Case Study Elasticity for the Slab Track in the Gotthard Base Tunnel, (CH) The project of the century: With 57 kilometres the world's longest railway tunnel Highest requirements: Outstanding material properties over the entire service life Optimised solution, comprehensive project support and just-in-time logistics Elastic Sylodyn® Insertion Pads for Sleeper Boots in the World's longest Railway Tunnel Description of the project Prestigious project with highest Gotthard Base Tunnel requirements in terms of railway Altdorf Overall length 57 km technology Altdorf/Rynächt Length 4.4 km t 57 kilometres in length, the A Gotthard Base Tunnel is cur rently Erstfeld the longest railway tunnel in the world. Erstfeld Length 7.8 km It links the Swiss communities of Erst- feld and Bodio. The tunnel forms part Amsteg of the New Railway Link through the Alps (NRLA), which is at present the Amsteg largest construction project in Swit- Length 11.3 km zerland. With the construction of this "project of the century", north/south railway transit trafic will be further Sedrun improved, meaning that transit trafic Sedrun can be moved off the roads and onto Length 9.2 km the railways. More over, travel time for public transport services will be sig- Andermatt niicantly reduced – in conjunction with the Ceneri Base Tunnel which is currently being constructed – (the Faido travel time from Zurich to Milan will be Length 12.9 km cut by one hour), thereby considerably increasing the attractiveness of rail- way travel compared with taking the Ariolo car or plane. In future, passenger and freight trains will pass through the Faido tunnel at speeds of up to 250 km/h. Bodio Length 15.9 km TUNNEL OPEN LINE Gotthard Base Tunnel Postponed Existing railway line Bodio Shaft, adit Biasca Length 7.8 km Exploratory drills Piorasyncline Slab track with LVT system Lines feeding into the tunnel with ballast superstructure The Gotthard Base Tunnel will be construction height compared to a particular environmental conditions opened in 2016 and is a model project ballast superstructure. Of course, are found in the tunnel, such as ambi- that exceeds all previous dimensions great importance is also placed on ent temperatures of up to 40°C and in terms of tunnel length, engineering the topic of safety. For this reason, humidity as high as 70%. Moreover, and logistics. the decision has been made to have strong pressure and suction forces are two separate tunnels (evacuation at work due to the high speed of the There were multiple reasons to concept), permitting access for emer- trains. Similarly, the extremely fre- choose a slab track for the super- gency vehicles if necessary. quent use of the track, with up to 250 structure in the Gotthard Base Tunnel: trains per day, also puts the line under in terms of high availability (due to In order to ensure that superstructure above-average stress. low maintenance outlay), resilience components can be used for a long and longer service life, the slab track time respectively to avoid excessive comes out signiicantly ahead of the stress, a slab track must be itted with conventional ballast superstructure. elastic components – this compen- What is more, with a slab track the sates the lack of ballast elasticity. tunnel cross section can be smaller – meaning a considerable decrease For this prestigious project, the re- in construction costs, as this form quirements in terms of railway tech- of superstructure requires a lower nology were already very high: Pre-assembly The solution with Getzner Elastic insertion pads for sleeper and the slab), the high level of track boots and under sleeper pads accuracy, long service life and reliabil- ity, as well as the low maintenance ll the materials in the Gotthard costs. ABase Tunnel and on the lines leading to the tunnel portals must In addition, all the slab track turnouts provide outstanding performance (manufactured by voestapine-Weichen- over their entire service life. For these systeme GmbH) in the tunnel have been special requirements, Sonneville's supported elastically with Sylodyn® LVT (Low Vibration Track) system was material. Numerous turnouts and indi- selected – one of the world's irst slab vidual track sections with ballast su- track systems. In the case of the LVT perstructure on the main lines feeding system, the track is designed with into the tunnel have also been itted single-block sleepers in rubber boots, with Getzner under sleeper pads. with elastic Sylodyn® insertion pads from Getzner. The unreinforced track Materials for the most stringent is laid directly on the inverted arch. requirements The advantages of this special type of superstructure are that the individual The award of this contract to Getzner is components can be replaced (no rigid primarily due to