Reinforced Bitumen Emulsion

South African Road Pavement Structure Example:

Wearing Course:Asphalt/Seal

(bitumen & stone)

Base Course(Crushed stone or bitumen plus

stone/gravel)

Sub-base(natural gravel or natural gravel plus

cement stabilization)

Selected Layers andSub-grade(Gravel or sand)

• Bitumen emulsion is a by-product of the crude oil refining process which is chemically suspended in water.

• Well known and documented in road construction industries for many decades.

• It is mixed with aggregates at ambient temperature into an aggregate and compacted.

• Improves water resistance and shear strength (cohesion) of aggregates and is used to construct roads.

• As it forms individual spot welds between particles, acting as an improved granular material and fails through deformation.

What is Bitumen Emulsion Stabilization?

Materials for the Binding of granular materials: Bitumen:

– Asphalt- Surface seals- Stabilization

Ecobond: – modified bitumen emulsion for stabilization

and bitumen/asphalt base

Cement: – Concrete

- Cement stabilization

The product development involved several industry experts, 4 PhD scientists (MIT, Wits,

Cambridge & Texas) and many field tests.

Ecobond results have been published in two peer reviewed engineering journals.

Ecobond was first used in a South African government project in 1996, and is currently

specified in several government projects.

Ecobond is a patented combination ofBitumen Emulsion

and Synthetic Resin.

The 5 Ecobond Products:

The 5 products have different chemical combinations and design

methods.

Some products can be used in combination with each other.

Ecobond Products for roads:Ecobond Bitumen

Stabilized Materials EBSM

Resin modified bitumen emulsion stabilization. Rubbery flexible binder.

Nearly identical to bitumen emulsion stabilization.

Resin acts as active filler.

Chemical breaking of emulsion.

Finer dispersal of modified bitumen.

Higher wet strength.

Effectively allows for more durable BSMs at the same price.

Ecobond Products for roads:Ecobond 5050

Bound or partially bound base courses

Empirically designed system based on cemented base course principles from TRH and SAPDM over the past

18 years.

Higher stiffness binder, still elastic. Binder bonds chemically to aggregate.

Relatively thin pavement structures

Very high water resistance

Very effective when used with surface seals (e.g. surface deflections and water resistance).

Used for very low cost roads or very durable roads.

Ecobond Products for roads:Ecobond aggregate

and material modification

(EB Mod)

Ecobond modification of crushed stone, natural gravel, sands, etc. is utilized to:

• Improve Shear Strength by increasing the cohesion

without reducing the angle of internal friction• Reduce moisture sensitivity

• Testing: Triaxial shear

Applications:• Sub bases

• Selected layers• Crushed stone base courses

• Gravel road wearing courses when combined with Ecobond spray-on applications

Ecobond Products for roads:Ecobond Wearing

Courses

• Ecobond Wearing Courses stabilize the top layer (wearing Course) of Gravel Roads.

• a durable water resistant wearing course that reduces aggregate loss that occurs due to traffic and

environmental conditions.

• Testing involves laboratory abrasion and erosion tests compared to untreated control samples.

Applications:• Government Gravel Roads

• Road shoulders• Mine Haul Roads

• Game Farms

Ecobond Products for roads:Ecobond Spray on

Erosion control

• Similar to bitumen emulsion dust inhibition• Modified to be less temperature sensitive and

penetrates into the surface to form a miniature base/support layer for the modified bitumen.

• Un-trafficked areas lasted up to 7 years• Lightly trafficked areas up to 5 years• Medium or Heavily trafficked areas can be applied

daily, weekly or monthly

Applications include:• Reducing sources of particulate material for health

reasons• Reducing the amount of re-gravelling for

government unpaved roads• Dust and erosion control for mines and industry

Ecobond BSM system

Ecobond BSM binder and 80/100 bitumenHeated to 50 degrees Celsius

Ecobond BSM remains rubbery

Normal Bitumen becomes visco-

elastic

• Act like granular materials, but stronger

• Fine materials can be treated for low volume base courses or for use in lower layers (Sub Base, SG)

• Coarse materials typically require less binder to achieve sufficient strength/stiffness

• Most important aspects of aggregates: Grading Modulus, Plasticity Index and material < 0.075mm sieve.

• Rate of deformation depends on layer thickness, stiffness/strength class, level of support and traffic volume.

Rules of thumb for Ecobond BSMs:

Ecobond BSMs are classified into three classes, depending on the quality of the aggregate/material and the design traffic. The three classes are:

• EBSM1: high shear strength, used for design traffic > 6 MESA. Aggregate is typically a well graded crushed stone or reclaimed asphalt (RA).

