CHAPTER 01
INTRODUCTION
1.1 What is Green Concrete?
Green Concrete: The Concrete is made with concrete wastes which are eco-friendly so called
as green concrete. The other name for green concrete is resources saving structures with
reduced environmental impact for e.g. energy saving,co2emissions,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. sustainable development by the application of industrial waste to
reduce the consumption of natural resources and energy etc. Use of such materials saves
approximately 20% of cements. Thus, green concrete is an excellent substitute of cement as it
is cheaper, due to which it is made up of waste products, saving energy. Green Concrete has
greater strength & durability compared to normal concrete. Green concrete is a variation of
standard concrete that either uses recycled ingredients, uses ingredients that don’t harm the
environment, or lasts longer or performs better than traditional concrete, reducing the need for
replacement in the future.Sustainable concrete is an important innovation for a reason: standard
concrete production is responsible for 8% of carbon dioxide emissions worldwide.
Additionally, for every 2,055 lbs of cement manufactured, 2,044 lbs of carbon dioxide are
released into the atmosphere. Although materials like steel and wood actually produce more
carbon dioxide in production pound for pound, so much more concrete is produced every year
that it leaves these other materials in the shade. Concrete is actually the second most consumed
substance worldwide, with only water seeing more demand. As the graphs from Statista below
illustrate, global cement production has started to level off in recent years after reaching a little
over four billion tons annually. However, US production has continued to rise at a lower rate,
with nearly 90 million tons produced in 2020 (This is not the highest peak since 1995, however,
as the US reached 95 million tons in 2007). Green concrete is made using industrial waste
materials as a partial replacement for other concrete components, like cement or aggregate,
whose production takes a heavier toll on the environment. While some forms of green concrete
are newer, many may not realize that other types have been in use for decades. In this guide to
the different varieties of green concrete, we’ll take you through some of the most well-known
green concrete materials, old and new, as well as the properties they lend the finished product.
First, however, we’ll dig into precisely what green concrete is and how it differs from
traditional concrete.
1
, Fig 1.1.1 GREEN CONCRETE
1.2 Need of Green Concrete:
• The main ingredient in concrete is cement and consists of lime stone.
• During manufacture of cement its ingredients are heated to about 1450
1600^@C
• During this process Carbon Dioxide is released .
• Approximately 1 Kg of concrete releases about 900gms of carbon dioxide
in atmosphere.
Therefore, green concrete came into existence to reduce the emission of carbon dioxide.In
addition to the environmental goals there are a number of environmental intentions. Most
important are: To avoid the use of materials which contain substances on the Environmental
Protection Agency’s list of unwanted materials, not to reduce the recycling ability of green
concrete compared with conventional concrete and not to increase the content of hazardous
substances in the wastewater from concrete production compared with wastewater from
production of existing concrete types. Different concrete types are tested for workability,
changes in workability after 30 min., air-content, compressive strength development, E-
modulus, heat development, homogeneity, water separation, setting time, density and
pumpability. Furthermore, frost testing, chloride penetration and an air void analysis are carried
out for the concretes in the aggressive environmental class. The water/cement ratio,
water/binder ratio and the chloride content are calculated from the mixing report of the precise
mixture proportions and from the chloride content in the different raw materials.
2
, CHAPTER 02
STUDY OF GREEN CONCRETE
Fig 2.1 CO2 Emission 1970-2020
2.2 Materials for Green Concrete
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: Construction materials, components, and systems found locally or
regionally, saving energy and resources in transportation to the project site.
• Salvaged, re-furnished, or re-manufactured: Includes saving a material from disposal
and renovating, repairing, restoring, or generally improving the appearance,
performance, quality, functionality, or value of a product.
• Reusable or recyclable: Select materials that can be easily dismantled and reused or
recycled at the end of their useful life.
Recycled materials that the Industry has found to perform favourably as substitutes for
conventional materials include: fly ash, granulated blast furnace slag, recycled concrete,
demolition waste, micro silica, etc. Generation and use of recycled materials varies from place
to place and from time to time depending on the location and construction activity as well as
3
INTRODUCTION
1.1 What is Green Concrete?
Green Concrete: The Concrete is made with concrete wastes which are eco-friendly so called
as green concrete. The other name for green concrete is resources saving structures with
reduced environmental impact for e.g. energy saving,co2emissions,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. sustainable development by the application of industrial waste to
reduce the consumption of natural resources and energy etc. Use of such materials saves
approximately 20% of cements. Thus, green concrete is an excellent substitute of cement as it
is cheaper, due to which it is made up of waste products, saving energy. Green Concrete has
greater strength & durability compared to normal concrete. Green concrete is a variation of
standard concrete that either uses recycled ingredients, uses ingredients that don’t harm the
environment, or lasts longer or performs better than traditional concrete, reducing the need for
replacement in the future.Sustainable concrete is an important innovation for a reason: standard
concrete production is responsible for 8% of carbon dioxide emissions worldwide.
Additionally, for every 2,055 lbs of cement manufactured, 2,044 lbs of carbon dioxide are
released into the atmosphere. Although materials like steel and wood actually produce more
carbon dioxide in production pound for pound, so much more concrete is produced every year
that it leaves these other materials in the shade. Concrete is actually the second most consumed
substance worldwide, with only water seeing more demand. As the graphs from Statista below
illustrate, global cement production has started to level off in recent years after reaching a little
over four billion tons annually. However, US production has continued to rise at a lower rate,
with nearly 90 million tons produced in 2020 (This is not the highest peak since 1995, however,
as the US reached 95 million tons in 2007). Green concrete is made using industrial waste
materials as a partial replacement for other concrete components, like cement or aggregate,
whose production takes a heavier toll on the environment. While some forms of green concrete
are newer, many may not realize that other types have been in use for decades. In this guide to
the different varieties of green concrete, we’ll take you through some of the most well-known
green concrete materials, old and new, as well as the properties they lend the finished product.
First, however, we’ll dig into precisely what green concrete is and how it differs from
traditional concrete.
1
, Fig 1.1.1 GREEN CONCRETE
1.2 Need of Green Concrete:
• The main ingredient in concrete is cement and consists of lime stone.
• During manufacture of cement its ingredients are heated to about 1450
1600^@C
• During this process Carbon Dioxide is released .
• Approximately 1 Kg of concrete releases about 900gms of carbon dioxide
in atmosphere.
Therefore, green concrete came into existence to reduce the emission of carbon dioxide.In
addition to the environmental goals there are a number of environmental intentions. Most
important are: To avoid the use of materials which contain substances on the Environmental
Protection Agency’s list of unwanted materials, not to reduce the recycling ability of green
concrete compared with conventional concrete and not to increase the content of hazardous
substances in the wastewater from concrete production compared with wastewater from
production of existing concrete types. Different concrete types are tested for workability,
changes in workability after 30 min., air-content, compressive strength development, E-
modulus, heat development, homogeneity, water separation, setting time, density and
pumpability. Furthermore, frost testing, chloride penetration and an air void analysis are carried
out for the concretes in the aggressive environmental class. The water/cement ratio,
water/binder ratio and the chloride content are calculated from the mixing report of the precise
mixture proportions and from the chloride content in the different raw materials.
2
, CHAPTER 02
STUDY OF GREEN CONCRETE
Fig 2.1 CO2 Emission 1970-2020
2.2 Materials for Green Concrete
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: Construction materials, components, and systems found locally or
regionally, saving energy and resources in transportation to the project site.
• Salvaged, re-furnished, or re-manufactured: Includes saving a material from disposal
and renovating, repairing, restoring, or generally improving the appearance,
performance, quality, functionality, or value of a product.
• Reusable or recyclable: Select materials that can be easily dismantled and reused or
recycled at the end of their useful life.
Recycled materials that the Industry has found to perform favourably as substitutes for
conventional materials include: fly ash, granulated blast furnace slag, recycled concrete,
demolition waste, micro silica, etc. Generation and use of recycled materials varies from place
to place and from time to time depending on the location and construction activity as well as
3
