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Pavement Recycling Technology for Highways in Japan

Presented at 1st ICTI 2008

April 24, 2008

Beijing, China

Hisashi Hosokawa CEO, Green ARM Co .,Ltd

Tokyo, Japan

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ContentsContents

1. History of Pavement Recycling in Japan

2. From Construction to Maintenance

3. Pavement Distress and Rehabilitation Method

4. Hot In-place Rehabilitation

5. Need for Porous Asphalt Pavement Recycling

6. Conclusion

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1. History of Pavement Recycling in Japan1.1 Pavement Recycling Technologies

70’ 80’ 90’ 00’ 10’

Pavement Recycling

Technologies

・Hot In-place Rcycling(1978)

・Hot Mix Asphalt Recycling　(Batch Plant) (1977)

・Hot In-place Transforming(2005)

・Hot In-place　Strengthening　(2007)

・Steel Deck Asphalt Recycling(2007)

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1.2 Volume of Asphalt Mixture

Source : MLIT Japan

-

10,000

20,000

30,000

40,000

50,000

60,000

70,000

80,000

90,000

100,000

85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 0 1 2 3 4 5 6Year

Vol

ume

of A

spha

lt M

ixtu

reth

ousa

nd to

n

Recycled Mixture New Mixture

5

0

10

20

30

40

50

60

70

80

90

100

55 60 65 70 75 80 85 90 94 95 96 97 98 99 0 1 2 3

Year

Pave

men

t Rat

io %

0

2000

4000

6000

8000

10000

12000

14000

Serv

ice

Dis

tanc

e Km

Pavement RatioService Distance

2. From Construction to Maintenance

Note: Target Length of Arterial High-standard Highway is 14000km

Present State of National Highway and Provincial Highway

Source : MLIT Japan

2.1 Pavement Ratio

6

40.0

45.0

50.0

55.0

60.0

65.0

70.0

1996 1998 2000 2002 2004 2006Year

Mai

nten

ance

Exp

endi

ture

Ove

r T

otal

Roa

d B

udge

t Exp

endi

ture

%

2.2　Maintenance Expenditure Ratio

Ratio = Maintenance / (Maintenance + New Construction)

Mai

nten

ance

Exp

endi

ture

Ove

rTo

tal R

oad

Bud

get E

xpen

ditu

re %

0.9% Increase Per Year

Source : MLIT Japan

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3. Pavement Distress and Rehabilitation Method

Rutting

Unevenness

Alligator Crack

Source : US Federal Highway Administration

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3.1 Pavement Preservation Guidelines

Type of Activity IncreaseCapacity

IncreaseStrength

ReduceAging

RestoreServiceability

New Construction × × × ×Reconstruction × × × ×Major (Heavy)Rehabilitation × × ×Structural Overlay × × ×Minor (Light)RehabilitationPreventiveMaintenance × ×RoutineMaintenanceCorrective(Reactive)Maintenance

×

CatastrophicMaintenance ×

Pavement Preservation Guidelines

× ×

×

PavementPreservation

Source : FHWA

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3.2 Rehabilitation Methods of Frequent Use

Mill & Fill HIR CIR Micro Surfacing(Slurry Seals)

○ ○ ○ △

○ ○ － ×

Alligator ○ △ ○ ×

Longitudinal ○ ○ ○ ×

Transverse ○ △ ○ ×

○ ○ － ○

○ ○ － △

○ ○ － ○

Hard Milling　orExcavation Loosening Hard Milling －

Crushed and Disposed Not Crushed Crushed －

Replace 100% Onsite Reuse 100% Onsite Reuse －

－ Unchanged Changed －

Tack Coat Not Required Cleaning and Tack Coat Cleaning and Tack Coat

By Truck Not Required Not Required Not Required

－ Usually not used

○ Suitable△ Probable

× Unsuitable

Pre-TreatmentUnder Layer

Transport ReclaimedMaterials to Plant

Aggregate in Use

Cha

ract

eris

tics

Existing Asphalt Mixture

Mixture Gradation

Raveling

Bleeding

Slipperiness

Type

of P

avem

ent D

istr

ess

Rutting

Unevenness(Corrugation)

Cracking

Re-habilitation Method

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3.3 Comparison of Rehabilitation Methods in Terms of Energy Consumption

Source : Katawaki.S, The Expansion of New Civil Engineering Materials

0.0 1.0 2.0 3.0 4.0 5.0

Hot In-placeRecycling

Hot Mix AsphaltRecycling(Mill & Fill)

NewConstruction

Energy Consumption, Million kcal/m

Material ProductionMachine OperationDelivery of MaterialsUse for Other Purpous

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4. Hot In-place Rehabilitation 4.1　Address Surface Distress (Hot In-place Recycling)

ReRe--PavePave

ReRe--MixMix

New AsphaltMixtureRejuvenator Compaction

Spreading

MillingHeating

Mixing

New AsphaltMixture Compaction

Spreading

Milling & Mixing(Rejuvenator)

Heating

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ReRe--PavePaveHokuriku Expressway(1980Hokuriku Expressway(1980ｓｓ))

ReRe--MixMixNational Highway Route 41(1980National Highway Route 41(1980ｓｓ))

Source : Association for Advancement of Surface Recycle Technology

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4.2 Applicable Area (Hot In-place Recycling)

