The architecture of phase change at McGill

Abstract

Montreal has a history of monumental ice construction dating back to 1885 when the first large-scale ice palace was constructed for the winter carnival. At McGill University, we have experimented with large-scale ice construction since 1972. In addition to the use of traditional ice blocks, we have built composite structures using suspended nylon fabric as a substrate for depositing vaporized water in the freezing winter conditions. Our largest structure was a scale model of the Pantheon, built with snow, and spanning 34 ft. Robotic CNC and rapid prototyping (RP) methods are opening up new horizons for the water-to-ice phase change process in architecture. Since 2006, we have been working at three different scales in this field, funded by a 3 year $174 000 SSHRC grant. A small Fab@Home rapid prototyping machine has been modified to make small 3D ice objects in a -20°C environment. One scale up, we are now working with an Adept Cobra 600 robot, producing very finely detailed 3D ice objects up to 30 cm across and 20 cm high. Both these machines are controlled by a personal computer and rely on a water delivery system with micro-valves, adapted for the purpose. The different melting temperatures of brine and pure water make it possible to use brine as scaffolding for the ice model, since the frozen brine can be melted away at a lower temperature than the ice. In 2010, we hope to scale up again, this time to the architectural scale with a new Macro robot.