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 This is the first cable-stayed highway and railroad
multipurpose bridge with low towers and cable-stayed of main bridge,
designated as the key project in the National 9th Five-Year Plan. The
steel griders with main bridge ramains 5 spanΧ14arches continual girders
with main span of 312m and across Yantze River
of 2,193m long. This bridge adopted new material of 14MnNbq made by
China and technique of integral panel joint, and it is the bridge of
an integral for new structure、new
material and new technique.
Steel girders fabricated over 90% of
the engineering was contracted by CRTBI in 1998. During manufacturing
we aimed at the fabricated difficulties:
(1) The steel
girders have adopted structure of integral panel joints, breaking
through components with railroad steel truss is incapable of
conducting old method with transverse butt. Butter weld joint and the
three-section -30C Charpy V impact function with angle weld joint on
slope orifice pulled is no less than 48J.
(2) The four main weld joints has adopted the welding
of deep slope orifice due to large chord surface with integral panel
joint and thick plate, and a part of weld joint need to melt down, so
the control and rectification for welding distortion remain quite
difficulties;
(3) The precision with hole location for high
strength bolts connection with hole cluster remained difficulties to
guarantee due to the complicated relation between integral panel
joint and large components;
(4) The ventral pole of main trusses connection with
chord shall adopt connection of inserted method to between joint
plates and guarantee inserted clearance to meet the installation
requirement. So increasing difficulty for fabrication due to quite
high specification between the distance of joint plate and the geometrical
precision of ventral pole.
(5) Due to the structure complex with slant-pull span
anchord-box, more weld joint with melt down and complex interspace
connection relations so the fabricated precision can't guarantee. In
order to embody indeed the design thoughts, carrying out fine quality
engineering goals of striding century, CRTBI has taken aim at the
most advanced technique with bridge fabricated in current world,
taking "good quality、superior
efficiency" as a tenet, actively organising scientific and
technical personnel and workers for bridge according to key problem
with high strength、integral、large span、new
structure. Researched and adopted the following technique:
fabricated, the strength of increasing scentific and technical :
(1) The fine cutting techniques in the outside edges
of railway bridges
(2) Welding new techniques with 14MnNbq new steel
materials manufactured by China.
(3) Manufacture techniques of integral panel joint
with weld in thick plates.
(4) Predistortion processes for weld components on
deep slope orifice of thick plates;
(5) Locating measurement techniques on the hole
cluster of bridge components;
(6) Chord pole with integral panel joint has adopted
the boring process of boring die with the whole cover types of
platform lining;
(7) The group welds with shearing force nail and
control distortion techniques;
(8) Large-scale complex components - integral panel
joint chord with the turning over techniques in air;
(9) Box-type components with anticorrosion greasy
techniques;
(10) Large-scale complex anchord-box components
fabricated techniques;
(11) Overlength trial-assembling techniques for the
sixth parts with main span of slant pulled bridge in factory
(12) Technique of temperature controlled with the hot
wind screen. New process and new technique guaranteed bridge erecting
favorably in site and won high praises with good quality and
excellent manufacture precision by employer and erecting unit. CRTBI
not only had created history record with 3,696t steel girders of
month output but also finished assignment contracted at 5 days ahead
of 10, April 2000 with excellent quality and quantity. The bridge had
been carried out to close down with zero error in 2, may 2000 and
created new rocord in the history of bridge construction in China
and was acclaimed by bridge construction experts as another milestone
in the history of bridges construction. At present, WuHu Yantze
River Bridge
has awarded Luban prize from construction engineering in China.
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