RUDN University professor brought together disparate information about metal membrane suspended roofs, that allow designing buildings with large spans. These structures are used in the construction of sports complexes, airports and some other buildings. An op-ed article was published in Thin-Walled Structures.
“Metal membranes are used much less often than other types of suspended roofs (among which one can distinguish awning or mesh metal structures, sheaths of glued wood). It is interesting that Russia has an unconditional priority in this type of constructions: they were first used abroad only 35 years later in the US, when they were developed by architect Vladimir Shukhov for 4 pavilions at the All-Russia industrial and art exhibition in Nizhny Novgorod”, Head of the Department of Strength of Materials and Structures of RUDN University Sergey Krivoshapko said.
Metal membrane suspended roofs are spatial constructions of thin metal sheet, which is only a few millimeters thick, and rigid support contour. They can be compared with a soap pellicle formed after immersion of a wire ring into a diluted dishwashing liquid. Just like a bubble, which is blown out of the contour, a metal membrane can have different curvatures.
In fact, the shape of the design, more precisely, of its middle part, is determined by the geometry of the frame to which it is mounted and by the presence of weighting agents. Thanks to them, it is possible to create a membrane in the form of a paraboloid, cone or sphere. Spans with metal membrane roofing can reach hundreds of square meters. For example, the universal stadium at Mira Avenue measuring 224×183 m, which was the largest building of the 1980 Olympics, is roofed by a 5 mm thick sagging membrane.
The structure only seems to be fragile: the technology involves complex engineering calculations that take into account the climate, metal used for the construction, as well as load created both by the weight of the membrane itself and by falling snow. From a technical point of view, the advantage of metal membranes is that they allow to significantly reduce the weight of the structure, its cost (up to 60%) and material consumption (for steel up to 70%). Moreover, the structure itself implies combination of bearing and enclosing functions in one material.
“Design features of metal membrane suspended roofs determine their cost-effectiveness. Although nowadays almost all the problematic issues concerning the design, manufacturing, installation and operation of metal membranes are theoretically solved, few design bureaus and organizations are ready to take up work. The study of the preconditions for the appearance of functional solutions in construction, the history of development and the improvement of construction technologies will allow us to summarize the experiences accumulated over decades and issue a fundamentally new solution. Otherwise, architects and engineers will have to replicate what has already been achieved in construction and architecture”, Sergey Krivoshapko said.