The following colour plates refer to topics covered in the text. They result from finite element computations performed with the software CASTEM2000 [CAS 92]. A symbolic colour scale is used as a particularly convenient manner to visualise the space distribution of elastic stress and support reaction fields induced on structural elements by static loads. Depending on the case, the stress isovalues are shown either on the non deformed or the deformed structure. Salient qualitative features of the results are briefly discussed here to illustrate interesting points discussed in a more general and abstract way in the text.

plate 1: Axial stress field induced by an axial force applied to the external contour of one base of a thick cylindrical shell of revolution

The thickness ratio of the shell is ? = 0.5 and aspect ratio is ? = 5. The shell is rigidly fixed at the right-hand side base and left free at the other. The material is steel. The external contour of the free base is loaded by an axial force density, distributed according to Fourier even harmonics. The finite element model uses massive cubical elements with eight nodes. In the case n = 0, a concentration of stresses is clearly evidenced by the red coloured zone in the immediate vicinity of the loaded contour. The blue colour indicates a stress level less than the peak value by a factor of at least ten. For n = 2 to n = 6, the...