e-mosty September 2018 Vessels and Equipment Used for Bridge Construction | Page 82

DECK ERECTION OVER WATER (Main and Side Spans)
Advantages of Producing the Steel Towers and Deck locally
in Turkey include:
The steel deck sections for the suspended spans over
water (i.e. for the main and side spans) were erected by
the Turkish fabricator Çimtaş under the EPC Contractor’s
supervision (IHI-ITOCHU JV).
Sea transportation of the manufactured elements for the
steel towers and deck in distant foreign countries could
have increased the risk of fatigue due to the following.
 The need to stack superstructure sections on
vessels
 The potential for wave actions induce fatigue
stresses in superstructure sections
Following activities were completed for the deck:  Deck Panel Fabrication; Steel was cut and welded to form
stiffened panels at the ÇIMTAS Gemlik factory. Potential
fatigue
transportation
 Potentially shortened fatigue life of in-place
structure
The deck panels were fabricated at the “Çimtaş factory”
60 km southwest of bridge sitethen delivered to the
“Çimtaş Shipyard”
km east of bridge site and
assembled to form deck segments 36m wide and 25m
long.
Deck Segment Assembly; All semi-finished product panels
coming from the ÇIMTAS Gemlik Works were delivered
to ÇI TAS Gölcük Works on trucks Panels were
assembled by welding and assembling into a semi-
segment and then these semi-segments were
transported and manoueuvred at the assembly yard by
SPMT. Semi segment to full segment assembly was
performed in open areas, and shelters were used to
cover welding areas.In total 87 decks segments were
made.
Trial Assembly; Each completed segment was trial
assembled with its adjacent segments.
cracking
during
sea
Minimising Disruption to İzmit Bay navigational canal
Traffic
The works were planned and carried out very carefully to
avoid disrupting canal traffic. The shipping channel was
changed several times by Harbour Master to arrange
optimum working conditions for bridge erection and
passing ships.
Transportation of Deck Segments:
Deck Erection; Deck segments were transported on a
barge in approximately 3 hours of sailing time to the
construction site for erection by floating crane or by
lifting devices.
Deck segments with a size off 25 or 50m long x36m wide
were transported by self propelled barges from Gölcük
Shipyard to the their final locations.
approx. 30 km
Figure 44: Marine Transportation of Deck Segments With three Barges “Rising Sun”, “Ay Yıldız” and “GMK-1”
3/2018