxation which is associated with reheat cracking. The effects of strain hardening and the precipitation and growth of carbides on the stress evolution behavior were considered in the present model. To validate the accuracy of the constitutive model, comparison of the predicted result provided by the model and the experimental data of stress relaxation for 2.25Cr-1Mo-0.25V ferritic steel was made. It is shown that the damage constitutive model can be used to predict the stress relaxation behavior and reheat cracking further for low alloy ferritic steels.

Constitutive Description for Drawing Limit of Magnesium Alloy Tube Based on Continuum Damage Mechanics

2009 ◽  
Vol 610-613 ◽  
pp. 951-954 ◽  
Author(s):  
Ying Tong ◽  
Guo Zheng Quan ◽  
Bin Chen
Keyword(s):  
Magnesium Alloy ◽  
Constitutive Model ◽  
Damage Mechanics ◽  
Continuum Damage Mechanics ◽  
Plastic Behavior ◽  
Continuum Damage ◽  
Rigid Plastic ◽  
Alloy Tube ◽  
Limit Graph ◽  
Damage Constitutive Model

The elasto-plastic behavior and the drawing limit of a kind of magnesium alloy tube were investigated based on the foundational theories of the larger deformation of material and continuum damage constitutive model. The corresponding finite element numerical algorithm was developed based on the constitutive model. The non-mandrel drawing limit graph according to the diameter at different tube thickness of an AZ31B tube with diameter 10mm at 250°C and drawing velocity 100mm/s was achieved, and safe & unsafe area got partitioned. The maximum damage value was evaluated to be 0.324 according to height reduction ratio limit and rigid-plastic FE analysis.

An Elastoplastic-anisotropic Damage Model for Concrete

2011 ◽  
Vol 261-263 ◽  
pp. 371-375
Author(s):  
Jun Liu ◽  
Gao Lin
Keyword(s):  
Effective Stress ◽  
Damage Mechanics ◽  
Damage Model ◽  
Nonlinear Behavior ◽  
Continuum Damage Mechanics ◽  
Anisotropic Damage ◽  
Softening Effect ◽  
Damage Constitutive Model ◽  
Structural Levels ◽  
Damage Tensor

An elastoplastic-anisotropic damage constitutive model for the description of nonlinear behavior of concrete is presented. The yield surface is developed in effective stress spaces, which takes into account the hardening effect and better match the experimental data. The stiffness degradation and softening effect are considered in the framework of continuum damage mechanics formulation. The second-order damage tensor is used to characterize the anisotropy induced by the orientation of microcracks. In order to simulate the unilateral effect, the elastic Helmholtz free energy is decomposed into a volumetric part and a deviatoric part. The different behavior under tensile and compressive loadings is modeled by using different variables in effective stress and damage tensor. Numerical results of the model accord well with experimental results at the material and structural levels.

scholarly journals Statistical Damage Model of Altered Granite under Dry-Wet Cycles

Symmetry ◽  
2019 ◽  
Vol 11 (1) ◽  
pp. 41 ◽  
Author(s):  
Xuxin Chen ◽  
Ping He ◽  
Zhe Qin ◽  
Jianye Li ◽  
Yanping Gong
Keyword(s):  
Constitutive Model ◽  
Normal Distribution ◽  
Uniaxial Compression ◽  
Damage Mechanics ◽  
Damage Model ◽  
Equivalent Strain ◽  
Uniaxial Compression Test ◽  
Damage Constitutive Model ◽  
Statistical Damage Constitutive Model ◽  
Statistical Damage

This paper presents a new statistical damage constitutive model using symmetric normal distribution. The broken rock microbody obeyed symmetric normal distribution and the equivalent strain principle in damage mechanics. The uniaxial compression tests of samples subjected to dry-wet cycles were performed. The damage model was established using the equivalent strain principle and symmetric normal distribution. The damage variable was defined by the elastic modulus under various dry-wet cycles. Parameters of the damage constitutive model were identified using MATLAB software, and the proposed model is verified to be in good agreement with uniaxial compression test results. Fracturing of the rock microbody is well described by symmetric normal distribution, and the proposed statistical damage constitutive model has good adaptability to the uniaxial compression stress-strain curve.

