Finite element model updating from full-field vibration measurement using digital image correlation

Computational biomechanical models are useful tools for supporting orthopedic implant design and surgical decision making, but because they are a simplification of the clinical scenario they must be carefully validated to ensure that they are still representative. The goal of this study was to assess the validity of the generation process of a structural finite element model of the proximal femur employing the digital image correlation (DIC) strain measurement technique. A finite element analysis model of the proximal femur subjected to gait loading was generated from a CT scan of an analog composite femur, and its predicted mechanical behavior was compared with an experimental model. Whereas previous studies have employed strain gauging to obtain discreet point data for validation, in this study DIC was used for full field quantified comparison of the predicted and experimentally measured strains. The strain predicted by the computational model was in good agreement with experimental measurements, with R2 correlation values from 0.83 to 0.92 between the simulation and the tests. The sensitivity and repeatability of the strain measurements were comparable to or better than values reported in the literature for other DIC tests on tissue specimens. The experimental-model correlation was in the same range as values obtained from strain gauging, but the DIC technique produced more detailed, full field data and is potentially easier to use. As such, the findings supported the validity of the model generation process, giving greater confidence in the model’s predictions, and digital image correlation was demonstrated as a useful tool for the validation of biomechanical models.

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Model updating of uncertain parameters of carbon/epoxy composite plates using digital image correlation for full-field vibration measurement

Measurement ◽

10.1016/j.measurement.2020.107783 ◽

2020 ◽

Vol 159 ◽

pp. 107783 ◽

Cited By ~ 2

Author(s):

M. Cuadrado ◽

J. Pernas-Sánchez ◽

J.A. Artero-Guerrero ◽

D. Varas

Keyword(s):

Digital Image Correlation ◽

Digital Image ◽

Model Updating ◽

Epoxy Composite ◽

Composite Plates ◽

Image Correlation ◽

Vibration Measurement ◽

Uncertain Parameters ◽

Full Field

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Identification of a 3D Anisotropic Yield Surface of X70 Pipeline Steel Using a Multi-DIC Setup

Volume 3: Operations, Monitoring and Maintenance; Materials and Joining ◽

10.1115/ipc2016-64380 ◽

2016 ◽

Cited By ~ 1

Author(s):

Kristof Denys ◽

Sam Coppieters ◽

Renaat Van Hecke ◽

Steven Cooreman ◽

Dimitri Debruyne

Keyword(s):

Mechanical Properties ◽

Digital Image Correlation ◽

Digital Image ◽

Model Updating ◽

Element Model ◽

Image Correlation ◽

Finite Element Model Updating ◽

Line Pipe ◽

Strain Fields ◽

Stereo Digital Image Correlation

A new method is proposed combining multiple synchronized digital image correlation setups (multi-DIC) and finite element model updating to identify the hardening behaviour and anisotropy of 23.5 mm thick X70 line pipe steel. Curved tensile samples have been cut from a coil. While performing a tensile test on those samples, the force was obtained from the load cell and the back and front surface strain fields were measured by means of two synchronized stereo digital image correlation setups. The tests on the curved samples are reproduced with FE simulations, applying the same boundary conditions as the experimental setup to obtain the numerical force and strain fields. While simultaneously minimising the discrepancy between the experimentally and numerically obtained force and strain fields, the strain hardening behaviour is identified beyond the point of maximum uniform elongation. A profound understanding of the anisotropy is also mandatory because the hot rolling operation develops substantial anisotropy which has an important influence on the line pipe performance. Due to the 23.5 mm thick steel that is used in this work, it is possible to measure the front and side surfaces with two synchronized stereo digital image correlation setups. Because full field information is available in all 3 material directions (lateral, longitudinal and through thickness direction), a 3D anisotropic yield criterion can be identified. A prerequisite for stable and accurate identification of the yield locus parameters is that the governing parameters are sufficiently sensitive to the experimentally measured response. For this purpose, a double perforated specimen has been designed which includes a side perforation. The latter guarantees the necessary through-thickness information to inversely identify the 3D anisotropic yield function through multi-DIC and finite element model updating. The presented procedure could potentially be used by line pipe manufactures to verify whether the mechanical properties meet the specified requirements. The proposed approach has some advantages compared to conventional methods to determine mechanical properties of large diameter pipe. The curved specimen geometry is modelled in the FE simulation, hence the detrimental effects of flatting the tensile specimen can be avoided. Further, the new approach enables to consider the complete wall thickness as opposed to conventional testing with round bar samples of which a part of the wall thickness is removed during manufacturing.

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Shape features and finite element model updating from full-field strain data

International Journal of Solids and Structures ◽

10.1016/j.ijsolstr.2011.02.010 ◽

2011 ◽

Vol 48 (11-12) ◽

pp. 1644-1657 ◽

Cited By ~ 56

Author(s):

Weizhuo Wang ◽

John E. Mottershead ◽

Christopher M. Sebastian ◽

Eann A. Patterson

Keyword(s):

Finite Element ◽

Finite Element Model ◽

Model Updating ◽

Element Model ◽

Field Strain ◽

Finite Element Model Updating ◽

Shape Features ◽

Full Field ◽

Strain Data

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A study of loading rate effect fracture behavior of concrete based on digital image correlation and finite-element method

The Journal of Strain Analysis for Engineering Design ◽

10.1177/0309324720948629 ◽

2020 ◽

pp. 030932472094862

Author(s):

Xudong Chen ◽

Chen Chen ◽

Xiyuan Cheng ◽

Chaoguo Wu ◽

Zhenxiang Shi ◽

...

Keyword(s):

Finite Element ◽

Digital Image Correlation ◽

Finite Element Model ◽

Digital Image ◽

Fracture Process ◽

Loading Rate ◽

Element Model ◽

Rate Effect ◽

Image Correlation ◽

Extended Finite Element

To study the rate effect on the fracture properties of concrete, 700 mm × 150 mm × 100 mm specimens with a 60-mm notch were used for three-point bending test at the loading rate of 0.0005, 0.005, 0.05, and 0.5 mm/s, respectively. In the test, digital image correlation was used for monitoring the fracture process. The result shows that the fracture stress, unstable fracture toughness, and fracture energy have rate sensitivity. The numerical simulation was performed by extended finite-element model. The model calibration had a very good agreement with the experimental result under different loading rate. Meanwhile, fracture process zone length calculated by digital image correlation is similar to the result obtained by the extended finite-element model under different loading rate.

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