As the world's longest rail tunnel, the 57 km-long structure is both a novelty and a tour-de-force in tunnel engineering which forms the centerpiece of the new transalpine rail route (NEAT). It embodies the Swiss values of innovation, precision and reliability. These values – upheld at all levels with pride, satisfaction and in a true spirit of partnership by Sika's project team on a daily basis throughout the 14-year construction period and, even before that, during the preliminary phase from 1996 – have helped to cement the success of this once-in-a-lifetime project. The Gotthard base tunnel is an impressive demonstration of how Sika builds with and for people.

A few facts and figures about the tunnel:

  • Construction period (excluding exploratory work): 17 years
  • Length: 57 kilometres ( a tunnel system of 152 kilometres in the rock)
  • Two (2) single-track tunnel tubes,connected every 325 metres by cross cuts
  • Tunnel summit: 500 m above sea level
  • Maximum rock cover: 2,300 metres
  • 28.2 million tonnes of material excavated
  • Main tunnels drilled with tunnel boring machines (80%) and blasted (20%)
  • 43,800 hours working non-stop to lay the ballastless track
  • Effective total cost: about CHF 23 billion
  • Project participants: 2,600 people
  • Gotthard Base Tunnel commissioning: 11 December 2016

Learn more at:

The Sika products that were used on the project

Shotcrete, blasting
Shotcrete, blasting and TBM drilling:
  • Sika® ViscoCrete®SC Plasticizer
  • SikaTard® Retarder
  • Sigunit® Accelerator
  • SikaFume®
  • Concrete additive
  • SikaPump® Start-1 Pumping agent
  • FlexoDrain W Channels
Application equipment
  • Sika® PM-500 PC sprayed concrete system
  • Sika® PM-702 Concrete pump
  • Aliva®-503 Concrete spraying machine
  • Aliva® L-1/L-2 TBM sprayed concrete system
  • Aliva® AL-278 Concrete pump
  • Aliva® AL-403 Dosing unit
Gotthard Tunnel Waterproofing
Waterproofing of tunnel structures:
  • Sikaplan® Sheet waterproofing membranes
  • Sarnafil® Sheet waterproofing membranes
  • Sika® Waterstops
  • Sikaplan® W Felt Protective geotextile
  • Sikaplan® WT Tape jointing system
  • Sika® Trapezoidal Profiles-Formwork inserts
  • Sikadur-Combiflex® System Joint waterproofing
  • SikaSwell® Sealing profiles
Site-placed concrete
Site-placed concrete:
  • Sika® ViscoCrete® Plasticizer
  • SikaTard® Retarder
  • SikaPump® Pumping agent
  • SikaPump® Start-1 Pumping agent
  • SikaFume® Concrete additive
  • Sika® Separol® W Formwork release agent
  • Sika® Mixer Protector, Surface protection
Immediate stabilisation and anchor bonding at critical points
Immediate stabilisation and anchor bonding at critical points:
  • Sika® Rock Shot-3 Dry sprayed mortar
  • Sika AnchorFix® Anchor adhesive
  • Sika® Intraplast® Injection additive
  • Sika® Fix T-10 RX Injection resin
  • SikaCem®-501 Rapid hardening cement
  • Aliva®-252 Concrete spraying machine
Ancillary products available
Ancillary products available onsite everyday:
  • Sika MonoTop® Patching mortar
  • Sikadur® Repair mortar
  • Sika® FastFix Rapid hardening mortar
  • Sika®-4a Rapid hardening binder
  • SikaGrout® Grouting mortar
  • Sikafloor®-2530 W Floor coating
  • Sikaflex®-11 FC Sealant
  • Sika Boom® Foam Filler
Technical advice and service locally:
  • Site supervisors
  • Technical advisors
  • Concrete & mortar service team
  • Equipment service engineers
  • Product managers
  • Customer service - Orders and deliveries

Sika’s expertise on the jobsite

The new Gotthard tunnel project required Sika to draw on the full breadth of its construction expertise. Waterproofing systems, construction chemicals know-how and machinery solutions were only part of the package. High-grade shotcrete was used to support the tunnel excavation. This served as the base for the Sikaplan® and Sarnafil® waterproof membranes. The concrete lining was then placed using Sika admixtures so as to achieve the high degree of precision required for the tunnel surface geometry. The flawless concrete finish is a visible testament to the outstanding concreting workmanship.

Learn more at: