In addition to the application of road markings, we frequently have to remove existing markings in advance of the application of new road markings where a client has designed a new road traffic layout.
The complete removal of a durable road marking from any surface is difficult without causing damage to the road surface.
We have determined from over 35 years of experience of road marking removal that no single method exists that will work equally well on the wide variety of available marking materials used on varied pavement surfaces. Effective results can often be achieved through the utilisation of a combination of removal techniques.
Issues to consider when selecting a removal technique are as follows;
- Quantity of Road Markings to be removed?
- Is the surface a temporary or permanent surface?
- Do you require full or partial removal of the road marking?
- What space is available for equipment access?
- Time of day/night when the work will be carried out?
- Proximity of houses to the work site?
- Do you require a temporary or permanent removal solution?
We currently provide 4 Road Marking removal techniques:
HOT COMPRESSED AIR LANCE
Hot compressed air lances use a mixture of propane gas and compressed air to produce a concentrated, powerful, high velocity flame that will vaporise the road marking. The temperatures involved are likely to cause damage to the road surface and, for this reason, the equipment is inappropriate for use on thin surfaces. Noise, smoke and fumes are also important issues that need consideration. The H.C.A. lance operates at a relatively high noise level (115 dB(A)) and its appropriateness close to other site operations and urban areas must therefore be assessed. The vaporised thermoplastic can cause clouds of smoke which may affect drivers’ visibility.
MECHANICAL SCABBLING
- Scabbling is achieved by the motorised, high speed rotation of hardened steel or tungsten carbide cutters. Settings to pressure on the cutter head and the depth of scabbling can be adjusted during operation to achieve satisfactory results.Our range of scabblers include;
- Pedestrian scabblers
- Self-propelled scabblers
- Skid Steer mounted surface preparation units.
Mechanical scabbling grinds the marking from the surface, but total removal is not possible without damaging the surface. Small amounts of marking are left in the voids of the surface and this residue has to be masked or removed by other methods. The main use of mechanical scabbling is for removing the bulk of markings and the removal of raised ribline markings which are exceptionally thick. This method produces large amounts of debris that must be cleaned up quickly to avoid the thermoplastic particles re-adhering to the surface.
Mechanical scabbling is ideal for use on temporary surfaces or for the partial removal of existing road markings as a surface preparation technique prior to the application of a new road marking. The resulting surface texture from the mechanical scabbler will help provide a good key for the new road marking.
For high volume works we use a skid steer/scabbler followed by a truck mounted road sweeper to remove the debris generated from the scabbling operations.
UHP WATER JETTING
Highway Markings introduced UHP Water Jetting to Ireland in 2005 as a road marking removal technique. It is now the preferred road marking removal technique by Local Authorities and the National Roads Authority.
UHP Water Blasting quickly removes markings faster and more thoroughly than abrasive methods – without damaging the pavement or asphalt. UHP Water blasting is fast and productive, and avoids exposing the environment to chemicals or contaminants. It also simplifies clean up, is dustless and leaves a clean surface.
UHP Water Jetting uses water pressurised by an extremely powerful motor/pump to clean and remove markings from the pavement surface. These powerful motors can deliver pressure at the cleaning head of up to 40,000 psi (2,700 bar). The sheer force of the water delivered literally knocks the markings off the pavement. A vacuum recovery system removes all waste materials and surplus water leaving the road surface semi-dry.
Our UHP Water Blasting units are mounted on 26 tonne trucks and uses 22 to 40 litres of water per minute.
In the hands of our skilled and experienced operators, this process is capable of removing all kinds of road marking products without damaging the road surface. Our equipment is fitted with full dual controls thereby ensuring that all works are carried out in the same direction as the traffic flow. Our operators have received training from the UK Water Jetting Association. Operatives are not required within the ‘Works Area’. Positive control of traffic allows ‘sideways clearance’ to be at a minimum and, in most instances; a semi static traffic management system is used.
The cleanliness of our UHP Water Jetting Removal System makes it a positive contributor to a healthier environment.
The advantages of using UHP Water Jetting include:
- No chemicals, additives or abrasive materials are used
- No fumes, smoke or dust is generated
- Noise levels are considerably lower than alternative road marking removal techniques
- Suitable for use on all types of road surfacing materials
- Operates with traffic flow
- No personnel required to work on the carriageway
- Self contained unit complete with debris vacuum recovery
- Minimal surface impact
TEMPORARY BLACK PREFORMED TAPE
Removable preformed black tape is designed to provide a short-term obliteration of pavement markings. It offers a fast way to create temporary lane changes during road maintenance and on construction sites. The traffic flow can be restored to normal when required by simply removing the black tape to reveal the original markings. Good weather conditions are required to enable the tape to bond to the markings.
Temporary tape adheres to the road surface by a waterproof seal with the carriageway. If this seal is penetrated by water, the adhesion fails. The road surface must be dry, clean, free from salt, and the ambient temperature needs to be above 5oC. Temporary tape does not perform well on open textured surfaces in wet conditions when water can flow through the surface and a pumping action causes the tape to lift.
