Façade engineering meets ornamentation
Visualization: emptyform, Darmstadt, Germany. Photo credit: KSP Jürgen Engel Architekten
The third-largest mosque in the world is currently under design on the bay of
Algiers. It has about 95,000 square meters of natural stone façade, boasts the
highest minaret in the world, a dome of 50 meters diameter, and a Prayer Hall in
which 35,000 worshippers can gather. The complex – which is expected to attract
120,000 visitors a day – is impressive in many respects. The project represents
a unique challenge for the façade consultants from DS-Plan. They are supporting
a joint venture consisting of Jürgen Engel Architekten and the engineering
consultancy Krebs und Kiefer with the design of the façades. In addition to the
technical implementation, the historical, religious and esthetic aspects of the
task make it a special challenge. For example, it was necessary to develop
solutions that would allow traditional filigree Islamic ornamentation to be
incorporated without delaying the project.
Visualization: emptyform, Darmstadt, Germany. Photo credit: KSP Jürgen Engel Architekten
The most striking structure in the mosque complex, which was commissioned by
the Algerian state, is without doubt the 264-meter minaret. The challenge for
the architects is to face the outside of the tower with traditional Islamic
filigree ornamentation while ensuring that the tower still has a sturdy
appearance and is capable of withstanding external influences such as
earthquakes and the extreme climate. The traditional carving of a façade made of
natural stone – as traditionally worked with hammer and chisel – would, however,
take several decades. The solution to the problem is a combination of technical
expertise and elements from traditional Arab architecture.
The minaret: Fiber concrete instead of hammer and chisel
The Islamic ornamentation is being integrated into the façade by means of so-called
mashrabiya. These are decorative wooden screens used in Arab tradition as
windows providing solar protection, daylighting, ventilation and privacy. To
allow the complex and detailed designs to be completed efficiently and within
the scheduled construction period, the DS-Plan façade experts have developed an
up to date method: The mashrabiya are prefabricated using fibre-reinforced
precast concrete, an extremely robust and lightweight material. These artistic
panels will clad an area of 7,300 square meters on the minaret alone, with a
total area of 15,160 square meters being applied throughout the complex.
Visualization: Macina, Hannover, Germany. Photo credit: KSP Jürgen Engel Architekten
On the minaret, the mashrabiya elements will act as an external screen one
meter in front of the 5.85-meter storey-height semi-unitized double façade. The
space between the suspended natural stone panels and the four symmetrically
arranged concrete cores of the tower is up to 80 centimeters. The new connection
methodology of the façade elements and their substructure, especially developed
for an earthquake zone taking these unusual façade design requirements into
account. In this way, the esthetic requirement to decorate the façade with
Islamic mashrabiya elements designed to exact specifications is met with
state-of-the-art technology.
The mosque complex: Huge amounts of natural stone
In addition to fibre-reinforced concrete specified by DS-Plan’s façade
specialists for the minaret and some parts of buildings, the main façade
material used throughout the mosque complex is natural stone – with a total area
of some 95,000 square meters. It is intended to maximize use of local, durable
materials and to use local companies and semi-skilled workers wherever possible.
A mosque on this scale is designed just once every millennium. The entire
complex will have a gross floor area of some 440,000 square meters. The minaret,
visible from afar, will house a museum of Islamic history, sky lobbies, a
research center, and two viewing platforms. The complex also has a Prayer Hall,
the central mosque park, a cultural center, a library, a boarding school, and
many other facilities.
Visualization: Macina, Hannover, Germany. Photo credit: KSP Jürgen Engel Architekten
The Prayer Hall: A dome 70 meters high
The DS-Plan façade engineers are working on six buildings and always have to
bear in mind the harsh climatic conditions such as relative humidity, the high
salt content of the air, wind, and high temperatures. The specialists have also
been closely involved with the Prayer Hall, which has a capacity of 35,000
worshippers. The dome, which soars to a height of 70 meters, also features the
traditional mashrabiya elements. Here they are integrated in a unique manner in
the Arab world: They are attached to the outside of the thermal shell of the
dome like ribs, giving the impression of being an external support structure.
The actual substructure, however is internal. Sunlight reflected into the dome –
and which can be directed with a system of mirrors – creates a special ambience.
Further Information:
Drees & Sommer AG
Untere Waldplätze 28
70569 Stuttgart • Germany
Tel.: +49 711 1317-0
eMail: info@dreso.com
web:
www.dreso.com
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