Photoelastic Studies on the Plane Stresses Produced by Moving Loads

Abstract

A study is made on the plane stress fields produced in a plate by a moving load, and the general expressions for steady stress fields are obtained. Using those expressions, the stress fields due to a concentrated force moving in a plate or along its edge are calculated. The results are compared with those of the experiments by dynamic photoelasticity method with polyurethan rubber. Comparisions are made for three speed ranges : subsonic, transonic and supersonic. The ptotoelastic fringe patterns coincide fairly well with the calculated isochromatic lines if the load speed does not exceed the propagation velocity of the longitudinal stress waves.