e-mosty December 2018 e-mosty December 2018 | Page 72

Suspender Support System
was proposed to reduce the structural weight. The
diameter of exposed bridge piers was 4m.
When considering the fatigue damage and corrosion
which often occurs in the fracture of the short
suspenders, double suspenders with various sections
having different vibrating frequency were adopted.
The bearing capacity of the lateral single row
suspenders was calculated based on the dead load of
adjacent spans to prevent the potential collapse of
cantilever beam once a single suspender is broken.
This also allows the replacement of a suspender
without disrupting the traffic or during the normal
service cycle of 30 years.
The piles had a variable cross section with three
diameters: 5.6m / 3.5m / 3m, as shown in Figure 19. The
upper section of pile with 5.6m diameter part was built
in an open caisson, and lower 3.5m diameter part was
cast-in-place pile bored into the underlying soil. The 3m
diameter sections were bored piles embedded in
bedrock.
The deck system comprises tied girders which are two
single box continuous beams with 190m length, 11.75m
width and 2.5m height. Three circular CFST sections were
used in the main arch ring, and the suspension cables are
a series of parallel wire cables.
The deck system was constructed by incremental
launching method using temporary supports in the river,
and then the main arch ring steel tube was constructed
by a vertical rotation method from a horizontal position.
Then the concrete of the main arch ring was pumped
along the steel tube and the deck system was connected
to the main arch ring by suspension cables.
The bridge has 96 double suspenders, including 64
double suspenders on both sides and 32 double
suspenders in the central section. Double suspenders
on both sides consist of 55 parallel wires and 61
parallel wires with the diameter of 7mm, respectively
and the central double suspenders consist of 61
parallel wires and 73 parallel wires with the diameter
of 7mm, respectively.
CFST TIED ARCH BRIDGE CONSTRUCTED
BY
INCREMENTAL
LAUNCHING
WULITING BRIDGE IN SHAOGUAN CITY
METHOD:
For this bridge a new main arch ring with three tubes
was proposed (as shown in Figure 20) to solve in-plane
buckling of this bridge. The arch is composed of two
0.85m diameter tubes at the bottom, one 1.8m diameter
tube at the top and stiffened plate connections between
three tubes.
The Wuliting Bridge was constructed on the ring road
in Shaoguan City, Guangdong Province, China, in
2003. The total length of the bridge is 505m, width
30m, the main CFST tied arch bridge is combined with
prestressed concrete continuous girder with spans
35m+120m+35m. It was built using an incremental
launching method.
The main foundations of this bridge comprise a single
non-uniform section pile without a pile cap. This
variable cross section pier-pile combined structure
Figure 18: Wuliting Bridge
4/2018
Figure 20: Cross-section of main arch ring structure