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Largest Brick Structure in the World: Jetavanaramaya Tharindu Ishan Edirisinghe UNMC 009966
1. INTRODUCTION
Jetavanaramaya (also known as Jetavana) was built by King Mahasena in 273-301 AD. Situated in
the ancient city of Anuradhapura, which was the capital of Sri Lanka during that era. At the time of
its inception, Jetavana was appreciated as the third tallest structure in the world followed by the
Great Pyramids of Giza. Jetavana currently has a Volume of 233,000 cubic meters, which inarguably
makes it the largest brick structure in the world. In 1985 Jetavana was named a World Heritage Site
by UNESCO.
After its construction, Jetavana stood at 121.9m (400ft). At present, Jetavana stands at 70.7m with a
base diameter of 102m. It is a brick stupa, where more than 93,300,000 baked bricks have been
used for its construction (Ranaweera, 2004).
1.1. Back Ground
Jetavana is a religious monument built to honour the Eight Great Deeds of Lord Buddha and to
enshrine the possessions of Lord Buddha. Jetavana is said to enshrine a sash or belt tie which
belonged to Lord Buddha.
Construction of a stupa is believed to be a great deed in Buddhism; hence countless number of
Kings in ancient Sri Lanka built stupas to accumulate good Kamma. Furthermore, the presence of a
stupa gives one a feeling of stability, strength, nobility, and grandeur (Ranaweera, 2004)..
Figure 1 Jetavanaramaya Stupa.
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Source: De Silva, 2010
Largest Brick Structure in the World: Jetavanaramaya Tharindu Ishan Edirisinghe UNMC 009966
2. DESIGN
Jetavana is a solid construction, mostly composing of burnt bricks.
2.1. Components
The design of the stupa can be broken down into 9 main components. Figure 2 shows the basic
components of a Sri Lankan stupa.
Figure 2. Main components of a Sri Lankan stupa.
Source: Ranaweera & Silva, 2006, fig. 10
The dome is the largest and structurally the most important component of the Jetavana. There are
many different dome shapes used for stupas such as; bell, bubble, paddy, pot & lotus. In the case of
Jetavana, the paddy heap shape was adopted. This dome shape is geometrically similar to an
ellipsoid.
The basal rings, square chamber, cylinder and spire are all made of different sizes of burnt bricks,
made specifically for each component of the stupa.
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Main Components of a Stupa
1, 2, 3 - Basal rings
4 - Dome
5 - Square Chamber
6 - Cylinder
7 - Spire
8 - Minaret
9 - Crystal
Largest Brick Structure in the World: Jetavanaramaya Tharindu Ishan Edirisinghe UNMC 009966
2.2. Foundation
Like all mega stupas, the location of Jetavana was carefully chosen so that the bed rock was situated
close to the surface. In the case of Jetavana, the foundation extends 8.5m (28ft) to the bed rock (W.
Geiger, 1950).
No accountable source of the foundation constructions of Jetavana exists. However, the Mahavamsa
a chronicle that records the history of Sri Lanka contains a description of, construction of a
foundation of a mega stupa similar to Jetavana, called Ruvanvelisaya.
This account states that initially the proposed land was dug out to the bedrock. Then crushed rocks
were carried in to fill the space and were compacted by elephants, whose legs were covered with
leather. Afterwards, butter clay was used to fill in and level out the surface of crushed rock. This is
followed by a course of bricks placed on top of the clay. Over this, a layer of lime paste was
reinforced by a network of iron. The last layer was sheets of copper and silver for water proofing
(W. Geiger, 1950). The end product was a reinforced concrete foundation with water proofing. This
foundation method might have been used for the construction of the Jetavana foundation, as
Ruvanvelisaya was constructed 100 years prior to the construction of Jetavana.
3. MATERIALS
Also according to Mahavamsa there was firm quality control on materials used by the ancient
builders.
3.1. Bricks
The bricks used in the construction of Jetavana had much better strength and a larger size relative
to modern factory made bricks in Sri Lanka. The properties of the bricks used in Jetavana are given
in table 1.
Table 1. Mechanical properties of Jetavana bricks.
Property Value
Compressive strength 8500 kPa
Tensile strength 850 kPa
Young’s modulus 4.5 GPa
Poisson’s ratio 0.25
Specific weight 16.9 kN/m3
3Source: Ranaweera, 2004, Table 4
Largest Brick Structure in the World: Jetavanaramaya Tharindu Ishan Edirisinghe UNMC 009966
There were different sized bricks used. This was because various sizes of bricks had to be used for
different parts of the stupa.
3.2. Mortar
An analysis done by Abeyratne (Ranaweera, 2004) on the mortar in Jetavana, revealed that the
mortar consisted of finely crushed dolomitic lime & sand and clay in a ratio 1:5. The role of mortar
was primarily to fill the gaps in between the bricks. Therefore, a thin mortar of slurry consistency
was used in the construction.
