Current enthusiasm for convoluted masonry shells emerges from our centuries old fascination with funicular form-finding and a widespread desire to employ – or be employed by – the latest in software. As it turns out, these so-called free forms are bound by engineering assumptions that are not entirely rational. This talk explains why Hooke’s insight into the catenary arch doesn’t really apply to masonry domes, and shows how a more rational structural theory can produce counter-intuitive results. Examples anticipated in the theory and practice of masonry structures include the anticlastic or bell-shaped pseudome, the eponymous conedome, and the completely flat floordome, all of which would fail utterly as arches. Examples apparently without precedent in the history of building include the antidome, which descends from its abutment ring to form a bowl, and the ambidome, which rises conventionally from a tensile hoop to a circular crown, from which it descends to a pendant oculus.
Why pursue such oddball forms?
1. Some of them perform better than their “form-found” or mathematically “optimized” counterparts.
2. In parts of the world where labour needs employment and where tensile materials are expensive, a better understanding of masonry is of immediate human value. (Particularly when there is also seismic risk.)
3. Even in more industrialized economies where masonry domes are little more than curiosities, testing the assumptions on which we base our structural design work can only be healthy.
4. Limited durability of affordable tensile reinforcements is compromising our civil infrastructure, so compression-intensive techniques are of inherent economic interest.
This talk sketches out recent results achieved by Emanuel and his team and closes with some of the open questions he’ll be investigating at C.A.S.T.
Emanuel began architecture studies at Cornell in 1978 and eventually earned an M.Arch with distinction from Dal in 1998. Between, before, during and since he has contrived and built many kinds of things, including high-rise formwork, yacht interiors, special effects machinery, some underwater projects, several gallery exhibits, and many film sets, as well as more conventional buildings and cabinets. He has contributed to numerous award winning architectural projects, whether within an office, as design subcontractor, as consultant, or as builder. Most of his own design practice has been as production designer or art director on several dozen films (shot in Argentina and Italy as well as in Canada) many of which have received national awards and nominations. He has lectured and taught in seven provinces and four continents, and published on geometry, craft, pedagogy, and material heritage, as well as construction management and structural design.
Since 2007 he has been teaching full time at the Dalhousie University School of Architecture, where he is now senior instructor.
Food for Thought
Tuesday, February 7, 2017
12PM | Centre Space
John A. Russell Building
Faculty of Architecture
University of Manitoba