1. Special Micro-surfacing applications
W13 session
APWA 2013 Annual meeting,
Jacksonville, FL

2. Contents
Definition of Microsurfacing technology;
Formulations
Fields of application;
Gap Graded formulations
Utilization of Synthetics fibers
Crack relief system with using Microsurfacing:
Heavy duty Crack relief system using Microsurfacing
Colored microsurfacing
Futurs developments

3. Definition of Microsurfacing technology

4. Definitions of Microsurfacing technologies
The microsurfacing material is special cold mixture applied at
ultra-thin thickness of 7 à 15 mm (1/4 to ½”), as surface layer,
to intend of friction adherence and to seal the existing surface.
A maintenance Technique
Preventive :
To prevent some future superficial degradations of the
surface pavement.
Corrective :
To correct superficial degradations of a surface
pavement

5. Microsurfacing
Definitions of the constituents
1. Aggregates
2. Mineral Filler
3. Bitumen Emulsion
4. Water
5. Fibers
(depending of the application)

6. Microsurfacing
Criteria of selection – Speed of the intervention
Aggregates Filler
Water
additives
Emulsion
Mix
Spreader
box
Direction
Mixing time
15 to 45 sec
Brown Mix and
homogeneous
Black mat
Setting time
2 to 10 minutes
Opening to traffic between 30 - 60 minutes
.Setting time 10 minutes
.Time for traffic opening < 60 minutes

7. Microsurfacing
Definitions - Production
Mobil unit machine
o Transportation of the constituents
o Storage of the constituents
o Dosage of the constituents
o Mixing of the constituents
Application by a spreader box with variable width
Continuous Unit
Traditional Unit Semitrailer Unit

8. Congrès Bitume Québec- 31 mars
2011 - page 8
Mobil Unit
•Storage
•Dosage
Spreader box
•Mixing and - laying
Microsurfacing
Speed of application :
8000 to 25 000 sy² per day
Microsurfacing
Definitions - Production

9. Microsurfacing
Formulation study
Mixing and setting time tests
• Allow to determine the compatibilty between the components
• Determination of the mixing time and setting time.

10. Cohesion test
• Benedict cohesion tester: application of a torque on a sample through a rubber
disk with a charge of 200 kPa.
• Cohesion mesured on Microsurfacing samples at differents curing time (30, 60
and 90 minutes)
Microsurfacing
Formulation study

11. Testing after curing
Wet Track abrasion test (WTAT)
o Determination of the abrasion resistance of the mixture (in fonction of
the bitumen content)
o Simulation of abrasion from the vehicules tires (curves)
o Determination of the minimum bitumen contant
Load wheel tester (LWT) – Bleeding susceptibility
o Determination of the maximum bitumen content where risks of bleeding
appears
Microsurfacing
Formulation study

12. Wet track abrasion test (WTAT)
Microsurfacing
Formulation study

13. Wet track abrasion test (WTAT)
Microsurfacing
Formulation study

14. Load wheel tester (LWT)
Microsurfacing
Formulation study

15. Specifics performances tests
o Lateral displacement whit LWT for rutting correction application
Microsurfacing
Formulation study

16. Specifics performance tests
o Schulze-Breuer compatibility
Grade Point Abrasion (g) Integrity %
retenu
Adhesion
% enrobage
A 4 0 – 0.7 90 – 100 90 – 100
B 3 0.7 – 1.0 75 – 90 75 – 90
C 2 1.0 – 1.3 50 – 75 50 – 75
D 1 1.3 – 2.0 10 - 50 10 -50
Microsurfacing
Formulation study

17. Fields of application

18. Microsurfacing
Field of application
Wearing course, maintenance or new
pavements
(highways, urban and rural streets, residentials)
Bicycle lanes, Parkings
Cape Seal : Chips seal + Microsurfacing
Dangerous zones ‘’accidents’’
(Gap graded formulation)
Colored surfaces

19. Microsurfacing
Selection Criterias
Security and noise efficiency
Reduction of aggregates loss (in comparison of chips seal)
No bleeding
Less noisy
Service life
Long term skid resistance
Trafficable at early age
Esthetic
Improvement with circulation (joints)
Possibilty of Coloration

