Simulation of mixed mode I/II cyclic deformation at the tip of a short kinked inclined crack with frictional surfaces

This paper provides a study on mixed-mode fracture mechanics in thin-walled tube which is subjected to tension, shear and torsion loading. This type of loading causes an inclined crack to develop and generate a mixture of normal and shear stresses ahead of a crack tip. The stress state ahead of a crack tip is frequently based on mixed-mode type of interactions which designate the amplitude of the crack tip stresses. The analytical expressions for the stress intensity factors for mixed-mode I + II approach are presented. The Paris law for mixed-modes I + II has been discussed. Mixed-mode fracture mechanics is used with theoretical models to predict the path of crack growth when an inclined crack is subjected to a combination of mode I and mode II deformations. The torque at which crack propagation can be expected has been determined. The numerical calculations have been carried out by using MATLAB code. The results are good and could be useful for companies working with thin-walled circular tubes.

Download Full-text

Evaluation of inclined crack in mixed mode I and II

Journal of Engineering Research ◽

10.36909/jer.10131 ◽

2021 ◽

Vol 9 ◽

Author(s):

Mohamed Tahar Hannachi ◽

◽

Mohamed Bradji ◽

Keyword(s):

Stress Intensity Factor ◽

Stress Intensity ◽

Intensity Factor ◽

Mixed Mode ◽

Critical Energy ◽

Mode I ◽

Inclined Crack ◽

Ductile Rupture ◽

Treated Steel ◽

Mode Of Failure

In this work,we tented to study the mixed mode of failure with two angles of inclination, of a treated steel, for that we tried to determine the parameters of failure as the stress intensity factor, tenacity and the critical energy in mixed mode of a rupture and see the criterion of rupture and seeing the effect of the angles evolution applied for all parameters. of in our close there is a fragile and less ductile rupture.

Download Full-text

Analysis of Mixed-Mode I/II/III Fracture Toughness Based on a Three-Point Bending Sandstone Specimen with an Inclined Crack

Applied Sciences ◽

10.3390/app11041652 ◽

2021 ◽

Vol 11 (4) ◽

pp. 1652

Author(s):

Xin Pan ◽

Jiuzhou Huang ◽

Zhiqiang Gan ◽

Shiming Dong ◽

Wen Hua

Keyword(s):

Fracture Toughness ◽

Mixed Mode ◽

Mode I ◽

Mixed Mode Fracture ◽

Pure Mode ◽

Inclined Crack ◽

Tangential Strain ◽

Mode Fracture ◽

Fracture Parameters ◽

T Stress

The crack-propagation form may appear as an arbitrary mixed-mode fracture in an engineering structure due to an irregular internal crack. It is of great significance to research the mixed-mode fracture of materials with cracks. The coupling effect of multiple variables (crack height ratio, horizontal deflection angle and vertical deflection angle) on fracture parameters such as the stress intensity factors and the T-stress are the key points in this paper. A three-point bending specimen with an inclined crack was proposed and used to conduct mixed-mode fracture research. The fracture parameters were obtained by finite element analysis, and the computed results showed that the pure mode I fracture and mixed-mode fractures (mode I/II, mode I/III and mode I/II/III) can be realized by changing the deflection angles of the crack. The pure mode I and the mixed-mode fracture toughness of sandstone were obtained by a series of mixed-mode fracture experiments. The experimental results were analyzed with the generalized maximum tangential strain energy density factor criterion considering T-stress. The results showed that the non-singular term T-stress in the fracture parameters cannot be ignored in any mixed-mode fracture research, and the generalized maximum tangential strain energy density factor criterion considering T-stress can better predict the mixed-mode fracture toughness than other criteria.

Download Full-text

Mixed Mode I/II Fracture Analysis of Bi-Material Adhesive Bonded Joints Using a Novel Short Beam Specimen

Applied Sciences ◽

10.3390/app11115232 ◽

2021 ◽

Vol 11 (11) ◽

pp. 5232

Author(s):

Mohammad Reza Mohammad Aliha ◽

Hadi Ghesmati Kucheki ◽

Mirmilad Mirsayar

Keyword(s):

Mixed Mode ◽

Fracture Initiation ◽

Shear Mode ◽

Mode I ◽

Beam Specimen ◽

Pure Mode ◽

Inclined Crack ◽

Cracking Behavior ◽

Test Configuration ◽

Fracture Parameters

Until now, some test specimens with different shapes and loading mechanisms have been utilized for investigating the cracking behavior of adhesive bounded joints. In this research, using a novel test configuration called adhesive short bend beam specimen containing an inclined crack and loaded by three-point bending, mixed mode I/II fracture parameters of a crack initiated in the adhesive part is studied. Compared to other test methods, the specimen used in this research needs a lesser amount of material and the fracture test can be performed easily. A large number of finite element models of this specimen were analyzed using ABAQUS code to study the effect of adhesive and adherent type, and also the crack length and loading span distance on KI, KII, T-stress and fracture initiation direction under different mode mixities. The results showed that the fracture parameters (and in particular the shear mode component) are sensitive to the type and location of adherent in the bounded joint; however, the shape and size of fracture plastic zone is not affected noticeably by the type of adhesive-adherent materials. It was also shown that the complete mode mixities ranging from pure mode I to pure mode II can be introduced for adhesive bounded joints using the proposed test specimen and therefore the specimen is a good candidate test configuration for investigating the mixed mode I/II fracture behavior of adhesive bounded joints.

Download Full-text