Friday, October 28, 2011

Temporary Pavillion Structures (2)

Eco-Friendly Pavilion From 2000 Recycled Beer Crates
Eco-friendly architecture design becoming a trend or designers are really into saving the environment. More and more designers and student designers are now into eco-friendly design and this include the students from the University of Applied Science in Detmold, Germany who had just recently designed the Boxel pavilion.
This hailed as eco-friendly pavilion is made out of 2,000 beer crates. As part of the students’ course, they are required to develop structures from computer modeling to construction; the Boxel Pavilion is made that resulted into being the coolest music venue in the campus.

You might wonder why this structure is hailed eco-friendly, it is because, the beer crates are recycled old beer crates donated by a local brewery. Eco-friendly architecture is in vogue around the world with innovative building materials cropping up. Turning beer crate into building is sure an eye-popper.
The temporary construction was designed using parametric software to control the position of the boxes in relation to the overall geometry and to analyse the structural performance.Several static load tests were made to understand the structural behaviour of the unusual building material. In parallel to a series of shearing and bending tests in the university’s laboratory of material research, the structural concept was simulated and optimised using FEM-Software.
Finally, a simple system of slats and screws was chosen for the assembly of the pavilion that allowed for a flexible and invisible connection. Additional bracings were placed in the upper part of the boxes to generate the required stiffness of the modules. The structural load transfer was realised by concrete-lined boxes at the three base points that served as foundation for the pavilion. The beer crates are recycled old beer crates donated by a local brewery. Though temporary in nature, the structure reminds us of applying imagination to turn a host of daily use items into architectural wonders.

ICD/ITKE Research Pavilion 2010
In 2010, the Institute for Computational Design (ICD) and the Institute of Building Structures and Structural Design (ITKE) designed and constructed a temporary research pavilion.

Any material construct can be considered as resulting from a system of internal and external pressures and constraints. Its physical form is determined by these pressures. However, in architecture, digital design processes are rarely able to reflect these intricate relations.
The innovative structure demonstrates the latest developments in material-oriented computational design, simulation, and production processes in architecture. The result is a bending-active structure made entirely of extremely thin, elastically-bent plywood strips.
Whereas in the physical world material form is always inseparably connected to external forces, in the virtual processes of computational design form and force are usually treated as separate entities, as they are divided into processes of geometric form generation and subsequent simulation based on specific material properties.
The research pavilion demonstrates an alternative approach to computational design: here, the computational generation of form is directly driven and informed by physical behavior and material characteristics. The structure is entirely based on the elastic bending behavior of birch plywood strips.
In order to prevent local points of concentrated bending moments, the locations of the connection points between strips needs to change along the structure, resulting in 80 different strip patterns constructed from more than 500 geometrically unique parts.

The strips are robotically manufactured as planar elements, and subsequently connected so that elastically bent and tensioned regions alternate along their length. The force that is locally stored in each bent region of the strip, and maintained by the corresponding tensioned region of the neighboring strip, greatly increases the structural capacity of the system.
The combination of both the stored energy resulting from the elastic bending during the construction process and the morphological differentiation of the joint locations enables a very lightweight system. The entire structure, with a diameter of more than twelve meters, can be constructed using only 6.5 millimeter thin birch plywood sheets.

The computational design model is based on embedding the relevant material behavioral features in parametric principles. These parametric dependencies were defined through a large number of physical experiments focusing on the measurement of deflections of elastically bent thin plywood strips.

Based on 6400 lines of code one integral computational process derives all relevant geometric information and directly outputs the data required for both the structural analysis model and the manufacturing with a 6-axis industrial robot.
The structural analysis model is based on a FEM simulation. In order to simulate the intricate equilibrium of locally stored energy resulting from the bending of each element, the model needs to begin with the planar distribution of the 80 strips, followed by simulating the elastic bending and subsequent coupling of the strips.