20. Preparation works
No milling required (ruts less than ¾ inch)
No tack coat required
Works duration
Reopening to the traffic very fast
Less traffic interruption
Microsurfacing
Selection Criterias

21. Pavement
Condition
Time (Years)
Slurry
Seal Micro-
Surfacing
Chip Seal
Hot-In Place /
Cold-In Place
Mill & Overlay
Reconstruction
REDUCE
RECYCLE
RE-USE
“The Right Product, On the Right Road, At The Right Time”
FDR
Cape Seal
Note: Selection of product is very
dependent on existing surface
deterioration and traffic requirements.
Microsurfacing
Selection Criterias

22. Microsurfacing
Limits of application
Unefficient (single layer) against crack reflection
No reprofiling and reinforcement effects
Consider the pavement structure capacity
Double application always better

23. Microsurfacing
Preparation and intervention
Support preparation
Deformations and defects survey
Treatment in fonction of the support condition
Structural deficiencies
Correction before microsurfacing application
Superficials defects: stripping / raveling
Corrections of deformations of the supports without
showing any structural deficiencies
Microsurfacing interventions =
Number of layers in function of the
déformations

24. Microsurfacing
Preparation and intervention
Choice of treatment in function of Rutting
deformation:
Deformation less than ¼ inch;
Deformation between ¼ and ¾ inch;
Deformation more than ¾ inch

25. Microsurfacing
Preparation and intervention
Deformation less than ¼ inch;
Crack filling of cracks over 1/4 inch
Preparation of the support
Cleaning of the surface
Microsurfacing application:
Double layers (always better)
Or single application if the support have no deformation

26. Microsurfacing
Preparation and intervention
Protection of the utilities (covers, joints)
Drains covers protected by papers or plastic film

27. Microsurfacing
Preparation and intervention
Existing Markings:
Stripping of thermolastic markings
Emulsion application over paint markings

28. Microsurfacing
Preparation and intervention
Cleaning of the surface:
Sweeping of the surface to remove any debris
Water projection if necessary

29. Microsurfacing
Preparation and intervention
Application of the Microsurfacing (deformation < ¼ inch):
A first correction layer of 5 to 8 kg/m² ( 9 to 14 lb/sy) « Scratch coat »
A final application of ± 10 kg/m² (18 lb/sy)
Steel edge
Full width

30. Microsurfacing
Preparation and intervention
Application of the Microsurfacing (deformation between
¼ to ¾ inch):
Cleaning of the surface
Preparation of the support
Rut filling with microsurfacing
Double application of Microsurfacing (always better) or single
application
Scratch coat 5 to 8 kg/m² ( 9 to 14 lb/sy)
Wearing course ± 10 kg/m² (18 lb/sy)

31. Microsurfacing
Preparation and intervention
Ruts filling with microsurfacing;
In condition of:
Presence of wearing;
The ruts deformation are stabilized
The support have a good enough structural capacity
No alligator cracks
The ruts have to be fill with adapted microsurfacing mix formulation

32. Microsurfacing
Preparation and intervention
Ruts filling with Microsurfacing
The Rutting box

33. Microsurfacing
Definitions – Rates of application
ISSA A-143 Rate of application
Québec
Type II Type III Type 1 et type 2
Suggered rates of application (Kg/m²)
Without ruts fill 6 to 11 Kg/m²
11 to 20 lb/sy
8 to 16 kg/m²
9 to 30 lb/sy
8 to 12

34. Microsurfacing
Recommanded Rates of application from ISSA
Rate of application
(Type III only)
(For every mm of microsurfacing mix, add 3 to 5 mm as a crown
to allow for compaction under traffic)
Ruts depth
12 - 19 mm 11 to 16 kg/m²
19 - 25 mm 14 to 19 kg/m²
25 - 32mm 15 to 21 kg/m²
32 - 38 mm 17 to 22 kg/m²
Rate of application
(Type III only)
(For every inch of microsurfacing mix, add 0.125 in to 0.25 in as a
crown to allow for compaction under traffic)
Ruts depth
0.5 – 0.75 inch 20 to 30 lb/yd²
0.75 – 1.00 inch 25 to 35 lb/yd²
1.00 – 1.25 inch 28 to 38 lb/yd²
1.25 – 1.50 inch 32 to 40 lb/yd²

