scholarly journals Mixed Finite Element Computation of Energy Release Rate in Anisotropic Materials Based on Virtual Crack Closure-Integral Method

2021 ◽  
Vol 15 (57) ◽  
pp. 359-372
Author(s):  
Sami Derouiche ◽  
Salah Bouziane ◽  
Hamoudi Bouzerd

The material with anisotropic properties are becoming widely essential due to the ease to manipulate their mechanical properties in order to obtain a particular quality, insure safety or a specific behavior. Those kind of materials are considered anisotropic because their characteristics and behavior are dependent to every direction of the material’s orientation. In this work, the virtual crack closure-integral technique is implemented to a mixed finite element, in addition with the stiffness derivative procedure, to evaluate the energy release rate of crack extension in anisotropic materials. A simulation of a cracked edge rectangular plat with anisotropic characteristics is taken for example. The results obtained are in good agreement with the analytical results, making the proposed technique a good model for fracture investigation and allow it to study more complicated cases in future works.

2018 ◽  
Vol 46 (3) ◽  
pp. 130-152
Author(s):  
Dennis S. Kelliher

ABSTRACT When performing predictive durability analyses on tires using finite element methods, it is generally recognized that energy release rate (ERR) is the best measure by which to characterize the fatigue behavior of rubber. By addressing actual cracks in a simulation geometry, ERR provides a more appropriate durability criterion than the strain energy density (SED) of geometries without cracks. If determined as a function of crack length and loading history, and augmented with material crack growth properties, ERR allows for a quantitative prediction of fatigue life. Complications arise, however, from extra steps required to implement the calculation of ERR within the analysis process. This article presents an overview and some details of a method to perform such analyses. The method involves a preprocessing step that automates the creation of a ribbon crack within an axisymmetric-geometry finite element model at a predetermined location. After inflating and expanding to three dimensions to fully load the tire against a surface, full ribbon sections of the crack are then incrementally closed through multiple solution steps, finally achieving complete closure. A postprocessing step is developed to determine ERR as a function of crack length from this enforced crack closure technique. This includes an innovative approach to calculating ERR as the crack length approaches zero.


2014 ◽  
Vol 50 (5) ◽  
pp. 665-677 ◽  
Author(s):  
Bouziane Salah ◽  
Bouzerd Hamoudi ◽  
Boulares Noureddine ◽  
Guenfoud Mohamed

2021 ◽  
Vol 15 (56) ◽  
pp. 229-239
Author(s):  
Amina Mohamed Ben Ali ◽  
Salah Bouziane ◽  
Hamoudi Bouzerd

The use of composite materials is on the rise in different engineering fields, the main advantage of these materials for the aerospace industry is their low weight for excellent mechanical qualities. The analysis of failure modes, such as delamination, of these materials has received great attention from researchers. This paper proposes a method to evaluate the mode I Strain Energy Release Rate (SERR) of sandwich structures. This method associated a two-dimensional mixed finite element with virtual crack extension technique for the analysis of interfacial delamination of sandwich beams. A symmetrical Double Cantilever Beam (DCB) and asymmetrical Double Cantilever Beam (UDCB) have been analyzed in this study.  The comparison of the results obtained by this method and those found in the literature shows efficiency and good precision for the calculation of Strain Energy Release Rate (SERR).


Author(s):  
S. Bouziane ◽  
H. Bouzerd

The interfacial crack in bimaterials is a very interesting problem for composite materials and which has received particular attention from several researchers. In this study, we will propose a numerical modeling of the interfacial crack between two orthotropic materials using a special mixed finite element. For the calculation of the energy release rate, a technique, based on the association of the present mixed finite element with the virtual crack extension method, was used. The numerical model proposed, in this work, was used to study a problem of interfacial crack in bimaterials. Two cases were treated: isotropic and orthotropic bimaterials. The results obtained, using the present element, were compared with the values of the analytical solution and other numerical models found in the literature.


2008 ◽  
Vol 33-37 ◽  
pp. 85-90
Author(s):  
Wei Xie ◽  
Qi Qing Huang ◽  
Masanori Kikuchi

In the virtual crack closure method (VCCM), the energy release rate is computed based on the results of finite element calculation, and the stress intensity factor (SIF) is computed from the energy release rate. In this paper, the stress intensity factor of mixed-mode surface cracks under three point bending is studied by using the three dimensional modified virtual crack closure method (MVCCM). The modified virtual crack closure method is required to open one element face area whose shape is arbitrary and finite element widths are unequal across the crack front. The effect of the distance between the location of load and crack face, crack shape and crack depth to the stress intensity factor is also discussed, along with practical results and conclusions.


Volume 2 ◽  
2004 ◽  
Author(s):  
Saiphon Charoenphan ◽  
Apiwon Polchai

The energy release rates in human cortical bone are investigated using a hybrid method of experimental and finite element modeling techniques. An explicit finite element analysis was implemented with an energy release rate calculation for evaluating this important fracture property of bones. Comparison of the critical value of the energy release rate, Gc, shows good agreement between the finite element models and analytical solutions. The Gc was found to be approximately 820–1150 J/m2 depending upon the samples. Specimen thickness appears to have little effect on the plane strain condition and pure mode I assumption. Therefore the energy release rate can be regarded as a material constant and geometry independent and can be determined with thinner specimens. In addition, the R curve resulting from the finite element models during slow crack growth shows slight ductility of the bone specimen that indicates an ability to resist crack propagation. Oscillations were found at the onset of the crack growth due to the nodal releasing application in the models. In this study light mass-proportional damping was used to suppress the noises. Although this techniques was found to be efficient for this slow crack growth simulation, other methods to continuously release nodes during the crack growth would be recommended for rapid crack propagation.


Sign in / Sign up

Export Citation Format

Share Document