Uniform and non-uniform stress distributions
This demonstration shows the effect of non-uniform stress distribution.
Fig. 6-4: Uniform and non-uniform stress distributions (The model demonstration was provided by Mr. P Palmer, University of Brighton)
Place a wooden block on a long sponge and apply a concentrated force at the centre of the block as shown in Fig. 6-4a. The sponge under the block deforms uniformly. If the concentrated force is placed at one end of the block as shown in Fig. 6-4b, the wooden block rotates with part of the block remaining in contact with the sponge and part separating from the sponge. It can be observed that the sponge deforms non-uniformly indicating a non-uniform stress distribution in the sponge.