DUBAI CENTRAL LABORATORY 1997
ORGANIZATION STRUCTRURE
Research & Standardization office 1997
Metrology Section 2002
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Consumer Products Section
Inspection & Certification Section
1998
1991
Engineering Material Laboratory Section
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1979
1975
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TABLE OF CONTENT INTRODUCTION TYPES OF ASPHALT PAVEMNT FAILURE IN DUBAI CURRENT AGGREGAT,BITUMEN SPECIFICATION SCOPE OF RESEARCH WORK MATERIALS CHARACTERIZATION DISCUSSION OF TEST RESULTS CONCLUSIONS
Source
Dubai highways serve a high concentration of heavily loaded trucks
Surface abrasion turning traffic
Rutting on some Dubai roadways
Alligator Cracking
Block Cracking
Sever Depression
The Marshall Method Of Mix Design Still In Use
Asphalt Evaluation Using Conventional Testing Still in Use
• This research program was to develop structural, high-stability mixes that will provide satisfactory service in the Dubai environment of high pavement temperatures and heavy truckloads.
Aggregate stockpiles for mixture blending at DCL
• • • • • •
Asphalt 1 (B1) EPPCO 60-70 Pen bitumen Asphalt 2 (B2) EPPCO 40-50 Pen bitumen Modified Asphalt 1 (M1) : - 4.5% SBS + 95.5% 60-70 pen asphalt Modified Asphalt 2 (M2) : - 5.5% EVA + 94.5% 60-70 pen asphalt
Maximum and minimum air temperature at Dubai International Airport 1994 to 2000 50 45 40
Air Temperature (ยบC)
35 30 25 20 15 10 5 0
1994
1995
1996
Maximum Air Temperature (C)
1997
1998
1999
Minimum Air Temperature (C)
2000
Predicted maximum and minimum pavement temperatures for Dubai using SHRP and LTPP pavement temperature models
Pavement Surface Temperature Frequency Distribution Dubai Airport Temperature Data 1994 to 2001 100% 90%
Percent of Observations Greater
80% 70% PG 64 189 days (6.2 months) of a year the pavement temperature exceeds the performance grade
60% 50%
PG 64 165 days (5.5 months) of a year the pavement temperature exceeds the performance grade
40% 30%
PG-72 Desired Grade 15 days (2 weeks) of a year the pavement temperature exceeds the performance grade of asphalt
20% PG 70 44 days (1.5 months) of a year the pavement temperature exceeds the performance grade of the asphalt cement
10% 0% 46
52
58 64 70 Maximum Pavement Surface Temperature (ยบC) SHRP Model
76 LTPP Model
82
BINDER AGING AND SUPERPAVE BINDER TEST SEQUENCE
Modifier Type
Generic Examples
Usual Effect on AC consistency during construction
Filler
•Mineral Filler (Crusher fines, lime, Portland cement, Fly ash) •Carbon Black
Harden
Extender
•Sulfur •Lignin
Harden
Rubber
•Natural rubber •Styrene – Butadiene or Styrene – Butadiene – rubber (SBR) •Polychloroprene Latex •Styrene-Butadiene-Styrene (SBS), Styrene-Isoprene-Styrene (SIS) •Crumb Rubber Modifier
P O L Y M E R S
Some materials may soften or harden AC depending upon the temperature range
Plastic
•Polyethylene / Polypropylene •Ethylene Acrylate copolymer •Ethyl-Vinyl-Acetate (EVA) •Polyvinyl Chloride (PVC) •Ehtylene Propylene or EPDM •Polyolefins
Combination
•Blends of polymers in rubber and plastic categories
Fiber
•Natural (Asbestos, Rock Wool) •Manmade (Polypropylene, polyester, fiberglass, Mineral, Cellulose
Harden
Oxidant
•Manganese Salts
Harden
Antioxidants
•Lead compounds •Carbon •Calcium salts
Soften
Hydrocarbon
•Recycling and rejuvenating oils •Hard and natural asphalts
Soften or Harden
Antistripping agents
•Amines •Lime
Soften
Harden
Effect is same as rubber
BINDER AGING AND SUPERPAVE BINDER TEST SEQUENCE Test / Equipment
Purpose
Performance Parameter
Unaged / original RTFO Aged
Binder Conditions
PAV Aged
Flash Point
Measure temperature at which vapors may ignite
Safety
RV
Measure binder properties at high construction temp.
