Page 34 - Industrial Plant 2020

w/e bridge sections. On the Eastern bridge pylon
another structure was positioned at the top end of the
bridge with No. 2 additional strand jacks with
counterweights with the task of providing a
counterbalancing action during the lowering (see
details of strand jacking positioning and activity,
pictures 4 , 5, 6)

Chronicle of the ‘Morandi’ bridge
demolition

As described in the previous pages the first operation
was the removal of the Berger beam no. 8, comprised
between V shape piles No. 7 and No. 8. (please refer
to picture 7) . The 916 ton bridge deck was lowered
by strand jacking system at a speed of 5 m/per hour.
Following the same procedure (positioning of the
Picture 3 with the task of balance the whole structure. No. 2 counterweights and strand jacks; removal of decks
support beams were transversally positioned constraints such as fixed and mobile joints; lifting
underneath the Western and Eastern bridge pylons in action of the beam by a few centimeters; cutting
order to anchor all the lifting/lowering structure to the operation with diamond wires), Berger beam no. 7
(weighing 850 ton, pictures 8a and 8b, 8c), beam no.
6 (916 ton) and beam no. 5 of (916 ton) were lowered
by strand jacking system in two months. The section
were taken away by Fagioli SPMTs.
In the meantime on March the 18th, No.5 cranes
arrived in Genoa, to be used for the dismantling
operations of the Western piles. The two main cranes
had a capacity of 600 ton. The deck beam number 3,
Picture 4 was sectioned into smaller beams and lifted by the 600
ton capacity crane. The presence of asbestos in some
of the sections (the bridge was built in 1963), slowed
the operations of demolition. By the end of March,
deck beam number 4 (picture 9) was lowered and
touched ground. In order to be able to disassemble
this section weighing 920 ton in complete safety and in
compliance with the regulations in the presence of
asbestos, the cutting operation was subjected to
continuous irrigation of water which was then collected
and analyzed.

Removal of “V”-shape piles

V Shape pile no. 5 was the first pile to be demolished
on the West side of the bridge. The operations started
with the removal of the lateral parts, the sidewalks.
Picture 5 Subsequently it was necessary to make some holes
for the passage of the slings. The deck was sectioned
in three parts in the longitudinal direction: the first
section weighing 300 ton was lowered on the 16th of
April; the second (310 ton) on the 19th of April and,
eventually the third one on the 26th of April by Fagioli
crawler cranes (pictures 10-11-12).
After the three portions of deck beam, the pillars were
Picture 6 also sectioned to two thirds (picture 13) of their height

IndustrIal Plants - May 2020
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