Cross-Ply Laminates under Static Three-Point Bending: A Numerical Development Model

2012 ◽  
Vol 498 ◽  
pp. 42-54 ◽  
Author(s):  
S. Benbelaid ◽  
B. Bezzazi ◽  
A. Bezazi
Keyword(s):  
Numerical Model ◽  
Damage Mechanics ◽  
Progressive Failure ◽  
Damage Model ◽  
Continuum Damage Mechanics ◽  
Failure Criteria ◽  
Continuum Damage ◽  
Damage Development ◽  
Element Analysis ◽  
Progressive Failure Analysis

This paper considers damage development mechanisms in cross-ply laminates using an accurate numerical model. Under static three points bending, two modes of damage progression in cross-ply laminates are predominated: transverse cracking and delamination. However, this second mode of damage is not accounted in our numerical model. After a general review of experimental approaches of observed behavior of laminates, the focus is laid on predicting laminate behavior based on continuum damage mechanics. In this study, a continuum damage model based on ply failure criteria is presented, which is initially proposed by Ladevèze. To reveal the effect of different stacking sequence of the laminate; such as thickness and the interior or exterior disposition of the 0° and 90° oriented layers in the laminate, an equivalent damage accumulation which cover all ply failure mechanisms has been predicted. However, the solution algorithm using finite element analysis which implements progressive failure analysis is summarized. The results of the numerical computation have been justified by the previous published experimental observations of the authors.

A Nonlinear Damage Model of Hardening-Softening Materials

2017 ◽  
Vol 140 (1) ◽  
Author(s):  
M. Ganjiani
Keyword(s):  
Damage Mechanics ◽  
Damage Model ◽  
Continuum Damage Mechanics ◽  
Tensile Tests ◽  
Internal Variable ◽  
Integration Algorithm ◽  
Finite Element Program ◽  
Variable Theory ◽  
Numerical Predictions ◽  
Type Variable

In this paper, an elastoplastic-damage constitutive model is presented. The formulation is cast within the framework of continuum damage mechanics (CDM) by means of the internal variable theory of thermodynamics. The damage is assumed as a tensor type variable and its evolution is developed based on the energy equivalence hypothesis. In order to discriminate the plastic and damage deformation, two surfaces named as plastic and damage are introduced. The damage surface has been developed so that it can model the nonlinear variation of damage. The details of the model besides its implicit integration algorithm are presented. The model is implemented as a user-defined subroutine user-defined material (UMAT) in the abaqus/standard finite element program for numerical simulation purposes. In the regard of investigating the capability of model, the shear and tensile tests are experimentally conducted, and corresponding results are compared with those predicted numerically. These comparisons are also accomplished for several experiments available in the literature. Satisfactory agreement between experiments and numerical predictions provided by the model implies the capability of the model to predict the plastic deformation as well as damage evolution in the materials.

scholarly journals A bi-dissipative damage model for concrete

2015 ◽  
Vol 8 (1) ◽  
pp. 49-65
Author(s):  
J. J. C. Pituba ◽  
W. M. Pereira Júnior
Keyword(s):  
Reinforced Concrete ◽  
Structural Engineering ◽  
Damage Mechanics ◽  
Damage Model ◽  
Continuum Damage Mechanics ◽  
Concrete Material ◽  
Framed Structures ◽  
Energy Equivalence ◽  
Proposed Model ◽  
Damage Processes

This work deals with an improvement of an anisotropic damage model in order to analyze reinforced concrete structures submitted to reversal loading. The original constitutive model is based on the fundamental hypothesis of energy equivalence between real and continuous media following the concepts of the Continuum Damage Mechanics. The concrete is assumed as an initial elastic isotropic medium presenting anisotropy, permanent strains and bimodularity induced by damage evolution. In order to take into account the bimodularity, two damage tensors governing the rigidity in tension or compression regimes are introduced. However, the original model is not capable to simulate the influence of the previous damage processes in compression regimes. In order to avoid this problem, some conditions are introduced to simulate the damage unilateral effect. It has noted that the damage model is agreement with to micromechanical theory conditions when dealing to unilateral effect in concrete material. Finally, the proposed model is applied in the analyses of reinforced concrete framed structures submitted to reversal loading. These numerical applications show the good performance of the model and its potentialities to simulate practical problems in structural engineering.

scholarly journals Constitutive Model for Concrete: An Overview

2015 ◽  
Vol 10 (Special-Issue1) ◽  
pp. 782-788 ◽  
Author(s):  
Mehdi Shekarbeigi ◽  
Hasan Sharafi
Keyword(s):  
Constitutive Model ◽  
Damage Mechanics ◽  
Constitutive Models ◽  
Continuum Damage Mechanics ◽  
Constitutive Modelling ◽  
Continuum Damage ◽  
Endochronic Theory ◽  
Small Deformations

In the last three decades, the constitutive modelling of concrete evolved considerably. This paper describes various developments in this field based on different approaches such anelasticity, plasticity, continuum damage mechanics, plastic fracturing, endochronic theory, microplane models, etc. In this article the material is assumed to undergo small deformations. Only time independent constitutive models and the issues related to their implementation are discussed

Sign in / Sign up

Export Citation Format

Share Document