Resistance to permanent deformation (rutting) and fatigue cracking
RTFO
Simulate binder hardening (aging) during HMA production & construction
Resistance to aging, durability, during construction.
DSR
Measure binder properties at high and intermediate service temperatures
Resistance to permanent deformation (rutting) and fatigue cracking
PAV
Simulate binder hardening (aging) during HMA service life
Resistance to aging, durability, during service life.
DSR
Measure binder properties at high and intermediate service temperatures
Resistance to permanent deformation (rutting) and fatigue cracking
BBR
Measure binder properties at low service temperatures
Resistance to thermal cracking
DTT
Measure binder properties at low service temperatures
Resistance to thermal cracking.
Stiffness Characteristics of conventional and ideal modified binder
Brookfield viscometer
Dynamic Shear Rheometer
Rolling thin film oven test on asphalt binder.
Pressure aging vessel test on asphalt binder at DCL
Binder Test Results Test Name
Test Method
60/70 Bitumen 61 49.8 462
40/50 Bitumen 45 52.2 569
60/70+4.5 % SBS 49 62.8 1367
60/70+5.5% EVA 42 72.6 616
135OC
313
550
1238
529
160OC
75
200
425
188
175OC
38
138
225
88
64OC
1.86
2.54
--
--
70OC
0.89
1.21
2.601
2.496
76OC
0.43
0.53
1.441
1.042
82OC
--
--
0.89
--
58OC
8.34
--
--
--
64OC
3.66
4.94
--
--
70OC
1.69
2.07
4.885
5.233
76OC
--
--
2.539
2.3
82OC
--
--
1.5
--
19OC
3.49
--
--
--
22OC
2.13
5.43
--
--
25OC
1.7
4.54
5.27
5.9
28OC
--
--
3.62
4.03
31OC
--
--
2.57
1.86
Performance Grading
PG-64
PG-64
PG-76
PG-76
Penetration (0.01 mm) Softening Point (degree C) Kinematic Viscosity @ 135oC (cSt)
ASTM D5 ASTM D36 ASTM D 2170
Brookfield Rotaional Viscosity (cp) :
ASTM D 4402
DSR-Original Binder (G*sinδ (Kpa)):
AASHTO TP5
DSR-RTFO Residue (G*/sinδ (Kpa)):
DSR-PAV Aged (G*sinδ (Mpa))
AASHTO TP5
:
AASHTO TP5
RTFO – Rolling Thin Film Oven PAV
–
DSR – Dynamic Shear Rheometer Pressure
Aging
Vessel
Aggregate test results Test result Test Name
Test Method
Fujairah Wadi Aggregate
Dhaid Mountain
31mm
19mm
9.5mm
5mm
37.5mm
20mm
10mm
5mm
DM 301:1998
100
100
100
--
100
100
100
--
% of aggregate with full crushed faces
DM 300:1998
95
91
91
--
88
88
90
--
% Finer than 0.075 mm
ASTM C 117
0.0
1.9
1.9
17.0
0.2
0.1
0.2
12.3
Soundness (MgSO4) (%)
ASTM C-88
0.4
0.3
0.6
0.7
0.2
1.5
2.4
3.4
Elongation Index
BS 812
23
31
11
21
29
26
Flakiness Index
BS 812
5
7
31
9
16
Aggregate Crushing Value (%)
BS 812
11
11
11
--
15
LA Abrasion Value (%)
ASTM C-131
9.8
9.7
12.4
--
Specific GravityBulk Specific GravitySSD
ASTM C-127
2.929
2.921
2.911
ASTM C-127
2.938
2.932
Specific GravityApparent
ASTM C-127
2.954
2.953
% of Clay Lumps
ASTM C-142
Sand Equivalent
ASTM D2419
% Aggregate with one crushed face (min.)
