2087
Proceedings of the 18
th
International Conference on Soil Mechanics and Geotechnical Engineering, Paris 2013
Structural Optimization in Geotechnical Engineering
Optimisation de la structure dans la géotechnique
T. Pucker & J. Grabe
Hamburg University of Technology, Institute of Geotechnical Engineering and Construction Management
ABSTRACT: Structural optimization methods are used for a wide range of engineering problems. In geotechnical engineering
however, only limited experience exists with these methods. The possibilities and difficulties in applying such techniques to
geotechnical problems are discussed in this paper and the adaption of the commonly known SIMP-method (Solid Isotropic Material
with Penelization) to geotechnical problems is introduced. An application example is used to demonstrate the potential of structural
optimization in geotechnical engineering.
RÉSUMÉ
: Des méthodes de l’optimisation de la structure sont employés dans beaucoup de disciplines d’ingénieurs. Mais il y a
quand-
même peu d’expériences dans le domaine de la géotechnique. Les possibilités et les difficultés de l’application de ces
procédures d’optimisation dans la géotechnique sont discutées dans cet article. L’application de la méthode SIMP est présenté. Un
exemple est présenté pout montrer le potentiel de l’application de cette méthode.
KEYWORDS: topology, optimization, optimisation
1 INTRODUCTION
Structural optimization methods are used for a wide range of
engineering problems, for instance in aviation and automotive
engineering. In geotechnical engineering however, only limited
experience exists with such methods. The possibilities and
difficulties in applying these techniques to geotechnical
problems are discussed in this paper and the adaption of the
commonly known SIMP-method to geotechnical problems is
introduced.
1.1
Structural Optimization
Structural Optimization can be classified in three categories.
The first category is called topology optimization and describes
the main geometry of a design. Topology is a mathematical
field used to describe geometrical structures. A geotechnical
example of different topologies to stabilize a slope is shown in
Figure 1.
Figure 1a) shows the design problem. Different constructions
can be used to solve this task, for example a gravity wall
(Figure 1b), a single anchored wall (Figure 1c) or a grouted
anchored wall (Figure 1d). These three constructions differ in
their topology. Some topology optimization algorithms can be
found in Bendsøe (1995) or Allaire (2005).
Once a topology is chosen, the shape of the topology can be
optimized with regard to the design problem. Concerning the
design problem in Figure 1, the topology in Figure 1d is chosen.
Figure 2 shows different possibilities to optimize the shape of
the topology in Figure 1d during the category shape
optimization, for example the variation of the anchor positions
(b), of the anhor inclination (c) or the anchor length (d). The
variations in Figure 2 b)-d) can be varied regarding an
optimization task, for instance the minimization of the bending
of the wall or minimization of the installation costs. The
application of shape optimization algorithms in geotechnical
application has been shown in Kinzler (2007) and Grabe et al.
(2010, 2011).
The third category is the dimension optimization of each
construction part. Within this category every cross section and
dimension is determined. Neither the topology nor the shape can
be changed by the dimension optimization. The dimension
optimization is the most widely applied category of structural
optimization in geotechnical engineering. The shape
optimization of Figure 2 results in the shape shown in Figure 3.
For this example, possible parameters for the dimension
optimization are given in Figure 3.
Figure 1. Different topologies for a design problem a): b) gravity wall, c) single anchored wall, d) grouted anchored wall
Structural Optimization in Geotechnical Engineering
Optimisation de la structure dans la géotechnique
Pucker T., Grab J.
Hamburg University of Technology, Institute of Geotechnical Engineering and Construction Management
