If we think about steel or wood or any other material, the dimensions of the sample should have only a negligible effect on the measurement result. The reason is that the sample is orders of magnitude larger than the grain size of the steel or the cell size of the wood. In other words, the continuum theory applies.

However, if we consider cellular solids with a cell size of the order of millimeters, a sample of a few centimeter may show side effect, influencing largely the mesurement.

In this theoretical thesis, the different calculation methods are discussed to handle this problem. This may be important as a theoretical base for writing standards, EN or ASTM, where the dimensions of the samples are defined. It gives also an answer  which deviations like holes can be accepted.