--
--
--
23
--
10
10
--
10
13
16
--
2.871
2.98
2.95
2.92
2.92
2.922
2.895
2.98
2.96
2.95
2.94
2.942
2.942
3.00
2.99
2.99
2.98
0.13
0.22
0.37
0.3
74
80
The Marshall Hammer was used to compact some mixes
Gyratory Compactor
Ignition Oven
Number of gyrations required for various traffic levels (from SHRP). Traffic Level, Millions of ESALs
Design Number of Gyrations
Less than 1
50
1 - 10
75
10 - 30
100
Greater than 30
125
Core thicknesses and specific gravities Abu Dhabi Road
Al Qusais Road
Core No.
Thicknes s mm
Specific Gravity
Core No.
Thicknes s mm
1
60
2.600
1
2
63
2.601
3
59
4
Nadd Al Shiba Road Core No.
Thicknes s mm
Specific Gravity
49
Specifi c Gravity 2.552
1
49
2.407
2
46
2.543
2
47
2.376
2.605
3
50
2.533
3
47
2.424
63
2.583
4
49
2.526
4
47
2.403
5
62
2.602
5
47
2.556
5
48
2.440
6
64
2.591
6
46
2.522
6
48
2.408
7
65
2.615
7
46
2.563
7
49
2.445
8
67
2.599
8
47
2.528
8
47
2.419
9
64
2.593
9
49
2.561
9
48
2.419
10
61
2.607
10
47
2.525
10
48
2.440
Avg.
62.8
2.600
Avg.
47.6
2.541
Avg.
47.8
2.418
Binder contents and voids in mix Binder Content (average of 4 samples)
Maximum Specific Gravity (Gmm)
Voids Total Mix %
Abu Dhabi Road
3.80
2.732
4.83
Al Qusais Road
4.05
2.677
5.08
Nadd Al Shiba Road
4.20
2.576
6.13
Test Site
Number of gyrations required for Dubai roads.
Road Site
Traffic Level
Field Density
Gyrations to Yield Field Density
Abu Dhabi Road
High
2. 600
153
Al Qusais Road
Medium
2.541
134
Nadd Al Shiba Road
Low
2.418
57
Aggregate gradations for initial 30 mix designs Mix Type Sieve Size mm
Corps Large
SHRP Large
Dubai DBM
Dubai AC
Corps Dense
SMA-B
SMA-A
SHRP Dense
37.5
100.0
100.0
100.0
100.0
100.0
100.0
100.0
100.0
25
89.0
95.0
99.6
100.0
100.0
100.0
100.0
100.0
19
79.0
86.0
96.3
99.0
100.0
96.0
100.0
100.0
12.5
70.0
72.0
78.0
76.0
89.0
60.0
99.0
95.0
9.5
63.0
62.0
67.0
67.0
82.0
49.0
65.0
83.0
4.75
51.0
44.0
43.5
56.0
60.0
28.0
28.0
58.0
2.36
42.0
30.0
29.6
38.0
53.0
19.0
20.0
35.0
1.18
34.0
26.0
21.0
25.0
41.0
16.0
17.0
24.0
0.6
26.0
18.0
14.0
16.0
31.0
14.0
15.0
16.0
0.3
19.0
13.0
9.0
12.0
21.0
13.0
14.0
12.0
0.15
13.0
10.0
6.0
6.3
12.0
11.0
12.0
8.0
0.075
4.5
4.0
2.7
3.4
4.5
9.0
9.0
4.0
NMPS
37.5
37.5
19
19
19
19
12.5
12.5
Aggregate Gradations for Additional Mixes Sieve Size (mm)
Dubai AC Base
Maintenance Mix
25 mm Wearing Course
19 mm Wearing Course
37.5
100
--
100
25
95
--
96
100
19
78
100
82
99
12.5
65
98
63
76
9.5
58
85
55
64
4.75
48
60
35
43
2.36
34
36
24
24
1.18
24
27
16
19
0.600
16
17
11
13
0.300
