e-mosty June 2017: Osman Gazi B. US Suspension. Hålogaland B. e-mosty June 2017: Suspension Bridges | Page 17

Pulling of the strands was done symmetrically (one
strand from the eastern side, then one strand from
the western side of bridge). Adjustment of the strands
length was also done during this time. The extra back
strands leading from tower to anchorage were
anchored at the tower saddle, see the picture 21
below.
After all strands were pulled and adjusted the
compacting of the cables was performed.
This pressed all strand wires closer together and
formed the oval shape of the cable. The void ratio
(space between wires) of the cables was around 20%.
This was done using the hydraulic compacting
machines.
The cables were then fitted with clamps, to which the
hangers are attached.
It was followed by installation of the hangers (vertical
cables), on which the box girder will be attached. The
hangers are also made from steel wires in the form of
locked coil cable with three layers of z-shaped
galvanised locked wires. The hangers are protected by
7mm HDPE sheathing.
On both ends of the hanger there is a cast socket. The
upper socket is attached to the cable clamp and the
lower one is attached to the bridge deck. The hangers
were also fabricated in workshop and then
transported to the site.
In the first four stages of construction (installation of
strands, compacting, installation of cable clamps and
installation of hangers) cables were parallel to each
other.
After the installation of the hangers, the cables were
separated laterally from each other to form the final
shape according to the design. The lateral shifting was
done using the shifting beams and hydraulic jacks. At
this stage, the main span´s catwalk was separated into
two parts.
Then the cable bundle was wrapped with a soft
galvanised wire to maintain its shape. Even though
the strands were tightly compressed, the cable still
contained around 20% air. The cables will be
dehumidified by injection of dry air.
Figure 20: Cable clamps
Figure 21: Anchorage of back strands at the tower saddle
Figure 22: Compacting of the main cable
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