The concrete is made with concrete wastes which are eco-friendly so called as Green concrete. Most people associate GREEN concrete with concrete that is colored with pigment. However, it is also referred which has not yet hardened. But in the context of this topic, green concrete is taken to mean environmentally friendly concrete. This means concrete that uses less energy in its production & produces less carbon dioxide than normal concrete is green concrete.

Engineers and architects have choices of the material and products they use to design projects - when it comes to a building frame the choice is typically between concrete, steel and wood. Material choice depends on several factors including first cost, life cycle cost and performance for a specific application. Due to growing interest in sustainable development, engineers and architects are motivated more than ever before to choose materials that are more sustainable. However, such choice is not as straight forward as selecting an energy star rated appliance or a vehicle providing high fuel mileage.

Engineers and architects can compare materials and choose one that is more sustainable or specify a construction material in such a way as to minimize environmental impact? Recent focus on climate change and the impact of greenhouse gas emissions on our environment has caused many to focus on CO2 emissions as the most critical environmental impact indicator.

Life Cycle Assessment (LCA) is the parameter; the construction industry should look into. LCA considers materials over the course of their entire life cycle including material extraction, manufacturing, construction, operations, and finally reuse/recycling.

Concrete is one of the world's most widely used structural construction material. High quality concrete that meets specification requires a new standard of process control and materials optimization. Increasingly, concrete is being recognized for its strong environmental benefits in support of creative and effective sustainable development. Concrete has substantial sustainability benefits.

The main ingredient in concrete is cement and it consists of Limestone (Calcium Carbonate CaCO3). During manufacture of cement, its ingredients are heated to about 800 - 10000C. During this process the Carbon Dioxide is driven off. Approximately 1kg of cement releases about 900gms of Carbon Dioxide into the atmosphere.

Why Green Concrete?

• Huge impact on sustainability
• Most widely used material on Earth
  • 30% of all materials flows on the planet
• 70% of all materials flows in the built environment.
  • > 2.1 billion tonnes per annum.
  • >15 billion tonnes poured each year.
  • Over 2 tonnes per person per annum.