Purpose and Scope of Application
SHRT sleepers with W21 T14 fastenings are designed for use in continuous welded and jointed track with R65 and RT62 rails, without restrictions on traffic density or annual rail temperature variations.
Scope of application:
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tram lines within the city (including near residential areas);
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sections of tram track with asphalt concrete surfacing (maintenance-free fastening), sections with reinforced concrete slab surfacing, and sections without surfacing;
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straight and curved track sections with a radius from 20 m (due to the high resistance of the fastening to lateral loads and the ability to adjust the track gauge).
Key advantages:
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Reliable rail fixing — no need to install track tie rods to stabilise the track gauge.
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High strength and frost resistance — the use of fibre-reinforced concrete prevents cracking.
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Environmental friendliness — no impregnating materials (creosote is not used).
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Reduced construction time — sleepers are supplied with fastenings in a pre-assembled state.
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Repairability — all fastening components, including dowels, are replaceable.
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Corrosion protection — metal parts are zinc-lamella coated.
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Vibro-acoustic comfort — reduced noise and vibration levels during operation.
The design features of the W21 T14 fastening ensure:
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uniform load distribution;
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reduction of dynamic forces during the passage of rolling stock;
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effective energy dissipation in the 500–2000 Hz range — these are the frequencies perceived by the human ear as “rumble”;
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reduction of structural noise levels by up to 3–6 dBA compared to rigid anchor systems.
This is achieved through:
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Elastic travel of the SKL21 clamp — 14.5 mm (versus 10–12 mm for analogues).
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Loss factor of a single fastening assembly — η = 0.25 (high damping).
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Optimal assembly stiffness — ~60 kN/mm, which provides soft primary decoupling of the rail from the sleeper and reduces vibration.
Road transport data
When transporting sleepers by road (vehicles with side-unloading capability are recommended), stacks of 20–30 sleepers are used, with 5 sleepers per row (i.e. 4–6 rows).
Road transport shipping norms:
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up to 97 sleepers with fastenings (for a vehicle payload of 20 tonnes);
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up to 116 sleepers with fastenings (for a vehicle payload of 24 tonnes).
