A Modified Lemaitre Damage Model Phenomenologically Accounting for the Lode Angle Effect on Ductile Fracture

Abstract This paper presents a numerical study on pipes ductile fracture mechanical response using a phenomenological computational damage model. The damage is controlled by an initiation criterion dependent on the stress triaxiality and the Lode angle parameter, and a post-initiation damage law to eliminate each finite element from the mesh. Experimental tests were carried out to calibrate the elastoplastic response, damage parameters and validate the FEM models. The tested geometries were round bars having smooth and notched cross-section, flat notched specimens under axial tensile loads, and fracture toughness tests in deeply cracked bending specimens SE(B) and compact tension samples C(T). The calibrated numerical procedure was applied to execute a parametric study in pipes with circumferential surface cracks subjected to tensile and internal pressure loads simultaneously. The effects of the variation of geometric parameters and the load applications on the pipes strain capacity were investigated. The influence of longitudinal misalignment between adjacent pipes was also investigated.

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Multi-surface Cyclic Plasticity Sand Model with Lode Angle Effect

Geotechnical and Geological Engineering ◽

10.1007/s10706-007-9170-3 ◽

2007 ◽

Vol 26 (3) ◽

pp. 335-348 ◽

Cited By ~ 24

Author(s):

Zhaohui Yang ◽

Ahmed Elgamal

Keyword(s):

Cyclic Plasticity ◽

Angle Effect ◽

Lode Angle

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IMPLEMENTATION OF THE LEMAITER DAMAGE MODEL IN ANSYS FINITE ELEMENT COMPLEX

Transactions of Academenergo ◽

10.34129/2070-4755-2020-61-4-30-48 ◽

2020 ◽

pp. 30-48

Author(s):

D.A. Kosov ◽

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D.I. Fedorenkov ◽

A.V. Tumanov ◽

◽

...

Keyword(s):

Finite Element ◽

Numerical Experiment ◽

Numerical Experiments ◽

Damage Accumulation ◽

Cylindrical Specimen ◽

Damage Model ◽

Finite Element Calculation ◽

Element Calculation ◽

Lemaitre Damage Model ◽

Calculation Software

In this work, the simplified Lemaitre damage model was integrated into the ANSYS finite element calculation software. The model is implemented as a dynamically linked library of custom material for 2D problems. The model was tested on a cylindrical specimen with an annular cut. The stages of damage accumulation in the numerical experiment coincide with similar numerical experiments known in the literature.

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A Cross Integration for von-Mises Plasticity Along with Nonlinear Isotropic Hardening and Lemaitre Damage Model

Iranian Journal of Science and Technology Transactions of Mechanical Engineering ◽

10.1007/s40997-020-00404-2 ◽

2020 ◽

Author(s):

Maliheh Tavoosi ◽

Mehrzad Sharifian ◽

Mehrdad Sharifian

Keyword(s):

Damage Model ◽

Isotropic Hardening ◽

Mises Plasticity ◽

Lemaitre Damage Model ◽

Von Mises ◽

Von Mises Plasticity

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Ductile Tearing Simulation of Circumferential Cracked Pipe Under Cyclic Loading Using Damage Criteria Determined by Monotonic Pipe Test Data

Volume 6A: Materials and Fabrication ◽

10.1115/pvp2018-84588 ◽

2018 ◽

Author(s):

Jin-Ha Hwang ◽

Gyo-Geun Youn ◽

Naoki Miura ◽

Yun-Jae Kim

Keyword(s):

Fracture Toughness ◽

Cyclic Loading ◽

Ductile Fracture ◽

Test Data ◽

Strain Energy ◽

Fracture Strain ◽

Damage Model ◽

Fracture Toughness Test ◽

Ductile Tearing ◽

Damage Criteria

To evaluate the structural integrity of nuclear power plant piping, it is important to predict ductile tearing of circumferential cracked pipe from the view point of Leak-Before-Break concept under seismic conditions. CRIEPI (Central Research Institute of Electric Power Industry) conducted fracture test on Japanese carbon steel (STS410) circumferential through-wall cracked pipes under monotonic or cyclic bending load in room temperature. Cyclic loading test conducted variable experimental conditions considering effect of stress ratio and amplitude. In the previous study, monotonic fracture pipe test was simulated by modified stress-strain ductile damage model determined by C(T) specimen fracture toughness test. And, ductile fracture of pipe under cyclic loading simulated using damage criteria based on fracture strain energy from C(T) specimen test data. In this study, monotonic pipe test result is applied to determination of damage model based on fracture strain energy, using finite element analysis, without C(T) specimen fracture toughness test. Ductile fracture of pipe under variable cyclic loading conditions simulates using determined fracture energy damage model from monotonic pipe test.

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