3.3. Brickwork
Given that the mortar was of thin consistency, the mortar layer was close to zero. This made better
transfer of load between the bricks, virtually by direct contact.
3.4. Plastering
A final layer of plaster was used on the outer surface of the brickwork to provide water-proofing for
the stupa.
Figure 3. Ancient brick work of Jetavana Stupa.
Source: Ranaweera, 2004, fig. 16
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Largest Brick Structure in the World: Jetavanaramaya Tharindu Ishan Edirisinghe UNMC 009966
4. CONSTRUCTION PROCESS
The design of a stupa is far more complicated than that of a pyramid. Thus, builders who worked on
Jetavana showed great technological skills and management skills. The site was well supervised and
quality control was a major priority for the builders. Mahavamsa gives a description of,
construction of colossal stupas similar to that of Jetavana. (W. Geiger, 1950)
5. STRUCTURAL ASPECTS
According to Prof. M.P.Ranaweera, Department of Civil Engineering, University of Peradeniya, the
paddy heap shape of Jetavana was ideal in terms of the structural perspective. This is due to the
gradient of the paddy heap being equal to the angle of repose. This in turn creates very low tension
in the dome due to self-weight (Ranaweera & Silva, 2006). According to many, ancient builders have
discovered this shape from trial and error.
A Finite Element studies done by Prof. Ranaweera on Jetavana, showed that a maximum vertically
compressive stress of 837kPa exists at the centre of the stupa at foundation level. This compressive
stress is 1/10 of the maximum strength of the brick. In addition, the hoop and radial stress are
compressive with a maximum stress of 208 kPa (Ranaweera, 2004).
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Largest Brick Structure in the World: Jetavanaramaya Tharindu Ishan Edirisinghe UNMC 009966
6. CONCLUSION
Due to the strict quality control of construction material & construction management, Jetavana was
able to earn the title of the largest brick structure in the world during the time of its construction.
Even in the present (after conservation program), this stupa stands as the largest brick structure in
the world.
Figure 4 Jetavanaramaya in the 1880-1890.
Figure 5 Jetavanaramaya in the 2010
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Source: Loroj. Anuradhapura Jetavanaramaya. 2010
Source: Jetavanaramaya Dagoba Ruined. 2009
Largest Brick Structure in the World: Jetavanaramaya Tharindu Ishan Edirisinghe UNMC 009966
7. LIST OF REFERENCES
Ranaweera, M.P, Ancient stupas in Sri Lanka – Largest brick structures in the world. 2004. CHS
Newsletter No. 70, December 2004, London, Construction History Society. Web. 1 Nov. 2011. <
http://www.stupa.org.nz/imagine/CHSPaper.pdf >.
Ranaweera, Munidasa, and Silva, Gamunu, Conservation And Restoration Of Ancient Stupas In Sri
Lanka. 2006. Proc. of Tenth East Asia-Pacific Conference on Structural Engineering & Construction –
EASEC10, Bangkok, Thailand. Bangkok, 2006. Web. 3 Nov. 2011.
<www.stupa.org.nz/imagine/Ancient_Stupas_in_Sri_Lanka.pdf>.
Pieris, Kamalika. Architecture and Landscape in Ancient and Medieval Lanka. Web log
post. Lankalibrary. 25 June 2006. Web. 04 Nov. 2011.
<http://www.lankalibrary.com/phpBB/viewtopic.php?f=19>.
Pieris, Kamalika. Engineering skills in ancient and medieval Sri Lanka. Web log post. Lankalibrary. 24
Dec. 2008. Web. 04 Nov. 2011. <http://www.lankalibrary.com/phpBB/viewtopic.php?
f=19&t=4568>.
W. Geiger, 1950, Mahavamsa or the Great Chronicle of Ceylon, Ceylon Government Information
Department. Archive.org. Web. 8 Nov. 2011.
<http://www.archive.org/stream/mahavamsaorgreat00mahciala/mahavamsaorgreat00mahciala_
djvu.txt >.
De Silva, Ranga. Jetavanaramaya. 2010. Photograph. Anuradhapura. Pix.stcscouts.com. 14 June 2010.
Web. 04 Nov. 2011. <http://pix.stcscouts.com/rangadesilvablog/?p=1440>
Jetawanarama Dagoba Ruined. 2009. Photograph. Ancient Ruins, Anuradhapura, Ceylon. Lankapura.
2009. Web. 04 Nov. 2011. <http://lankapura.com/2009/05/abhayagiri-dagoba-ruined-at-
anuradhapura-ceylon/>.
Bryenh. Sri Lanka | Anuradhapura. 2010. Photograph. Flickr. 22 June 2011. Web. 08 Nov. 2011.
<http://www.flickr.com/photos/bryenh/5911597784/.<http://www.flickr.com/photos/bryenh/
5911597784/>.
Loroj. Anuradhapura Jetavanaramaya. 2010. Photograph. Flickr. 24 May 2010. Web. 08 Nov. 2011.
<http://www.flickr.com/photos/26751081@N06/4636335478/>.
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