recycled asphalt pavement presentation slide

5/19/2018 Recycled Asphalt Pavement Presentation Slide

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GROUPS PRESENTATION

FINAL PROJECT


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Problem Faced The Alternative Material

Concept of Sustainability

Definition of Bitumen and RecycledPavement

The Introduction of RECYCLED PAVEMENT

Properties of RECYCLED PAVEMENT

The Process Involved

The Advantages and Disadvantages ofRP

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Bitumen manufacture causes environmental impacts at

all stages of the process.

Bitumen manufacturing releases Carbon dioxide, water

and smaller amount of Carbon Monoxide in the

atmosphere.

All hydrocarbons give off fumes when they are heated

and all hydrocarbon fumes are potentially damaging to

the environment.

It will burn fiercely if its temperature raised sufficiently. Odour from fumes is probably the major problem

associated with bitumen use which the residents living

near the boundary of plant and factory can smell the

fumes.

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The alternative materials that have potential

to replace the bitumen is Recycled

Pavement/Recycled Asphalt Pavement

(RAP)

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BITUMENRECYCLEDPAVEMENT

ALTERNATIVE MATERIAL


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The concept of sustainability is a wide approach in aperiod when environmental problems caused byvarious human activities are requiring serioussolutions.

In this context, Sustainable roadway construction canbe defined as the optimal use of natural and man-made resources during the roadway lifecyclecausing negligible damage to the environment.

Two means of improving the sustainability of

roadways are to minimize the amount of energyconsumed for their construction and to efficiently useroadway materials to reduce waste.

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Sustainable construction aims atreducing the environmental impact of a

building over its entire lifetime,whileoptimizing its economic viability and thecomfort and safety of its occupants.

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Recycled pavement inherently contributes tosustainability in many respects, and in others thesetools are helping the industry set goals to fosterimprovements towards a sustainable society.

To date most sustainability or green voluntarycertification programs attempting to qualitysustainable materials have focused primarily oni)energy

ii)material and

iii)water conservation iv)indoor environmental quality v)and site selection and development. Each of these is an important aspect of sustainable

building design and road construction.

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Bitumen is a naturally occurring mixtureof polycyclic

aromatichydrocarbons.

The mixture takes the form of a viscous black sticky tar-

like substance.

It can be refined from crude oil by fractional distillation.

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oThe primary use of asphalt/bitumen is

in road construction where it is with

aggregate. The other main uses for

sealing flat roofs.

o Also called Asphalt
http://en.wikipedia.org/wiki/Construction_aggregatehttp://en.wikipedia.org/wiki/Construction_aggregate


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Reprocessed pavement materials containing

asphalt and aggregates.

These materials are generated when asphalt

pavements are removed for :

-Reconstruction

-Resurfacing

-To obtain access to buried utilities.

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The same material can be recycled again andagain, it never loses its value.

While reclaimed asphalt pavement (RAP) is the

material most often used in asphalt recycling,materials from other industries are routinelyrecycled into asphalt pavements instead ofgoing into landfills.

Asphalt plants also recycle the fine mineral

particles that are generated in the process ofproducing asphalt pavement material. This routine recycling of co-generated material

helps to conserve natural resources.

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Why Need ToReplace Existing

Material?

Help inconservation

of naturalresources

Maintainpavement

geometrics aswell as pavement

thickness

Reducespollution

Substantialsavings over

the use of newmaterials


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Recycling or reuse of pavement material is a very simple but powerful concept.

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In some cases traffic disruption is less than that for other rehabilitation

techniques

It also helps to solve disposal problems because of the reuse of existing

material pavement geometrics and thickness can also be maintained during

construction.

Recycling of existing pavement to produce new pavement materials is

considerable savings of material money and energy.


