ENGINEERING COMPONENTS GROW LIKE TREES

Biological structures consist of mechanical load carriers, which are highly optimized in terms of mechanical strength and minimum weight. It is demonstrated on some selected examples that a constant Mises‐stress at the surface of the biological component can be accepted as significant biological design rule. However, a general proof of this hypothesis seems to be impossible. It is discussed how ready‐grown biological designs can be transferred to engineering applications. A new method of structural shape optimization was developed because biological “components” do not always exist exactly in a shape ready to be copied for engineering use. The method is based on the computer‐simulation of tree growth which is performed by use of the “volumetric swelling” option or alternatively by stress‐controlled thermal expansion in the FEM‐code ABAQUS. A number of examples show that the growth of biological structures can be computer‐simulated very well and incidentally the “natural” loading case can be defined precisely. Technical applications show that the method is very efficient in structural shape optimization of 2 D and 3 D engineering structures. It is compared with other methods of structural optimization found in the literature. Copyright © 1990 Verlag GmbH & Co. KGaA, Weinheim