Above: Urban Dunes project used 3D printed sandstone to create the microclimatic space/Image Source: Barberio Colella Architetti
Barberio Colella Architetti, the Italian design firm joined forces with Architect Angelo Figliola to create unique Urban Dunes project to reduce the heat island effect for an extreme climate like Abu Dhabi using 3D printed sandstone.
The climate of Abu Dhabi is hostile to normal external activities and this makes the project all the more interesting.
URBAN DUNES PROJECT
For the Urban Dunes project both the design experts worked on an elaborate design idea that originated from their in-depth awareness of the climatic context of Abu Dhabi’s and Emirates’ traditional architecture, such as elegant vaulted spaces, vernacular shading devices, and cold-water basins.
The Urban Dunes project experts wanted to emulate UAE’s traditional architecture using the locally available sand so that the desired effect of creating an urban “Oasis” would be achieved. This was possible only by lifting a thick layer of sand overhead which mixes passive and low-tech active systems to maximize the outdoor thermal comfort calculated with the UTCI index.
But such a manufacturing feat is not easily achieved. Thus the project team resorted to 3D printing technology. The technology is now more increasingly used for construction and with its capability to manufacture complex shapes makes it an ideal choice.
URBAN DUNES PROJECT WITH 3D PRINTED SANDSTONE
The vault is composed of several stereotomic blocks made of 3D printed sandstone, using the local sand as a primary material. The sand is made solid by using the binder jetting technology, which is capable of fabricating big blocks with a high level of precision. The use of a 3D printed vault with a thickness of 55 cm, permits to avoid the overheating of the urban space thanks to the high thermal mass of the shell, acting as a main passive strategy.
The sand is mixed with a heat reflective cool pigments to increase surface reflectance and to reduce surface heat build-up, thus reducing energy consumption through lower cooling requirements. The space below the 3D printed sandstone vault represents an urban microclimatic space protected from the sun using a vernacular sun shading device, the mashrabiyya, which also enhance the natural ventilation of the space. In fact, the wind meets the perforated surface of the mashrabiyya and increases its speed due to the Venturi effect. This incoming airflow meets and touches cold water basins, spreading a sense of freshness inside the public space.
Besides, the space under the shell is also naturally ventilated with the use of a low-tech system as the earth pipes and four mini wind catchers are placed by following the CFD analysis.
Above: 3D printed sandstone vault in Abu Dhabi/Video Source: Barberio Colella Architetti/YouTube
Moreover, the surrounding palm trees, close presence of two waterfall fountains and the natural traditional ventilation of the space gives out a refreshing sensation, psychologically reinforced by the sight of the flowing water.
The Urban Dunes project features also two active systems to maximize cooling efforts. On the one hand, a high-pressure misting system is used to reduce significantly the surrounding air temperature (up to – 20 °C) by forcing water via a high-pressure pump producing a micro-fine mist. On the other hand, the shell is cooled through a network of tubing through which flows a cooling fluid. The constant temperature of the earth can be utilized to passively cool the fluid. By mixing those systems it is possible to reach a UTCI of 26 °C for August (the warmest month in Abu Dhabi) that represents a comfortable thermal perception for an outdoor space.