http://www.hybios.blogspot.comAbstract:
HYBIOS_HYbrid BIOStructures
explores the possibility of using innovative construction logistics that are
the result of hybridization of materials and methods.
The research mainly attempts
to explore the potential of coupling free form tensile structure fabrication
and concrete shell construction methods; to simplify the building process of
complex doubly curved concrete forms. These forms are valued for the potential
of creating interesting differentiated spatial qualities, obscuring the
transition between structural and spatial elements resulting in a more coherent
overall geometry.
Objectives:
The development of material systems has
always been a primary driver for the ambitious search of novelty in formal
explorations of architectural design. Concrete has been a specifically
interesting material to develop, due to its fluid and flexible nature. The
processes made available by current building construction advancements gave
rise to a whole new range of possibilities for using concrete as a building
material. However, most of the methods previously experimented with have many
restraints, especially with creating ecologically feasible geometrically
elaborate tectonics. The high costs of
CNC milling, the excess of material used in the casting process and the
expensive specialized labour it requires keeps the method restrained to high
budget projects achievable only by large-scale economies.
The informal complexity of structures found
in nature is derived from simple processes and starting elements. These methods
are seen as an inspiration to create simple means of construction that could be
carried out by translating a set of instructions as forces that could generate
shape change on the material. Complex spatial qualities and structural elements
are hence seen as a resultant of these simple procedures and inexpensive
materials. Nature is extremely efficient in its material disposition, as seen
in formations where radical change in structural systems is gradually achieved
in a smooth gradient of transition. Following natural formation to achieve a
built man-made enclosure is seen a means to achieve the biotope building, an
ecological building of minimal material use and maximal performance efficiency.
Feedback Loops:
Physical and digital
experiments were carried out as an initial step towards achieving coherence in
space. Analogue prototypes in fabric helped to develop simple techniques in the
fabrication process to realize the forms. Scaling up of these forms and
materials were one of the biggest challenges that had to be resolved through
detailed material experimentations. The process is split into material
experimentation, analysis of the structural stiffness using Physical and
digital tools, and finally the fabrication process.
Our process
of exploration has relied on a nonlinear synthesis between information gathered
from models of different scales and mediums. Different weights of emphasis have
been placed on parts of the process depending on the gain and relevance of the
part under examination. The sequence of progression towards a viable solution
to the proposed problem is recursive, and iterates between what these
techniques have as results, of data to inform the research.
Cultural Centre as Public Space:
Architecturally, the building method of the
study lies in creating spatial fluidity.
The program of a Cultural Centre was worked out within the algorithm, which
calculates the building form. Force load distribution will then be optimised to
ensure these elements are in an equilibrium state. Program and circulation are
seen as input parameters for the generation process, adding an element of
pragmatism to the structures, along with immediate environmental conditions as
a driver for ecological building models. Design decisions that are based on
program, and pragmatic logic have been the result of the building process in
this case, in a sense working backwards in the classical design approach, where
the building method has been given a function that is generic to it.
Process:
Form finding has been used as a
modelling tool to structurally optimise formal explorations at the design
phase. Many architects, engineers and scholars have experimented with
translating the methods and geometries generated by form finding at the design
stage, to constructed edifices at full scale. The aim of the material
exploration of this research is to create a base of knowledge on the different
properties that concrete could inherit when used in different constructions
processes, and when paired with different constituents and composites. The material experiments are set as means to
produce articulate spaces composed of coherent building components.
Digital form-finding simulations aid in
numerically-quantifying the form finding processes, while embedding material
behaviour to output accurate formal results and structural analysis of the
forms produced. Enhancing the generation at the design phase, saving time and
effort while prototyping. A mesh relaxation algorithm was developed to simulate
the methods of forming to achieve a material informed simulation. The advantage
the current generation of designers has over previous attempts, carried by the
likes of Heinz Isler and Frei Otto, is the powerful computation that allows for
quantifying the geometries of qualitative forms achieved by physical models.
Hence allowing the accurate testing of these complex forms for per formative
criteria, whether structural or environmental.
Material Experiments:
Initial physical
models were carried out in fabric. The fabric is tensioned and following simple
logic of height and light informed spaces. The curvature of the forms evolved
in the process. The form indicates the natural force flow path in the geometry
but lacks stiffness. Inverting of the structure into a compressive shell seemed
a good solution. A mixture of plaster, water and glue is sprayed over the
fabric. The tensile structure is now coupled with the compressive properties of
the plaster.
Scaling up of the Prototypes:
The system in a
building scale was the goal. Different materials were tested for their
flexibility and stiffness. Concrete canvas, Jesmonite and Barchip fibre for
reinforcement are few of the emerging new materials that were tested. Each
material had its advantage and disadvantage. Few lacked stiffness while the
others lacked flexibility. A combination of these properties had to be tested.
Layering:
Studies on natural
systems revealed the fact that layering was the easiest process to achieve
structurally efficient forms. Few simple steps designed a material system.
1. Industrial fabric
is used for formfinding.
2. Jesmonite (a
cementitious composite) is sprayed over the fabric to keep the geometry in
equilibrium state.
3. A Doubly woven
steel mesh is laid over this form and Barchip fibre reinforced concrete is
sprayed over it to make the form structural. The thickness varies from 100mm to
150mm for a span varying from 15 to 25 metres.
Fabrication:
The tensioning of
fabric is done using hydraulic jacks and anchoring at edges. Jesmonite is
sprayed using robitic arms to maintain the uniformity in thickness. Similar
technique in used to sprayed structural concrete over the dry fabric and Jesmonite
layer.
This research has been
carried out at the Architectural Association School of Architecture In
fulfilment of an MArch degree at the Emergent Technologies and Design program
supervised by Michael Weinstock.
Riyad Joucka (MArch_AA) + Jack Chandy Francis (MArch AA)
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more information, please visit www.hybios.blogspot.com