Photoelasticity describes changes in the optical properties of a material under mechanical deformation. It is a property of all dielectric media and is often used to experimentally determine the stress distribution in a material, where it gives a picture of stress distributions around discontinuities in materials. Photoelastic experiments (also informally referred to as photoelasticity) are an important tool for determining critical stress points in a material, and are used for determining stress concentration in irregular geometries. History The photoelastic phenomenon was first discovered by the Scottish physicist David Brewster, who immediately recognized it as stress-induced birefringence. That diagnosis was confirmed in a direct refraction experiment by Augustin-Jean Fresnel. Experimental frameworks were developed at the beginning of the twentieth century with the works of E. G. Coker and L. N. G. Filon of University of London. Their book Treatise on Photoelasticity, published in 1930 by Cambridge Press, became a standard text on the subject. Between 1930 and 1940, many other books appeared on the subject, including...

The measurement of residual stresses is of great relevance in the glass industry. The analysis of residual stress in glass is usually made by photoelastic methods because glass is a photoelastic material. This paper considers the determination of membrane residual stresses in glass plates by automatic digital photoelasticity in white light (RGB photoelasticity). The proposed method is applied to the analysis of membrane residual stresses in some tempered glass. The proposed method can effectively replace manual methods based on the use of white light, which are currently provided by some technical standards.

changes in the optical properties of a material under mechanical deformation

Fotoelastisitas adalah suatu metode eksperimental untuk mendeteksi tingkat distribusi dalam suatu material. Metode digunakan dalam kasus dimana metode matematika sangat rumit untuk dicari atau didefinisikan. Fotoelastisitas tidak seperti metode analisis. Metode ini memberikan gambar yang akurat dari tingkat distribusi, bahkan meskipun adanya diskontinuitas dari bahan tersebut. Metode ini merupakan metode yag tepat untuk mencari titik kritis dalam suatu material, dan digunakan untuk menentukan konsentrasi tegangan pada geometri yang teratur. Sejarah Fenomena fotoelastis pertama kali dijelaskan oleh seorang fisikawan asal Skotlandia, David Brewster. Fotoelastisitas dikembangkan pada awal abad kedua puluh, karya EGCoker dan LNG Filon dari Universitas London. Buku mereka yang berjudul Treatise on Photoelasticity yang dipublikasikan tahun 1930 oleh Percetakan Cambridge menjadi acuan dasar tentang teori ini. Antara tahun 1930 dan 1940 muncul buku lain dalam bahasa Rusia, bahasa Jerman dan bahasa Prancis yang membahas pada fenomena ini. Pada saat yang sama banyak pengembangan dari teori ini terjadi di lapangan. Perbaikan...

Transmission photoelasticity on scale models is shown to disclose the stress distribution within dry masonry walls. This distribution is found to be complicated by unilateral joints between elements, where 'randomness constrained within a geometrical scheme' of contact points occurs, so that stress percolation results highly localized, evidencing 'unloading islands' in a 'stress stream'. These findings are theoretically explained in Part II of this paper from both micromechanical and continuous modelling perspectives.

The highly localized stress distribution found within dry masonry walls through transmission photoelasticity in Part I of this article is explained both proposing a micromechanical model (based on a form of random cascade transmission of forces between bricks, which includes random coalescence additionally to random branching) and applying a phenomenological description (based on the extreme orthotropy of the equivalent homogeneous material).