A Detailed Visual & Critical Analysis of The Umlauftank 2 (UT2)

This report offers a detailed visual and critical analysis of the Umlauftank 2 (UT2), also known as the "Rosa Röhre," located in Berlin. Designed by architect Ludwig Leo, the UT2 is a significant example of modern architecture, serving as a research complex for water and naval architecture. The analysis covers the building's form, structure, function, materials, and unique style. The report examines how the architect integrated the building's function into its design, with the pink circulation tank being the most striking visual element. It also discusses the historical context, including its construction, use for shipbuilding research, and its current status as a protected monument. The report explores the building's construction using MS structural steel, corrugated sheets, and the absence of ornamental elements. Finally, it concludes by interpreting the building's design as a reflection of modern architectural principles and its significance within Berlin's cultural landscape.

VISUAL ANALYSIS PAPER
TOPIC:
A Detailed Visual & critical Analysis of
The Umlauftank 2 or UT2
Prepared By:
Mr. XXX
Instructor
Laura Martínez de Guereñu
Architecture History and Theory III – Modernism

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1. Introduction
Figure 1 The Unusual Building- UT2 in Berlin
 Building Name: Circulation tank 2, Umlauftank 2, or UT2, "Rosa Röhre"
 Location: Island in Tiergarden, Berlin Germany
 Architectural style: Modern
 Architect: Leo Ludwig
 Designed in Year: 1967
 Project Timeline: 1969 to 1974
 Recognition: The largest circulation and cavitation tank in the world.
The Umlauftank 2 is a research complex which was built by the Research Institute for
Water and Naval Architecture (Versuchsanstalt für Wasser- und Schiffsbau - VWS) at the
Technical University of Berlin. The Umlauftank 2 is the result of the last major construction
phase which lasted from 1969 to 1974. The "Rosa Röhre" was designed by Berlin architect
Ludwig Leo the UT2 was completed in 1974. This striking pink loop has a length of 120
meters and holds a water volume of 3300 tons.
The UT2 is the biggest circulation and cavitation tank on the planet and it's currently
a structure under Denkmalschutz. The structure was initially built for routine testing in
shipbuilding. It is not utilized for commercial activities but solely for research tasks of the
University (the Institute of Land and Sea Transport utilizes the circulation tank routinely)
About the Architect: Ludwig Leo (1924-2012) was a German designer. Regularly
refered to are his structure for the German Life Saving Society and the Circulation Tank.
Both are situated in Berlin and have just been conceded noteworthy landmark status. Leo
examined designing in Hamburg before coordinating the University of the Arts in Berlin
(Hochschule der Künste) to contemplate engineering. He finished his examinations in 1954.
From there on he worked with different surely understood German planners. In 1956 he

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opened his own studio in Berlin. In 1988, he was granted the German Critics' Prize.He is
often referred as the “Unusual Architect”.
2. Visual Analysis
On close observation of the historic structure & understanding the background of
construction, the preliminary visual analysis of the architecture can be presented as follows:
2.1.Form
Figure 2 The Building form is of a Ship
The architect Ludwig Leo has carefully understood the function of the structure and then
given it its form. He has studied all building utilities and created the external façade of the
structure in a wat the the “Form represents Function”. The building used in testing Ships is
designed in a Ship Analogy. The Umlauftank can be mistaken with an ocean liner stranded in the
middle of Berlin.
2.2. Structure
During the 1960s the "Umlauftank" - a cavitation tunnel to investigate hydrodynamics,
and make ecological and navigational building tests through scaled models of Ships - was too old
to fulfill the guidelines of the time and must be supplanted. Another tunnel must be fabricated.
This tunnel ended up being an enormous circuit pipe framework with a greatest measurement of
8 meters diameter. Water is siphoned through the circuit by two Diesel motors. Rather than
concealing the pipe behind a Facade Leo chose to highlight it - as it is building's primary

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function. The immense pipe is painted in pink and encases the primary structure giving it its
interesting outline.
Figure 3 During Construction
Figure 4 Structural Drawing/ Plan
The structure is made up of MS Structural steel sections and covered with a corrugated sheet
blue in colour.

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2.3. Function, Program or Use
This structure is used to test the flowability of ship parts. The main building houses a number of
water basins which can simulate different oceanic wave conditions. It contains the measuring
section, measuring instruments, controls and dashboards. the experiments can be prepared and
observed from a series of decks.
There are a Total of 5 Decks & the total height of structure is 30.8 meters and width is 54.250
meters.
Figure 5 Structural Elevation- The Great Pipe
2.4. Material & Technology
Leo has kept the building simple by using common mechanical & industrial construction
materials like MS Structural steel, pre-fabricated sections, Pipes, RCC Concrete etc.
The framed MS Structure was first constructed and then the Pipe installed in stages. The external
façade was installed at the last using corrugated blue sheets using large building cranes.
2.5. Ornamental Elements
No ornamental elements or intricate decorations
are observed in the structure. Since it is an educational

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or research building, the architect has rather chosen to keep the structure simple. The large Pink
Pipe only forms the main attraction.
2.6. Style
Figure 6 The unusual Building Style
The structure has its own unique & unusual style as per the modern & forward thinking
of the architect. Leo’s bold embrace of modernity and willingness to experiment are very present
in this work.
3. Final Interpretation
The Umlauftank 2 is a historic monument since 1996. In 2004 the research activities were
discontinued at the site as computer simulations are nowadays a more efficient means to conduct
this type of research. From 2014 to 2017, the building was restored as a historic monument on
behalf of the Wüstenrot Foundation. The building uses a “Function to Form” concept and is
shaped like a Ship floating on water. Its main use was to test the hydraulic behavior of boats &
ships in water. It is an unusual structure by an unusual modern architect. Pink tube forms the
water pipe, placed below and exposed to public. On top, a five-story blue aluminium building
with offices, labs is located, which is an unusual sight for a building of 1960s. Thus, the
architecture combines Industrial building, a scientific research center & a Machine. Leo planned
the Circulation tank as an antithesis to the egotist engineering of the national communists.
The architect has used simplicity & minimalism concepts of modern architecture and the
Pink color adds to the then Pop culture in Berlin.
4. References

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 Rosa Röhre, Wikipedia, 31 Jan. 2019, de.wikipedia.org/wiki/Rosa_Röhre.
 "Umlauftank 2 (Circulation Tank) ". 2019. Visitberlin.De.
https://www.visitberlin.de/en/umlauftank-2-circulation-tank.
 Umlauftank 2, Artifakt, 15 Mar. 2017, www.artefakt-berlin.de/en/current-
projects/2017/umlauftank-2-eng/.