Stress measurment - Book Report/Review Example

Although photoelasticity has been in use since many years, in the present times, its use in the measurement and analysis of stress has developed with the increasing development in technology, particularly with the development of computers. Computers have enabled the enhancement of numerical techniques required for effective measurement of stress. The application of the use of photoelasticity in the measurement of stress has further enhanced with the recent developments in laser, fiber optics, image analysis, and acquisition of data (Chapter 4: Photoelasticity n.d.).

The present study focuses on the principle of stress measurement using photoelastic technique, and use of strain gauges, trying to understand the physical principle on which the technology is based and the procedure that is used for the stress measurement technique. Fundamentals of Photoelasticity: Considering a photoelastic material, the field of stress obtained on the material can be associated with its refraction index (Singh 2010). The index of refraction can be understood through Maxwell’s stress optic laws. . The use of photoelastic technique is mainly done to effectively determine the difference in the principle stress on a material.

Thus it allows determining the maximum level of shear stress at different points on a material. It also helps in determining the values of the boundary stresses and directions of the stress on the material. In many cases, different values of principal stresses at different points on a material other than the boundary are also necessary to be obtained. This makes it necessary for the use of certain procedures of stress separation. Photoelasticity is one such technique that proves to be beneficial in this regard (Hearn 1997).

Photoelastic Technique for Stress Measurement: Considering measurement of stress in a material, photoelasticity technique can be used for measuring different components of the stress spread across different planes of the material. Three-in-plane components of stress are available on a two-dimensional photoelastic material. The observations of the complex factors of transmission enable measurement of the stress. It obtains the reduction of the optics and changes that occur in the different phases that are consequent from the birefringence in the material followed by stress (Sciammarella and Furlong 2013).

Photoelasticity is particularly useful for analysis of stress on materials that are highly complicated in terms of their geometry and/or loading conditions that are highly complicated in nature (Doyle and Phillips n.d.). Physical Principle on which the Technology is based: The technique of photoelasticity is primarily based on certain particular properties of materials like plastics, properties that are unique in nature and combination. For example, a model is considered