A Tool For Teaching Stress Transformation By Mohr's Circle

The determination of transformed and principal stresses is frequently a significant conceptual hurdle for Mechanics of Materials students. Mohr’s circle is commonly introduced as a tool ostensibly to make the transformation concept easier to understand and apply. Yet learning the Mohr’s circle conventions frequently introduces an additional challenge. A computer program to assist the learning of stress transformation and Mohr’s circle is introduced. It displays diagrams of the state of stress and the corresponding Mohr’s circle as transformation angle is varied. Results of student testing indicate it is most effective at improving ability to anticipate the variation of stress magnitude as transformation angle varies and for identifying principal stresses on the circle.