5.2. DESIGN PROCEDURES CATEGORIZATION
According to the book “Shells structures for architecture, form
finding and optimization“. It distinguish three types of design pro-
cedures to achieve larger architectural enclosures [Adriaenssens &
Block, 2014]:
- Free-form: free-curved or sculptural shells are generated with-
out taking into consideration structural performance. If they are
shaped digitally, then they are often described by higher degree
polynomials.
- Mathematical, geometrical or analytical shells are directly de-
scribed by analytical functions. These functions are often chosen
for their convenience in performing further analytical calcula-
tions and their ability to describe a shell´s shape for fabrication
purposes. These are often lower degree polynomials (hyperbo-
loids, ellipsoids and hyperbolic or elliptic paraboloids) or trigono-
metric or hyperbolic functions (the catenary).
- Form-found shells include natural, hanging shapes associated
with the funicular structures of Antoni Gaudí, Frei Otto and
Heinz Isler, but also “strained” gridshells that feature bending
stresses. Their final shape is the result of attaining a state of static
equilibrium.
Normally hybrid form-active systems belong to the third type
of structures. The equilibrium is formed based on the boundary
conditions, geometric and physical properties of the elastic struc-
tural elements and topology. In this process the final geometry is
unknown, form finding is the generation of geometry. However,
the process may require some arbitrary starting geometry. The
structures that will be presented later, comes from the second and
third type. We use mathematical and geometrical models in order
to achieve optimization and the final form. The free-form archi-
tecture also will be studied in this document.
This rational starting point bring us a wide range of possibilities
in topology and open a scope to use them in several types of dou-
ble curvature surfaces. It is possible create a curvature based on
topology and elastic deformation. The final geometry of the pro-
posal cases studies is already known, but a little variations appear
over the skin. Also topology allow us to get easily compression
members with the same length, and it define the fabric patterning.
Figure B2: Physical Form-finding model. Case2-Phase2. Planks inside.
Figure B3: Physical Form-finding model. Case2-Phase2. Planks Outside.
-Adriaenssens, S. Block, P. Veenendaal,D.Williams,C. (2014). Shell structures for architecture. Form Finding and optimization.
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