Using graphics programs to help students understand strain

Abstract Commercially-available computer graphics programs can be effectively used to help students overcome their inaccurate expecta-tions of what happens during deformation of objects by homogeneous pure and simple shear. Many computer graphics packages allow stu-dents to draw an object on the screen and then to distort the object using commands that are the equivalents of pure shear and simple shear. As students create and deform objects, they develop a better visual under-standing of 1) the behavior of lines and angles during strain, 2) the differences between pure and simple shear, and 3) the significance of the principal directions of strain. Once students have developed an accurate intuitive understanding of strain, they can go on to tackle strain analysis armed with an arsenal of accurate visual images on which to rely as they work through the quantitative aspects of strain.