35. Microsurfacing
Preparation and intervention
Application of Microsurfacing (deformation > ¾ inch):
Reprofiling with cold milling or micro milling;
Cleaning of the surface;
Double application of microsurfaing:
Scracth coat of 5 to 8 kg/m² (9 to 14 lb/sy;
Wearing course of ± 10 kg/m² (18 lb/sy)

36. Gap Graded formulations

37. Components of Gap graded micro-surfacing
Binder : PMA emulsion
Aggregates: Gap-Graded gradation
Selected Fibers
Type of fibers
Dosing of fibers
Effect of fibers on the mix
The very dense fiber network significantly modifies the rheological behavior
of the mix, giving short and long-term benefits.
The addition of fibers increases the apparent viscosity of the mix. The
apparent viscosity increases by a factor of ten. This fibers network avoid any
segregation in the spreader box, allowing the use of special Gap graded
gradation.
Microsurfacing with Gap graded gradation

38. Aggregate : Example of gradation and quality tests
TEST TEST METHOD SPECIFICATION Value
Sand equivalent Value of soils
and fine aggregates
ASTM D2419 65 % minimum 66%
CPP (Polissing Coefficient by
projection) PVN
LC 21-102 0.45 0.56
Resistance to degradation in
Micro-deval machine
LS 609 16 % 8.5%
0
10
20
30
40
50
60
70
80
90
100
0.01 0.1 1 10
Sieves (mm)
Passing(%)
ISSA Type III gradation
0
10
20
30
40
50
60
70
80
90
100
0.01 0.1 1 10
Sieves (mm)
Passing(%)
Gap graded 0-6 mm
Microsurfacing with Gap graded gradation

39. Surface characteristics
Macro-texture, average texture depth, Sand patch test (initial)
0/6 ATD around 0.8 mm
0/10 ATD > 1 mm
Skid resistance (initial)
BFC at 40km/h > 0,50
BFC at 120km/h > 0,35
BPN > 0.70
Higher the grading, higher the BFC
Microsurfacing with Gap graded gradation

40. A Gripfibre® 0/10 has been laid on a section of A71 highway (2 km).
Braking-force coefficient has been measured after 6 and 18 months.
GripfibreGripfibreGripfibreGripfibre®®®® productproductproductproduct
0.1
0.2
0.3
0.4
0.5
0.6
0.7
40 50 60 70 80 90 100 110 120
Braking-forcecoefficient(BFC)
Speed (km/h)
Evolution of braking-force coefficient on motorway A71 after 6 and 18 months of service
BFC after 6 months on slow lane
BFC after 18 months on slow lane
BFC after 6 months on fast lane
BFC after 18 months on fast lane
Upper and bottom thresholds
measured on national roads
High skid resistance microsurfacing mixHigh skid resistance microsurfacing mix

41. The use of synthetic fibers:
Synthetic organic fibers
0.1 to 0.2% in relation to aggregates
Thin and long (4 to 6 mm)
Several million of fibres per m²
Pretreated for a better dispersion
Use of a Fiber Cutter system
Laying made easier
Against segregation and trickles
Improved performances
Allow gap-graded formulas to be used
Ensure a better long lasting skid resistance
Microsurfacing with Gap graded gradation

42. Fibers specially designed dosing unit:
Ready to use Fibers
Microsurfacing with Gap graded gradation

43. A143 Recommended performance guideline:
Microsurfacing with Gap graded gradation

44. Synthetic organic fibers
0.1 to 0.2% in relation to aggregates
Thin and long (4 to 6 mm)
Several million of fibres per m²
Laying made easier
Against segregation and trickles
Improved performances
Allow gap-graded formulas to be used
Ensure a better long lasting skid resistance
Microsurfacing with Gap graded gradation

