Immersed Tunnels

Introduction Development of the Immersed Tunnel Steel shell tunnels Concrete tunnels Composite sandwich tunnels Tunnels in Japan Growth in immersed tunnels worldwide Current Forms of Immersed Tunnel Monolithic concrete element construction Segmental concrete element construction Prestressed concrete Single steel shell Double steel shell Composite concrete steel sandwich Developing an Immersed Tunnel Scheme Selection of bridge or tunnel Tunnel cross section Alignment Junction with cut and cover tunnels Number of tunnel elements Geotechnical Structural options Element construction Environmental considerations Disruption to navigation Cost Operation and maintenance costs Construction program Environmental Impact Short-term versus long-term impacts Tunnel approaches Marine works Fisheries Algae Water quality Visual aspects Portals Noise Air quality Marine Environment Hydrography Hydraulic effects Modeling Mechanical and Electrical Installations Road tunnel safety Incident detection and management Emergency escape Railway tunnel safety Ventilation Lighting Control systems Power supply Drainage Tunnel Approaches and Service Buildings Forms of approaches Cut and cover tunnels Approach ramps Interface with immersed tunnel Construction sequence Connection to bored tunnels Use of tunnel approaches as the casting basin Service building facilities Layout of tunnel portal areas Design Principles Structure sizing Stability and buoyancy Design loadings Temporary load conditions Design codes Load combinations Structural analysis Structural design Settlement modeling Seismic design Joints Immersion joints Segment joints Terminal joints Closure joints Crown seal joint Seismic joints Durability Watertightness Concrete mix design Early age crack control Membranes Corrosion prevention strategies Cathodic protection Durability of watertight seals Internal coatings Foundations Foundation layer Sand foundation layers Gravel foundation layers Grouted foundations Piled foundations Ground improvement Earthworks Dredging Backfill Cut-and-cover tunnel earthworks Casting basin Artificial islands Construction and Placing of Tunnel Elements Concrete tunnels Steel tunnels Utility tunnels Temporary works equipment Float up Transportation Immersion Ballast exchange Lessons learned Finishing Works Tunnel entry procedures Joints Ballast concrete Fire protection Cladding, kerbs, and crash barriers Drainage Rail tracks and road surfacing M&E installation Operation and Maintenance Operation Maintenance Rail tunnels Contract Forms Form of contract Contract documents Ground conditions Dispute resolution Insurance Payment Privately financed construction The Future Going longer Going deeper Materials Submerged floating tunnels Location Glossary References Index