Runway Resurfacing and Repairing Using Modern Materials and Techniques
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Transcript of Runway Resurfacing and Repairing Using Modern Materials and Techniques
Runway Resurfacing and Repairing Using Modern Materials and Techniques Seminar Report 2012-2013
1.INTRODUCTION
The transport modes like roadway, waterway and airway have
been used by the mankind using land, water and air. In the past railways were
assigned priority of developments, Because it was one mode of transport,
which helped mass transportation of goods and passengers. Railways and
roadways in India and abroad are in competition today for providing better
transportation facilities. Air transportation is the most suitable transportation
technique for long distance travels. So runway has very importance. Runway
is a long and comparatively narrow strip, which is paved for small
aerodromes.
Repair and resurfacing of runway is a complex activity, which
requires comprehensive engineering evaluation, selection of suitable materials
commensurate to problems and proper co-ordination of construction procedure
and activities .It also demands setting up adequate quality planes and quality
assurance methods. For runway resurfacing it is required to determine the
nature and extend of deterioration and also the causes of deterioration. For this
it is essential to carry out detailed study including overall projection
evaluation so as to evolve suitable repair alternatives.
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2. The Pavement Classification Number- Runway Strength Rating and Load Control System.
The Air craft Classification Number/ Pavement Classification Number
(CAN/PCN) system has been adopted by ICAO as the standard for the
international reporting of air field pavement bearing strengths .The ACN-
PCN system of rating air port pavements is designated by the international
civil aviation organization (ICAO) as the only approved method for reporting
strength. The ACN- PCN method came in to use in1981.
The ACN- PCN system is simple to use. Each air craft is assigned a
number that expresses the structural effect on a pavement for a specified
pavement type and a sub grade category. Each air port operating authority
reports site pavement strengths using the same numbering system. The
pavement is capable of accommodating unrestricted operations provide the air
craft load number is less than or equal to the pavement strength number.
Maximum tire pressure limitations may also be applied to some pavements
which may further restrict certain air craft operations. The ACN is based on
static application on aircraft loads to the pavement surface making them
somewhat conservative in nature
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The ACN and PCN are defined as follows:
• ACN is a number that expresses the relative structural effect of an
aircraft on different pavement types for specified sub grade strengths
in terms of a standard single wheel load
• PCN is a number that expresses the relative load carrying capacity of
a pavement in terms of a standard single wheel load
• The system is structured so that a pavement with a particular PCN
value can support, without weight restrictions ,an aircraft that has an
ACN value equal to or less than the pavements PCN value
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Runway Resurfacing and Repairing Using Modern Materials and Techniques Seminar Report 2012-2013
3. ASPHALT APPLICATIONS
3.1 Airfield uses of asphalt
Most of the world’s paved roads are surfaced with asphalt, Asphalt is
obtained by fractional distillation of petroleum crude, which gives good
performance and durability under the most heavily trafficked conditions.
Asphalt is obtained by fractional distillation of petroleum crude. These
materials are also widely used in the construction of hard standing and parking
areas for both light and heavy vehicles. They are therefore eminently suitable
for use in the construction and surfacing of access roads, perimeter roads and
vehicle parking areas on airfields.
Without hard paving, access may be difficult to the airfield, flying may
be restricted in inclement weather or the facilities may not come up to the
minimum standards required by the regulatory authorities for passenger
carrying aircraft. The following areas on a typical airfield are likely to
require hard paving:-
• runways
• taxi-ways providing access to runways
• aircraft parking, re-fuelling or servicing aprons
• hanger floors
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Runway Resurfacing and Repairing Using Modern Materials and Techniques Seminar Report 2012-2013
• car, bus or commercial vehicle parking areas
• access roads
• edge drainage (French Drains) for runways and taxiways
In each of these areas different considerations apply. For example,
runways require good skid resistance and surface water drainage for good
braking, an even surface regularity to ensure passenger comfort and minimum
risk of damage to delicate electronic components and adequate strength to
support the high wheel-loadings of modern aircraft. Where jet-engined aircraft
operate, freedom from loose particles is an additional, essential requirement to
avoid the expensive damage that can be caused to jet-engines from ingestion
of foreign objects (known as Foreign Object Damage or FOD). This term may
also be used for “Foreign Object Debris” when referring to any detritus or
loose particles on or near to runways or taxiways.
