Assessment of local strain field in adhesive layer of an unsymmetrically repaired CFRP panel using digital image correlation

PurposeThe purpose of this paper is to develop a methodology for in situ stress intensity factor (SIF) determination that can be used for the analysis of cracked structures. The technique is based on digital image correlation (DIC) combined with an overdetermined algorithm.Design/methodology/approachThe linear overdeterministic algorithm for calculating the SIF based on stress values around the crack tip is applied to a strain field obtained by DIC.FindingsAs long as the image quality is sufficiently high, a good accuracy can be obtained for the measured SIF. The crack tip can be automatically detected based on the same strain field. The use of the strain field instead of the displacement field, eliminates problems related to the rigid body motion of the analysed structure.Practical implicationsIn future works, based on the applied techniques, the SIF of complex cracked plane stress structures can be accurately determined in real engineering applications.Originality/valueThe paper demonstrates application of known techniques, refined for other applications, also the use of stress field for SIF overdeterministic calculations.

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Cross Weld Tensile Testing With Digital Image Correlation to Determine Local Strain Response

10.1115/1.0000191v ◽

2021 ◽

Author(s):

William Siefert ◽

James Rule ◽

Boian Alexandrov ◽

Jorge Penso ◽

Michael P. Buehner

Keyword(s):

Digital Image Correlation ◽

Digital Image ◽

Tensile Testing ◽

Local Strain ◽

Image Correlation ◽

Strain Response

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Predicting strains in embedded reinforcement based on surface deformation obtained by digital image correlation technique

10.2749/ghent.2021.0425 ◽

2021 ◽

Author(s):

Ali Mirzazade ◽

Cosmin Popescu ◽

Thomas Blanksvärd ◽

Björn Täljsten

Keyword(s):

Digital Image Correlation ◽

Digital Image ◽

Surface Deformation ◽

Local Strain ◽

Surface Strain ◽

Image Correlation ◽

Correlation Technique ◽

Proposed Model ◽

Structural Inspection ◽

Semi Empirical

<p>This study is carried out to assess the applicability of using a digital image correlation (DIC) system in structural inspection, leading to deploy innovative instruments for strain/stress estimation along embedded rebars. A semi-empirical equation is proposed to predict the strain in embedded rebars as a function of surface strain in RC members. The proposed equation is validated by monitoring the surface strain in ten concrete tensile members, which are instrumented by strain gauges along the internal steel rebar. One advantage with this proposed model is the possibility to predict the local strain along the rebar, unlike previous models that only monitored average strain on the rebar. The results show the feasibility of strain prediction in embedded reinforcement using surface strain obtained by DIC.</p>

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A new methodology to identify minimum strain anatomical lines based on 3-D digital image correlation

Mechanical Sciences ◽

10.5194/ms-8-337-2017 ◽

2017 ◽

Vol 8 (2) ◽

pp. 337-347 ◽

Cited By ~ 2

Author(s):

Jorge Barrios-Muriel ◽

Francisco Javier Alonso Sánchez ◽

David Rodríguez Salgado ◽

Francisco Romero-Sánchez

Keyword(s):

Digital Image Correlation ◽

Digital Image ◽

Strain Field ◽

Three Dimensional ◽

Wearable Devices ◽

Plane Motion ◽

Human Motion ◽

The Body ◽

Image Correlation ◽

Minimum Deformation

Abstract. Today there is continuous development of wearable devices in various fields such as sportswear, orthotics and personal gadgets, among others. The design of these devices involves the human body as a support environment. Based on this premise, the development of wearable devices requires an improved understanding of the skin strain field of the body segment during human motion. This paper presents a methodology based on a three dimensional digital image correlation (3D-DIC) system to measure the skin strain field and to estimate anatomical lines with minimum deformation as design criteria for the aforementioned wearable devices. The errors of displacement and strain measurement related to 3-D reconstruction and out-of-plane motion are investigated and the results are acceptable in the case of large deformation. This approach can be an effective tool to improve the design of wearable devices in the clinical orthopaedics and ergonomics fields, where comfort plays a key role in supporting the rehabilitation process.

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