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Innovative Methodologies

for Road Surface Maintenance in Japan;

HIR (Hot In-place Recycling),

Hot In-place Thin Overlay and

Hot In-place Transforming

National Conference on Highways Construction Technology

at Hyderabad

July 15, 2016

HIR Target Work Fields (Red-Framed)

Type of Activity Increase

Capacity

Increase

Strength

Reduce

Aging

Restore

Serviceability

New Construction ○ ○ ○ ○

Reconstruction ○ ○ ○

Major (Heavy)

Rehabilitation ○ ○

Structural Overlay ○ ○

Minor (Light)

Rehabilitation

Preventive

Maintenance ○

Routine

Maintenance

Corrective

(Reactive)

Maintenance

Catastrophic

Maintenance

Pavement Preservation Guidelines

○

Pavement

Preservation

Table Source : US FHWA

○

○

○

○

○

○

○

○

2

Green Technology for Sustainable Highway Reconstruction

Hot In-place Recycling

•Economics Including Construction Cost & Long Life

• Resource Saving

• Safety Improvement

• CO2 Emission Reduction

Innovative Method beyond the Conventional Method

3

Very Poor

Poor

Fair

Good

Very Good

Optimum Rehabilitation Point

Accumulated Axile Loads

Rehabilitation with Thin Overlay by HITO

Pavement Condition Sharply Drops

Will Cost 2 to 3 times as much as at Optimum Rehabilitation Point

Original Condition

Pavement Life

Reconstruction or Major Rehabilitation

Existing Pavement

Pavement Life-Cycle Prolongation through Keeping Condition Approach

Pavement Condition

Rehabilitation with Thin Overlay by HITO

Pavement Management System for Sustainable Road Construction

Features of asphalt mixture; Recyclable,

Easily softend by heater at 60 to 80 ℃ with aggregates not damaged.

What is HIR?

Heating to Soften Milling of Heated

Asphalt Mix

Adding

of New

Ad-Mix

Mixing Laying

down Compacting

Resource Saving Reuse 100% of existing asphalt mixture (Usually 70%

reduction of new asphalt mixture compared with

conventional method)

Economics More economical than prevailing conventional Mill & Fill

method

Environment No smell, no smoke, no fire under usual operation

Reduction of CO2 emission (40% reduction compared with

conventional Mill & Fill method)

Work Speed 5m/min on average

HIR Mill & Fill CIR

○ ○ ○

○ ○ -

Alligator ○ ○ ○

Longitudinal ○ ○ ○

Transverse ○ ○ ○

○ ○ -

○ ○ -

○ ○ -

Loosening Hard Milling or Excavation Hard Milling

Not Crushed Crushed and Disposed Crushed

100% Onsite Reuse Replace 100% Onsite Reuse

Unchanged - Changed

Not Required Tack Coat Cleaning and Tack Coat

Not Required By Truck Not Required

Bleeding

Slipperiness

Existing Asphalt Mixture

Aggregate in Use

Re-habilitation Method

Ty

pe

of

Pav

emen

t D

istr

ess

Ch

arac

teri

stic

s

Mixture Gradation

Pre-Treatment Under Layer

Transport Reclaimed Materials to Plant

Cracking

Rutting

Unevenness (Corrugation)

Raveling

Mico Surfacing

(Slurry Seals)

△

×

×

×

×

○

△

○

-

-

-

-

Cleaning and Tack Coat

Not Required

Why HIR Preferred?

- Usually not used Suitable × Unsuitable

* *

*: depending on the damaged condition

Superb Hot Air Heating System developed by Green ARM

Hot Air Heating System;

Easy Supply of Fuel on Site for Surface Heating,

Diesel: Much Safer Fuel than Propane,

Hot Air Heating; Gentle and Even Heating,

Step-less Adjustment of Heating Width HEATER (Green ARM’s Heater)

Surface Temperature after Heating

(Patent No. JP 4024293)

Heating

Advantages with Hot Air Circulation Heater

The performance has been confirmed through road heating work in Japan and California, US.