10
11
7
9
0.150
6
8
4.8
7
0.075
3.0
3.9
3.1
3.6
Mixing and compacting temperature for different binder used Bitumen
Mixing Temperature (oC)
Compacting Temperature (oC)
B1
150±2
138±2
B2
160±2
150±2
M1
180±2
168±2
M2
163±2
150±2
Aggregate blends for mixes were carefully weighed from aggregate fractions
Aggregate blends and binder were hand-mixed and held to prescribed temperature for compaction
Mix Design Results
Mix Number
Mix ID
1 2
Maximum Specific Gravity (Gmm)
Design AC
Compaction Effort
Air Voids
VMA -0.5%
Opt
+0.5%
1DD11
3.7
75-Marshall
7.3
15.7
2.766
2.742
2.718
1DA11
3.8
75 Marshall
7.0
16.0
2.758
2.734
2.711
3
1SD11
4.7
153 SGC
4.0
15.6
2.712
2.689
2.666
4
1CD11
4.8
75 Marshall
4.5
16.0
2.711
2.688
2.665
5
1CL11
4.3
75 Marshall
4.2
14.0
2.736
2.713
2.690
6
1SL11
3.8
153 SGC
3.9
12.8
2.762
2.739
2.715
7
2DD1M1
3.7
75 Marshall
7.2
15.6
2.761
2.737
2.714
8
2DA1M1
4.0
75 Marshall
7.0
16.6
2.752
2.728
2.705
9
2SD1M1
5.0
153 SGC
4.2
16.3
2.698
2.675
2.653
10
2CD1M1
4.8
75 Marshall
4.2
16.0
2.709
2.686
2.664
11
2SMA1M1
6.3
50 Marshall
4.1
19.0
2.632
2.610
2.589
12
2SMB1M1
5.5
50 Marshall
4.2
16.7
2.678
2.656
2.634
13
2SL1M1
3.6
153 SGC
3.9
12.1
2.761
2.738
2.714
14
3DA12
3.8
75 Marshall
6.7
15.8
2.758
2.734
2.711
15
3SD12
4.8
153 SGC
4.0
15.5
2.711
2.688
2.666
16
4DA21
4.0
75 Marshall
7.0
16.2
2.790
2.754
2.731
17
4SD21
5.0
153 SGC
4.0
16.0
2.736
2.712
2.689
18
5DA22
4.0
75 Marshall
7.4
16.3
2.780
2.756
2.732
19
5SD22
5.0
153 SGC
4.3
16.2
2.737
2.714
2.691
20
6DA2M1
4.2
75 Marshall
7.1
16.7
2.773
2.749
2.726
21
6SD2M1
5.0
153 SGC
4.1
16.0
2.737
2.713
2.690
22
7DD1M2
3.7
75 Marshall
7.5
15.9
2.765
2.741
2.718
23
7DA1M2
4.0
75 Marshall
6.6
16.0
2.756
2.732
2.709
24
7SD1M2
4.8
153 SGC
4.6
16.2
2.706
2.683
2.661
25
7CD1M2
5.0
75 Marshall
4.5
16.6
2.699
2.676
2.654
26
7SMA1M2
6.2
50 Marshall
4.2
18.4
2.642
2.621
2.599
27
7SMB1M2
5.7
50 Marshall
4.0
17.0
2.671
2.649
2.627
28
7SL1M2
3.6
153 SGC
3.9
12.3
2.767
2.743
2.720
29
8DA2M2
4.2
75 Marshall
7.2
16.9
2.773
2.749
2.726
30
8SD2M2
5.0
153 SGC
5.0
16.1
2.733
2.710
2.687
Mix design criteria for additional mixes New Wearing Course Mixes Mix Property/Specification
Current AC Base
12.5 mm
19 mm
19 mm
25 mm
25 mm
Mix ID
9-Base-2-1
9-Maint-2-2
9-19L-2-2
9-19H-2-2
9-25L-2-2
9-25H-2-2
Mix Design Compaction (Gyrations in SHRP Gyratory)
75 blows Marshall hammer (75-blow equivalent)
153
153
153
153
153
9800 N
--
--
--
--
--
Marshall Flow, 0.25 mm
8 - 16
--
--
--
--
--
Stiffness, min.