For aircraft parking areas the main requirement is adequate stability
under high wheel-loadings; for paved areas where aircraft will undergo re-
fuelling and servicing, the principal considerations are adequate stability under
wheel-loads and heavy point loads from maintenance machinery as well as
good resistance to oil spillage
Runways need to be constructed with sufficient strength to carry the
moving aircraft. Runways require a higher degree of resistance to skidding
and aquaplaning in view of the higher speeds involved. One means of
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Runway Resurfacing and Repairing Using Modern Materials and Techniques Seminar Report 2012-2013
achieving the latter, now employed on many major runways in the UK, is to
use an open-graded Porous Asphalt surface course traditionally known as
Porous Friction Course as the running surfacing. This acts as a drainage layer
to prevent surface water adversely affecting aircraft tire grip on the surfacing
in wet weather.
Beneath the Porous Friction Course a strong impervious binder course
of Hot Rolled Asphalt or a dense Asphalt Concrete known as Marshall
Asphalt is required laid to adequate falls. Alternatively the new surface course
may be laid directly on an impervious existing surfacing.
When resurfacing work is being undertaken on runways, it is essential
that the existing surfacing is of good regularity and laid to adequate falls or the
levels are corrected by applying an appropriate regulating layer. This is of
particular importance if a Porous Friction Course is to be applied and ensures
that water is not held in the new surfacing to lead to heavy ice formation in
winter.
Where relatively light aircraft are involved standard road surfacing
materials, namely Hot Rolled Asphalt, close-graded/dense Asphalt Concrete
or Stone Mastic Asphalt specified using the guidance from PD 66911 and the
appropriate European Asphalt Standard will provide good durability and
adequate performance. If Hot Rolled Asphalt is employed, a 35% stone
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content mix without the application of pre-coated chippings should give good
performance and durability
3.2 MODERN ASPHALTS
Most runway resurfacing is carried out at night, with contractors
given access for just a few hours. They do the work in short bursts, completing
a section each night and reopening it the next day. It is not surprising, given
these constraints, that designers and contractors tend to stick with tried and
tested mixes for the new runway surface – usually Marshall Asphalt, a
continuous graded aggregate mix that gives a harder surface than traditional
hot rolled mixes.
Nynas has, over the years, developed a number of products that can be
used in runway surfacing and other heavily trafficked areas within airports.
These include binders with high resistance to damage by fuel oils and de-icing
fluids – a major issue for airport managers – as well as binders for thin
surfacing and foam mixes.
One fuel damage resisting product Nyguard , was used at Bristol
Airport to bring two redundant runways back into use as taxiways and for
aircraft refueling and parking(fig.1). These ancillary areas are seen as lower
risk.
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Runway Resurfacing and Repairing Using Modern Materials and Techniques Seminar Report 2012-2013
Fig.1 Nyguard, was used at Bristol airport to bring two redundant runways back in to use
Nynas has developed the product further to produce Nyguard
HR(fig.2), a hot mix binder specifically designed for heavy duty areas like
airfields, docks and bus bays. As well as its fuel damage resisting properties,
the binder gives cohesion values up to five times greater than equivalent
paving grade bitumen, making it much more resistant to shearing forces and
resulting scuffing, tearing and deformation.
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Fig.2 Nyguard HR, a hot mix binder specifically design for heavy duty areas
One issue that may make airport owners more willing to look at
non-traditional mixes for runways is sustainability. With local authorities
setting targets for recycling, and commercial firms increasingly aware of
waste and energy consumption, there is increasing pressure to reuse material
in runway resurfacing.
In a recent contract at Liverpool Airport, Tarmac reused runway
planings for sections of recycled pavement. These areas – the outer strips of
the runway – were re-constructed using Nyfoam, a binder specifically
developed by Nynas for foam mixes and used last year on the UK’s largest
road recycling contract on the A38 in Devon.
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The successful application of the technique at Liverpool is likely
to lead to other airports considering recycling for future resurfacing projects.
While Nynas’ specialist products have so far mainly been used
on ancillary areas, such as taxiways and parking bays, the company also has
experience of supplying specialist materials for main runways. At Exeter
Airport, for example, its Nypol TS polymer modified binder was used by
Bardon in the construction of a “Super AirMat” runway – a thin surfacing
alternative to traditional Marshall Asphalt.
Super AirMat contains a 10mm nominally sized grit-stone with a
very high polished stone value to give the surfacing a high level of grip. The
Nypol TS is designed to give good adhesion and cohesion with the stone, and
extra durability comes from adding cellulose fibres to the asphalt mix.
The Super AirMat mix was designed specifically for airfields,
and is laid in a single pass, making it a very efficient way to surface large
areas in a relatively short time.
