CSIR reports ppt

1. Sustainability in Road
Construction
Dr Siksha Swaroopa Kar
Principal Scientist
CSIR-Central Road Research Institute

2. Sustainability: meeting our
own needs without
compromising the ability of
future generations to meet
their own needs.
Sustainability

3. MATERIAL
 In india, about 15,000 tonnes of aggregates are required
per kilometer of highway
 A typical NHDP of 60 km road improvement requires 20
lakh ton of material
ENERGY
 90,000 litres of fuel for drying and heating of aggregates
per kilometer of highway
 For a lead of 200 km (very common in North India),
180lakh litre of diesel in transportation is consumed
 Caused by heating of bituminous binder and HMA
 Amount of emissions doubles for every 10C increase in
production temperature
EMISSIONS
Road Construction Involves

4. Pavement Distressed: Well
designed and well
constructed-Traffic Loading
& Environmental Factor.
Maintenance: slow the
rate of deterioration by
addressing specific
pavement deficiencies
Rehabilitation: act of
repairing portions of an
existing pavement to reset
the deterioration process.
Reconstruction: act of
constructing new
pavement
Pavement Distress and its Correction

5. Reconstruction
Sub-grade
Sub-Base
Base

6. • Material Consumption: bitumen &
aggregate
• Disposal issue of old pavement : Waste
Generation
• Energy Consume
• Longer Time required for construction

7. Rehabilitation: Overlaying
Sub-grade
Sub-Base
Base

8. • Pavement Thickness Problem
• Material Consumption

9. Rehabilitation: Recycling
Sub-grade
Sub-Base
Base

10. Hot Mix Recycling Cold Mix Recycling
In place Recycling Full Dept Recycling
Different Recycling Methods
Sub-grade
Sub-Base
Base
Sub-grade
Sub-Base
Base
Can be
upto any
depth

11. As per IRC 120

12. ✔ FDR involves recycling existing bituminous pavement and
underlying pavement layer(s) into a new base layer
✔ Process – Excavating and pulversing in-situ pavement
(excluding subgrade), blending with cementitious binder, water,
corrective or additional aggregates (if needed) as per mix design
to produce a cemented / stabilised base
What is FDR ?

13. Which Roads are Suitable for FDR
⮚ Roads considered for up-gradation – Application of FDR
technique for existing flexible pavement ONLY after it
completes design life of 10 years
⮚ When existing pavement has more than 50% area
distressed – Excessive cracks (Longitudinal, Transverse,
Alligator) deep rutting, shoving, slippage, extensive
potholes and patching, Worn out pavement, ravelling, base
or sub-base failure requiring reconstruction
⮚ Existing rural road pavement comprises of low grade
materials like brickbats, soft aggregates, marginal
materials, etc., which need to be replaced

14. Types of Binders for FDR
⮚ Pulverisation: No stabilizer
⮚ Mechanical Stabilisation
 Crushed Virgin Aggregate
 Reclaimed Asphalt Pavement Material
⮚ Chemical Stabilisation
⮚ Portland cement
⮚ Fly ash
⮚ Lime
⮚ Commercial chemical stabilisers
⮚ Bitumen Stabilisation
⮚ Bituminous emulsion
⮚ Foam Bitumen
U.K.Guruvittal
❑ Binders can be
adopted singly or in
combination
❑ OPC as FDR binder –
High strength gain,
and lower cost
❑ Low amount of fines
in pavement – Lime
and fly ash would not
be effective

15. ⮚ Need to gather as much historical
information as possible about the
distressed pavement: Original
design; Pavement layers and types
etc
⮚ Functional and structural condition
of pavement
⮚ Need to know about the Pavement
Crust Composition and Crust
Thickness
⮚ Traffic type and traffic level
analysis
⮚ Material properties i.e sub-grade;
Assessment of Pavement before
Construction

16. Chemical Stabilisation using
Cement

17. Pavement Sample Collection
⮚ 0.5 m x 0.5 m (Min) test pit
for every km length of road
⮚ Collect 100 to 150 kgs of
pavement material from
each pit
⮚ Leave out pavement layer
which is not to be recycled
⮚ Material from different pits
to be combined, reduced to
about 300 to 350 kgs by
quartering and transported
to lab

