Published on Nov 30, 2023
Concrete is one of the versatile heterogeneous materials ever invented by mankind. Concrete is the dominant construction material today with an annual worldwide production of over 4.5 billion metric tons .Concrete being the key material, is used in various types of constructions like highway, buildings ,hydraulic structures etc. It is the material of choice where strength, durability,impermeability, fire resistance and abrasion resistanceare required. Now a days the industrialwastes are rapidly increasing. To utilize and to reduce such type of waste in environment. Cement is replaced by industrial wastes such as flyash and GGBS to obtain higher strength.
The aim of this project work is to construct economically and to determine compressive strength , split tensile strength , flexural strength and durability of concrete mix of M40. FLY ASH and GGBS is limited to the grain size less than 90 micrometer which is to be replaced by cementby varying weight percentage .Our study includes the concept of ternary blending of cement with GGBS and FLY-ASH, this ternary blend cement exploits the beneficial characteristics of both Pozzolanic materials in producing a better concrete.
Keywords : Concrete, Fly Ash, Ground Granulated Blast Furnace Slag, Super Plasticizer, and durability.
The definition of concrete is the mixture of cement, water, additives or sometimes super-plasticizers. It is artificial material. In the beginning it is soft, ductile or fluid, and gradually will be solid. Concrete is considered as durable and strong material and is one of the most popular materials used for construction all around the world. Concrete is exposed to deterioration in some regions,in order to overcome this problem many researches are being carried out.
Water distribution and transport, whetherin gaseous or liquid form, play important roles in the local damage of concrete structures. The production process of cement imparts large amount of Carbon-di-oxide . Since carbon di-oxide is a major pollutant in atmosphere, reducing its formation is important criteria.
The most effective way to decrease the CO2 emission of cement industry, is to substitute a proportion of cement with other materials. These materials called supplementary cementing materials (SCM’s). In our study supplementary cementing materials used are Ground Granulated Blast Furnace Slag (GGBS), Fly Ash (FA). In our experiments we will examine the influence of FLYASH and GGBS on DURABILITY and STRENGTH. In this study we describe the results of examinations and conclusions with GGBS & FLYASH. We will present the experimental program with further activities and works.
Ordinary Portland cement conforming to Indian Standard is used in the present investigation. The cement is tested for its various properties as per Indian Standard code.
The locally available sand is used as fine aggregate in the present investigation. The sand is free from clayey matter, salt and organic impurities. The sand is tested for various properties like specific gravity, bulk density etc., in accordance with Indian Standard 2386-1963(28).
Machine crushed angular granite metal from the local source is used as coarse aggregate (confined to Indian Standard: 383-1970). It is free from impurities such as dust, clay particles and organic matter etc. The coarse aggregate is also tested for its various properties.
Fly ash:
It is a by-product from thermal power plants and it is most available supplementary Cementitious material (SCM)’s in the world approximately 600 Million tonnes. It indicates potential for the use of larger amounts of Fly ash in concrete but at early ages of concrete containing high volume FA effect the properties of concrete like strength development and lower durability performance. Coming to about fly ash it composed of silica, alumina and iron having average particle size of around 35 microns in glassy and spherical shapes. Different researchers made study on fineness of fly ash effect on concrete and it was concluded that as fineness of fly ash increases compressive strength of concrete increases. When fly ash incorporation in concrete it reduces the heat of hydration, increases the fluidity of concrete. In the presence of moisture fly ash gives meta-stable alumino-sillcates that react with calcium ions, this reaction forms silica hydrates.
Ground Granulated Blast Furnace Slag:
It is a by-product obtained in iron manufacture in blast furnace heated iron ore, lime stone, and coke between 1400 to 1600 0C, molten slag quenched by water into fine granulated slag it composed of calcium-alumino silicates of glassy shape. Partial replacement of GGBS to cement in concrete, it makes concrete more durable than conventional concrete but it may slower the initial hydration compared to conventional concrete because of denseness of cement paste. Workability of concrete also becomes good even up to 50 % GGBS replacement level with various w/c ratios. Ground granulated blast furnace slag is by-product from the blast furnaces used to make iron.