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Runway Resurfacing and Repairing Using Modern Materials and Techniques Seminar Report 2012-2013
4. Rubber Removal Techniques
The most common methods of pavement retexturing are:
• High Water Pressure,
• Ultra High Water Pressure (Track Jet),
• Chemical,
• Shot Blasting,
• Mechanical Process.
4.1 High Pressure Water blasting (HPW)
Rubber is removed by means of rotary devices that move along
the surface as it cleans. This is done utilizing up to 30 gallons of water per
minute at pressures of between 100 to 1,000 bar . The water that penetrates the
surface effectively cleaning rubber deposits creates an hydraulic effect. This
helps to increase the frictional values and surface texture of the pavement. A
combined suction part or a sweeper that picks up the rubber debris during its
operations usually accompanies it. This allows for the pavement to be easily
and quickly returned to operations and is especially advantageous in airport
operations where time constraints and short possession time is common.
Benefits of using this technique are:
• The speed at which rubber is removed (1,200 m² per hour are claimed).
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Runway Resurfacing and Repairing Using Modern Materials and Techniques Seminar Report 2012-2013
• The cost efficiency of the process (water is generally provided).
• The improved friction characteristics of the pavement due to penetration
of the water and the removal of rubber.
• The ease of getting off the runway in the event of an emergency.
• Its usage is independent of weather and can be operated in cold, damp
wintry conditions.
Disadvantages are:
• Noise from the operation requires the wearing of hearing protection.
• Eye protection should also be worn in the vicinity of the machine while
in operation.
• Appropriate disposal of waste material is required.
• Does loosen surface matrix encouraging the loss of fine materials.
• Cleaning rate is 70% with one run.
• Heavily damages certain asphalt types like antiskid.
• Damages grooves and pavement surfaces over time (8 years).
• Damages sealing.
• Cannot be used to clean AGL.
HPW is most effective on sprayed seals and asphalts that show loss of
texture due to flushed bitumen. This results in safer operating conditions for
pavements.
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Runway Resurfacing and Repairing Using Modern Materials and Techniques Seminar Report 2012-2013
4.2 TrackJet (Ultra High-Pressure Water blasting)
The TrackJet, an Ultra High-Pressure Water blasting machine
developed by Bernd Weigel in Germany, is widely used at BAA airports and
other leading airports in Europe, as well as European highways for retexturing
and paint marker removal.
Through its modern technology of retexturing, this machine has
consistently removed 100% of rubber build-up and pavement markings from
pavements without touching the pavement micro or macro texture. It utilises a
nozzle system that is truck mounted, applying very little water at very high
pressure through a unique computer-controlled system.
This enables an environmentally friendly and most effective
maintenance for all kind of surfaces. Cost savings through increasing rubber
removal intervals without damaging or destroying the aggregates on the
pavement surface result in an increased pavement life.
Benefits of this technology are:
• Optimum treatment with care of pavement surface.
• Reduces direct and indirect renovation cost by prolonging cleaning and
resurfacing cycles.
• Applicable to all kinds of surfaces; for example asphalt, anti-skid, petro-
grip and concrete.
• Best possible friction values, therefore prolongs the time interval till
next cleaning.
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Runway Resurfacing and Repairing Using Modern Materials and Techniques Seminar Report 2012-2013
• High environmental compatibility is reached due to very low water
consumption and very low eroded road/runway substance volume.
• No damage to grooving, runway lighting systems, marker paints and
joint sealing.
• Clearing out of expansion joints.
• Only needs one personnel to operate.
• The ease of getting off the runway in the event of an emergency;
runway can be evacuated in 3 minutes leaving the working area tidy and
surface like new.
• Its usage is independent of weather and can be operated in cold, damp
wintry conditions or warm temperatures (2 to 40 degrees centigrade).
• High environmental care due to extremely low water and fuel
consumption; the Track Jet works with clean water without chemical
adhesives and requires only 10 to 20% of the water and 30% of the fuel
HPW systems normally require.
• Low expenses with waste removal, because no chemical is used to
separate the rubber waste from waste water.
This system is also universally suitable for cleaning sealing joints, concrete
renovation, cleaning of steel and concrete areas, apron areas and oil spill
removal.
Disadvantage of systems:
• Appropriate disposal of waste material is required.
• Some airport staff claims that up to 800 m² per hour cleaning (but 100%
rubber removed) is too little.
