Photoelastic methods wiki

The general aim of this website is to share different projects on how to make, image, analyze and use photoelastic materials. This was initially a wiki (and still is if you want to participate) built by this group of persons.

A lot of publications have been written on these topics but here we go into details, we show each method step by step, we give tips, and you can ask specific questions and get answers...

Direct links

For those who know what they are looking for, here is the list of the main pages accessible in this wiki:

• Theoretical aspects on the photoelasticimetry
• The methods to make photoelastic samples:
  • Cutting samples out of a sheet
  • Molding samples with urethane
  • Molding samples from gels
  • 3D printed samples
• The methods to image loaded photoelastic materials:
  • Using different wavelengths
  • Using transmission photoelasticity method
  • Using reflection photoelasticity method
  • Using terahertz photoelasticity method
• The methods to post-process images:
  • Detect and follow particles
  • Analysing qualitative image intensity
  • Computing the $G^2$ to get average stress
  • Inverting the problem to get force measurements
• Gallery
• Questions and answers
• Toward photoelasticity.net

What is the global purpose of this group?

Photoelasticity is a fantastic way to see what is usually invisible in mechanics: strain and stress. It can be used for educational, scientific, industrial, and even artistic purposes. However, it is not always easy to understand how it works, with which material and how to image it. The purpose of this wiki is to give an overview of the different methods to deal with photoelasticity:

• How to make samples?
• How to image?
• How to analyze data?

This wiki is mainly managed by people interested in granular physics so most of the examples and methods given here are dedicated to the experimental study of granular matter. It does not mean that people interested in a different field will not find what they are looking for about photoelasticity. It just means that people interested in or willing to study the marvelous and mysterious world of granular matter can find many details about how to set up and run an experiment with photoelastic particles and how to post-process images.
The different sections of this wiki refer to many scientific publications. This wiki itself is directly linked to a review paper to be published in Granular Matter. We also report here this very nice review paper on imaging methods in granular physics. Both papers deal with most of the points detailed in this wiki.

Who is participating in this group?

Here is the list of people and institutions who make this wiki alive. Please, feel free to join us) if you want to share your experience with photoelasticimetry. The information shared here represents many years of research, so please, remember to acknowledge this work by citing this wiki or the different publications if you use information you have found here for research. For other users please refer to the terms of the licence.

Why should I participate in this group?

We have chosen a wiki framework on top of a classical publication because we believe that it permits many people to continuously bring their knowledge and answer to other people wandering about the different methods.

How can I participate in this group?

You can have something to bring to the group or simply have something to ask. If you want to add articles to this website or make corrections to an existing one, send an email to jb[â]jonathan-bares.eu with an institutional email address, and we will create an account for you to modify the content.