News

HFA-Projekt

HFA-Projekt: Suche nach möglichen Alternativen für Kreosot zur Imprägnierung von Bahnschwellen aus Holz

Die Holzforschung Austria (HFA) betreut das Forschungsprojekt „Bahnschwelle 2020“. Ziel ist es, Alternativen für das derzeit wegen der guten Langzeiterfahrungen noch unverzichtbare Schutzmittel Kreosot (Steinkohlenteeröl) zur Imprägnierung von Bahnschwellen aus Holz zu finden.

Read more …

Areas where wooden sleepers are used today

Reports by A. Terouin (Geneva) from the year 1960 show that in the year 1958, of the approx. 681 million sleepers present in the tracks of European railways (not including USSR), roughly 85% (i.e. 585 million) were wooden sleepers.

Wooden sleepers continue to be used around the world in track construction and are used today as track, switch, tunnel and bridge sleepers in European and non-European state railways, in industrial and dock railways, private and branch lines, in light rail traffic (rapid transit and underground railways), and mountain, narrow-gauge and tourist railways.

However, along with concrete sleepers, steel sleepers and other bearing elements, the proportion of wooden sleepers in European and non-European countries varies.

Because of its favourable properties with respect to vibration and noise nuisance, without any misgivings and without any disadvantages the wooden sleeper can be put to use at a line speed of <160 km/h, even in state railways and long distance traffic.

Because of their outstanding properties, wooden sleepers are predestined in particular for use in industrial, dock and shunting areas. For any possible special needs they can be easily worked, planed, and for custom track gauges, drilled, and if necessary also milled.

In shunting areas derailment often occurs where the wooden sleepers are only slightly damaged, and experience no breakage, because the wooden sleeper is less susceptible to breakage and very robust because of its elasticity. Should in isolated instances a sleeper become totally destroyed, the replacement of a single sleeper is simple and easy to do.

Concerning the use of wooden sleepers in private and branch lines, no discussion is required. They are considerably lighter to handle and lay than concrete sleepers.

In mountain railways the wooden sleeper has its particularly useful advantages, because of the sharp curves and radii. Easy handling, smaller amounts of space and ballast required, individual track gauges and inclinations.

In the area of underground railways, because of their low weight, wooden sleepers can be easily transported, placed in the shafts or tunnels, and easily moved with and without machinery. Because of their properties they enable calm, low-vibration and noise-insulated driving on the tracks.

Moreover, it can be assumed that the generated noise is perceived by the human ear as more pleasant and less disruptive.

Especially on isolated stretches of track, because of their strong resistance to electrical conductivity wooden sleepers have major advantages, avoiding the need for expensive and additional measures.

All of the good properties of the wooden sleeper that apply for underground railways also apply for the area of tunnels.

Despite the environmentally friendly kinds of impregnation that are possible today, in the area of bridges well-dried oak bridge sleepers can be used even without impregnation. They are easy to cut into a slightly wedged shape for banks, and for various bearing elements they are easy to mill and machine.

Turnout sleepers made of wood still have no cheap and efficient competitor. Because of their considerably lower weight compared to turnout sleepers made of concrete, easy handling and laying in place on location is a great advantage.

For more complicated track switching constructions the necessary lengths of sleepers are easy to custom drill for all types of fastening elements, and if desired, easy to plane along the entire upper bearing.