Work Plan
The present experimental programme includes casting and testing of specimens for Compression, Split tensile and Flexural strength. Specimens are prepared for M60 grade of concrete. Total of 120 specimens (shown in table 3) with various percentages of Fly ash and Ground Granulated Blast Furnace Slag are casted.
Mixing
Hand mixing is adopted throughout the experimental work. First the materials cement, Fly ash, Ground Granulated Blast Furnace Slag, fine aggregate, coarse aggregate are weighed exactly. First the cement, Flyash and Ground Granulated Blast Furnace Slag are blended with hand and then fine; coarse aggregate is added to this and thoroughly mixed. Water is weighed exactly and added to the dry mix and entire mix is thoroughly mixed till uniformity is arrived.
Casting of Specimens
For casting the cube, standard Cast iron metal moulds of size 150 x 150 x 150mm are to be used. Whereas cylinders and prisms of varying sizes are to be casted respectively. The moulds should be cleaned of dust particles and has to be applied with mineral oil on all sides, before concrete is poured into the mould. Thoroughly mixed concrete are to be filled in to mould. Whole casting procedure is confined to Indian Standard: 10086-1882.
Curing the Specimens
After casting, the moulded specimens are to be stored in the laboratory free from vibration, in moist air and at room temperature for 24 hours. After this period, the specimen are to be removed from themoulds and immediately submerged in the clean fresh water of curing tank. The curing water is renewed after every 5 days. The specimens are cured for 7 and 28 days.
Testing of Specimens
The specimensshould be cured as explained above and are tested as per Indian Standard: 516 – 1959 after removal from the curing tank and allowed to dry under shade.
Compressive strength test: In compressive strength test the cube specimen should be placed with the cast faces of the cubes at right angles to that of the cast in the compression testing machine.
Split tensile strength test: The test should be carried out by using the cylindrical specimens.
Flexural strength test: This test should be conducted on the flexural testing machine. The load should be applied at the middle third points of the effective span of the flexural beam.
Durability test
A long service life is considered synonymous with durability. Since durability under one set of conditions does not necessarily mean durability under another, it is customary to include a general reference to the environment when defining durability. According to ACI Committee 201, durability of Portland cement concrete is defined as its ability to resist weathering action, chemical attack, abrasion, or any other process of deterioration; that is, durable concrete will retain its original form, quality, and serviceability when exposed to its environment. No material is inherently durable; as a result of environmental interactions the microstructure and, consequently, the properties of materials change with time. A material is assumed to reach the end of service life when its properties under given conditions of use have deteriorated to an extent that the continuing use of the material is ruled either unsafe or uneconomical.
Environmental Related Causes of Concrete Durability Problems Durability problems related to environmental causes include the following: steel corrosion, delamination, cracking, carbonation, sulphate attack, chemical attack, scaling, spalling, abrasion and cavitation. Important degradation mechanisms in concrete structures include the following:
1. Freeze-thaw damage (physical effects, weathering).
2. Alkali-aggregate reactions (chemical effects).
3. Sulfate attack (chemical effects).
4. Microbiological induced attack (chemical effects).
5. Corrosion of reinforcing steel embedded in concrete (chemical effects). a) carbonation of concrete b) chloride induced
6. Abrasion (physical effects).
7. Mechanical loads (physical effects).
1. IJIRSET (International Journal of Innovative Research in Science,
2. Engineering and Technology) by Etaveni Madhavi ,M.Akhilesh , G.Vishwanath Sharma, K.Venkatesh
3. International Journal of Engineering Research and Applications (IJERA) ISSN: 2248-9622 Vol. 3, Issue 4, Jul-Aug 2013, pp.285-289 optimum usage of GGBS C&CC 29(2007)505-514, A. Oner, S.Akyuz
4. EFFECT OF PARTIAL REPLACEMENT OF CEMENT BY FLY ASH IN CONCRETE ,Rakesh kumar, Abhishek Kumar, Mohd. Afaque Khan.
5. K. Uma Shankar & K. Suganya, conducted an experimental study on durability tests of flyash and cement.
6. C.Marthong and T.P.Agrawal,conducted an experimental study on durability and shrinkage tests on concrete containing flyash.
7. Md. Moinul Islam and Md. Saiful Islam, gave detailed study on various strengths of concrete mixture.