• EBSM2: moderately high shear strength, for < 6 MESA. Aggregate used is typically be a graded natural gravel or RA.

• EBSM3: This material typically consists of soil-gravel and/or sand, typically stabilised with higher binder contents. As a base course layer, the material is only suitable for design traffic applications of less than 1 MESA.

Strength categories of Ecobond Bitumen Stabilized materials

Suitable Aggregates – EBSM stabilization

EBSM 1 – G1 to G4EBSM2 – G4 to G6EBSM 3 - = <G6

Suitable Material (approx.):

Test or indicator Material Design Equivalent Material Class Not suitable for EBSM1 EBSM2 EBSM3 EBSM stabilization

Soaked CBR (%) CS (98%) >80 >25 >10 <10

NG(95%) >25 >10 <10

P0.075 (%) CS (98%) 2 to 15 >15 NG(95%) 5 to 25 25 to 40 >40 GS 5 to 20 15 to 30 >30 SSSC 0 to 20 >20

Plasticity Index CS (98%) <10 <12 NG(95%) <6 <12 <15 >15 GS <11 <15 >15 SSSC <15 >15

Grading Modulus NG 2.0 to 3.0 1.2 to 2.7 GS 1.2 to 2.5 0.75 to 2.7 <0.75

Technical Data

Level 1 & 2 BSM ITS - TG2 2009:

Level 1 tests:

Level 2 tests:

ITS = Indirect Tensile Strength, strength values in KPa

Wet/Soaked tests are submerged for 24 hours before being crushed

Standards for bituminous base course stabilization

Pavement Design Examples: up to 1MESA

Key Points:• What is the road

Category?• What is the traffic

volume?• What is the CBR of the

foundation layers?

Then use catalogue for pavement layer design guidelines

Independent SANAS Accredited Laboratory testing

Has shown that Ecobond BSM can attain double the wet strength

Of foamed bitumen stabilization at the same price:

Ecobond Tests TG2: Level 2 vs. Foam bit.

Ecobond 5050 Boundor partially bound system

Ecobond 5050/Partially bound system features:

• Strength: C4 < 1,5 MPa, C3 < 3 MPa, C2 < 6 MPa, C1 < 12 MPa equivalent soaked UCS has been attained.

• Water resistance: up to 6,35 x 10-7 cm/s water impermeability, 2 – 6 times less water absorption than standard bitumen stabilization samples have been recorded.

• Elasticity & tensile strength: Increases resistance to permanent deformation, but can bend and return.

• Workability with a wide variety of soils, even fine sand. This can often reduce material import costs and construction time. Increases cohesion and friction angle.

Design method is similar to cemented base courses (e.g. TRH4) without carbonation and stabilization cracking.

2% / 0% 2% / 0.5% 2% / 2%0.00%

1.00%

2.00%

3.00%

4.00%

5.00%

2.00% 2.00% 2.00%

0.00%

0.50%

2.00%

Ecobond to Bitumen Ratio

Gross Bitumen % / Ecobond %(2% = Residual Bit. 1.2%)

To

tal D

osa

ge

by

So

il M

ass

0.00% 0.50% 1.00% 1.50% 2.00%0

1

2

3

4

5

6

7

8

0.8

3.9

6.9

Ecobond Reinforced Bitumen UCS

Added Ecobond Polymer Dosage

UC

S (

MP

a)

Ecobond 5050 Compressive Strength:

0.0% 0.5% 1.0%0.00%

1.00%

2.00%

3.00%

4.00%

5.00%

6.00%

7.00%

8.00%

9.00%

10.00%

8.70%

1.50%

0.40%

Water Absorbtion

H2O Absorbed

Added Ecobond Polymer Dosage

% w

ater

abs

orbe

d pe

r ow

n m

ass

1 2 30.0%

0.5%

1.0%

1.5%

2.0%

2.5%

3.0%

3.5%

2.0% 2.0% 2.0%

0.0%

0.5%

1.0%

Ecobond / Bitumen Dosage

Bitumen Emulsion Ecobond Polymer

Sample Number

Tota

l Dos

age

Ecobond 5050 Water resistance:

Road Applications

Upgrading gravel roads to surfaced

• Cold in-situ gravel road stabilization creating a durable reinforced base course, which is then surfaced.

• E.g. in-situ support >15%CBR, 125mm BSM2 (G6) and bituminous seal or asphalt (drainage?)

