Urban planners are obliged to expand local public transport and railway systems to cope with the rapid development of urban spaces. Long term durability, electrical resistance and low maintenance are essential. There is also an increase in requirements for reduced vibration and noise in the rail fastening system, making flexible, volume-compressible grout materials an effective solution.

Systems Plus Knowhow

Fixing tram rail wiht epoxy grouting


Sika provides technical support in each stage of railway installation projects to consultants, operators and contractors.

Sika’s optimum, innovative rail track installation solutions endure a wide variety of exposures and conditions for maximum axel loads up to 25 tons.

Types of Rail Fixing & Grout

Depending on the design, the rail track is supported by means of an elastic support point with discrete fixation or a continuous rail base with embedded rails. Click on each type below to learn more.

Illustration of discrete fixation rail track for rail fixing grout and anchoring
Illustration of embedded rail track for rail fixing grout and joint sealant

1. Discrete Fixation Rail Track

Close up view of discrete rail fixation for train track on Oborniki Bridge in Poland

With discrete fixation, the rail track is mounted onto baseplates fastened to the ground at various intervals depending on the loads.

Sika provides grout and chemical anchoring for discrete fixation of rail tracks.

Click on the image below to learn more.

Rail fixing train track tunnel
Rail fixing anchors

Since this rail fixing system is based on chemical and mechanical compounds, no pre-loading stress is imparted to the substrate as it is with expansive mechanical anchors. It is ideally suited for high load applications, especially in the case of discrete fixation.

Sika provides three options of chemical anchoring materials:
Sikadur® 32+ (dry and matt damp concrete substrates) - pourable
Sika AnchorFix®-3030 (dry and matt damp concrete substrates) - applied with the application dispenser
Sika Icosit® KC 220 / 60TX (dry concrete substrate) - pourable

Rail fixing grouts

Regardless of the type and size of baseplates, pourable flexible grout can be used for all situations of direct fixation - ballast-less tracks, special track work, tracks in tunnels and on bridges and under certain circumstances, even those without anchor bolts.

Sika provides discrete fixation grouts for various conditions:

  • Icosit® KC 340/4 is used for discrete fixation with max product service load up to 3 MPa.
  • Icosit® KC 340/7 is used for discrete fixation with max product service load up to 4 MPa. The versatility of those products allows its use for any kind of steel baseplates, anchor bolts and rails.  

2. Continuous, Embedded Rail Track

Rail fixing tram track embedded into cobblestone street in Zurich, Switzerland

With continuous under-sealing or embedded rail fixation, the rail track is recessed into the substrate, creating a continuous, uninterrupted rail line. This is commonly used for urban tram tracks.

Sika provides grout, elastic joint sealing and adhesive material for embedded rail tracks.

Click on the image below to learn more.

Workers installing rail fixing grout in tram depot in Oerlikon, Switzerland
Rail fixing grouts

Sika provides embedded rail fixation grouts for various conditions:

  • Icosit® KC 340 / 35 - maximum product service loads up to 1 MPa
  • Icosit® KC 340 / 45 - maximum product service loads up to 2 MPa
  • Icosit® KC 340 / 65 - maximum product service loads up to 4 MPa
Adhesives for filler blocks

Sika provides adhesive materials for fixing filler blocks:

  • Icosit® KC 330 FK Fast-setting, two-component thixotropic (sag-resistant) flexible polymer based on polyurethane material
  • SikaBond®-139 Filler Block applied with the application dispenser
Joint sealing

Sika provides elastic joint sealing between rails and adjacent surfaces:

  • Sikaflex®-406 KC One-component, self-leveling, booster-accelerated elastic joint sealant with high mechanical and chemical resistance; especially designed for joints between rails, adjacent surfaces (asphalt) and use with Icosit® KC products
  • Sikadur®-32+ Two-component primer for concrete (dry and matt damp concrete substrates) and steel; based on a combination of epoxy resins and special fillers, moisture tolerant, designed for use at temperatures between +10 °C and +30 °C; surface resistance of Sikadur®-32+ coating (4,335 GΩ) meets requirements of EN 50122-2 standard (0,8-8,8 GΩ)
  • Icosit® KC 330 (Sika  Primer-115) One-component, ready-to-use primer for dry concrete and steel substrates

Why Icosit® KC Flexible, Polyurethane Grouts for Rail Fixing

Sika’s Icosit® KC 340 polymer resin grout products are made of a flexible, two-part polyurethane. They are insensitive to moisture and designed as a vibration-absorbing, load-bearing, flexible grout for discrete fixation, continuous undersealing or embedding rails.

