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A TECHINACAL PAPER ON GREEN CONCRETE
New Technology In Concrete
CONTENTS
INTRODUCTION
GREEN LIGHTWEIGHT AGGREGATES
GREEN CEMENT WITH REDUCED ENV. IMPACT
PRODUCTION OF GREEN CONCRETE
SUITABILITY OF GREEN CONCRETE IN STRUCTURES
ADVANTAGES
APPLICATION OF GREEN CONCRETE
LIMITATIONS
SCOPE IN INDIA
CONCLUSION
REFERRANCES
INTRODUCTION
The concrete is made with concrete wastes which is eco-friendly so called as Green concrete.
The other name for green concrete is resource saving structures with reduced environmental impact for e.g. Energy saving ,co2 emissions, waste water.
Green concrete is a revolutionary topic in the history of concrete industry. This was first invented in Denmark in the year 1998 by Dr.WG.
GREEN CEMENT WITH REDUCED ENV. IMPACT
The cement is based on an intermediate product, clinker, which is produced with minor additions of mineralizes (CaSO4 and CaF2) to the kiln resulting in 5% reduction in energy consumption and 5-10% increase in 28-day strength of the cement.
cement with reduced environmental impact. (mineralized cement, limestone addition, waste-derived fuels).
By replacing cement with fly ash, micro silica in larger amounts.
PRODUCTION OF GREEN CONCRETE
Concrete with inorganic residual products (stone dust, crushed concrete as aggregate.)
ceramic wastes used as green aggregates.
By replacing cement with fly ash, micro silica in larger amounts.
To develop new green cements and binding materials (i.e. by increasing the use of alternative raw materials and alternative fuels, and by developing/improving cement with low energy consumption).
To use residual products from the concrete industry, i.e. stone dust (from crushing of aggregate) and concrete slurry (from washing of mixers and other equipment).
To use new types of cement with reduced environmental impact. (mineralized cement, limestone addition, waste-derived fuels).
Green lightweight aggregates
Synthetic lightweight aggregate produced from environmental waste is a viable new source of structural aggregate material.
The uses of structural grade lightweight concrete reduce considerably the self-load of a structure and permit larger precast units to be handled.
Water absorption of the green aggregate is large but the crushing strength of the resulting concrete can be high.
The 28-day cube compressive strength of the resulting lightweight aggregate concrete with density of 1590 kg/m3 and respective strength of 34 MPa.Most of normal weight aggregate of normal weight concrete is natural stone such as limestone and granite.
SUITABILITY OF GREEN CONCRETE IN STRUCTURES
Reduce the dead weight of a facade from
5 tons to about 3.5 tons.
Reduce crane age load, allow handling,
lifting flexibility with lighter weight.
Good thermal and fire resistance, sound
insulation than the traditional granite rock.
Improve damping resistance of building.
speed of construction, shorten overall construction period.
ADVANTAGES
Reduction of the concrete industry's CO2-emmision by 30 %.
Increased concrete industry's use of waste products by 20%.
NO environmental pollution and sustainable development.
Green concrete requires less maintenance and repairs.
Green concrete having better workability than conventional concrete.
Good thermal resistant and fire resistant.
Compressive strength behaviour of ceracrete with water cement ratio is similar to conventional concrete.
Flexural strength of green concrete is almost equal to that of conventional concrete.
LIMITATION
By using stainless steel, cost of reinforcement increases.
Structures constructed with green concrete have comparatively less life than structures with conventional concrete.
Split tension of green concrete is less than that of conventional concrete.
SCOPE IN INDIA
Green concrete is a revolutionary topic in the history of concrete industry.
As green concrete is made with concrete wastes it does take more time to come in India because industries having problem to dispose wastes.
Also having reduced environmental impact with reduction in CO2 emission.
CONCLUSION
Green concrete having reduced environmental impact with reduction of the concrete industries co2 “emissions by 30%.
Green concrete is having good thermal and fire resistant.
In this concrete recycling use of waste material such as ceramic wastes, aggregates, so increased concrete industryâ„¢s use of waste products by 20% . hence green concrete consumes less energy and becomes economical.
So definitely use of concrete product like green concrete in future will not only reduce the emission of co2 in environment and environmental impact but also economical to produce.
REFERRNCES
Indian concrete journal volume 77 -January -2003-N0.-1 Green concrete technology by R.M. Swamy on page no. 878
Green concrete using industrial wastes. Proceedings, National conferences on advances in building materials. Vellore Institutes of technology, Vellore.
Devdas Manoharan.p.Senthamarai.R.M. Concrete using ceramic insulators scraps as coarse aggregates. Proceedings, 6th International conferences on conc. Tech, Amman, Jordan.
Galvind, Munch-Petersen, Green concrete structural concrete.
Websites:
http://greenconcrete.dk/
http://diamondbidewarehousegreen concrete.html.