the excellent material connection between the track panel properties, but also to the company's Concrete single-block Rubber boot LVT system Getzner elastic Sylodyn® insertion pad for sleeper boots Aligned track Measurement technical knowledge and expertise and the LVT projects that have been de- monstrably successful: this system has already proved its worth multiple times and is in successful use on ive continents, with more than 1,000 kilo- metres of track in total. Even in the early stages, within the framework of project planning, the materials were required to withstand tests with high permanent load and also artiicial ageing tests. "Our pro- ducts in slab track systems have now been proving their worth for over 25 years – this is not only conirmed by the test results, but also by multiple well-known references and measure- ments on actual tracks", explains Helmut Bertsch, Project Manager at Getzner Werkstoffe. Getzner calcula- ted the optimum choice of materials and the extent of rail delection of the turnouts using its own "inite element calculation". Sylodyn®, the material used, is a closed cellular elastomer that only has very low dynamic stiffening, even in the high frequency range. Getzner materials have now been successfully used in railway superstructures for more than 40 years – as shown by numerous long-term references. Slab track turnout Increase of track stability Engineering at voestalpine-Weichen- High supply availability and and service life systeme GmbH. optimum quality It is important that all components A conventional ballast superstructure Even if we consider only the particu- fulil the most stringent requirements, with padded monoblock sleepers and lar requirements in terms of quality particularly in case of the high-speed bearers has been installed on the lines and logistics, the Gotthard Base Tun- turnouts in the tunnel: Various types feeding in to the tunnel portals. The nel is an extraordinary project: of highly-elastic Sylodyn® inserts en- Getzner under sleeper pads are used "Getzner had to ensure high supply sure even delection as the train pass- to protect the ballast and extend the availability for the whole duration of es over, along the entire length of the tamping intervals required, as well as the project, and guarantee a consist- turnout and in the transition area the service life of the superstructure. ent extremely high level of quality – between the straight line and the The special elastoplastic material for the entire period of use", explains turnout. properties of the under sleeper pads Anabel Hengelmann, the Chief Execu- result in the ballast embedding into tive Oficer of Sonneville AG. Getzner "High-speed turnouts were developed the padding, thereby increasing the not only provides clients with individ- especially for this project, based on contact surface and reducing the ual support, but also offers attractive, the latest technology. The high re- stress on the ballast. This property professional project support – from quirements placed on the materials has a proven positive effect on track material selection and detailed instal- and in terms of execution represent a stability and the service life of the lation plans to tailor made just-in-time major challenge for all manufactur- superstructure. Moreover, the dynam- deliveries. This project was no differ- ers. Getzner Werkstoffe convinced us ic delection properties of the turn- ent in this respect, being supported with their high-quality materials and outs when a train traverses them have by highly-qualiied Getzner employees excellent international references", been optimised with the aid of in- from the areas of systems develop- explains Erich Wipfler, Director of house "inite element calculations". ment, product management, applica- tion technology, quality assurance and production. Key data for the Gotthard Base Tunnel Client: ARGE Transtec Gotthard Operator: Schweizerische Bundesbahnen (SBB) [Swiss Federal Railways] Builder: AlpTransit Gotthard AG Track engineering: AFTTG Elastic components: Getzner Werkstoffe GmbH, Bürs Slab track system: Low Vibration Track (LVT) from Sonneville AG, Vigier-Rail Planned opening: 2016 Construction time for railway engineering: 2009 – 2016 Length: 114 km – 2 tunnels measuring 57 km each Getzner products: Elastic Sylodyn® insertion pads for sleeper boots, pads for sleepers and bearers for slab track and ballast superstructure, under ballast mats Products installed Elastic Sylodyn® insertion pads for sleeper Tunnel: boots: – 390,000 pcs. for the LVT standard system – 4,000 pcs. for the LVT high attenuation system – for 10 slab track turnouts manufactured by voestalpine-Weichensysteme GmbH Products installed Under sleeper pads for: Feeder track: – 33 pcs. ballast superstructure turnouts