Road overlays:

Many existing roads that now

have insufficient

bearing capacity for their traffic

loads can be upgraded by adding a new

base & wearing course.

BSM 1 or 2G1

Cold Insitu Recycling:

Cement Recycling & Crushed Stone Overlay Method

BSM Recycling Method

Ecobond modified crushed stone for moisture & permanent deformation

resistance, cement stabilized sub base provides support.

Ecobond BSM for moisture & permanent deformation

resistance.

Suitable Construction Methods:

Road recyclers,

Conventional equipment,

Labour intensive methods

and in-plant mixing

Road Recycling:

Mechanical Road Construction:

Labour Based Road Construction:

Application Examples

Ecobond BSM2, Soshanguve- City of Tshwane

Road reconstruction – Ecobond BSM2

• ES1 traffic class• 25mm HMA• 100mm Ecobond BSM 2 Base

Course Stabilized G6• Built on G6 foundation

• Faster construction than importing crushed stone.

• Total cost was 30% less than other roads in area for the same design life

• Road to be used as drain• Previous conventional road is

being rebuilt after 2 years life span.

EBSM Base Course (before Asphalt)

Example: Municipal Gravel Road Modification & Spray OnLibanon Landfill, Westonaria Municipality

• Ecobond 15mm spray on• Ecobond 150mm Modification

Ecobond Sprayed onto modified gravel roads.

Garbage/dump trucks

Shear strength of gravel road increased

Abrasion and erosion control with spray on.

(Please see Modify and

SprayOn Doc)

Example: Ecobond labour intensive road shoulders

Ecobond Wearing course, Centurion, City of Tshwane, EPWP

• Ecobond 30mm wearing course (can be thicker)

Stabilized road shoulders reduce erosion and edge

breaks/road narrowing.

Keep sub-layers drier, increasing pavement life.

Ecobond 5050 Base Course:

Pinetown/Ethikwini

Example: Ecobond 5050 in-situ upgrade• 25mm Asphalt• 125mm Ecobond 5050 C3 Base Course Stabilized in-

situ• Road recycling, conventional equipment• Previous highly cemented Base Course failed• Water in subgrade (hills).

Ecobond Road Eikenhof

Example: Using the aggregate in the project area• Perpetual pavement concept

• Category D – ES1• 6.7mm Slurry• 125mm Ecobond BSM 1 Base

Course Stabilized G2• Built on 2 lime treated sub

bases

• Next to crushed stone plant.• Poor drainage• Clay active in subgrade• Lime modified aggregate

reduces clay activity and provides support

• Ecobond BSM1 increases wet strength and remains flexible

Low Volume road Example: Modikwe Road, North West

Example: Ecobond 5050 partially bound base course Ecobond Base course, Modikwe, North West

• Built in 2005• Ecobond 100mm base • Surface seal

Category D RoadES1

Base course 100mm borrow

pit G6

Built on existing gravel road.

Ecobond 5050 Mini Base Course: Parys, Free State

Example: very low volume road upgrade• Objective, reduce gravel road

maintenance and create employment

• Houses are built, traffic volumes not likely to increase.

• 25mm Cold Asphalt• 75mm Ecobond 5050 Base

Course Stabilized in situ• Built on existing gravel road

• Lane in between 2 roads.• Road is drain• Base to provide some water

resistant support for surfacing• Residents used to construct cold

asphalt surfacing

Example: Ecobond Wearing CourseEcobond Wearing course, Chintsa, East Cape

• 2,5% Ecobond 150mm Stabilized G5

Low volume road, no maintenance or re-gravelling

since 2007.

Laboratory testing can

involve UCS (4hr soak), abrasion

and erosion testing.

Example: Ecobond Wearing CourseEcobond Wearing course, Rabie Ridge, JRA

• Ecobond 100mm Wearing Course

Stabilized road surface reduces

erosion and abrasion.

Keep sub-layers drier, increasing pavement life.

No mud and no re-gravelling after

1 & 1/2 years.

Example: Spray OnEcobond Spray On, Piggs Peak, Swaziland

• Ecobond 30mm Spray OnEcobond Sprayed

onto existing gravel roads.

Low traffic volumes, but

significant environmental

erosion.

No re-gravelling after 5 years.

Typically tested through water erosion tests.

