Today, we talk of reusing and not demolishing buildings to reduce carbon emissions, and yet of course it is an older idea. A classic example from the late-1970s is the Herrera and Obes Warehouse in Montevideo’s docks.
An old 19th-century brick warehouse had been gutted by fire, and designs were invited for a new building. However, the Uruguayan engineer Eliado Dieste won by applying a different strategy. Instead his far cheaper method retained and reinforced the warehouse’s perimeter walls. Dieste inserted pre-tensioned concrete columns bonded into these existing brick walls to support two edge beams running at roof level along the longer dimension. Externally, he wrapped the building with another brick skin, while internally a dramatically rippling 45-metre-span gaussian-vault roof soared across the 4,200-square-metre warehouse.
Dieste’s gaussian-vault system is,in simplest terms, a series of inverted catenary beams with double-curvature within them to provide rigidity against buckling. There are 14 of these shallow arched beams forming the new roof for the Herrera and Obes Warehouse. The beauty of the system is that the weight of the gaussian vaults can be reduced to put less load onto the edge beams and columns below. Indeed, the roof vaults are only 120mm thick, and of that 100mm is hollow bricks underneath a 20mm concrete covering layer with intrinsic pre-tensioned rods: the uppermost surface of the concrete is then painted white to reflect solar radiation. Another benefit of having a series of gaussian vaults is that each can be curved asymmetrically to create small steps in-between, such that bands of vertical glazing are inserted to admit daylight. Furthermore, the roof vaults can be erected individually using an ingenious stepped scaffolding arrangement that was then shifted sideways to build the next vault.
Eliado Dieste was one of the seminal 20th-century engineers along with Pier Luigi Nervi and Felix Candela – but unlike them, his projects were almost always in brick as he regarded that more appropriate for South America’s economics and resources. Nonetheless, his work aimed equally high,with Dieste declaring of his overtly aesthetic sensibility: ‘There is nothing more noble and elegant than to resist [forces] through form’.
