Formworks Spring 2013: Formworks

With his suggestions for the use of tied reeds in the casting of concrete, Vitruvius may be one of the first people to ever describe a type of flexible 'fabric' formwork. Reed imprints found in the underground 15th-Century concrete vaulting of Villa Medici in Rome suggest that these flexible plants were indeed used to create a lightweight formwork that could be easily maneuvered in tight spaces.

Reed centring in the Roman concrete vaults beneath
Villa Medici, Rome. Reproduced by permission of Matthew Bronski. 1

It was not until the Industrial Revolution, however, that a true fabric formwork, as we know it today, first appeared. Attributed to German architect / builder/mason, Gustav Lilienthal, the method of pouring floors into suspended fabrics saved on centring, materials, and labor. Further, the geometries of fabric-formed concrete is more efficient--the catenary curves of the concrete follow the bending moments and also save around 20% of concrete needed in a beam.

Fabric formwork progressed quickly and was given a geotechnical application for hydraulic purposes in canals and embankments.

Ybarra Hotel Tres Islas (1972).

Reproduced by permission of Fundación Miguel Fisac. 2

20th-Century Spanish Architect Miguel Fisac was arguably one of the first people to acknowledge fabric formworks for its aesthetic qualities--not simply its structural, utilitarian functions. He created hollow, bone-like beam structures that turned away from wooden formwork surface patterning, and he did his best to express the tactile, plastic qualities of concrete. In some ways, Fisac's expression of the textile nature of the material within his facade panels is reminiscent of Frank Lloyd Wright's textile blocks, which ironically were not made using textiles, but rather complex rigid moulds. Still, the notion that a heavy, solid material could be used to express delicate, intricately patterned materials (and could do so in a light, modular way) was revolutionary.

Frank Lloyd Wright Textile Blocks. 3

Frank Lloyd Wright Textile Blocks Connection Details. 4

These are qualities with which designers have continued to experiment. The invention and mass-production of durable synthetic materials in the late 20th-Century changed the practice of fabric formworks in an extraordinary way. Kenzo Unno, Mark West, and Rick Fearn have each pushed the limits of concrete in aesthetic, technical/structural, and environmental ways. Aiming to have no material waste, and to enhance surface material quality have been driving goals. Further, experimentation surrounding structural optimization has shown that fabric formworks can not only produce voluptuous structures, but seemingly impossible thin forms as well.

CAST Truss, University of Manitoba. 5

SFMoMA - P_Wall (2009). 6

Additionally, the increasing use of parametric software and digital fabrication techniques has made it much easier to design and create dissimilar modular panels. Concrete must no longer be though of as a stiff, bleak medium of Modernism, but rather, as a malleable, exciting material to be constantly reinvented.