Visp Valley, Switzerland

The town of Visp in southern Switzerland is located at a strategic pinch-point for traffic passing through the narrow Rhone valley. The Visp Tunnel is a section of the new Visp south bypass. It is a complex underground structure, consisting of the north and south directional road tubes between the Schwarzer Graben and Chatzuhüs (Staldbach Bridge junction), and the underground interchange with the motorway to the Visp Valley. The main objective of the new tunnel is to enable a sustainable and future development, which links the whole Valais and brings real value to the population, industry and tourism.

Project Requirements


  • C 30/37 CL 0.20,
  • maximum particle diameter 8 mm


  • C 35/45 XC4/XD3/XF4/CL0.1,
  • maximum particle diameter 32 mm


Sika Solutions

Sika was able to provide a complete solution for the many different concrete mix designs and applications required on this project, including all of the sprayed and site-placed concretes, as well as the structural waterproofing systems. This amounted to some:

150,000 m³ of sprayed concrete
185,000 m³ of site-placed concrete
150,000 m² of Sikaplan sheet waterproofing system, which were used in this project

In close support of the Project Engineers and the Contractors on site, Sika was also able to assist and provide the right products for many other different applications during this project.


Products Used

  • Sika® ViscoCrete® – superplasticiser and ultra-plasticiser
  • Sika Sigunit® – shotcrete accelerator
  • Sika® Separol® – formwork release agent
  • Sika® Antisol® – curing agent
  • Sika Boom® – expanding foam sealant
  • Sika® Rock – anchor mortar
  • Sikament® – superplasticiser
  • Sika® Retarder – retarding agent
  • Sika® Fro – air entraining agent
  • Sika® Frost Protection – mortar additive
  • Sika® Stabilizer – anti-segregation additive
  • SikaControl® – crack reducing admixture
  • SikaRapid® – concrete hardening accelerator
  • SikaFume® – silica fume additive
  • SikaPump® – concrete pumping aid
  • Sikaplan® WP – sheet waterproofing membrane system
  • Sikaplan® WP Protection Sheet – waterproofing membrane protection
  • Sika® Waterbar – movement and construction joint waterstops
  • Sika® Dilatec® – waterproofing and sealing tape

Project Participants

Kanton Wallis built to order of ASTRA (Federal Office for Road

ARGE Tunnel Visp (ATV)
Imboden Ulrich AG, Visp
Prader Losinger SA, Sion
Dénériaz Sion SA, Sion
Evéquoz SA, Conthey
STRABAG AG, Erstfeld

Planner and Engineers
IG Vispa
IUB Engineering AG, Bern
Rothpletz, Lienhard + Cie. AG, Bern
SPI AG, Brig-Glis