Materials
Ancient stupas are made of
bricks. Between these bricks,
there is a very thin plaster layer.
This has made brickwork stronger
compared to modern-day
brickwork which has a thick mortar
layer between the brick layers.
Different sizes of bricks had
been used in the construction of
stupas.
Location
Dimensions
(LxWxT- mm)
Mass (kg)
Basal rings 320x280x85 12.30
Dome 450x230x80 13.10
Square chamber 250x160x70 5.15
Spire 210x150x55 2.48
Size of bricks used in stupa construction
When compared with modern-day bricks (215 mm x 102.5 mm x 65 mm), these ancient bricks are
larger in size and contain a higher compressive strength.
Property Ancient bricks Modern bricks
Compressive strength 8500kPa 5300kPa
Tensile strength 850kPa 550kPa
Poisson’s ratio 0.25 0.21
Comparison of ancient
and modern bricks
Young’s modulus 4.5GPa 1.92GPa
According to studies, ancient bricks
have more sand content than modern-day
bricks. For example, bricks in Jethawana
stupa have a sand content between 50%
- 60%.
This might be a reason for the strength
in the bricks. The brickwork was waterproofed
by the dense plaster layer which
covered the bricks.
Sometimes there were several layers of
plaster which were around 9 - 10 inches
of the overall thickness. (Ranaweera and
Abeyruwan, 2004)
Comparison of ancient and British era brickwork
in Jetavana
Page 14
University of Peradeniya GAUGE Magazine