INGENIEUR
Side view of the stone arch
bridge with the four smaller
arches that serve to reduce
the load and to allow more
sectional flow of water during a
flood season.
center and extends up to 9.6m
on both ends of the bridge.
The arch resembles a circular
segment with a radius of 27m
where the rise-to-span ratio is
about 0.197 and arch length to
span ratio is 1.1. These ratios
are comparatively small when
compared with the semi-circular
arch ratio of 0.5 and 1.57
respectively. Such a reduction
in ratio translates into savings in
materials and hence a reduction
in the load that the bridge exerts
on the supporting abutments on
both sides of the river. Li Chun’s
ability to locate the rock base
of the river bank to support
the 2,800 tons stone bridge is
both a marvel and a mystery.
According to the records, the
abutments have only settled
about 5cm during the 1400
years since it was built.
There are four side arches
that serve to reduce the weight
of the structure. When the
water level reaches the top of
the bridge deck during a flood,
the four arches allow a greater
volume of discharge as well as
reducing the impact of the water
on the bridge.
The central arch was
constructed with 28 thin,
curved arch segments made
of limestone slabs which are
joined with iron dovetails. Five
iron rods go through the 28
arch segments to hold them
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together and form the main
spandrel arch. Dozens of
dovetails join the segments in
a tight and integrated manner.
The combined arches provide
an integrated structure in
sustaining the loads through an
even and effective distribution
of forc e s . This ef f icient
interlocking of forces prevents
the collapse of the structure
when one segment of the arch
is broken. It thus makes it
easy to repair the arch since
the individual segment can be
easily replaced.
The bridge floor is smooth
and flat with passages for
pedestrians on both sides,
while carriages and carts can
move along the middle. The
apex of the bridge is fairly high
to allow the boats to pass
through with ease. The bridge
is ingeniously designed with a
well-proportioned layout, solid
structure and a magnificent
appearance.
Guard slabs on either side
of the bridge are engraved with
delicate patterns of dragons,
which are a symbol of water
god in the Chinese culture. The
design of this arch bridge has
influenced the construction of
bridges in other parts of China.
The Zhaozhou Bridge is
an hour’s drive away from
Shijiazhuang, Hebei provincial
capital.
The plaque with inscription
of American Society of Civil
Engineering as the “12th
International Civil Engineering
Historical Monument” endorsed
on September 4, 1991.