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Various equipments used for water jet system are shown in figures
Fig.3 SUPRA SNOW REMOVAL VEHICLE
Fig.4 UNIMOG 400 L FOR WATERJET SYSTEM
Fig.5 EQUIPMENT FOR WATERJET SYSTEM
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4.3 Chemicals
Environmentally friendly chemicals have been developed that
are safe and effective in cleaning rubber from contaminated surfaces. This is
done by spraying the chemicals onto the pavement surface and then scrubbing,
brushing and working them into the rubber deposit over several hours. The
chemicals break down the polymerized rubber into a soft jelly like substance.
The substance is then flushed off the runway by water blasting
when the process is completed. During this process, the runway cannot be
reopened until the process is completed due to the runway surface being
slippery.
The debris cannot be swept up using conventional sweepers
since the chemicals will react with the rubber seals within the sweeper. Even
though the debris is considered to be biodegradable, the chemical is not and as
a result, the usual method of clean up is: flush the soapy residue off the
pavement surface onto the surrounding soil after completion of works.
Over time, the debris accumulates and may eventually cause an
environmental problem requiring remediation. The cost of chemical removal
is usually double the cost of HPW and Track Jet due to the cost of the
chemicals.
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Runway Resurfacing and Repairing Using Modern Materials and Techniques Seminar Report 2012-2013
Benefits of this method are:
• Rubber is cleaned at the same rate as HPW.
• It softens and removes polymerized rubber.
• The work can be accomplished using airfield staff and equipment.
Disadvantages are:
• Once the process begins, the pavement/runway must remain closed until
clean up is complete.
• It is expensive in comparison to HPW and Track Jet.
• Poses an environmental problem due to chemicals not being
biodegradable over time.
• Time taken for process to be completed.
• Requires more than one personal to carry out process.
• Reacts with rubber seals in conventional sweepers and on runways.
• Large amount of effluent needed to be disposed of.
4.4 High Velocity Impact Removal or Shot Blasting
Propelling abrasive particles onto the runway surface that
blast the contaminant from the pavement surface using Shot-blasting. The
operation is environmentally clean since it is self .contained and the
equipment can be adjusted to produce the desired surface texture result. On a
non-grooved surface it collects the abrasive particles, loose contaminants and
dust from the runway surface. The steel is then recycled for re-use. The
primary reason using this method is for paint removal and the resurfacing and
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Runway Resurfacing and Repairing Using Modern Materials and Techniques Seminar Report 2012-2013
retexturing of pavement surfaces and not necessarily the removal of rubber
deposits .
Benefits are:
• It retextures pavement and removes rubber deposit in excess of 1,000
m² per hour.
• Retexturing is done by removing a thin layer of the pavement and
coincidentally removing rubber deposits as well.
• The equipment is truck-mounted and can easily be removed from the
runway (like HPW and TrackJet) in case of an emergency landing.
• The equipment cleans the surface while working.
Disadvantages are:
• Expensive to mobilise.
• Overall cost is expensive.
• Noise and vision hazards due to operation process of machine.
• Care is required to carry out machine operation.
• FOD hazard on airfields where steel shot becomes semi-embedded into
the surface and then dislodged later in time.
4.5Mechanical Removal (Grinding or Milling)
Mechanical Removal is generally carried out either by grinding
or milling. Like shot blasting, the primary reason for the machine is not the
removal of rubber from pavement surface.
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It is most effective in removing rough patches on highways and
profiling high spots on pavements. It also removes rubber deposits as its
process is carried out.
Benefits are:
• Removes high areas such as bumps on pavement surfaces or at joints
where slabs have shifted or faulted.
• Mills asphalt surface for preparation of overlaying.
• Improves pavement surface friction characteristics by removing a thin
surface layer.
Disadvantages:
• Can cause micro-cracking of the structure leading to accelerated aging
of the surface.
Damages surface texture.
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Runway Resurfacing and Repairing Using Modern Materials and Techniques Seminar Report 2012-2013
5. Stress Absorbing Membrane Interlayer(SAMI)
Asphalt interlayer system consist of a wide variety of products
and processes, each with unique benefits and specific placement methods to
ensure good adhesion to the underlying pavement. The products may be
classified in a number of categories such as; sand asphalts, grids, nonwovens,
steel reinforcements and SAMIs.
In general, a SAMI is placed on top of an existing pavement and
subsequently capped with a hot mix asphalt overlay (Fig.6).Its purpose is to
delay the propagation of cracking that originates in the pre-existing pavement
that will eventually reflect through to the new surface layers. Cracking in the
surface layers allows penetration of water, salt and other deleterious materials
that can accelerate the deterioration of the entire pavement structure once it
penetrates the aggregate base.