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Physical Properties

Mechanical Properties

Chemical Properties

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Type of Property RAP Property Typical Range of Values

Physical Properties Unit Weight1940 - 2300 kg/m 3 (120-140 lb/ft

3)

Moisture Content Normal : up to 5%Maximum: 7-8%

Asphalt Content Normal : 4.5-6% Maximum Range: 3-7%

Asphalt Penetration Normal : 10-80 at 25C (77F)

Absolute Viscosity or

Recovered Asphalt

Cement

Normal : 4,000 - 25,000 poises at 60C

(140F)

Mechanical Properties Compacted Unit Weight1600 - 2000 kg/m 3 (100-125 lb/ft

3 )

California Bearing

Ratio (CBR)

100% RAP: 20-25% 40% RAP and 60%

Natural Aggregate: 150% or higher

20/5/2013DAC 10402 16Table 1:Physical and mechanical properties of reclaimed asphalt pavement (RAP)


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Mineral aggregates constitute the overwhelming majority (93 to 97percent by weight) of RAP.

Asphalt cement is made up of mainly high molecular weight aliphatichydrocarbon compounds, but also small concentrations of othermaterials such as sulphur,nitrogen and polycyclichydrocarbons(aromatic/naphthenic)

It is a combination of asphaltenes and maltenes (resins and oils).

Asphaltenes are more viscous than either resins or oils and play a majorrole in determining asphalt viscosity.

Oxidation of aged asphalt causes the oils to convert to resins and the

resins to convert to asphaltenes, resulting in age hardening and a higherviscosity binder.


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The following methods of roadway rehabilitation recycleold pavement into new 2 type of recyled:

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1.The pavement is removed by cold planing to a depth of 3 to 4 inches.

COLD IN-PLACE RECYCLED

6.

Caltrans has used cold in-place recycling in over 25 projects in California.

5.A 3-piece "train" may be used, consisting of a cold planing machine, a

screening,crushing,mixing unit, and conventional laydown and rolling equipment.

4.An asphalt emulsion or a recycling agent is added, then the material is

placed and compacted.

3.Aggregate may be added to modify RAP characteristics.

2.

The material is pulverized, sized, and mixed with an additive.

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Another process involved :

-Hot Mix--Remixing.

-Hot Mix--Repave.Hot Mix--Heater Scarification

-Full-Depth Reclamation.20/5/2013DAC 10402 19

Hot, In-Place Recycling:

1.The pavement is softened by heating and is scarified or hot

milled to a depth of 3/4 to 1-1/2 inches and mixed.

2.New hot mix material and/or a recycling agent isadded in a single pass of the machine.

3.A new wearing course may also be added with anadditional pass after compaction.

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ENVIRONMENTALBENEFIT

ENGINEERING BENEFITS

ECONOMIC BENEFITS


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Environmental Benefits: Air quality problems resulting from dust,

fumes, and smoke are minimized.

Reduces the amount of new oil byproductneeded

saves on construction material waste, asthe recycled material is not sent to alandfill.

Lessen the pollution and CO2 producedat each step of the process

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Economic Benefits

Cost is susceptible to fluctuating prices in

the market. Contractors save by reducing energy,

materials and waste-hauling costs.

Lower quality asphalt can be used as asubstitute for embankment, fill or roadbase material.

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ENGINEERING BENEFITS

Provide engineering benefits for

contractors and government agenciesinvolved in road maintenance

Save engineers and contractors time,money and materials

Allowing for more efficient roadmaintenance projects.

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Cold Temperature Performance

When in cold climates the use of recycled asphalt may contribute to the crackingof pavements.

The stiffness properties of the mix increase under these conditions.

Mix Guidelines

The current guidelines suggest a mix of 15 percent recycled asphalt paving. If higher amounts of mix are used, blending charts provide guidelines on the

amounts of recycled asphalt paving to use, depending on the grade of thebinder.

Variance in Quality

The quality of the paving can vary.

The quality of the recycled paving depends on factors such as the number of

times the source pavement had been resurfaced or had other work done on it. Sometimes debris and soil can get into the material while it is being stored for

recycling.

Thus, some measure of quality checking is necessary to see if the recycled pavingis suitable for its intended use.

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THANKYOU

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recycled asphalt pavement presentation slide

Documents

bitumen use

bitumen manufacture

sustainable construction

environmental problems

road construction

alternative materials

qualitysustainable materials

useroadway materials