1225
--
--
--
--
--
Voids in Mineral Aggregate
12-15
14
13
14
12
14
4-8
4–5
4-5
5-8
4-5
5-8
50 - 65
65 – 75
65 - 75
50 - 65
65 - 75
50 - 65
25
--
--
--
--
--
Dust/Binder Ratio
0.6 - 1.5
0.6 – 1.2
0.6 – 1.2
0.6 – 1.5
0.6 – 1.2
0.6 – 1.5
% G mm @ N ini (10)
--
Less than 89%
Less than 89%
Less than 89%
Less than 89%
Less than 89%
% G mm @ N max (253)
--
Less than 98%
Less than 98%
Less than 98%
Less than 98%
Less than 98%
Gyrations to give 75-blow Marshall equivalent
153
153
153
153
153
Marshall Stability, min.
Voids Total Mix
Voids Filled with Asphalt Marshall Stability Loss, %
Manufacture of Test Specimens (Number of Gyrations in SHRP Gyratory)
Test Method and Performance Measures Test Method
Rutting
Stiffness
Asphalt Pavement Analyzer
Repeated Shear Constant Height
Frequency Sweep Constant Height
Repeated Load Accumulated Strain
Resilient Modulus
Flexural Beam Fatigue
Gyratory Test Machine
Indirect Tensile Strength
Cracking Resistance
Compaction Characteristics
Agencies Conducting Performance Tests •Dubai Central Laboratory
-Asphalt Pavement Analyzer -Indirect Tensile Strength •National Center for Asphalt Technology
-SHRP Shear Tester -Corps of Engineers Gyratory Test •University of Illinois, Urbana –Champaign
-Confined Creep (repeated load) -Resilient Modulus -Fatigue
Asphalt pavement analyzer
Close-up of loading wheels over test specimens.
Indirect tensile strength test
APA rut depths for asphalt mixtures at optimum asphalt content
Indirect tensile strength data plot
Rut depth mm.
Rutting depth at optimum binder content
8 7 6 5 4 3 2 1 0 Mix 1
Mix 2
Mix 3
Mix 4
Mix 5
Mix 6
Mix 7
Mix 8
Mix No. rut depth at 50 degree C
rut depth at 70 degree C
Mix 9
Mix 10
Indirect tensile strength at optimum binder content
Indire ct Tensile S tre ngth kP a
2000 1600 1200 800 400 0 Mix 1
Mix 2
Mix 3
Mix 4
Mix 5
Mix 6
Mix 7
Mix 8
Mix No. IDT at25 degree C
IDT at35 degree C
Mix 9 Mix 10
60 – 70 Versus 40 – 50 Penetration Asphalt Cement. Performance Comparison
Number of Test Result Favoring Rutting Tests
Stiffness Tests
Compliance Cracking Tests
Compaction Tests
40 – 50
37
50
9
22
60 – 70
27
18
7
14
Best Material
40 – 50
40 – 50
Similar
40 - 50
From the analysis of the asphalt materials test data the following results are shown: The 40 – 50 pen asphalt shows improved rutting performance. The 40 – 50 pen asphalt shows improved stiffness. The 40 – 50 and 60 – 70 pen asphalts show similar performance in cracking resistance tests. The 40 – 50 pen asphalt shows improved compaction performance.