18. Material Testing – Subgrade
⮚ At least 3 samples per km for index property tests, one CBR
test per km or for each type of soil, whichever higher
⮚ CBR test to be carried out at field density and field moisture
content after recession of monsoon
Tests on Reclaimed Pavement
✔ Particle size analysis
✔ Liquid limit (LL) and Plastic limit (PL)
✔ Modified Proctor Compaction test
✔ Compressive strength test
✔ 15 cm cube moulds, Needle Plate Compactor usage
✔ UCS & Proctor tests
✔ Durability Test - Method 1 (Moderate Climate) or Method
2 (Large variations in temperature and climatic condition)
✔ Cement and Water Tests – Potable water

19. Mix Design for FDR Process
⮚ Determining suitable percentage of cement and water to be
admixed before compaction – Mix design
⮚ Pulverised pavement sample to meet gradation limits,
Otherwise mechanical stabilisation required

20. Gradation of Pulverised Pavement
⮚ Changes required for cement stabilised material gradation
IS Sieve % passing
53 mm 100
37.5 mm 95 – 100
19 mm 45 – 100
9.5 mm 35 – 100
4.75 mm 25 – 100
600 micron 8 – 65
300 micron 5 – 40
75 micron 0 – 10
PCA, 2006
PCA, Cement Treated Base, 2006
Gradation Limits for
Cement Stabilisation
Particle Size
IS Sieve Min % passing
75 mm 100
53 mm 95
4.75 mm 55

21. Mix Design for FDR
⮚ Select three different cement
percentages
⮚ Determine OMC & MDD for the
pulverised pavement sample admixed
with each percentage of cement
selected
⮚ For each cement content, 15 cm cube
moulds are prepared (Three Nos) for
compressive strength determination
0
2
4
6
8
0 1 2 3 4 5 6 7 8
UCS
(MPa)
Cement Content (%)
⮚ Samples to be moist cured for 7 days after casting
⮚ Cement content required to obtain 4.5 MPa compressive strength
after 7 days of moist curing, as determined from graph – Additional
moulds to be prepared at this cement percentage for durability test

22. Mix Design for FDR
⮚ Durability test (Method 1 or Method 2, as applicable in that
area) as per IRC SP:89 for 15 cm moulds at cement content
determined from compressive strength test
⮚ If durability test criteria is not satisfied, cement content
increased by about 0.5%, and durability test to be repeated
⮚ Cement Content – To get 4.5 MPa compressive strength (Min)
after 7 days curing and satisfies durability test

23. Construction Sequence
U.K.Guruvittal
1 Cement spreader
1
3 Pavement Recycler
3
4 Vibratory Padfoot Roller
5 Motor Grader
2 Water Tanker
4
6 Single-drum Vibratory Roller
5
6
2

24. STEP 4:
RECYCLING
STEP 5:
COMPACTION
STEP 2: CEMENT
SPREADING
STEP 1: SOIL/EXISTING
ROAD PROFILING
STEP 3: ADDITIVE
SPREADING
FDR: Construction Process
STEP1
•SOIL/EXISTING
ROAD PROFILING
STEP2
•CEMENT
SPREADING
STEP3
•ADDITIVE
SPREADING
STEP4
•RECYCLING
STEP5
•COMPACTION

25. STEP6
• GRADING
STEP7
• ROLLING
STEP8
• CURING
STEP9
•SAMI LAYER/ GEO
SYNTHETIC FABRIC
STEP10
• PRIME COAT
STEP11
• BC LAYER
STEP 7:
ROLLING
STEP 6:
GRADING
STEP 8: CURING
STEP 10: PRIME COAT
STEP 9: SAMI LAYER
STEP 11: BC LAYER
FDR: Construction
Process

26. Bitumen Stabilisation

27. Bitumen Stabilisation

28. 1
• Material Characterization
2
• Aggregate Gradation
3
• Foam Bitumen Characterization
• Determination of Optimum Moisture Content
• Determination of Optimum Foam Binder
Content
4
5
BSM using Foam Bitumen

29. 1
• Material Characterization
• Bitumen (As per IS 73)
• Penetration in between 60-150mm
• Aggregate (As per MoRTH Specification)
• RAP Material
• Total Binder Content and
• RAP Aggregate Gradation
• RAP Existing Moisture Content
• Ordinary Portland Cement as Active Filler
• Plasticity Index of material is less than 10
• Note : If PI is 10 to 16 , 1% hydrated lime to
be used and If PI> 16, 2% hydrated lime to
be used

30. 2
• Aggregate Gradation
The washed aggregate obtained in the binder extraction process is to be
dried in oven for 24 hours followed by sieve analysis for determination of
gradation.

