Freight traffic places immense demands on the superstructure. High axle loads combined with poorly maintained freight wagons with little suspension lead to considerable dynamic loads, which have to be absorbed by the concrete sleepers in particular. Axle loads of 30 tons and more therefore require a much more robust sleeper design than conventional tracks. RAILONE has risen to this challenge and today has heavy-duty sleepers for American freight traffic as well as for ore and coal transportation in Europe and the Middle East.