A FAESABLE WAY TO MAKE FREEFORM SHELL STRUCTURES.

Researching the reconstruction of the Philips Pavilion, we described a way to make the anticlastic forms of the pavilion by spraying shotcrete against a pre-stressed membrane mould [5]. Sinclastic forms can be made with inflatables [1]. Binni shell, Monolithic-dome and Solid-house are organisations using inflatable moulds to make domes. It is possible to combine inflatable’s with pre-stressed membranes to make “free-formed ” surfaces that are sinclastic and anticlastic. To elaborate the possibilities, columns, cables, and beams can be added. Columnspushing the membrane will introduce high points, cables pulling the membrane will introduce low points. The introduction of stiff, bent beams will influence the form of the surface as well as the cable structure covering the membrane. The membrane can be manipulated in 4 different way’s.-anticlastic by a prestressed membrane-sinclastic by an inflatable membrane-high points by columns / low points by cables-arches, beams or cables pushing or pulling the membrane can be used to make (curved) lines. The behaviour of “Free form ” surfaces made out of manipulated membranes is difficult to modulate. The behaviour of cable-nets allows more freedom in the making of patterns. Therefore we replaced the presstresed membrane by a cable net. The cable net will make the form of the surface and is manipulated by inflatable’s cables and columns. The net structure is covered with a finer grid and rigidised with shotcrete. To prove this we made a small blob structure. The paper will describe the experiments with the cable nets and the making of the small blob structure. It is possible to make al kind of free formed shapes with standardized inflatable’s in combination with standard cablenets. The researchers have applied for a patent on this method that leads to a feasible way for making “FreeForm-shellstructures”