31. Sieve size(mm)
79% 20% 1%
Blend
Specified
Limits
RAP stone dust
Cement
45 100 100 100 100 100
37.5 100 100 100 100 87-100
26.5 98 100 100 98 77-100
19 92 100 100 94 66-99
13.2 78 100 100 83 67-87
4.75 36 93 100 48 33-50
2.36 18 71 100 29 25-47
0.600 5 33 100 12 12-27
0.300 4 23 100 9 8-21
0.075 3 9 90 5 2-9
2
• Aggregate Gradation

32. Sieve
size(mm)
79% 9% 10% 1%
Blend Specifie
d Limits
RAP stone dust
20mm
aggregate Cement
45 100.0 100.0 100.0 100 100.0 100
37.5 100.0 100.0 100.0 100 100.0 87-100
26.5 93.0 100.0 100.0 100 94.4 77-100
19 83.0 100.0 93.0 100 85.7 66-99
13.2 71.0 100.0 60.0 100 72.8 67-87
4.75 39.0 100.0 7.0 100 41.9 33-50
2.36 29.0 94.0 3.0 100 33.0 25-47
0.600 15.0 62.0 1.0 100 18.7 12-27
0.300 9.0 36.0 1.0 100 11.5 8-21
0.075 3.0 8.0 0.0 90 4.0 2-9
2
• Aggregate Gradation

33. Expansion Ratio
• maximum volume of foam relative to the
original volume of bitumen
• a measure of the viscosity of the foam
indicates how the bitumen will disperse
Half-life
• time (seconds) for the foam to collapse to
half of its maximum volume
• measure of the stability of the foam
3
Foam Bitumen Characterization
Small quantity of cold water injected into hot bitumen
wherein the hot bitumen expands to about fifteen times or
more its original volume and forms a fine mist or foam,
known as Foamed Bitumen.

34. • Foaming water content (2-8% by weight of bitumen)
• Bitumen temperature (170-1900C)
• Bitumen Quantity : 500gm in an calibrated
cylinder and dip stick
3
Foam Bitumen Characterization

35. 3
Foam Bitumen Characterization
Expansion Ratio Half-Life Guideline
8-10 ≥ 6 IRC 120, 2015

36. • Determination of Optimum Moisture
Content
4
• Modified Proctor (AASHTO T180)
2.22
2.24
2.26
2.28
2.3
2.32
2.34
2.36
0 2 4 6 8
Dry
Density
(kg/cc)
Moisture Content (%)
Wadd = WOMC - RAP Moisture
where, Wadd = water to be added
W OMC= Optimum Moisture Content
RAPMoisture = Water present is RAP (RAP moisture Content)

37. Plant :
 Air pressure: 500 kPa
 Water pressure: 550 kPa
 Set up the optimum Foaming Parameter (Water
Content & Bitumen Temperature
 Set up the Bitumen Content (After Calculation)
• Determination of Optimum Foam Binder
Content
5

38. Foamed bitumen
RAP Fresh aggregates
Cement (1%)
1. Add Graded material in Mixing Unit
2. Add required water content
3. Mix it for 30 sec
4. Add the required bitumen conetnt
(2%, 2.5%, 3% by weight of total
aggregate)
5. Mix it for 1 min
6. Weigh 1200gm sample and compact
through Marshall compactor at 75
blows in each side (Total minimum 6
samples)
7. Curing : 72 haurs at 400C
8. Dry ITS Determination
9. Wet ITS Determination
• Determination of Optimum Foam Binder
Content
5

39. • Determination of Optimum Foam Binder
Content
5
2.5
2.7
2.9
3.1
3.3
3.5
3.7
3.9
4.1
4.3
1.2 1.6 2 2.4 2.8 3.2 3.6 4 4.4
ITS
Dry
(Kg/cm2)
Foamed Bitumen Content (%)
Wet ITS
Dry ITS
Dry ITS Wet ITS Guideline
≥ 225kPa ≥ 100kPa IRC 120, 2015

40. Where, P is the load (kg), d is the diameter in cm of the specimen; t is the
thickness of the specimen in cm. TSR is Tensile Strength Ratio
Moisture Resistance Requirement

