How to Use Railroad Cross Ties for Driveway Borders is part of a series on how to use railroad ties.
A railroad tie is a rectangular support for the rails in the railroad tracks.Ties transfer loads to the track and hold the rails upright to keep them in the correct gauge.
Railroad ties are usually made of wood, but prestressed concrete is more popular in Europe and Asia.Steel ties and plastic ties are used on secondary lines in the UK, but not as much as wood or concrete.The market share for traditional and wood ties in North America was 91.5% as of January 2008.[3]
The mainline railroad has a crosstie spacing of 19 to 19.5 inches (48 to 50 cm) for wood ties or 24 to 61 cm for concrete ties.There are 3,250 wooden crossties per mile or 40 ties per 65 feet for wood ties.In the US, rails can be fastened to the tie by a railroad spike, with iron/steel baseplates screwed to it and secured with a proprietary fastening system.
The chairs holding the rails were fixed to the stone blocks that were laid into the ground.The method of construction allowed horses to tread the middle path without the risk of tripping.It was found that it was difficult to maintain the correct gauge in railway use.The stone blocks were unsuitable for soft ground, such as at Chat Moss, where timber ties had to be used.Bi-block ties with a tie rod are very similar.
At least two flat sides were achieved with axe ties, which were made by hewing with an axe.Oak, jarrah and karri are popular hardwoods and are difficult to get from sustainable sources.While they have the advantage of accepting treatment more readily, some lines use Douglas fir, which is cheaper, lighter and easier to handle.Softwood is treated and creosote is the most common preservative for railway ties.Preservatives such as copper azole or micronized copper can be used.Major US railroads are using new wood preserving technology in order to extend the life of wood ties in wet areas.Some timbers, such as sal, mora, jarrah or azobé, can be treated.[8]
There are many problems with wooden ties, including rot, splitting, insect invasion, plate-cutting, and spike-pull.As wooden ties age, they develop cracks that allow sparks to lodge and start fires.
It is cheaper and easier to get a concrete tie than a timber one.When installed with continuous-welded rail, their greater weight ensures improved retention of track geometry.Due to their greater weight, concrete ties have a longer service life and require less maintenance than timber, which helps them remain in the correct position longer.To perform well, concrete ties need to be installed on a subgrade with enough depth on free-draining ballast.Wooden ties are often used in densely populated areas.
Pre-stressed concrete ties are the only ones allowed on the highest categories of line in the UK.
Due to the longer life and lower cost of concrete bearers compared to timber, most European railways now use them in switches and crossing layouts.
Steel ties are formed from pressed steel.The ends of the tie are shaped to form a "spade".The upper surface of the tie is welded to housings to accommodate the fastening system.Due to their ability to be installed on the existing ballast bed, steel ties are now in widespread use on secondary or lower-speed lines in the UK.Steel ties are lighter in weight than concrete and can be stacked in small bundles.Steel ties can be installed onto the existing ballast, unlike concrete ties which need a full depth of new ballast.Steel ties are 100% recyclable and require up to 60% less ballast than concrete ties and 45% less than wood ties.
Steel ties have suffered from poor design and increased traffic loads in the past.These designs are often obsolete and limited in load and speed capacity but can still be found in many locations around the world.There are many steel ties with over 50 years of service that can be rehabilitated and still perform well.The Hejaz Railway in the Arabian Peninsula had an ongoing problem with Bedouins who would steal wooden ties for campfires.[9]
Modern steel ties have a proven record of handling heavy loads and adverse track conditions.Railroad companies value the fact that steel ties are more economical to install in new construction than wood ties and concrete ties.Steel ties are used in almost all sectors of the worldwide railroad systems, including heavy-haul, class 1s, regional, shortlines, mining, and all manner of industries.Over the last few decades, steel ties have proven to be beneficial in turnouts and provide the solution to the ever-growing problem of long timber ties.
Steel ties may be used with track integrity systems if they are insulated.Without insulation, steel ties can only be used on lines with no block signaling or level crossing.
A number of companies are selling railroad ties made from recycled plastic and recycled rubber.The ties are impervious to rot and insect attack and can be modified with a special relief on the bottom to provide additional stability, according to the manufacturers.The hybrid plastic tie has a design that is completely surrounded by ballast in some main track applications.
Plastic ties are usually replaced with timber ties soaked in creosote, which is a toxic chemical, because of the environmental benefits.Other rail applications include underground mining operations, industrial zones, humid environments and densely populated areas.Railroad ties are partly exchanged with rotten wooden ties, which will result in continuous track stiffness.The benefits of hybrid plastic ties and composite ties include better distribution of forces and reduction of vibrations into bridge girders or the ballast.The sound production will be decreased due to the better damping properties of hybrid plastic ties.Network Rail replaced wooden ties with recycled plastic in 2009.In October 2012 I-Plas became insolvent.[18]
In 2012 New Zealand ordered a trial batches of " EcoTrax" brand recycled ties from Axion for use on turnouts and bridges, but then the company filed for bankruptcy in 2015.The ties were developed by Dr. Nosker at Rutgers University.[ 24]
The Y-shaped tie was first developed in 1983.Due to the load spreading characteristics of the Y-tie, the volume of ballast required is reduced.The resistance to track movement is very good despite the high noise levels.An exact geometric fit cannot be observed with a fixed attachment point because of the three-point contact of a Y steel tie.
Most of the Y-tie track has been built in Germany.[26]
The ZSX Twin tie is a pair of pre-stressed concrete ties that are longitudinally connected by four steel rods.The design is said to be suitable for track with sharp curves, track subject to temperature stress, and as a transition track between traditional track and slab track.30
Concrete monoblock ties can also be produced in a wider form.There is no ballast between the ties, so a wide tie increases resistance and reduces pressure.In Germany, wide ties have also been used in conjunction with the GETRAC A3 track systems.35 and 36 were the days.
Two concrete rail supports are joined by a steel bar.The advantages include increased resistance and lower weight than monobloc concrete ties, as well as elimination of damage from torsional forces on the ties center due to the more flexible steel connections.In France, this tie type is used on the high-speed TGV lines.Bi-block ties are used in track systems.The gauge is convertible by cutting bar and welding extra bar.
The frame ties are made from a single concrete casting.The Austrian system uses this system in which the track is fastened at the four corners of the frame.The frames are butted close to each other.The advantages of this system over conventional cross increased.Construction methods for this type of track are similar to those used for conventional track.40
Ties are laid parallel to the rails in the ladder track.The longitudinal ties are similar to Brunel's baulk track and can be used with or without a support.
There are many ways to fix the rail to the railroad ties.When spikes gave way to cast iron chairs, springs were used to fix the rail to the tie chair.
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