Fig: 6. SAMI within the pavement structure
“A saturated asphalt concrete is typically unaffected
structurally by water unless the asphalt aggregate is stripping prone. In
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Runway Resurfacing and Repairing Using Modern Materials and Techniques Seminar Report 2012-2013
contrast, a saturated base aggregate loses about 40% of its strength when
saturated.”( source: Pavement Preservation Task Group of Caltrans)
In effect each crack will allow a certain amount of water to
enter the road base hence negatively impacting the original engineered design.
An effective SAMI should therefore; provide additional tensile strength to the
pavement to combat reflective cracking, be flexible enough to allow it to
move within the pavement structure as well as providing a waterproof barrio
for the ingress water from the surface to the pre-existing pavement.
5.1 Stress Absorbing Membrane Interlayer (SAMI) using the FiberMat
process
FiberMatTM is a process that sandwiches strands of chopped fiberglass
between two layers of polymer modified asphalt emulsion, and is applied
using specialized equipment. The first layer of emulsion provides a bond to
the existing hard surface, with random interweaving of the fiberglass strands
providing tensile strength to the mix, the second application of asphalt
emulsion encapsulates the fiberglass, ensures the existing pavement is sealed,
and is quickly covered with a thin veil of aggregate. The aggregate is seated
into this second layer of emulsion using traditional rolling techniques and the
SAMI is capable of accepting traffic in approximately 20 minutes.
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Runway Resurfacing and Repairing Using Modern Materials and Techniques Seminar Report 2012-2013
This reinforced layer can be used as a temporary wearing surface, on
high volume roads, and is usually covered with a thin layer of hot mix asphalt
within 14 days. Once capped with hot mix, it becomes a true SAMI. Its
function is to seal the existing pavement with a resilient waterproof
membrane, reduce reflective cracking through the new wearing surface, and
ultimately prolong the useful service life of the road.
5.2 Constructing a SAMI using the FiberMat process
FiberMat is a flexible, waterproof membrane that incorporates
asphalt emulsion and fiberglass strands to combat reflective cracking, meeting
all three requirements of an effective SAMI. Patented equipment, developed
specifically for the FiberMat process, ensures even distribution of the
materials and precise computer controls to allow adjustments in application
rates while the machine is in motion.
This equipment is contained within a trailer that houses several spools
of fiber glass, the patented cutter assembly system, an asphalt emulsion pump
and distribution spray nozzles, plus the computer system that controls the
application rate of each component (figure7) . The unit is pulled by an asphalt
emulsion tanker, connecting the output lines of the tanker to the Fiber Mat
machine’s emulsion pumping system
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Runway Resurfacing and Repairing Using Modern Materials and Techniques Seminar Report 2012-2013
Fig:7. The fiberMat , Application System
The fiberglass strands are pneumatically blown between two separate layers of
asphalt emulsion (figure8) ensuring complete and even coverage of both
fiberglass and asphalt emulsion(figure9).
Fig:8. The fiberMat Application System Fig:9. Even distribution of materials
The even distribution of emulsion and fiberglass is achievable in a
swath up to 4m wide (easily covering an entire lane width).Computer
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Runway Resurfacing and Repairing Using Modern Materials and Techniques Seminar Report 2012-2013
synchronized nozzles and cutters allow the operator to vary the application
width to accommodate changes in pavement width, tapered sections and
turning lanes. It is possible to place FiberMat as narrow as 1m to a maximum
of 4m (150mm increments)
Fig:10. Application deck, showing separate lines of fiberglass capable of up to 4m width in single pass
To complete the process, it is necessary to imbed a layer of
aggregate in to the second layer of asphalt emulsion. Aggregate is placed with
a traditional chip spreader and seated using pneumatic rollers. The purpose of
the aggregate layer is to protect the newly constructed membrane from
vehicular traffic and construction equipment. The completed FiberMat
(SAMI) is capable of accepting traffic within 20 minutes, and should be
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Runway Resurfacing and Repairing Using Modern Materials and Techniques Seminar Report 2012-2013
overlaid with hot mix asphalt prior to the onset of freezing temperatures.The
unfinished road, FiberMat and aggregate are shown below(figure11).
Fig:11. Stages of FiberMat application
The entire ‘ train’ of equipment consists of the emulsion tanker,
FiberMat trailer, chip spreader, aggregate trucks and rubber tire rollers(Figure
12).
Fig:12.
