runway resurfacing and repair by using modern materials and techniques

1. Runway Resurfacing and Repair by Using
Modern Techniques and Materials
Guided By Presentation By
Poorna Prajna S Faiz Ahmed Shaikh Budan

2. Contents
I. Introduction
II. Modern Asphalts
III. Uses of Asphalt in Airfield
IV. Rubber Removal Techniques
a) High Water Pressure (HWP)
b) TrackJet (Ultra High-Pressure Water blasting)
c) Chemicals
d) High Velocity Impact Removal or Shot Blasting
e) Mechanical Removal (Grinding or Milling)
V. Stress Absorbing Membrane Interlayer (SAMI)
a) Stress Absorbing Membrane Interlayer (SAMI) using the FiberMat process
b) Construction of a SAMI using the FiberMat process
VI. URETEK’S Unique Technologies (Floor lifting, Soil consolidation, Void filling)

3. I. Introduction
 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 .
 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.

4. II. Modern Asphalts
o 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 as well as binders for thin surfacing and
foam mixes.
o One fuel damage resisting product Nyguard, was
used at Bristol Airport to bring two redundant
runways back into use as taxiways and for aircraft
refuelling and parking. These ancillary areas are seen
as lower risk.

5. o In a recent contract at Liverpool Airport, tarmac reused runway plannings for sections of recycled pavement.
These areas the outer strips of the runway were reconstructed 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
o 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.
o 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.
o 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.

6. III. Uses of Asphalt in Airfield
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.
The following areas on a typical airfield are likely to require hard paving: -
o runways
o taxi-ways providing access to runways
o aircraft parking, re-fueling or servicing aprons
o hanger floors
o car, bus or commercial vehicle parking areas
o access roads
o edge drainage (French Drains) for runways and
taxiways

7. IV. Rubber Removal Techniques
The most common methods of pavement retexturing are:
a) High Water Pressure,
b) Ultra High Water Pressure (Track Jet),
c) Chemical,
d) Shot Blasting,
e) Mechanical Process.

8. a) High Water Pressure (HWP)
o Rubber is removed by means of rotary devices that move along the surface as it
cleans.
o This is done utilizing up to 30 gallons of water per minute at pressures of
between 100 to 1,000 bar.
o The water that penetrates the surface effectively cleaning rubber deposits creates
an hydraulic effect.
o This helps to increase the frictional values and surface texture of the pavement.
o A combined suction part or a sweeper that picks up the rubber debris during its
operations usually accompanies it.
o This allows for the pavement to be easily and quickly.

9. Advantages
a) The speed at which rubber is removed (1,200 m² per hour are claimed).
b) The cost efficiency of the process (water is generally provided).
c) The improved friction characteristics of the pavement due to penetration
of the water and the removal of rubber.
d) Its usage is independent of weather and can be operated in cold, damp
wintry conditions.
e) The ease of getting off the runway in the event of an emergency.

10. Disadvantages
a) Noise from the operation requires the wearing of hearing protection.
b) Eye protection should also be worn in the vicinity of the machine while
in operation.
c) Appropriate disposal of waste material is required.
d) Does loosen surface matrix encouraging the loss of fine materials.
e) Cleaning rate is 70% with one run.
f) Damages sealing.
g) Cannot be used to clean AGL.

11. b) TrackJet (Ultra High-Pressure Water blasting)
o The TrackJet, an Ultra High-Pressure Water blasting machine developed by Bernd
Weigel in Germany, is widely used at BAA airports as well as European highways
for retexturing and paint marker removal.
o This machine has consistently removed 100% of rubber build-up and pavement
markings from pavements without touching the pavement micro or macro texture.
o It utilizes a nozzle system that is truck mounted, applying very little water at very
high pressure through a unique computer-controlled system.

12. Advantages
a) Optimum treatment with care of pavement surface.
b) Applicable to all kinds of surfaces; for example asphalt, anti-skid, petro-grip and
concrete.
c) Best possible friction values.
d) High environmental compatibility.
e) No damage to grooving, runway lighting systems, marker paints and joint
sealing.
f) High environmental care due to extremely low water and fuel consumption.

13. Disadvantages
a) Appropriate disposal of waste material is required.
b) Some airport staff claims that up to 800 m² per hour
cleaning (but 100% rubber removed) is too
little.
TrackJet (Ultra High-Pressure Water blasting

14. c) Chemicals
o 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.
o 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.
o The debris cannot be swept up using conventional sweepers since the chemicals will react
with the rubber seals within the sweeper

15. Advantages
a) Rubber is cleaned at the same rate as HPW.
b) It softens and removes polymerized rubber.
c) The work can be accomplished using airfield staff and equipment.

16. Disadvantages
a) Once the process begins, the pavement/runway must remain closed until clean up is
complete.
b) It is expensive in comparison to HPW and Track Jet.
c) Poses an environmental problem due to chemicals not being biodegradable over time.
d) Time taken for process to be completed.
e) Requires more than one personal to carry out process.
f) Large amount of effluent needed to be disposed of.

17. d) 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
retexturing of pavement surfaces and not necessarily the removal of rubber
deposits.

18. Advantages
 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.

19. Disadvantages
a) Expensive to mobilise.
b) Overall cost is expensive.
c) Noise and vision hazards due to operation process of machine.
d) Care is required to carry out machine operation.
e) FOD hazard on airfields where steel shot becomes semi-embedded into the
surface and then dislodged later in time.

20. e) Mechanical 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.
 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.

21. Advantages
a) Removes high areas such as bumps on pavement surfaces or at
joints where slabs have shifted or faulted.
b) Mills asphalt surface for preparation of overlaying.
c) Improves pavement surface friction characteristics by removing a
thin surface layer.

22. Disadvantages
a) Can cause micro-cracking of the structure leading to
accelerated aging of the surface.
b) Damages surface texture.

23. V. Stress Absorbing Membrane Interlayer (SAMI)
Stress Absorbing Membrane Interlayers) are placed between pre-
existing pavements and hot mix asphalt layer overlays to seal existing
cracks and retard reflective cracking.

24. a) Stress Absorbing Membrane Interlayer (SAMI) using
the FiberMat process
 FiberMat TM is a process that sandwiches strand 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
inter-weaving 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.

25. b) 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.

26. Construction of a SAMI using the FiberMat process
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. 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.

27.  The fiberglass strands are pneumatically blown between two separate layers of asphalt emulsion
(figure1) ensuring complete and even coverage of both fiberglass and asphalt emulsion(figure2).

28.  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 overlaid
with hot mix asphalt prior to the onset of freezing temperatures. The unfinished road,
FiberMat and aggregate are shown below.

29.  The entire ‘train’ of equipment consists of the emulsion tanker, FiberMat trailer, chip
spreader, aggregate trucks and rubber tire rollers.

30. VI. URETEK’S Unique Technologies (Floor lifting, Soil consolidation,
Void filling)
o 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.
o 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.
o All this can be achieved without the need for excavation,
which is expensive and time-consuming.

31. Advantages
o Universally accepted
These methods are universally accepted by architects, national and international authorities and are
even recommend by insurers
o 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.
o Environmentally friendly
o Minimal disruption
Fast installation, curing and clean up 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.
o Light weight
These materials are extremely light weight, weighing 10% less than comparable to asphalt materials

32. Thank you