The Icosit® KC range has won worldwide recognition for tailor-made, long-lasting direct fixation of rails to solid substrates such as concrete and steel. They are incorporated into a variety of trackwork designs - in discrete and continuous fixation, embedded or floating rail, lawn tracks, for railway, light rail, tram tracks and crane track installations.

Silent, Smooth Tracks for a Peaceful Urban Experience

Rail fixing tram moving fast through Bahnhofstrasse street at night in Zurich, Switzerland
Effective noise and vibration reduction
  • Resilient intermediate layer for optimum reduction of noise and vibration transmission, i.e. vibration damping, cast-in-situ after alignment to eliminate voids under the rail and to ensure continuous and homogenous fixation
  • Increase comfort and smooth train operation, also known as "silent tracks"
  • Appropriate selected Shore A hardness for a given type of rolling stock ensures primary noise reduction by reducing vibrations and secondary noise, increasing the comfort and smooth running of the train, allowing it to meet noise standards requirements. This feature also ensures the right level of rail deflection.


Sika’s Flexible PU Rail Grouts – All-Around Advantages

Black vector icon piggy bank with money



High Durability & Low Maintenance Costs
How Can It Be?
  • Load bearing - resistant to dynamic loads and permanent alignment of rails ensuring track stability
  • Leveling out inevitable tolerances between rail and concrete or steel substrate
  • Long-term resistance against water and most detergents allows the long service life of applied solution in wash train stations
  • Short-term (minimum 3 days) resistance against: mineral oils, diesel, fuel, vegetable and animal fat; allows the long service life of applied solution in the case of tracks integrated with road surface
  • Extremely low (close to zero) maintenance costs and long service life, thanks to the above points
Black vector icon versatility cross arrows pointing in all 4 directions



Why Is It?
  • Suitable for any kind of rails (e.g. 60R1, 60R2, 49E1, etc.).
  • Has selected versions of materials for concrete and steel substrates, depending on the application (tram, train, underground and overhead, etc.)
Black vector icon engineer man head with hard hat tie



Increased Safety with Low Risk
Tell Me More
  • Added safety and maximum performance due to excellent parameters of Sika Icosit® KC products
  • Highly efficient electrical resistivity for prevention of stray current leakage to safeguard against signalling malfunction
Black vector icon chart gears efficiency



Easy Application
How So?
  • Manually apply, or
  • Machine apply – highly ecological and economical solution due to reduced waste and less application time needed  

Certified Quality Provides Security

Before being released, the products of the Icosit® KC series have to undergo extensive in-house testing using sophisticated equipment under realistic conditions.

In addition to that, large scale field tests are complemented by independent, third-party testing facilities, such as the Technical University of Munich, the University of Calgary (Canada), AEA Rail Technology (UK), the University of Louvain (Belgium), the University of Györ (Hungary) and many others. German Railways (DB) ranked Sika as "Q1", meaning top quality supplier. Many other railway authorities also rely on the approved track fixing designs with flexible grout from the Icosit® KC series.

To supplement test reports with long-term in-field experience, a perfectly intact 28-year-old discrete, direct fixation with Icosit® KC grout was removed from the Heinrichsheim bridge in Bavaria, Germany. The Technical University of Munich produced a load deflection (spring) diagram. In comparison with the corresponding diagram from the quality control at the time of installation in 1971, it only showed a loss of flexibility of 6% (+/- 10% production tolerance) after 28 years - proof of outstanding longevity.

Blue test book from Technical University of Munich for rail fixing
Image: Test book from the Technical University of Munich
"Trustful systems can stand the test."
Testing equipment for Sika Icosit rail fixing
Image: Sika Icosit® KC products undergo extensive in-house testing
Testing equipment for Sika Icosit rail fixing

Sika’s Experts Provide Assistance to Benefit your Business

World Map

Local Contact

Contact a Sika expert near you for technical support and locally available products and systems.

Global Project Support

Sika’s Project Support Team provides in-depth consultative support for our full product range and represents a single point of contact into the extensive Sika network of experts. Please contact us to learn more or inquire specifically on your current project(s).