Type of Activity IncreaseCapacity

IncreaseStrength

ReduceAging

RestoreServiceability

New Construction × × × ×Reconstruction × × × ×Major (Heavy)Rehabilitation × × ×Structural Overlay × × ×Minor (Light)RehabilitationPreventiveMaintenance × ×RoutineMaintenanceCorrective(Reactive)Maintenance

×

CatastrophicMaintenance ×

Pavement Preservation Guidelines

× ×

×

PavementPreservation

Source : FHWA

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4.3 Address Structural Distress (Hot In-place Strengthening)

BinderRejuvenator

New Asphalt Mixture

Compaction

Milling Beyond Surface Layer

Heating

Mixing ｆor Lower Layer

New Aggregates

Surface　CourseBinder Course

New Technology

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4.4 Applicable Area (Hot In-place Strengthening)

Type of Activity IncreaseCapacity

IncreaseStrength

ReduceAging

RestoreServiceability

New Construction × × × ×Reconstruction × × × ×Major (Heavy)Rehabilitation × × ×Structural Overlay × × ×Minor (Light)RehabilitationPreventiveMaintenance × ×RoutineMaintenanceCorrective(Reactive)Maintenance

×

CatastrophicMaintenance ×

Pavement Preservation Guidelines

× ×

×

PavementPreservation

Source : FHWA

New Technology

16

0

10

20

30

40

50

60

70

80

90

100

89 90 91 92 93 94 95 96 97 98 99 0 1 2

Year

Por

ous

Pav

emen

t Con

stru

ctio

n V

omum

e m

illion

m 2

Porous Pavement

5. Need for Porous Asphalt Pavement Recycling

Source : MLIT Japan

5.1 Construction Volume

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5.2 Advantage of Porous Asphalt Pavement

Source : MLIT Japan

80

82

84

86

88

90

92

94

96

98

100

Dense Air void=4%

Porous Air void=10%

Porous Air void=15%

Porous Air void=20%

Tra

ffic

nois

e level (d

B)

0

500

1000

1500

2000

2500

3000

Dense Asphalt Porous Asphalt

Num

ber

of tr

affic

accid

ents

for

one

year

84%down

466sites∑=312km

Dense asphalt Porous asphalt

Traf

fic N

oise

Lev

el (d

B)

Num

ber o

f Tra

ffic

Acci

dent

s fo

r One

Yea

r

Traf

fic N

oise

Lev

el (d

B)

Decrease of Traffic Accidents Noise Absorption of Porous Asphalt Concrete

Air Void=4% Air Void=10% Air Void=15% Air Void=20%

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BinderRejuvenator

New PorousAsphalt Mixture

Compaction

Milling of Surface

Heating

Mixing for Lower Layer•More than 13mm•Less than 5mm

Sieve

Mixing for Porous Layer Mastic Layer

Dense Surface CourseBinder Course

13-5mm

Porous Layer

5.3　Hot In-place Transforming (Dense to Porous)

New Technology

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Date September, 2006

Site National Highway Route 126 in Chiba Prefecture

Construction Volume 3,000㎡　（Length：400m×2Lane）　　

Construction Speed 2.0m/min

Hot In-place Transforming Project (Dense to Porous)

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Date September, 2005

Site National Highway Route 77 in Okinawa

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• Core and Marshall Test Results (National Highway Route 77 in Okinawa)

Porous Asphalt 30ｍｍ

Mastic Gap Asphalt 35ｍｍ

Hot joint

Marshall Test Results of Porous Asphalt Concrete

Core Sample taken after Construction

35mm

35mm

SpecificationsMeasureｄ

Value

MarshallStability (kN) > 3.5 4.0

Flow Value (mm) 2.0-4.0 2.6

Air Void (%) > 15 20.0

Coefficient ofPermeability (cm/s) > 0.01 0.198

Dynamic Stability byWheel Tracking Test (Pass/mm) > 3000 4400

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• Reduction of CO2 Emission

0

4000

8000

12000

16000

20000

kg-CO2

HI-T工法 従来工法

Pre-Heater

Heater-Miller

Separator

Mixer-Paver

Compaction

Producing & deliveries

of new aggregate

Cleaning + Removing

Milling

Manufacturing &delivering of newasphalt mixture

Hot in Place Transforming

Conventional Method

16,756

11,688

30%down

Compaction

Tack coating

Kg-CO2

23

0

10

20

30

40

50

60

70

80

90

100

81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 0 1 2

Year

Por

ous

Pav

emen

t Con

stru

ctio

n V

olum

eM

illio

n m

2

0

500

1000

1500

2000

2500

3000

Hot

In-p

lace

Rec

yclin

g C

onst

ruct

ion

Vol

ume

Tho

usan

d m

2

Porous Asphalt Pavement

Hot In-place Recycling ofDense Grade Asphalt

5.4 Need for Hot In-place Recycling of Porous Asphalt

Hot In-place Recycling(Porous Asphalt → Porous Asphalt)

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New Technology5.5 Hot In-place recycling of Clogged Porous Asphalt

BinderRejuvenator

New Asphalt Mixture

Compaction

Milling of Surface

Heating

Asphalt Coated Sandand Filler and Extra

Substance Having Caused Clogging

Sieve

Mixing for Porous Layer Thin Layer

Porous Surface CourseBinder Course

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6. Conclusion

New Technologies Now Available to Cope with Increasing Needs for

Safety,Energy Saving,Resource Saving,Green House Gas Reduction,Asset Management