45. Résults Requir.
mixing time at 25 °C(sec) 210 120 min
setting time (min) 13 -
Résults Requir.
cohesion at 30min (Kg.cm) 15 12 min
cohesion at 60min (kg.cm) 22 20 min
Preblended aggregates
Portland cement
Premix water
retarder
Emulplast EC(04-2)
Résults Requir.
1hour soak (g/m2) 257 538 max
6 days soak (g/m2) 691 807 max Asphalt content (based on aggregates)
OTHERTESTS
Résults Requir. Résults Requir.
Excess Asphalt by LWT (g/m2) 257 538 max Specific gravity after 1000 cycles of 57 kg 1,978 2,10 max
Wet Stripping (%) 95 + 90 min Classification Compatibility BAA AAAou BAA
Lateral Displacement (%) N/A 5 max
4 - 6mm - selecteg aggregates - New-Brunswick
0-2mm- selecteg aggregates - New-Brunswick
MIXING- CONSOLIDATION
WET COHESION
WET TRACKABRASIONLOSS
AGGREGATES
MIX DESIGNAT 20°C(Based on aggregates)
MIXFORMULATION
Microsurfacing with Gap graded gradation
Synthetics Fibers

46. Modifications proposal:
4.2 Aggregate
4.2.3 Gradation
Microsurfacing with Gap graded gradation

47. 0
10
20
30
40
50
60
70
80
90
100
0.01 0.1 1 10
Sieves (mm)
Passing(%)
Gap graded TYPE IV
Microsurfacing with Gap graded gradation

48. Recommandations:
The rut fill have to be realized with type III mix;
Recommandation to always realized a type III scratch coat before
the application of Type IV mix wearing course;
The fibers dosing unit have to be specially designed to this
application;
Aggregates gradation for gap-graded mix:
Blend of 0 -1/8 and 1 /4 - 3/8:
Microsurfacing with Gap graded gradation

49. Crack relief system with using
Microsurfacing

50. Hot applied Membrane + Fibrous microsurfacing
Crack inhibitor system FLEXIPLAST®

51. Support fissuré
Nouvelle couche de roulement
} Flexiplast
• Very efficient system against crack rising type :
• Thermal shrinkage
• Longitudinals, transversals
• polygonals
• Efficient System on every kind of support, without structural weakness.
• Support Waterproofing effect.
• Good bonding between HMA layers.
Crack relief system FLEXIPLAST®
New wearing course
Cracked support

52. Crack relief system FLEXIPLAST®
-5°C, after > 320 000 cycles, no
crack rising,
-Horizontal displacement 24 µm
-Vertical displacement 19 µm
+ 5°C, after >178 000 cycles, no
crack rising,
-Horizontal displacement 111 µm
-Vertical displacement 18 µm

53. Crack inhibitor system FLEXIPLAST®
- Comparison of systems efficiencies at -5°C

54. Colored microsurfacing

55. Red colored
Conventional bitumen emulsion
Aggregates (pink porphyre)
Iron oxide pigment
COLORED MICRO-SURFACINGS

56. RD 14 Cazouls-les Béziers (34), in 2005
Red colored
COLORED MICRO-SURFACINGS

57. Footpaths in Zénith – Clermont Ferrand (63) – 2004
Red colored
COLORED MICRO-SURFACINGS

58. Red colored
COLORED MICRO-SURFACINGS
Microsurfacing before Abrasion test Microsurfacing after Abrasion test

59. Private property access – Sigogne (16)
Beige
Use of synthetic binder emulsion
COLORED MICRO-SURFACINGS

60. Green
Use of synthetic binder emulsion or Conventional emulsion
COLORED MICRO-SURFACINGS

61. Green colored
COLORED MICRO-SURFACINGS
Microsurfacing before Abrasion test Microsurfacing after Abrasion test

62. Orange
Synthetic emulsion
Selected aggregates
Iron oxide
COLORED MICRO-SURFACINGS

63. Futurs developments

64. Use of synthetic binder (colored mix)
Special formultion for ruts filling
Use of recycling asphalt pavement RAP as aggregate
50-75% of RAP
Less emulsion
FUTURS DEVELOPMENTS

65. Janvier 2011 - page 65
Thanks for your attention