The detailed structural calculations, which are based on a specifically modeled mesh topology that reflects the unique characteristics of the built prototype, also allows for understanding the internal stresses that occur due to the bending of the material in relation to external forces such as wind and snow loads, a very distinct aspect of calculating lightweight structures.
Comparing the generative computational design process with the FEM simulation and the exact measurement of the geometry that the material computed on site demonstrates that the suggested integration of design computation and materialization is a feasible proposition.

ICD/ITKE Research Pavilion 2011
In summer 2011 the Institute for Computational Design (ICD) and the Institute of Building Structures and Structural Design (ITKE), together with students at the University of Stuttgart have realized a temporary, bionic research pavilion made of wood at the intersection of teaching and research.

The project explores the architectural transfer of biological principles of the sea urchin’s plate skeleton morphology by means of novel computer-based design and simulation methods, along with computer-controlled manufacturing methods for its building implementation.

A particular innovation consists in the possibility of effectively extending the recognized bionic principles and related performance to a range of different geometries through computational processes, which is demonstrated by the fact that the complex morphology of the pavilion could be built exclusively with extremely thin sheets of plywood (6.5 mm).
The project aims at integrating the performative capacity of biological structures into architectural design and at testing the resulting spatial and structural material-systems in full scale. The focus was set on the development of a modular system which allows a high degree of adaptability and performance due to the geometric differentiation of its plate components and robotically fabricated finger joints.
During the analysis of different biological structures, the plate skeleton morphology of the sand dollar, a sub-species of the sea urchin (Echinoidea), became of particular interest and subsequently provided the basic principles of the bionic structure that was realized. The skeletal shell of the sand dollar is a modular system of polygonal plates, which are linked together at the edges by finger-like calcite protrusions.
High load bearing capacity is achieved by the particular geometric arrangement of the plates and their joining system. Therefore, the sand dollar serves as a most fitting model for shells made of prefabricated elements. Similarly, the traditional finger-joints typically used in carpentry as connection elements, can be seen as the technical equivalent of the sand dollar’s calcite protrusions.
Following the analysis of the sand dollar, the morphology of its plate structure was integrated in the design of a pavilion. Three plate edges always meet together at just one point, a principle which enables the transmission of normal and shear forces but no bending moments between the joints, thus resulting in a bending bearing but yet deformable structure.
Unlike traditional lightweight construction, which can only be applied to load optimized shapes, this new design principle can be applied to a wide range of custom geometry. The high lightweight potential of this approach is evident as the pavilion that could be built out of 6.5 mm thin sheets of plywood only, despite its considerable size. Therefore it even needed anchoring to the ground to resist wind suction loads.

A requirement for the design, development and realization of the complex morphology of the pavilion is a closed, digital information loop between the project’s model, finite element simulations and computer numeric machine control.

Form finding and structural design are closely interlinked. An optimized data exchange scheme made it possible to repeatedly read the complex geometry into a finite element program to analyze and modify the critical points of the model.

In parallel, the glued and bolted joints were tested experimentally and the results included in the structural calculations. The plates and finger joints of each cell were produced with the university’s robotic fabrication system.

Employing custom programmed routines the computational model provided the basis for the automatic generation of the machine code (NC-Code) for the control of an industrial seven-axis robot. This enabled the economical production of more than 850 geometrically different components, as well as more than 100,000 finger joints freely arranged in space.

Following the robotic production, the plywood panels were joined together to form the cells. The assembly of the prefabricated modules was carried out at the city campus of the University of Stuttgart. All design, research, fabrication and construction work were carried out jointly by students and faculty researchers.
The research pavilion offered the opportunity to investigate methods of modular bionic construction using freeform surfaces representing different geometric characteristics while developing two distinct spatial entities: one large interior space with a porous inner layer and a big opening, facing the public square between the University’s buildings, and a smaller interstitial space enveloped between the two layers that exhibits the constructive logic of the double layer shell.

1 comment:

  1. Great blog, keeping me from working. All the Best