Jintu International
Engineering Limited

Section & Length

9.4m (W) × 4.38m (H) × 43.5m (L)

Technical Highlights

• ✓Double-Row Steel Sheet Pile Launch Structure : Adopted double-row steel sheet pile structure at the launch shaft to improve safety during RTBM launching in absence of vertical reinforcement capability.
• ✓Composite Thick Slurry Compensation Grouting (Hong Kong First) : Deployed composite thick slurry compensation grouting technology for the first time in Hong Kong, enabling ground deformation control at the millimeter level.
• ✓Segmented Modular RTBM Reception in Confined Shaft : Implemented segmented modular RTBM reception within a small, irregularly shaped receiving shaft where conventional methods were infeasible.

Section & Length

13.04m (W) × 9.61m (H) × 133.5m (L)

Technical Highlights

• ✓Cross-section 125m² at 26m depth — largest section, depth and water pressure for rectangular pipe-jacking in China
• ✓133.5m drive through soft silty soil
• ✓7.58m clearance from existing shield tunnels on both sides
• ✓No reception shaft — in-tunnel shell abandonment
• ✓Encountered reinforced ground, boulders and construction debris causing cutter-head and screw-conveyor blockages

Section & Length

10.2m × 6.6m + 7m × 5m

Technical Highlights

• ✓Stacked-line pipe-jacking for turnback and transfer tunnel; single drive 140.4m
• ✓Through gravelly clay and fully weathered granite
• ✓Large RTBM overran Line 2 tunnel with only 3.2m vertical clearance
• ✓No normal reception conditions — large machine received in-tunnel then laterally shifted 118m for extraction

Section & Length

10.4m (W) × 7.5m (H) × 90m (L)

Technical Highlights

• ✓Dual 4-lane carriageway; twin tubes at 2.5m spacing, total drive 180m
• ✓Underpassed active tram line and busy Meihua East Road
• ✓Underpassed DN1000 sewer with only 1m vertical clearance
• ✓Multi-arc near-rectangular section with high prefabrication precision requirements
• ✓Granite boulders and bedrock protrusions — pioneered China's first patented bedrock pre-treatment technology

Section & Length

9.8m (W) × 5.9m (H)

Technical Highlights

• ✓South tube 154.9m / North tube 215.9m — no intermediate jacking stations used
• ✓Twice underpassed the UNESCO World Heritage Grand Canal with no pre-treatment
• ✓4.39m ultra-shallow cover under 15m water pressure through fine silty sand
• ✓First use of steel-strand tensioning to enhance rigidity and waterproofing in soft waterlogged ground
• ✓20+ authorised patents; results rated 'internationally leading'; multiple national science & technology awards

Section & Length

9.1m × 5.5m + 7m × 5m

Technical Highlights

• ✓Twin-tube parallel drive at 1m spacing
• ✓Single drive 128.4m with no intermediate jacking station
• ✓First twin-tube rectangular pipe-jacking to underpass an expressway in China and Beijing
• ✓Identified and mitigated slope-toe instability risk; settlement control achieved

Section & Length

10.2m (W) × 6.6m (H)

Technical Highlights

• ✓Large 10.2×6.6m section suitable for dual 4-lane carriageway
• ✓Two drives of 138.3m and 143.9m — over 100m each without intermediate jacking stations
• ✓Successfully navigated spheroidal weathered granite boulders and multiple underground utilities
• ✓Three machines operating simultaneously
• ✓First application in China of high-efficiency permanent-magnet drive technology in a rectangular TBM