Concrete pavements : sustainability through durability · Concrete pavements : sustainability through durability André Jasienski Managing director FEBELCEM. FICEM –Forum of Institutes

FICEM – Forum of Institutes 12 October 2010

Concrete pavements :

sustainability through durability

André Jasienski

Managing director FEBELCEM


Sustainable construction


Sustainability - Durability

UK : Sustainability Sustainable development

Durability Pavement durability

FR : Durabilité Développement durable

Durabilité Durabilité du revêtement

NL : Duurzaamheid Duurzame ontwikkeling

Duurzaamheid Duurzaamheid van de verharding

D : Nachhaltigkeit Nachhaltige Entwicklung

Dauerhaftigkeit Dauerhaftigkeit von die Stra e

ES : Sostenibilidad Desarollo sostenible

Durabilidad Durabilidad del pavimento


Importance of life-cycle approach

LCA is a method to evaluate the overall environmental impact of a (functional) unit (e.g. 1 m² pavement, 1 km motorway) over the entire life-cycle “from cradle to grave”, following standardized procedures (ISO 14040, ISO 14044).


Carbon Footprint

The Carbon Footprint is the overall amount ofcarbon dioxide (CO2) and other greenhousegas emissions (methane, nitrous oxide,fluorinated gases) associated with a productalong its supply chain, including use and end-of-life recovery and disposal.

= part of a more complete approach (LCA)

If only greenhouse gases were to be considered, this could have a negative effect on other environmental aspects.


Environmental indicators

Indicator Unit

Primary energy MJ

Water Consumption kg

Natural Resources 10-9 (consumption compared to world reserves)

Wastes t eq

Radioactive wastes dm³

GWP100 (greenhouse gases) kg CO2

Acidification kg SO2

Eutrophication kg PO43-

Ecotoxicity m³ eq. polluted water

Toxicity to humans kg eq. contaminated flesh

O3 smog kg eq. C2H2

Odour m³ eq. air pollution due to ammonia


Cement production and CO2

1 ton cement 1 ton CO2

1 ton cement 750 kg CO2 (EU average)


Cement production and CO2


Embodied energy

Material

Embodied energy

MJ/kg MJ/m³

Concrete 30 MPa -CEM I 1,3 3180

Concrete 40 MPa -CEM I 1,6 3890

Asphalt 3,4 7140

Brick 2,5 5170

Timberwood 2,5 1380


LCA – French study on road structures

Study by the “Centre d’Energétique de l’Ecole des Mines de Paris”

Functional unity = 1 km motorway with 2 x (2 lanes + emergency lane)

Lifetime of 30 years, 100 million vehicles, 25 million heavy goods vehicles

Data from Ecole Polytechnique from Zurich (Oekoinventaire) and the University of Karlsruhe (Oekoinstituut Weimar)

Comparison of :

• 4 structures in concrete (plain concrete = slabs, reinforced concrete, different base-layers)

• 1 composite structure (thin bituminous wearing course on continously reinforced concrete)

• 1 asphaltstructure


Lifetime impact of a road – not including traffic

Comparison plain concrete, reinforced concrete

and asphalt

0,00E+00 1,00E+00 2,00E+00 3,00E+00 4,00E+00 5,00E+00 6,00E+00 7,00E+00

Primary energy (10E+01

TeraJoules)

Water consumption (10E+07 kg)

Natural resources (10E-08)

Wastes (10E+04 t eq)

Radioactif wastes (10E+02 dm³)

GWP100 - greenhouse gases

(10E+06 kg CO2)

Acidification (10E+04 kg SO2)

Eutrophication (10E+03 kg

phosphate ions)

Ecotoxicity (10E+08 m³)

Toxicity to humans

O3-smog (10E+04 kg)

Odour (10E+09 m³)

Jointed plain concrete

CRCP

Asphalt


Lifetime impact of a plain concrete road –

including traffic

0,00E+00 2,00E+01 4,00E+01 6,00E+01 8,00E+01 1,00E+02 1,20E+02 1,40E+02 1,60E+02

Primary energy (10E+01 TeraJoules)

Water consumption (10E+07 kg)

Natural resources (10E-08)

Wastes (10E+04 t eq)

Radioactif wastes (10E+02 dm³)

GWP100 - greenhouse gases (10E+06

kg CO2)

Acidification (10E+04 kg SO2)

Eutrophication (10E+03 kg phosphate

ions)

Ecotoxicity (10E+08 m³)

Toxicity to humans

O3-smog (10E+04 kg)

Odour (10E+09 m³)Construction, maintenance and end-of-life phasesUsage phase (traffic)


Fuel savings

A series of four researches by the National Research Council of Canada on

the fuel consumption on asphalt, concrete and composite pavements.

Conclusions of the last phase of the research :

Fuel savings on concrete roads, compared to asphalt roads,

Both for an empty and full tractor-trailer unit,

Ranged from 0,8 to 3,9 %

With statistically significant results

with a reliability of 95 %.

An average fuel saving of 2,35 % allows to compensate the

complete CO2 from cement production in 20 to 30 years lifetime


Recycling

Concrete can be 100 % recycled

Sub-bases

Base layers (unbound and cement bound aggregate mixtures, lean concrete, roller compacted concrete)


Recycling

Recycling concrete rubble in pavement quality concrete is perfectly feasible when used as twin course concrete

Up to 60 % in the bottom layer

Example : worksite N49 Zwijndrecht

: first Belgian application of twin

course CRCP with recycled

aggregates in the lower course


Economic aspects

Minimal maintenance over the longest possible lifetime


Economic aspects

Comparison of lifecycle cost (construction + maintenance) for motorways in concrete and asphalt

COMPARISON OF PAVEMENT COST

700000

900000

1100000

1300000

1500000

1700000

1900000

2100000

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Years

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ST

S I

N

EU

RO

S Year

CRC Case 1

CRC Case 2

CRC Case 3

CRC Case 4

Bitum. Case 5

Bitum. case 6

Discount rate 2,6 %


Economic aspects : price stability

+ importance of local materials (cement vs. bitumen)

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Bitumen Heating oil Cement


Societal and social benefits

Safety for the road users

- skid resistance

- visibility

- absence of rutting

- no danger of aquaplaning


Societal and social benefits

Ride comfort for the road users

- evenness

- rolling noise


Durability through quality

“Long-life pavements” are essential in LCA (environment) and LCCA (economy) and can only be achieved through

QUALITY

- Materials

- Concrete mix (cement, W/C, sand, air)

- Design

- Construction

- Maintenance

“Quality” will be one of the key drivers in the future structure and working of EUPAVE


Conclusions

- Performance in each of the three fields of sustainable construction :

- Environment

- Economy

- Social and societal importance

- Improvement is still possible through research and study

- No short term gains which might compromize the long term behaviour

Choosing a concrete road is choosing a durable and

sustainable solution


Thank you for your kind attention

Documents

Concrete pavements : sustainability through durability · Concrete pavements : sustainability through durability André Jasienski Managing director FEBELCEM. FICEM –Forum of Institutes