60 – 70 pen Versus SBS Modified Asphalt Cement Performance Comparison
Number of Test Result Favoring Rutting Tests
Stiffness Tests
Compliance Cracking Tests
Compaction Tests
SBS
84
98
21
47
60 – 70
28
21
7
16
Best Material
SBS
SBS
SBS
SBS
From the analysis of the asphalt materials test data the following results are shown: The SBS modified asphalt shows improved rutting performance. The SBS modified asphalt shows improved stiffness. The SBS modified asphalts show improved performance in cracking resistance tests. The SBS modified asphalt shows improved compaction performance.
60 – 70 pen Versus EVA Modified Asphalt Cement Performance Comparison
Number of Test Result Favoring Rutting Tests
Stiffness Tests
Compliance Cracking Tests
Compaction Tests
EVA
55
67
11
24
60 – 70
25
18
9
21
Best Material
EVA
EVA
Similar
Similar
From the analysis of the asphalt materials test data the following results are shown: The EVA modified asphalt shows improved rutting performance. The EVA modified asphalt shows improved stiffness. The EVA modified asphalts show similar performance to 60 – 70 cracking resistance tests. The EVA modified asphalt shows similar performance to 60 – 70 compaction performance.
40 – 50 pen Versus SBS Modified Asphalt Cement Performance Comparison
Number of Test Result Favoring Rutting Tests
Stiffness Tests
Compliance Cracking Tests
Compaction Tests
SBS
42
39
10
23
40 – 50
22
29
6
13
Best Material
SBS
SBS
SBS
SBS
From the analysis of the asphalt materials test data the following results are shown: The SBS modified asphalt shows improved rutting performance. The SBS modified asphalt shows improved stiffness. The SBS modified asphalts show similar performance in cracking resistance tests. The SBS modified asphalt shows improved compaction performance.
40 – 50 pen Versus EVA Modified Asphalt Cement Performance Comparison
Number of Test Result Favoring Rutting Tests
Stiffness Tests
Compliance Cracking Tests
Compaction Tests
EVA
43
47
9
10
40 – 50
21
21
7
26
Best Material
EVA
EVA
Similar
40 - 50
From the analysis of the asphalt materials test data the following results are shown: The EVA modified asphalt shows improved rutting performance. The EVA modified asphalt shows improved stiffness. The EVA modified asphalts show similar performance to 40 – 50 cracking resistance tests. The 40 – 50 pen asphalt shows improved compaction performance.
SBS Versus EVA Modified Asphalt Cement Performance Comparison
Number of Test Result Favoring Rutting Tests
Stiffness Tests
Compliance Cracking Tests
Compaction Tests
EVA
64
89
13
24
SBS
80
64
23
57
Best Material
SBS
EVA
SBS
SBS
From the analysis of the asphalt materials test data the following results are shown: The SBS modified asphalt shows improved rutting performance. The EVA modified asphalt shows improved stiffness. The SBS modified asphalts show improved performance in cracking resistance tests. The SBS modified asphalt shows improved compaction performance.
CONCLUSIONS • The use of penetration grade bitumen to be ceased, and performance graded bitumen shall be introduced.
CONCLUSIONS • The 40/50 penetration asphalt has improved performance for surface mixture where stiffness, and resistance to deformation are predominant desired properties. Therefore 40/50 penetration asphalt is recommended for the majority of surface mixture.
CONCLUSIONS • In slow and stopped traffic with heavy vehicle loads, a PG 76 is recommended to prevent rutting and shoving.
• The polymer modified asphalt cement showed improved rutting resistance as compared to the non-modified asphalt binders. • The SBS modifier gave slightly improved performance based test results as compared to EVA modifiers.
