OK, so perhaps it's not quite that simple, but using the new ATOM technology in Abaqus you can optimise the topolology of your model based on loading conditions and constraints.

In the example shown here the model starts off as a simple U-shaped mesh, with flat upright sides and a floor platform. With loads and appropriate constraints applied, ATOM iterates through many solutions, each time modifying the mesh and topology based on anaysis results of the previous iteration. In this non-linear process the end result is a bridge shape fully optimised for the applied loads.

The animation shows the model with the structurally irrelevant elements removed - the optimal geometry 'grows' as the analysis progresses.