BHUSAN GEOJE FIXED LINK

1. GUIDED BY :
V.K.RAHMAN

2. CONTENTS
• Introduction
• Phase of project
• Description
• Design condition
• Construction
• Project cost
• Advantages
• Conclusion
• Reference

3. INTRODUCTION :-
The Busan – Geoje Fixed Link project is highly challenging
infrastructure scheme to cut down journey time between korea’s south
coast city of Busan and the island of Geoje.
The link consist mainly three parts which are :
• A three-pylon cable-stayed bridge
• Approach bridges with cable-stayed and road and rock tunnels on
islands
• 8.2 km long link, which includes immersed Tunnel of 48m depth

4. Phase of Project
 Total length : 8.2km
Lot 1 bridge : 1.65 km
Between Geoje and Jeo islands, a 1.65 km bridge , includes a three-pylon
cable-stay bridge. This bridge has two mainspans of 230 meters with side
spans of 106 meters.

5. Lot 2 bridge : 1.87 km
between Jungjuk and Jeo islands includes a cable-stayedbridge with a 475 m main
span and 220 m side spans.

6. Lot 3: Immersed tube tunnel : 3.2km
The total length of the immersed tunnel is 4 km with two 170 metre long cut
and cover sections at both ends.

7. DESCRIPTION:-
Sunken Tube Tunnel :-
• Tunnel comprises 18 elements that are 180m long.
• Each element was casted in 8 segments in the precasting yard.
• Cost for immersed tunnel is US$1.8 billion [Jin Wook Heo
(Daewoo Engineering and Construction, Ltd.)]

8. DESIGN
CONDITIONS :-
Production
of tunnel
elements
The tunnel elements are 180 m long, 10 m high, 26 m
wide and weigh about 48,000 tons.
The tunnel elements are closed off with steel bulkhead
panels on both ends.
After finishing each batch, the precast yard is flooded and
The tunnel elements are floated up, flooded out and
transported to a nearby location.

9.  Bridge :-
• Caisson foundations have been used for the piers and pylons as
they eliminate the need for water excluding temporary works.
• The caissons are 33m high precast concrete cellular structures.
• The caisson foundations were fabricated at a casting yard on the
mainland.

11. Erection of pylon

12. Contd….
• The lower sections of the pylons are filled with rock ballast up to a height of
16m to protect against ship impact.
• The bridge deck consists of a steel framework which supports a concrete slab.
• Both sides of the pylon were placed consecutively to balance the loads.

13.  Hydraulic pressure :-
• The deepest foundation point of the tunnel is 47m below mean sea
level.
• The water pressure imposes a significant load on the tunnel
elements.
• An increase in the mean sea level of 0.4m has been included due to
the global warming.
Waves and current :-
• Most waves at the project area are generated by winds including tropical
storms and typhoons.
• Waves generated by distant storms can also reach the tunnel alignment from
southerly directions.
• Tidal range varies between 0.8m and 1.6m.

14. SHIP IMPACT
• The southern coastline of Korea has a large volume of sea going
traffic including containership, gas & oil tankers.
• Militarily it is an important area.
• Overall impact of Bhusan-Geoje fixed link project considered
loadings from impact and sinking of 50,000 ton vessel sailing to a
neighboring port.

15. CONSTRUCTION :-
 Soil improvement / foundation :-
• Marine clay is forming the sea bed except in the near shore areas
where bed rock outcrops.
• The thickness of the marine clay along most of the tunnel
alignment exceeds 20m.
• The major part of marine clay was “very soft to soft” and of “very
high plasticity” to “extremely high plasticity”.
• To make the foundation more robust, soil improvement with
cement deep mixing (CDM) and sand compaction piles (SCP)
was chosen.

16. Typical CDM(cement deep mixing) foundation layout at tunnel
elements.

17. Cement deep mixing (CDM)
• Where the tunnel is placed in a trench the clay was strengthened
with walls formed by contiguous columns of mixed cement and clay.
• The mixing shafts were first drilled with the rotating blades into the
soil to the desired depth.
• The cement slurry is injected in the withdrawal stage, where the
vertical speed of the machine and the flow rate of the cement slurry
were kept constant.

19. Mixing blades of the deep mixing machine and offshore CDM
production barge

22. Sand compaction piles (SCP)
• Sand compaction piles are used where the tunnel was constructed
on an embankment.
• Sand compaction piles have been chosen in order to allow quick
consolidation and strength gain of the clay.
• The SCP have a diameter of 2 m and reach depths of up to 65 m
below sea level.

23. Construction of bridge
 The geology of the site generally comprises marine deposits (sandy and clayey
layers) overlying residual soil (formed by decomposing and weathering of the
bedrock in places) and bedrock.
 The foundations for the Lot 1 bridge piers were founded on weak or hard rock,
located in up to approximately 30m of water.

24. Contd….
 The foundations of Lot 2 is generally similar to those of the bridge
in Lot 1, except for the presence of an ancient valley in the bedrock
in-filled with approximately 18 m of marine clay.
 Being located in the open sea, the bridges were exposed to
extreme wind and wave conditions from typhoons so based on
this experience.
 The bridges were designed for wave heights of up to 13 m with
critical wind speeds up to 80 m/s.

25. Project cost
Total cost -1.8 billion
Govt. subsidy- 0.45 billion
lead contractor- Daewoo Engg. & Construction company
• Project has been designed for service life of 100 years.

26. ADVANTAGES:
 Economic use of shape (cross section)
Vertical clearance
Soil condition:- advantages for a soft soil condition when
a bridge support is difficult
Capable of dealing with seismic effect

27. CONCLUSION
The design and construction have been modified in order to
overcome a number of difficult conditions.
These kind of projects like Busan-Geoje fixed link, Millau viaduct,
palm Island are wonders of new era.
So as an engineer we can say that with the help of our knowledge
and technology we can create more wonders like Busan-Geoje Fixed
Link.

28. REFERENCES
• [1] http://www.roadtraffic-technology.com/projects/busan
• [2] http://www.strukton.com/projects/busan-geoje-fixed-link/
• [3] http://www.industrytap.com/drive-through-the-deepest-immersed-sea-highway/7892
• [4] International Journal of Innovative and Emerging Research in Engineering Volume 2, Issue 3,2015 .