Busan Geoje Fixed link Tunnel

Busan, South Korea
HEIGHT: 9.97M
WIDTH: 26.46m typical 28.46m maximum
TOTAL IMMERSED LENGTH: 3240m
DEPTH AT BOTTOM OF STRUCTURE: 48m
ENVIRONMENTAL CONDITIONS:
Open sea conditions with large waves
Soft soil conditions
Heavy ship traffic from nearby harbours
FABRICATION METHOD:
Tunnel elements constructed in 8 segments in casting basin.
Elements temporarily pre-stressed
t123
t123-busan-geoje
Busan Metropolitan City, Gyeongnam Province
Daewoo Engineering & Construction Co, Ltd.
COWI-DEC JV
180m
3240m
48m
2010-05-01
18
Two traffic tubes with 2 normal traffic lanes and shoulder each. Climbing lanes instead of shoulders in uphill direction tube for two elements. Central service tube with electrical installations, smoke extraction duct, drainage and water pipes.
9.97m
26.46m typical 28.46m maximum
Climbing lanes in cross section for some tunnel elements.
Smoke extraction system with capacity to remove smoke for small or initial stage fires
supplementing longitudinal ventilation under traffic queuing conditions.
Parts of the tunnel at each end are above existing sea bed level, and a section is placed on a
sub sea embankment. Tunnel elements at these sections are designed with protective reef to
resist horizontal accidental ship impact.
Soil improvement by cement deep mixing for the whole length of the tunnel due to soft soil
conditions except where it is placed on an embankment. In the embankment area the ground
treatment has been carried out using sand compaction piles.
The tunnel is designed for large typhoon waves and moderate-size earthquakes.
Immersion is complicated by large water depths and the presence of sea waves.
Tunnel elements constructed in 8 segments in casting basin.
Elements temporarily pre-stressed
Takes place at casting basin
site and at mooring area where
elements are stored up to 1
year.
Open sea conditions with large waves
Soft soil conditions
Heavy ship traffic from nearby harbours
To be decided by Contractor.
Immersion joints: Gina gasket
and Omega seal.
Segment joints: Injectable
water bar and Omega seal.
Watertight concrete, i.e. no membrane applied.
Soil improvement partly by cement deep mixing and partly by sand compaction piles. The
foundation layer designed as a combination of a grouting and a gravel bed foundation.
Backfilling with crushed stone, top
protection by armour stones and precast
concrete armour units for sections
with large wave impact
Concrete grade 35 MPa. Temporarily prestressed.
Design in accordance with AASHTO
LRFD standards.
1.025 for temporary condition and 1.06 without backfill taken into account for permanent conditions. The stability of the tunnel (both vertical and horizontal) is under influence of large waves and has according to special analysis necessitated additional