CONCLUSIONS • Contract Specification shall be amended to include all new advanced tests • DCL can carry out binder and asphalt mixture testing using these advanced equipments • DCL can give training sessions for external clients using new advanced testing on binder and asphalt mixtures
DUBAI MUNICIPALITY
DUBAI CENTRAL LABORATORY DEPARTMENT
Coarse Aggregates For Bituminous Paving Mixtures
Fine Aggregates For Bituminous Paving Mixtures
Aggregate Grading for Asphaltic Concrete
Aggregate Grading for DBM Base Course
Aggregate Grading for DBM Wearing Course
Properties of Mix For AC
Properties of Mix For DBM
Bitumen Properties
CONCLUSIONS & RECOMMENDATIONS Based on the research conducted under Stage 3B, the following conclusions and recommendations appear warranted. ASPHLAT BINDER
The 40 – 50 pen asphalt has improved performance for surface mixtures where stiffness and resistance to deformation are predominant desired properties. Therefore 40 – 50 pen asphalt is recommended for the majority of the surface mixtures. An analysis of the frequency distribution of pavement temperatures in Dubai yields a conclusion that the recommended binder for Dubai highways should be PG 72. The pavement temperature only exceeds the PG 72 performance grade for 4percent of the year. This desired grade of PG 72 could be a neat (unmodified) asphalt since the 40 – 50 pen asphalt almost grades as a PG 70. In slow and stopped traffic with heavy vehicle loads, a PG 76 is recommended to prevent rutting and shoving. The PG 76 will likely to be obtained by modification of existing asphalts.
An analysis of the pavement temperature at a 50 mm depth shows that the temperatures are considerably lower. This analysis indicates that a PG 64f is adequate for all layers 50 mm or greater below the pavement surface. Use of softer PG binders below the 50 mm level will provide adequate resistance to rutting and will increase the resistance to cracking.
CONCLUSIONS & RECOMMENDATIONS Based on the research conducted under Stage 3B, the following conclusions and recommendations appear warranted.
ASPHLAT MODIFIERS
The polymer modified asphalt cements showed improved rutting resistance and fatigue performance as compared to the non-modified asphalt binders. The frequency test data from the SHRP Shear Test show improved stiffness at low frequencies (representing slow vehicles) with the modified binders. The SBS modifier gave slightly improved performance-based test results on most mixes as compared to the EVA modified.
The research is being conducted in the following stages: • Stage 3A – Review Of Stages 1 and 2, Development Test Plan. • Stage 3B – Laboratory Mix Design. • Stage 3C – Preliminary Pavement Design Manual. •Stage 3D – Field Trials and Report.
•Stage 4 – Mix Design and Pavement. Manual. Training – Five Training Sessions
Research Work • Research program was made to develop, high-stability mixes using available bitumen & modified binder, that will provide satisfactory service in the Dubai environment of high pavement temperatures and heavy truckloads.
Aggregate Test Results Test result Test Name
Test Method
Fujairah Wadi Aggregate
Dhaid Mountain
31mm
19mm
9.5mm
5mm
37.5mm
20mm
10mm
5mm
DM 301:1998
100
100
100
--
100
100
100
--
% of aggregate with full crushed faces
DM 300:1998
95
91
91
--
88
88
90
--
% Finer than 0.075 mm
ASTM C 117
0.0
1.9
1.9
17.0
0.2
0.1
0.2
12.3
Soundness (MgSO4) (%)
ASTM C-88
0.4
0.3
0.6
0.7
0.2
1.5
2.4
3.4
Elongation Index
BS 812
23
31
11
21
29
26
Flakiness Index
BS 812
5
7
31
9
16
Aggregate Crushing Value (%)
BS 812
11
11
11
--
15
LA Abrasion Value (%)
ASTM C-131
9.8
9.7
12.4
--
Specific GravityBulk Specific GravitySSD
ASTM C-127
2.929
2.921
2.911
ASTM C-127
2.938
2.932
Specific GravityApparent
ASTM C-127
2.954
2.953
% of Clay Lumps
ASTM C-142
Sand Equivalent
ASTM D2419
% Aggregate with one crushed face (min.)
--
--
--
23
--
10
10
--
10
13
16
--
2.871
2.98
2.95
2.92
2.92
2.922
2.895
2.98
2.96
2.95
2.94
2.942
2.942
3.00
2.99
2.99
2.98
0.13
0.22
0.37
0.3
74
80