1. Towards Standardizing Construction Specifications and Design Criteria of Agricultural Roads in the GCC Countries
Eng. Abdulaziz Al-Kulaib
Undersecretary,
Ministry of Public Works, Kuwait
Eng. Fadel Al-Ajmi
Assistant Undersecretary, Maintenance Division,
Dr. Sayed Metwali
Advisor, Maintenance Division,
Dr. Ahmad H. Aljassar
Associate Professor, Civil Engineering Department, Kuwait University
Fourth International Gulf Conference on Roads
10-13 November 2008, Doha, Qatar

2. Introduction ARs to serve farming areas.
Simplified design because of low traffic volumes.
One main concern: to minimize cost.
MPW has been constructing ARs for many years in North and South of Kuwait.

5. Introduction
In the past: light traffic consisting of light pickup trucks and occasional heavy trucks.
Therefore, did not require thick pavements.
Used to be 50 mm of wearing course on top of 150 mm of prepared subgrade.

6. Introduction
Rapid developments of farming areas in recent years resulted in heavier daily traffic (heavy trucks).
This led to rapid deterioration of pavements.
Need for stronger pavements was recognized.

7. Introduction
In recent years, MPW tendered 6 contracts for construction and maintenance of AR in the Northern and Southern farming areas (total value 12 million KD = 150 million QAR).
Cost of AR = 30,000 KD (390,000 QAR) per km.

8. Typical cross section of an AR
AASHTO recommends 3.6 m
Cross slope to facilitate drainage
Typical cross section of an AR

9. Cross section
Graded and compacted earth shoulders

10. Cross section
Sunken cast in-situ concrete curb to provide lateral support and protect pavement edge

11. Road profile Follows the natural flat terrain in farming areas.
Aesthetically pleasing, reduced construction costs, and improved safety.

12. Road profile

13. Drainage
Surface runoff is drained over the crowned pavement, then down the side slopes.
During winter season, vegetation grows along side slopes. This helps protect them against erosion.

14. Construction Subgrade soil is A-2-4 or better.
Dry density 1922 kg/m3 min.
CBR of 15 min.
Subgrade thickness is 30 cm min., compated in two layers (each not more than 15 cm).

15. Construction
Clearing & leveling

16. Construction
20 cm x 20 cm edge sunken curb

17. Construction
Subgrade

18. Construction
Subgrade

19. Construction
Subgrade

20. Construction 4 – 5 cm bituminous wearing course
8 – 10 cm bituminous base course

21. Construction 4 – 5 cm bituminous wearing course
8 – 10 cm bituminous base course

22. Material properties (aggregates)
Material Type
Size
Material Description
Main Properties
Fine Aggregate
Passing # 8 sieve
Natural Sand and crushed sand
Sand equivalent: 30 min. for crushed sand 45 min. for natural sand - soundness loss: 15% max. (AASHTO T-104)
Coarse Aggregate
Retained on # 8 sieve
Crushed natural stone and gravel
Cubic in shape.
Degree of crushing 80% min.
Has at least one fractured face.
Flakiness: 30% max. (BS 812).
Soft and friable particles: 3% max. for base course, 2% max. for binder and surface courses.
Sodium sulfate soundness loss: 12% max.
Abrasion loss: 40% max for surface course, 50% max for base and binder courses (AASHTO T-96).
Mineral Filler
100% passing #30
Min. 75% passing #200
Limestone, cement, or hydrated lime
Free Moisture 30% max.
Lime Index: 50% min.
Unhydrated lime: 9% max.
Carbon Dioxide: 8% max.

23. Material properties (bituminous mixes)
Sieve
% passing by weight
Acceptable
tolerances
Base course
Surface course
1 1/2"
100 -
± 5%
1"
3/4"
1/2"
46 – 76
66-95
3/8"
54 – 88
# 4
37 – 70
# 8
22 – 43
26 – 52
± 4 %
# 16
15 – 36
18 – 40
# 30
10 – 28
13 – 30
# 50
6 – 22
8 – 23
# 100
4 – 14
6 – 16
# 200
2 – 8
4 – 10
Bitumen (60/70) % by weight of total aggregate
3.5 – 5
4.5 – 6.5
± 0.4 %
Marshall Stability
1600 kg min.
1800 kg min.
Index of Retained Strength (AASHTO T-165), OR
Net Retained Strength
90% min.
14 kg/cm2 min.

24. Material properties Prime coat: - Medium-curing cut back (MC-70).
- Application rate 0.45 – 1.50 kg/m2.
- Application temperature 60o – 80o C.
- Not allowed if ambient temp. < 13o C.
- Not allowed in presence of surface free water.

25. Material properties Tack coat: - Slow-setting emulsion.
- Application rate 0.15 – 0.75 kg/m2.
- Application temperature 10o – 60o C.
- Not allowed if ambient temp. < 13o C.

26. Conclusion
ARs are becoming an important element of the highway system.
They provide farmers with all-weather access to markets.
Traditional thin pavement design is becoming insufficient to sustain heavier traffic loads on ARs.
Properties and design features may be of benefit for similar applications in the GCC.

27. وصلى الله وسلم وبارك على عبده ورسوله محمد . .
والحمد لله رب العالمين . .
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