The largest-volume of recycled material used as construction aggregate is blast furnace and steel furnace slag. Blast furnace slag is either air-cooled (slow cooling in the open) or granulated (formed by quenching molten slag in water to form sand-sized glass-like particles). If the granulated blast furnace slag accesses free lime during hydration, it develops strong hydraulic cementitious properties and can partly substitute for portland cement in concrete. Steel furnace slag is also air-cooled. In 2006, according to the USGS, air-cooled blast furnace slag sold or used in the U.S. was 7.3 million tonnes valued at $49 million, granulated blast furnace slag sold or used in the U.S. was 4.2 million tonnes valued at $318 million, and steel furnace slag sold or used in the U.S. was 8.7 million tonnes valued at $40 million. Air-cooled blast furnace slag sales in 2006 were for use in road bases and surfaces (41%), asphaltic concrete (13%), ready-mixed concrete (16%), and the balance for other uses. Granulated blast furnace slag sales in 2006 were for use in cementitious materials (94%), and the balance for other uses. Steel furnace slag sales in 2006 were for use in road bases and surfaces (51%), asphaltic concrete (12%), for fill (18%), and the balance for other uses

1. MEKAPATI RAJAMOHAN REDDY
INSTITUTE OF TECHNOLOGY& SCIENCE
PRESENTED BY
V.ASHOK KUMAR
14L41A0104
RECYCLED AGGREGATES

2. CONTENTS :
• INTRODUCTION
• WHAT ARE RECYCLED AGGREGATES
• WHY WE CHOOSE RECYCLED AGGREGATES
• SOURCES OF RECYCLED AGGREGATES
• PRODUCTION OF RECYCLED AGGREGATES
• COMPARISION OF RECYCLED AGGREGATES
AND NATURAL AGGREGATES
• MERITS AND DEMERITS OF RECYCLED
AGGREGATES
• APPLICATIONS OF RECYCLED AGGREGATES
• CONCLUSION

3. INTRODUCTION
 Recycling is the act of processing the used material
for use in creating new product.
 Usage of natural aggregate is becoming intense.
 Recycled aggregates can replace natural aggregate.
 Recycled aggregates are obtained from construction
and demolition debris.

4. What are Recycle aggregates
• Recycled aggregates are the aggregates produced
from the processing of previously used construction
materials such as concrete or masonry.
• Recycled aggregates consists of hard, graduated
fragments of inert mineral materials, including sand,
gravel, crushed stone, slag, rock dust, or powder.

5.  Due to rapid growth in population and urbanization, the
natural resources are depleting.
 High cost of good quality crushed aggregates, as
compared to Recycled aggregates.
 Shortage of dumping sites has resulted in sharp increase
in transport and disposal costs.
 An enormous increase in the quantity of waste materials
and the shortage of dumping sites.
WHY WE CHOOSE RECYCLED
AGGREGATES

6. SOURCES OF RECYCLED AGGREGATES
• Construction and demolished waste generated due to
natural disasters, for future development the old
buildings are replaced by new ones, and war
inflicted damages.
• Crushing of Portland concrete pavement
• Tested specimens from laboratory.
• Concrete from ready mix concrete plants and
precasting units.
• Worn out rail ballast.

7. PRODUCTION OF RECYCLED
AGGREGATES
RECYCLING PROCESS

8. Buildings and
pavements
BUIDING
DEMOLITION
Load and transport
to crushing plant
Crush/Size
Screening and
washing
Stockpile
Reuse

9. COMPARISION OF RECYCLED AGGREGATES AND
NATURAL AGGREGATES
NATURAL AGGREGATES RECYCLED AGGREGATES

12.  MERITS
 Light weight
 Minimum environmental impacts
 Saving in energy
 Job opportunities
 Sustainability
 Market is wide
MERITS AND DEMERITS OF RA

13. DEMERITS
 Strength is low
 Lack of suitable laws and guidelines
 Lack of specifications and standards
 Lack of experience
 Inefficient supply
 Lack of information

14.  Concrete kerb
Application of Recycled Aggregate as Road Kerb
APPLICATIONS OF RECYCLED
AGGREGATES

15.  PAVING BLOCKS
 Backfill material

16.  Recycling and reuse is an appropriate solution.
 Use of recycled aggregates prove to be valuable.
 There is a need for modifying codes, specification
 The subject of use of recycled aggregates in India
should be given importance
CONCLUSION

17. To Recycle
The Choice Is Yours…
To Landfill

19. 19