Smoke

Fire

Difference in ignition point

(Due to lower oxygen content)

0　　　　 2　　　 　4　　　 　6　　　 　8　　 　　10　　　 　12　　 　　14

400

300

200

100

tem

pera

ture

[℃]

Time[minute]

Surface

Smoke

Surface

The hot air circulation system The hot air circulation system

Fire

-20mm

-20mm

Infrared Burner Hot Air Circulation Heater

Road surface

Road

surface

1. Gentle Heating; No Overheating of Road Surface.

2. Homogeneous Heating of Road Surface.

3. No Smoke, No Fire, No Odor.

FIRE

SMOKE

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Hot In-place Thin Overlay

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Hot In-place Thin Overlay; New Easy Preservation Method

Crack

Rutting

Structural Profile

Patching

Light Distress

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Method of Hot In-place Thin Overlay (HITO)

Heating Scarifing Paving Compaction

Scarifier

New Hot Asphalt Mixture to be added

Existing Mixture

New Thin Overlay

Strong bonding

HITO Method

Road Heater

+

Scarifier

Delivery Truck

Asphalt Finisher

Steel Roller

Tire Roller

• Simple Repavement

• Short Train Composites

• Good Performance

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Key Technology of HITO

KAJIMA RO AD

Hot Air Circulation Scarifier

Existing Road Surface

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Characteristic Features of HITO Method

1. Combination of Efficient Heater & Conventional Paving Machine

2. Advance Mix Design Work Not Required ;

Ordinary Asphalt Mixture Available in the Market ready to be used for New Hot Asphalt Mixture to be added

Simple Work;

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HITO Work; Evaluation of Increase in Strength

Loading Test

Loading Test

with Wheel Tracking

Overlay

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HITO Work; Loading Test Result

Overlay （t=3cm）

Seal Infusion +

Overlay （t=2cm）

HITO Scarifying 2cm

Filling 2cm

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HITO Work; Cost Reduction

0

10

20

30

40

50

60

70

80

90

100

HITO (scarifing=2cm,filling=2cm)

HIR (milling=3cm,filling=2cm)

Overlay (t=5cm) Mill & Fill (t=5cm)

%

Construction Cost

Material Cost

+ R

eju

venato

r

51%

68%

84%

100%

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0

10

20

30

40

50

60

70

80

90

100

HITO HIR Mill & Fill (t=5cm)

%

Prduction of Asphalt Mixture

Material Delivery

Construction

Waste Delivery

HITO Work; CO2 Reduction

68%

100%

61%

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HITO Work; Summary

1. Life Extension

・ Sound conditions confirmed in more than 3 years

2. Cost Reduction

・ 49% Less than Mill & Fill

3. CO2 Reduction

・ 39% Less than Mill & Fill

4. Riding Quality Improvement

・ Elimination of Rutting

・ Elimination of Cracks

Site National Highway Route 77 in Okinawa

Hot In-place Transforming; Invented by Green ARM and Patented

Before(Dense) After(Porous)

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20

Binder

Rejuvenator

New Porous Asphalt 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 Course

Binder Course

13-5mm

Porous Layer

Hot In-place Transforming (Dense to Porous)

Dense Surface Mixture sieved, then transformed to Porous Mixture and

Mastic Mixture on Site by Double-lay Paver

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Site; National Highway Route 126 in Chiba prefecture, Japan

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

Construction Speed; 2.0m/min

Hot In-place Transforming Work done (Dense to Porous)

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HIT Work; 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 new asphalt mixture

Hot in Place

Transforming

Conventional

Method

16,756

11,688

30%down

do

Compaction

Tack coating

Kg-CO2

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Green ARM offers Green and Cost Saving Technologies

for Road Surface Maintenance and together with Terpl

Private Co., Ltd., India is ready to contribute

to Road Infrastructure Improvement in India

Thank you.

To be followed by NICHIREKI, which introduces its

bridge life prolongation technology.