Gotthard AlpTransit Project

The Ceneri Base Tunnel builds on ideas dating back 1947, when the concept of building a tunnel to enable easy and efficient transport through this area of the Alps was first introduced. Holcim is helping to make this vision a reality.

Gotthard AlpTransit Project consists of two separate rail tunnels passing under the Gotthard and Ceneri mountains to connect Zurich and Milan. With minimal gradients and wide-radius curves, this high speed rail link will reach up to 250 km per hour and reduce the current journey time between the two cities by approximately 60 minutes. Excavation of the Gotthard Base Tunnel began in 2000 and work on the Ceneri Base Tunnel followed in 2007. Project completion is expected in 2019 at an estimated total cost of CHF 2.4 billion.

At 57 km, the Gotthard Base Tunnel is the world’s longest tunnel. This route will carry both passengers and cargo and is intended to significantly reduce the amount of road traffic through the region as a result.

Construction materials and solutions
Almost 100% of the cement and most of the primary aggregates and concrete needed for the tunnel lining and bed are being supplied by Holcim. Holcim was chosen as a partner on this project due to its expertise in logistics, engineering, and materials and its capacity to deliver an integrated solution tailored to customer needs.

Upon project completion, a total of 7.9 million tons of material will have been excavated, transported via conveyor belt from the tunnel at Sigirino, and separated into landfill material or recycled as aggregate for concrete. Around 0.4 million tons of aggregates for this project will be produced in this way, with another 1.6 million tons of primary aggregates delivered via train by Holcim from its Hüntwangen quarry. The cement itself, circa 390,000 tons, is supplied from Holcim’s plants at Siggenthal and Eclépens. A specially designed ready-mix concrete (RMX) plant was installed by Holcim at Sigirino in order to produce approximately 1 million m3 of RMX onsite.

Overcoming project challenges
Difficult geological conditions at the project needed specially adapted concrete mixes. All the recipes had to be resistant to alkali aggregate reaction (ARR) and have the ability to function without difficulty at high temperatures. Holcim therefore developed a cement type tailored to offer early strength, high impermeability, and chemical, fire resistance.

The tunnel itself is expected to have a lifecycle of a hundred years, and this also had to be considered when choosing materials. Perhaps most challenging however was the designing, building, and commissioning of an RMX plant 2.3 km into the mountain in an extremely confined space and within a deadline of ten months.

Improving environmental performance
Сonstructing the Gotthard AlpTransit Project Switzerland is implementing one of Europe’s largest environmental protection projects. By diverting heavy goods transport away from the roads, damage to the delicate alpine environment will be substantially reduced.
 Moreover, the onsite recycling of excavated material for use as aggregates significantly reduces resource use and the need for transportation.