Presented by:

Haider Ali JafferiM.Ali Rehman Siddiqui

ECO-FRIENDLY CONCRETE

GREEN CONCRETE

Presentation Overview What is Eco-Friendly Concrete? Set-backs of Traditional Concrete Where Does CO2 come from in Concrete? Need of Eco-friendly Concrete Features of Eco-Friendly Concrete Strategies for Eco-Friendly Concrete Materials for Eco-Friendly Concrete Green Concrete Mix Design Objectives Sustainable/Green Construction with Green Concrete Advantages of Eco-friendly Concrete Conclusions

What Is Eco-Friendly Concrete Concrete that uses less energy in its production & produces

less carbon dioxide than normal concrete is referred to as Eco-friendly or Green Concrete.

Environment friendly. Considered to be cheap to produce. Less energy consumption & greater durability.

Set-Back of Traditional Concrete Traditional concrete is made from a mixture of cement, sand,

gravel and water. Cement is an environmentally hazardous material for the

following reasons: Cement production is extremely energy intensive, making it third

producer of CO2 emission. Cement production is increasing approximately 5% a year, making

it one of the most environmental destructive material. Aggregate materials like sand and stone that are mixed with

cement are mined from quarries, further taxing our natural resources.

Where Does CO2 Come From In Concrete Two main sources:i. Cement: Most of CO2 in concrete is from the cement

manufacturing process. A typical cubic meter of concrete contains about 10% cement by weight. The reaction in the process of Cement manufacture is:

ii. Aggregates: Use of virgin aggregates contributes about 1% of all CO2 emissions from a typical cubic meter of concrete. Therefore, the use of alternate aggregate is desirable. The use of local and recycled aggregates is desirable as it can reduce transportation and fuel cost and support sustainable development.

CaCO3 = CaO + CO2

Need Of Eco-Friendly Concrete Need of green concrete for better environment and

sustainable construction can be characterized by the following factors;

Consumption of Natural Resources: More than 5 cubic billion yard concrete is produced globally, requiring huge natural resources for producing cement and aggregates.

Global Warming: One ton of cement releases one ton of CO2 into the atmosphere (greenhouse gas) contributes to the global warming.

Water Consumption: Concrete industry uses over one trillion gallon of water each year globally.

Features Of Eco-Friendly Concrete The concrete which can fall in the category of Eco-friendly

must have the following characteristics. Optimize use of available materials Better Performance Enhanced cohesion workability / consistency Reduced shrinkage / creep Durability - Better service life of concrete Reduced carbon footprint No increase in cost LEED Certification

Strategies For Eco-Friendly ConcreteThe number of strategies, whereby Eco-friendly concrete can

help in achieving the sustainable construction are: Increased dependence on recycled materials. Effective use of supplementary cementitious materials. Improved mechanical properties. Reuse of wash water.

Materials Selection Criteria Green construction materials are composed of renewable,

rather than non renewable resources. Green materials are environmentally responsible because impacts are considered over the life of the product. Depending upon project-specific goals, green materials may involve an evaluation of one or more of the following criteria. Locally available Salvaged, re-furnished or re-manufactured Reusable or recyclable Resource & Energy efficiency Indoor air quality (IAQ) Water conservation

Materials For Eco-Friendly Concrete Cement Replacements:

GGBS Fly Ash

Recycled Glass Silica Fume

Materials For Eco-Friendly Concrete Aggregates Replacement:

Recycled Concrete Material Waste Plastic

Demolition Waste Recycled Glass Aggregates

Materials For Eco-Friendly Concrete

1.Cement Replacement

The reduction in the use of Portland cement can be achieved with partial replacement of cement by the various cementitious materials, such as: Fly Ash Ground Granulated Blast Furnace Slag Silica Fume Wood Ash etc.

Materials For Eco-Friendly ConcreteA. FLY-ASH: Fly-ash usually refers to the ash produced during the combustion of coal. Less expensive than OPC and improves the strength of concrete. Generates less heat of hydration, thus preferable for mass concrete

applications. Fly ash use in concrete improves the workability of plastic concrete, and the

strength and durability of hardened concrete.

Materials For Eco-Friendly ConcreteAdvantages of Fly-Ash: Utilization of fly ash as a part replacement of cement or as a mineral

admixture in concrete saves on cement and hence the emission of CO2. Use of good quality fly ash in concrete has shown remarkable

improvement in durability of concrete, especially in aggressive environment.

Some of the technical benefits of the use of fly ash in Green Concrete are: Higher ultimate strength  Increased durability  Improved workability  Reduced bleeding  Increased resistance to alkali-silica reactivity. Reduced shrinkage.

Materials For Eco-Friendly ConcreteB. GROUND GRANUALTED BLAST-FURNACE SLAG: Excellent cementitious material. Obtained by quenching of molten iron slag form blast furnace into

water/steam, to produce glassy granular product, dried and grounded to fine powder.

Optimum cement replacement level is about 70 to 80 %. Produces less heat of hydration and improves the durability of

concrete.

Materials For Eco-Friendly ConcreteComparison of GGBFS with Portland Cement Concrete: Concretes with higher dosages of GGBFS will have lower heat of

hydration. Concerts containing slag may show longer time of setting than

PCC for moderate and higher dosages and at lower ambient temperatures.

Concrete with GGBFS gains strength more slowly, will have lower strength at early ages and equal or higher strength at later ages.

Increasing slag dosage is associated with lower permeability in concrete.

Concrete containing GGBFS dosage greater than 35% by mass of cementitious material, have shown improvement in resistance to sulphate attack as well as to alakli-aggregate expansion.