Ecobond Aggregate Modification – Majuba Power StationFailed provincial Road

Example: Temporary Modification• 3 month design life• 1100 superlinks per lane per

day• 0.3% Ecobond Modification &

0.5% Ecobond Modification• 100mm Ecobond Temporary

Wearing Course In Situ recycled• Failed provincial road

• Road could not be closed• Heavy Rainfall in Nov 2010

during construction and traffic• 0.3% sections did not achieve

design life (1 month) – Approx. 0.165 MESA.

• 0.5% sections exceeded design life (6 months). Approx 1 MESA.

Ecobond Road Design Example: Duvha Road, Witbank, Mpumalanga

Example: Ecobond Durability

Ecobond Base course, Duvha, Witbank• 2% Ecobond 100mm base • 650mm of gravel support layers • 6.7mm bitumen slurry seal• A new 13,2mm single seal was

added in the 10th year.

It is in good condition after more than 30 million E80kN axle loads over 16 years.

The adjacent conventional road had many potholes in 2010/11 compared to none in the Ecobond Section.

• BSM:

• Road Recycling in JHB

• Road Recycling Gauteng Province

• 5050:

• Base courses in South Africa, Australia, Hungary, Zambia, Namibia and Swaziland

• Wearing Courses:

• Western Cape Province, Mines and Game Farms

• Spray Ons:

• Various Mines including Anglo American and Exxaro

• Modification

• Selected layers in cuttings for increased shear strength, water resistance and to allow good density, Eastern Cape Province

• Many others, please contact us for details.

• Ecobond products are currently specified in over 200km of roads projects.

Brief Ecobond products examples:

More than 3000 laboratory tests and field applications since 1996 have proven conclusively that Ecobond works.These tests were done at:

• The University of Pretoria• CSIR• SABS• Concrete Institute• Accredited Laboratories

Ecobond Works

Ecobond has been Certified by the PLC for Quality Control and Innovation in Building (EMI RT) in Hungary meeting and exceeding EU Standards.

Both EMI and Agremént are members of the WFTAO (World Federation of Technical Assessment Organizations).

Conclusion:• Bitumen emulsion is a well known material which is considerably

reinforced when Ecobond resin is added.

• This effective binder can be used in conjunction with other conventional materials to make pavement structures more durable and cost effective.

• This can help to create better infrastructure, which are both of great importance to governments, industry and their people.

Reinforced bitumen emulsion

Thanks.

Strong Water Resistant Soil

Cold Milled Asphalt Recycling:• Reclaimed old asphalt cold in plant mixed with 33% new

aggregate and 3% Ecobond 5050 creating a durable reinforced base course, paver laid on existing road. Surfaced with micro-surfacing or thin Asphalt

• Certified by EMI (WFTAO).• Up to 8 times less carbon emissions than standard

methods.• Can be one third the cost of traditional European

methods.

Surfacing can be applied usingmechanical

or labour intensivemethods

Labour based seal construction:

Ecobond & Cape Seal:

Ecobond & Cold Asphalt:

Ecobond Road Maintenance:

Ecobond Road Maintenance:

Strong, Water Resistant Ecobond soil can store water.

Ecobond Elephant pond,

Savuti, Botswana:

Under water since 1996.

Loskop Ecobond Pond

20,000m2 Ecobond

Water Storage

Dam

Loskop Ecobond Garden Canal

How to utilize Ecobond water storage:

People can: •Harvest the rain water, for livestock or irrigation

•Build Fish Farms

•Use an underground layer of Ecobond to save water and protect against rising salts for agriculture in arid areas.

Some Ecological Aspects of Ecobond

Green:• Biodegradable resin.• Doesn’t bio accumulate.

Carbon:• Direct reduction on carbon emissions

compared to conventional materials.• Less production time and material haulage

means less energy spent on construction.

• Housing• Footpaths• Erosion control• Pothole Fix• Cable trench

protection• Fence Post Anchoring• Waste Containment

and dust prevention• Athletics tracks &

Sports Fields• Many other

applications.

Many more applications:

3.30% 3.45% 3.60% 3.80%0.00%

1.00%

2.00%

3.00%

4.00%

5.00%

3.30% 3.30% 3.30% 3.30%

0.00% 0.15% 0.30% 0.50%

Ecobond to Bitumen Ratio

Bitumen Emulsion

Ecobond Polymer

Test Sample

Tota

l Dos

age

by S

oil M

ass

0% 0.15% 0.30% 0.50%0

500

1000

1500

2000

2500

3000

3500

4000

4500

2100

2500

3400

4000

UCS Strength Results

Added Ecobond Polymer Dosage

UC

S (

kPa)

Ecobond Reinforced Bitumen Emulsion: