Natural Granules Aggregations

Based on research on natural aggregation undertaken by Frei Otto and his team at the Institute for Lightweight Structures in Stuttgart, and by Ralph A. Bagnold on the physics of blown sand and desert dunes, this research examined processes of sand formation for deployment in design. In nature such processes are observable in dune and ripple formations shaped by airflow and water, moreover, the interaction between aggregate and environment. Initial experiments focused on sand pouring and draining formations. Variables included amount of sand, pouring speed, funnel size for pouring or draining, the angle and roughness of the receiving surface and extrinsic influences such as gravity and airflow. Subsequently geometrically differentiated lattice structures were introduced to study their impact on pattern formation, in relation to the inclination, orientation and distance between lattice members and distribution and sizes of openings. Wind-blown sand in part drained through layered lattices resulted in aggregate formations on and below the lattice datum, where sand got captured, resulting in terrains of varied topography and texture, cavernous spaces, and different degrees of exposure to extrinsic influences. The orientation of sand formations relative to prevailing wind directions is significant with regards to the further formative process and the sun-path is of importance with regard to thermal performance and self-shading. A desired relation between aggregate and prevailing wind direction and sun-path can inform the placement of specifically articulated lattices and therefore the distribution of specific aggregation pattern. Additionally the closure of drain channels can be achieved locally through small pneumatic cushions that shut off single lattice fields to prevent sand passing through.

AA Diploma Unit 4 (Michael Hensel, Achim Menges)
Gen Takahashi, Architectural Association, London, 2005-06