Tunnelling /

We design tunnels and shafts for water, wastewater, roads, highways, rail and transit systems...

We design tunnels and shafts for water, wastewater, roads, highways, rail and transit systems, prepare contract documents, procure the services of a suitable tunnelling contractor and provide construction inspection and management services during construction and warranty periods.  Our services include:

  • Design of tunnels (200mm to 30 m diameter) and submission at various phases to suit client schedule, from concept to the detailed design, Issue-for-Bid and/or Issue-for-Construction
  • Performing data collection (subsurface ground condition, subsurface utility, property, subsurface environment, social and cultural environment) and interpretation (E.g.: Geotechnical Baseline Reports)
  • Identify and assess alternative tunnel & shaft design options and recommend suitable methods to suit the local surface and subsurface conditions
  • Determination of the most appropriate tunnelling methodology and approach based on the ground condition.  The tunnelling methods include the use of Horizontal Directional Drilling (HDD), pipe jacking, auger boring, Earth Pressure Balance (EPB) Micro-Tunnel Boring Machine (MTBM),Earth Pressure Balance (EPB) Tunnel Boring Machine (TBM), Slurry TBM, Rock TBM, Sequential Excavation Method (SEM), and cut-and-cover method
  • Preliminary and detailed engineering services for underground excavations and structures including:
    • Ground improvement techniques include Dry Soil Mixing, Dynamic Compaction, Earthquake Drains, Rapid Impact Compaction, Rigid Inclusions, Wick Drains, Soil Mix Walls, Wet Soil Mixing, Vibro Compaction, Jet Grouting, Permeation Grouting and Ground Freezing.
    • Initial support for tunnels
    • Precast Concrete Tunnel (segmental) Lining compatible with the TBM and ground condition, reinforced with conventional rebar or steel fibre
    • Cast-in-place tunnel lining
    • Final structures for shafts and cut-and-cover
    • Support of excavation for shafts and open-cut excavations in rock or soft ground.  This includes Anchors, Anchor Block Slope Stabilization, Gabions, Sculpted Shotcrete, Secant Piles, Sheet Piles, Slurry Walls, Soil Nailing, Soldier Piles & Lagging
    • Cross Passages and Emergency Exit Buildings (transit tunnel only)
  • Preparation of drawings, technical specifications, cost estimates and complete contract documents.
  • Coordination and exchanging information with client, third parties and regulatory agencies
  • Environmental permitting
  • Resident engineering and contract management services
  • Construction quality inspection and certification
  • Structural Monitoring
  • Settlement Monitoring
  • Risk management
  • Project management