scholarly journals Finite element model to simulate crack propagation based on local fracture stress criterion

2016 ◽  
Vol 2 ◽  
pp. 2558-2565 ◽  
Author(s):  
Yo Nishioka ◽  
Kazuki Shibanuma ◽  
Katsuyuki Suzuki ◽  
Fuminori Yanagimoto
2019 ◽  
pp. 147592171986572
Author(s):  
Chang Qi ◽  
Yang Weixi ◽  
Liu Jun ◽  
Gao Heming ◽  
Meng Yao

Fatigue crack propagation is one of the main problems in structural health monitoring. For the safety and operability of the metal structure, it is necessary to monitor the fatigue crack growth process of the structure in real time. In order to more accurately monitor the expansion of fatigue cracks, two kinds of sensors are used in this article: strain gauges and piezoelectric transducers. A model-based inverse finite element model algorithm is proposed to perform pattern recognition of fatigue crack length, and the fatigue crack monitoring experiment is carried out to verify the algorithm. The strain spectra of the specimen under cyclic load in the simulation and experimental crack propagation are obtained, respectively. The active lamb wave technique is also used to monitor the crack propagation. The relationship between the crack length and the lamb wave characteristic parameter is established. In order to improve the recognition accuracy of the crack propagation mode, the random forest and inverse finite element model algorithms are used to identify the crack length, and the Dempster–Shafer evidence theory is used as data fusion to integrate the conclusion of the two algorithms to make a more accountable and correct judge of the crack length. An experiment has been conducted to demonstrate the effectiveness of the method.


2015 ◽  
Vol 665 ◽  
pp. 173-176 ◽  
Author(s):  
Zdeněk Majer ◽  
Luboš Náhlík ◽  
Pavel Hutař

The particulate composites with glass matrix are widely used in many engineering applications. The mismatch of coefficients of thermal expansion during the fabrication process usually causes the presence of the residual stresses around particles. The influence and the understanding of the effects of residual stresses on the material response is required. The main aim of the present paper was to create a two-dimensional finite element model to analyze the influence of residual stresses on micro-crack behavior of glass and ceramics-based particulate composites. The maximum tangential stress criterion (MTS) was used to predict the direction of the micro-crack propagation. The modelled material was a kind of Low Temperature Co-fired Ceramics (LTCC) containing alumina particles embedded in a glass matrix. The influence of the micro-crack length and magnitude of loading on the micro-crack propagation path were investigated. The finite element software ANSYS was used. Conclusions of this paper can contribute to a better understanding of the propagation of micro-cracks in particulate composites in the field of residual stresses.


Sign in / Sign up

Export Citation Format

Share Document