Materials For Eco-Friendly Concretec. SILICA FUMES: Also known as “micro silica” Ultra fine powder obtained as a by-product of silicon

and ferrosilicon alloy production, from the condensation of Silicon dioxide gas.

Consists of spherical particles of 150nm dia. Silica fume is typically used in quantities ranging

from 7 to 12% of the mass of the cementitious material

Improves the durability and increases the ultimate compressive strength.

Materials For Eco-Friendly ConcreteAdvantages of using Silica Fume (SF) It is generally specified for specialized applications such as

structures exposed to aggressive chemicals. It increases durability by making concrete less permeable.

Increase compressive strength as well. Due to its smaller size it decreases the void space in the

cement matrix, phenomenon is known as packing. Properly proportioned silica fume concrete can achieve very

high early and ultimate compressive strength.

Materials For Eco-Friendly ConcreteD. WOOD ASH: Wood ash is the residue powder left after the combustion of

wood. Wood ash has a huge capability for use as mineral admixture

and activator in cementitious material. Improves the compressive strength, appropriate for the many

structural application.

Materials For Eco-Friendly Concrete

2. Aggregate ReplacementGreen concrete can be produced by the use of recycled material, few of these are as follows: Concrete Debris Post Consumer Glass Foundry Sand Waste Plastic Stone Crusher Wastes

Materials For Eco-Friendly ConcreteA. CONCRETE DEBRIS: Most important replacement for reuse as aggregate in new

concrete. Use of concrete debris to produce new concrete conserves

natural resources, reduces valuable landfill capacity and reducing the use of virgin material.

Materials For Eco-Friendly ConcreteB. POST CONSUMER GLASS: Glass is a unique inert material that could be recycled many

times without changing its chemical properties. Suitable aggregate for the concrete. Substantially reduces consumer landfill waste. Increases the durability of concrete.

Waste Glass ConcreteRecycled Glass Aggregates

Materials For Eco-Friendly Concretec. FOUNDARY SAND: Commonly known as metal casting sand having high quality

silica sand. Sand is typically recycled and reused through many production

cycles. Foundry sand full fills the ASTM requirements for compressive

strength, absorption, and bulk density.

Materials For Eco-Friendly ConcreteD. WASTE PLASTIC Plastic is cheap, flexible and strong material and can be

recycled to produce many new products. Industrial wastes from poly-ethylene-terephthalate (PET)

plastic waste were studied as the alternative replacement of a part of the conventional aggregates.

5 to 50 % replacement levels may be used. The modified concrete mix, with addition of plastic aggregate

replacing conventional aggregate up to certain 20% gives strength with in permissible limit.

Waste Plastic Waste Plastic Concrete

Materials For Eco-Friendly ConcreteE. STONE CRUSHER WASTES: Quarry Rock Dust can be defined as residue, after the

extraction and processing of rocks to form fine particles. It can be used as an alternative replacement for sand in the

concrete. It has sharp and angular particles, thus because of such

causes a gain in strength due to better interlocking. Quarry rock dust concrete experiences better sulfate and

acid resistance. Its permeability is less as compared to that of conventional

concrete.

Stone Crusher Wastes Waste Stones for Green Conc.

Green Concrete Mix Design Objectives The concrete mix design method for green concrete is same as the

traditional concrete. The basic Green concrete mix design objectives are:

Optimizes void spaces between aggregates by optimizing particle proportion and packing materials.

Aggregates replace excess cement paste to give improved stability, less shrinkage and increase in strength & durability.

Less cement also generates less heat of hydration. The slump of the concrete and its flow are a function of the shape &

the quantity of the predominant size of the aggregate in the mix. Use of more fine aggregate gives higher slump & flow. So the optimum

proportions of coarse & fine aggregate must be critically found to have the best and dense concrete in both fresh & hardened stage of concrete.

Sustainable/Green Construction with Green Concrete Green building (also known as green construction or sustainable

building) refers to both a structure and the using of processes that are environmentally responsible and resource-efficient throughout a building's life-cycle: from siting to design, construction, operation, maintenance, renovation, and demolition.

Green Constructions which are concerned with the minimizing of environmental impact, while optimizing its economical capability.

Green construction is focused on: Affordability & Durability Efficiently using energy, water, and other resources Protecting occupant health and improving employee productivity Reducing waste, pollution and environmental degradation Effectiveness

Advantages of Green Concrete The main environmental benefits of Green concrete are:

Reduction of CO2 emission by concrete upto 30 %. Increases the use of waste products upto 20% by concrete industry, thus

reducing waste disposal problems. Other advantages may include:

Reduce the dead weight of a structure and allows easy handling, lifting flexibility with lighter weight.

Speeds up construction, and shorten overall construction period. Less maintenance & repair required. Economical than traditional concrete. Green Concrete uses local and recycled materials in concrete. The heat of hydration of green concrete is significantly lower than traditional concrete. This result in a lower temperature rise in large concrete pours which is a distinct

advantage for green concrete.

Advantages of Green Concrete Improved engineered properties of green concrete may

include: Mix can result in a reduced paste volume within the concrete

structure resulting in a higher level of protection against concrete deterioration.

Higher strength per kilogram of cement. Increased durability & lower permeability. More aggregates typically mean higher Modulus of elasticity.

Conclusion Green concrete technology is one of the major steps that a

construction industry can implement to achieve sustainable construction with various means as discussed above.

Green concrete Technology can save the natural materials for future use or the generations to come and sustain it for good amount of time.

By using waste materials for construction, the virgin materials will become a sustainable material and as well the cost will be reduced.

The usage of green concrete ensures sustainable development and it is gaining popularity ever since its initiation.