Architectural students at the Tokyo University of Science developed an experimental, extremely lightweight, load-bearing structure for a temporary pavilion. The 26-metre-long, up to 7,5-metre-wide and 4,25-metre-high volume is self-supporting and comprises only two kinds of component: the metal bearing elements and a delicate space-enclosing skin consisting of an 0,7-mm membrane of elastic polyester fabric. The membrane is drawn over metal tubes that create a tensegrity system and forms the tension element. The 131 compression bars are 25-mm diameter aluminum tubes of various lengths and there is no contact between them; instead, they are connected to the skin by sliding the ends into sheaths sewn on. The membrane is anchored at the base like a conventional tent with pegs consisting of aluminum tubes with tips pressed together to form a point. The compression members are pushed into these pegs and fixed in position by means of steel pins. With a weight of only 600 kg, this airy structure covers a ground area of 146 square meters. The pavilion was erected by 70 students in a single day. Initially, they laid out the ready tailored skin, then slid the tubular members into the sheaths. The overall structure was tensioned on all sides, pushed upwards at the same time in the interior and finally fixed to the ground. The convex and concave forms resulting from this create an animated surface and a lively interplay of light and shade. Since the membrane screens off 80% of the UV radiation, but allows 50% of the daylight to pass through, the softly filtered light creates a fascinating spatial impression internally. When illuminated, the translucent pavilion has the appearance of a lighted sculpture.
In reference to economy of materials, rapid deployment, self sufficiency, interactivity and leave no trace aspects of the ten day Burning Man Festival in the Nevada desert I have explored vacuumatically prestressed structures (vacuumatics) to create a temporary structure.
Using minimal materials, a Balloonwrap cloud would encourage maximum participation during the construction and throughout the festival. An ephemeral soft cloud like landscape, where participants delight in modifying the shape as well as being able to interact with the structure by lying down, dancing on, climbing and sitting inside the enclosure.
As documented in the film above, Balloonwrap is a vacuumatic structure made using Polythene sheets at 63 microns, 5m x 3.65m, with balloons as the filling. A large scale model here is made rigid enough to span gaps, flexible enough to bend back on itself and strong enough to act as a seat or even a bed.
The material could therefore be used as the floor, wall, roof and seating elements in a continuous loop for any installation with the added benefit that it would have good thermal insulation as well as solar reflective potential (using silver/white reflective balloons/opaque film).
The main advantages of Balloonwrap are form flexibility and adaptability. An important factor that determines its adaptability is the flexibility control. Without any negative pressure (0% vacuum) the balloons inside the polythene enclosure possess hardly any consistency and are able to flow freely inside this skin. By increasing the amount of vacuum pressure the consistency of the balloons gradually increases, resulting in a more or less plastic behaviour of the structure. This enables the structure to be shaped while keeping its newly given form. Finally, in fully deflated state (100% vacuum) the Balloonwrap becomes rigid, with balloons used as a filling in my experiments, it is possible to climb the rigid load-bearing structure and sit comfortably! The reversibility of this rigidifying process enables the Balloonwrap to be re-shaped all over again.