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The Ministry of Infrastructure Development (before called Ministry of Public Works) is a Public Administration part of the Federal Government of the United Arab Emirates.
The Ministry of Infrastructure Development is in charge of
the Federal Roads in the Northern Emirates (Ras Al Khaima,
Fujairah, Ajman, Umm Al Quwain and Sharjah)
1,250 Km/carriageways (mainly on Highways)
These roads give service to a wide number of traffic. Great percentage of them are heavyweight vehicles, moving goods
through the whole country.
High values of heavyweight vehicles move daily along the Ministry’s road network with high axle loads
25 Counting stations and 5 WIM distributed along the
country provide the values for the ADT and axle weight
for heavyweight vehicles
Not only the loads but the heat, sand and other factors can have negative effects on the pavement’s behavior
Average values representing the worst condition for the road
IRI = 2.0 m/Km Cracking 15%
Rutting = 5mm Deflections = 65mm/100
GENERAL PREVIOUS CONDITION GENERAL CURRENT CONDITION
Sensitive areas presented damages in short time after construction. Observed damages related to the horizontal forces transmitted from the wheels (specially those from
heavyweight vehicles) appeared in the asphalt in short term
Resultant
Traffic light sections or near humps or roundabouts (high
deceleration forces)
Resultant U-turns and curved sections, where the traffic slows down
to change direction at slow speed
Some of the defects found in the sensitive areas were
related mainly with asphalt behavior due to the factors
before mentioned
The areas were the problems were located are:
(1) E-88 Dhaid – Masafi road
(Siji roundabout)
The areas were the problems were located are:
E-88 Dhaid – Masafi road (Siji
roundabout)
ADT: 7,000 vehicles/day HWV ADT: 1,900 vehicles/day Max Axle load: 22 ton
The areas were the problems were located are:
(2) E-88 Dhaid – Masafi road
(Manama roundabout)
The areas were the problems were located are:
(2) E-88 Dhaid – Masafi road
(Manama roundabout)
ADT: 7,000 vehicles/day HWV ADT: 1,900 vehicles/day Max Axle load: 22 ton
The areas were the problems were located are:
(3) E-18 Ras Al Khaima airport to Sha’ams road
(Traffic light)
The areas were the problems were located are:
(3) E-18 Ras Al Khaima airport to Sha’ams road
(Traffic light)
ADT: 14,500 vehicles/day HWV ADT: 4,000 vehicles/day Max Axle load: 21 ton
Those damaged areas needed to be repaired in order to keep
the safety and comfort of the users. The affected segments
showed high rates of rutting and also visible bleeding.
Due to all the factors affecting the roads all the undesired
effects affecting the asphalt could be avoided by improving the
physical characteristics of the asphaltic mixture used in the
courses
After studying different options it was decided to lay, in those
segments with evident defects, an asphaltic mixture modified
by any polymer able to improve the following mechanical
characteristics of the asphalt:
PROPERTIES
Flexibility
Internal cohesion
Thermal effects
Fatigue
Aging
The selected polymers type were a mixture of SBS (Styrene –
Butadiene –Styrene) and EVA (Ethylene – Vinyl – Acetate) in the
Bitumen, in order to improve the matrix covering the
aggregates in the admixture.
It was decided also to use bitumen already modified to be
stored and applied directly during the manufacturing process.
This combination will improve the flexural and compressive
stresses within the pavements
The production of the PMB was in charge of an specialist
company which had an asphalt plant was located in Sharjah, to
work for Sharjah Airport. After analyzing the properties of the
modified bitumen and the procedures for manufacturing,
Ministry of Infrastructure Development decided to go with that
specialist company for a test in those sections showing the
defects described before).
HOT MIX CHARACTERISTICS
Performance test (wheel tracking test)
HOT MIX CHARACTERISTICS
Performance test (wheel tracking test)
HOT MIX CHARACTERISTICS
Performance test (wheel tracking test)
The proposal consisted in milling 6cm of asphalt (wearing course) and apply the modified mixture manufactured with the PMB.
18 cm asphalt layers
ROAD BASE
ROAD SUB-BASE
PREVIOUS SECTION
12 cm previous asphalt layers
CURRENT SECTION
6 cm PMB layer
ROAD BASE
ROAD SUB-BASE
The asphaltic mixture was prepared in Sharjah plant and transported to the corresponding location, extending the mixture minimum at 120°C, and extending with conventional pavers
The extension of the asphalt was done in two stages, first in Ras Al Khaima (E-18) and after in both sections of Dhaid – Masafi road (E-88).
1st
2nd
Month of: September 2015
Month of: October 2015
RESULTS: Since the installation of the pavement in the roads, the monitoring of the layer condition continue until now. The general behavior is the expected one, obtaining excellent results without any sign of bleeding or sliding of the asphalt layers.
Expected extension of 3 years on the life span is expected on
the layers
Nanotechnology is defined by the size and includes a very wide field of application, including several science disciplines (organic chemistry, molecular biology, semi-conductors) and different applications as per example medicine, electronics or biomaterials.
MoID decided to do some test in laboratory as part of the
possibilities in new materials technology.
Sliding between two asphalt layers can be also a consequence
of high horizontal loads applied to the asphalt. This sliding can
be reduced if an increase in the adherence between layers is
produced
The Nanotechnology test are products Silane based. The last
form is Alkyl – Siloxane which creates a covalent link with the
emulsion and the asphalt increasing the bondage and closing
the physical spaces too, increasing therefore at the same time
the waterproof characteristics
Alkyl form is Cn – H2n+1 which is linked lately to the Siloxane
(that is an organosilicon with the form Si – O – Si)
Alkyl can be on the following forms:
And the links can be Methyl siloxane, Ethyl siloxane, Propyl
siloxane and Isopropyl siloxane
Test performed in Laboratory to be applied in tack coat: