14-04-2017, 05:30 AM
I need suggestions regarding this. Where can i get material
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soil stabilization using fly ash ppt
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I need suggestions regarding this. Where can i get material
17-04-2017, 11:44 AM
Fly ash is the residue generated during a combustion process. It consists of fine particles that rise with flue gases. The term fly ash generally refers to fly ash from coal created in coal-fired power plants. It is the most used fly ash in construction and industrial applications.
Soil stabilization is the physical and chemical alteration of soils in order to improve their properties. Soil stabilization with fly ash can reduce contraction potential, increase workability, soil resistance and stiffness. If the fly ash contains more than 10% sulfates, the treated soil has a high initial strength but a reduced durability. Fly ash is also typically used to stabilize subbase or subgrade, and should not be used for surfaces due to the low abrasive resistance of traffic and machinery movements.
The charcoal source and the type of coal combustion process determine the fly ash properties, which further influences the performance of soil stabilization using fly ash. There are two kinds of fly ash: Class C, which is self-sticking and Class F, which is not self-sticking. Class C is the result of the combustion of younger lignite or subbituminous coal. In the presence of water, Class C fly ash hardens and gains strength over time. This type of fly ash contains a significant amount of lime (more than 20%), which is combined with glassy silicates and aluminates. Therefore, when mixed with water, a hydration process occurs, similar to that occurring in the hydration of Portland cement. This hydration reaction results in free lime, which can react with other unreacted pozzolans, silicates and aluminates, available in fly ash.
Class F fly ash is produced from the burning of harder, older coal of anthracite and bituminous coal. This type of fly ash contains less than 20% lime and, therefore, vitreous silica and / or alumina are the only pozzolans present in sufficient amounts. Therefore stabilization of soils through the use of Class F fly ash will only be feasible if additives such as Portland cement, quicklime or hydrated lime are added as a source of free lime. Only then will the existing pozzolans be activated. Hydration and pozzolanic reactions, which occur when fly ash mixes with water, results in products that bind soil grains or agglomerates to increase soil matrix resistance.
The method of soil stabilization with fly ash is potentially harmful to the environment since fly ash contains heavy metals and other compounds that can leach into the soil and bodies of water. Flying ash can damage the vegetation adjacent to the road. Many studies have shown that heavy metals have been leached from fly ash into groundwater and underground aquifers. The extent of leaching and the noxiousness to humans of fly ash leachate is not yet fully known, but is being investigated.
Unlike soil stabilization using fly ash, environmentally sound solutions are created by Global Road Technology. Global Road Technology has been evaluated as environmentally friendly by Environmental Resource Management, the world's leading sustainability consulting firm. They are not toxic to groundwater and do not create dangerous run-off during rainfall. Therefore, GRT products are suitable for urban and ecologically sensitive areas. These products are polymer based agents with long term effects. Global Road Technology offers a range of products that, in addition to contributing to soil stabilization, are suitable for coating, while creating flat, hard, non-dusty and non-slippery surfaces.
Soil stabilization is the physical and chemical alteration of soils in order to improve their properties. Soil stabilization with fly ash can reduce contraction potential, increase workability, soil resistance and stiffness. If the fly ash contains more than 10% sulfates, the treated soil has a high initial strength but a reduced durability. Fly ash is also typically used to stabilize subbase or subgrade, and should not be used for surfaces due to the low abrasive resistance of traffic and machinery movements.
The charcoal source and the type of coal combustion process determine the fly ash properties, which further influences the performance of soil stabilization using fly ash. There are two kinds of fly ash: Class C, which is self-sticking and Class F, which is not self-sticking. Class C is the result of the combustion of younger lignite or subbituminous coal. In the presence of water, Class C fly ash hardens and gains strength over time. This type of fly ash contains a significant amount of lime (more than 20%), which is combined with glassy silicates and aluminates. Therefore, when mixed with water, a hydration process occurs, similar to that occurring in the hydration of Portland cement. This hydration reaction results in free lime, which can react with other unreacted pozzolans, silicates and aluminates, available in fly ash.
Class F fly ash is produced from the burning of harder, older coal of anthracite and bituminous coal. This type of fly ash contains less than 20% lime and, therefore, vitreous silica and / or alumina are the only pozzolans present in sufficient amounts. Therefore stabilization of soils through the use of Class F fly ash will only be feasible if additives such as Portland cement, quicklime or hydrated lime are added as a source of free lime. Only then will the existing pozzolans be activated. Hydration and pozzolanic reactions, which occur when fly ash mixes with water, results in products that bind soil grains or agglomerates to increase soil matrix resistance.
The method of soil stabilization with fly ash is potentially harmful to the environment since fly ash contains heavy metals and other compounds that can leach into the soil and bodies of water. Flying ash can damage the vegetation adjacent to the road. Many studies have shown that heavy metals have been leached from fly ash into groundwater and underground aquifers. The extent of leaching and the noxiousness to humans of fly ash leachate is not yet fully known, but is being investigated.
Unlike soil stabilization using fly ash, environmentally sound solutions are created by Global Road Technology. Global Road Technology has been evaluated as environmentally friendly by Environmental Resource Management, the world's leading sustainability consulting firm. They are not toxic to groundwater and do not create dangerous run-off during rainfall. Therefore, GRT products are suitable for urban and ecologically sensitive areas. These products are polymer based agents with long term effects. Global Road Technology offers a range of products that, in addition to contributing to soil stabilization, are suitable for coating, while creating flat, hard, non-dusty and non-slippery surfaces.
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