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