41. BSM using Bitumen
Emulsion

42. 1
• Material Characterization
2
• Aggregate Gradation (As described in Foam
stabilization)
3
• Determination of Total Fluid Content
• Determination of Optimum Emulsion Content
4
BSM using Bitumen Emulsion

43. 1
• Material Characterization
• Emulsion (As per IS 8887
• SS2 Cationic Emulsion
• Aggregate (As per MoRTH Specification)
• RAP Material
• Total Binder Content and
• RAP Aggregate Gradation
• RAP Existing Moisture Content
• RAP Material
• Ordinary Portland Cement as Active Filler
• Plasticity Index of material is less than 10
• Note : If PI is 10 to 16 , 1% hydrated lime to
be used and If PI> 16, 2% hydrated lime to
be used

44. 2
• Aggregate Gradation
As described in previous section

45. 3
Determination of Total Fluid Content
• Bitumen emulsion and water are to be taken in the same ratio by
volume and mixed together to prepare the blend.
• Note: water to be added to the bitumen emulsion and not vice-
versa.
• Marshall Specimens of 100mm dia are to be prepared using
Marshall compactor with 75 blows in each side at 6%, 7%, 8% and
9% of blends (emulsion and water) by the weight of the mix.
• Dry densities are to be computed at each fluid content using the
following equation;
Ddd= Dry density in g/cc,
Dbulk= Bulk density in g/cc, (mass/volume)
FC = Fluid content by dry weight of aggregates.

46. 3
Determination of Total Fluid Content
1.56
1.58
1.6
1.62
1.64
1.66
1.68
1.7
1.72
5 6 7 8 9 10
Bulk
Densisty,
g/cc
Total Fluid Content, %
Total Fluid Content is 7.5% by weight of aggregate

47. 3
Determination of Optimum Emulsion
Content
• Blended RAP material, aggregate and filler are mixed with water
followed by emulsion.
• Marshall samples were prepared at 3.0%, 3.5% and 4.0% emulsion
contents by the weight of the total mix.
• Curing: 72 hours at 40°C
• Dry ITS Determination
• Wet ITS Determination
TFC,%
Water
Content,
%
Emulsion
Content, %
7.5 4.5 3.0
7.5 4.0 3.5
7.5 4.5 4.0

48. 3
Determination of Optimum Emulsion
Content
100
200
300
400
2.5 3 3.5 4 4.5
ITS,
kPa
Emulsion Content, %
Dry ITS Wet ITS
Dry ITS Wet ITS Guideline
≥ 225kPa ≥ 100kPa IRC 120, 2015

49. Available Codes
• IRC: 37 (2012) Guidelines for The Design Of Flexible Pavements
(Annexure IX)
• IRC: 120 (2015) Recommended Practice for Recycling Of
Bituminous Pavements (Appendix I to Annexure 1)
• TG 2, (2009) Bitumen Stabilised Materials, A Guideline for the
Design and Construction of Bitumen Emulsion and Foamed
Bitumen Stabilised Materials,

50. Surface after milling
Milling
CONSTRUCTION: Bitumen Stabilisation
7/26/2022 50
TIPCE 2019-IIT Roorkee

51. Spreading of cement
Fresh dust spread over milled surface
7/26/2022 51
TIPCE 2019-IIT Roorkee

52. Rolling operation
Cold in situ recycling
7/26/2022 52
TIPCE 2019-IIT Roorkee

53. Recycled surface before overlay Recycled road after overlay
7/26/2022 53
TIPCE 2019-IIT Roorkee

54. • Reduction in energy
requirements to heat
virgin aggregates &
binders
• Hedge against rising
bitumen prices & global
uncertainty which can
effect supply
• Reduces amount of virgin
aggregates & bitumen
which reduces material
costs
Advantage of Recycling

55. Savings with FDR
For 1.6 km, 7.3 m wide, 2 lane and 150 mm base layer

56. Concerns with Technology
• Which additive to be used?
• How much depth is to be reclaimed ?
• How much percentage of cement to be
added?
• What gradation to be adopted ?

57. Future Collaboration
Technical support during Field application
• Suitability of FDR
• Mix design
• Pavement design
• Long term Performance evaluation
• Environmental and cost impact analysis

58. Working together
• Performance evaluation of Ferro chrome slag
as an alternative material.
– WMM layer has been laid using ferro chrome slag

59. 59
THANK YOU

60. 60