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5.3 FiberMat Type B
APPLICATION
Specially developed patented machinery chops (60-90mm
length) fiberglass strands in- place and sandwiches them between two layers
of asphalt emulsion prior to the application of a light dressing of 6.35mm size
aggregate, which is then rolled into the surface. The glass fibres are applied at
a rate of 100-140g per m2, depending on the severity of the cracking, with
asphalt emulsion being applied in two simultaneous applications totaling 1.8-
2.3 litres/m2
FiberMat Type B uses the patented FiberDec process, a
combination of special polymer modified asphalt emulsion, chopped fiberglass
strands and aggregate. This mixture act as a highly resilient waterproof
membrane that seals and effectively delays reflective cracking.
This method is superior to other surface treatments as there
are no adhesion problems and the membrane can’t gather or tear because it is
sprayed in place.
FiberMat Type B is also faster to apply than another
conventional SAMI’s. It can be opened to traffic within initial lay-down and
the overlaying of the final wearing course; the latter may even be applied at
later date.
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Runway Resurfacing and Repairing Using Modern Materials and Techniques Seminar Report 2012-2013
FiberMat Type B has sufficient tensile strength and
flexibility to absorb movements in the pavement structure and can prevent the
pavement from cracking. Where pavement lateral movement of the overlay
might occur(due to cracks in the under laying material) FiberMat Type B
reduces the magnitude of the resulting strain in the overlay by spreading it
over a greater area. While conventional SAMI’s simply relieve stress,
FiberMat Type B acts like a cushion- its thickness absorbs stress, thereby
acting as a true stress absorbing membrane.
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Runway Resurfacing and Repairing Using Modern Materials and Techniques Seminar Report 2012-2013
6. URETEK’S UNIQUE TECHNOLOGIES (Floor lifting, Soil
consolidation, Void filling)
6.1 Method
After detailed analysis of the problem, we drill small holes to
the appropriate depth above or next to the problem area. Next we inject
specifically developed environmentally friendly material with uniquely strong
and expansive properties.
This material expands at a 100% predictable rate, filling
underground voids, consolidating the soil and stabilizing the surrounding area.
The process can also be used to lift sunken concrete or foundations with great
accuracy; to within a tolerance of 5mm per meter.
All this can be achieved without the need for excavation,
which is expensive and time-consuming.
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Runway Resurfacing and Repairing Using Modern Materials and Techniques Seminar Report 2012-2013
Fig:13.
6.2 ADVANTAGES
URETEK’s unique technologies are particularly effective and there are
a number of advantages that are not offered by alternative methods.
Universally accepted
These methods are universally accepted by architects, national and
international authorities and are even recommend by insurers
Phenomenal lifting capacity
These methods have a lifting capacity of 40,000 kg per square metre. We
can restore our concrete to full working strength no matter how heavy a load it
supports.
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Runway Resurfacing and Repairing Using Modern Materials and Techniques Seminar Report 2012-2013
Environmentally friendly
The resins used are without CFCs and can be applied in practically all
circumstances. They do not pollute and do not affect the quality of
underground water. They are even allowed for applications in the food
industry.
Minimal disruption
Fast installation, curing and cleanup equals minimal disruption, Also it
cause minimal dust and noise pollution. After only 15 minutes our material
has already reached 90% of its full strength, so load can immediately be
restored to a treated area.
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Runway Resurfacing and Repairing Using Modern Materials and Techniques Seminar Report 2012-2013
7. CONCLUSIONS
Runway rehabilitation scheme requires in-depth study of problems of
formulate repair scheme and to choose suitable materials and techniques for
repair. Use of new materials like modern asphalts, SAMI(FiberMat Type B) to
delay propagation of reflection cracks are found to be a lasting solution.
However, its long-term performance in context of Indian climatic conditions
is yet to be established and proven. However, no guidelines are available with
respect to various methods. These are the fields, which needs further studies.
In future, these materials are likely to find extensive usage in highway and
runway work.
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Runway Resurfacing and Repairing Using Modern Materials and Techniques Seminar Report 2012-2013
8.REFERENCES
Devendra Kumar., “Runway Maintenance Using modern Techniques”,
IRC Journal of Indian Highways, March 2005, pp.31-39
Pawan Kumar and A K Sriinivastave., “Glass Fibre Reinforced plastic”,
Civil Engineering Construction, November 2002,pp.45-50
ICAO Aerodrome Design Manual Part 3
Defence Estates Specification 013 – Marshall Asphalt for Airfields
Website:
www.trackjet.de.
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