Strength And Workability Characteristics Of Super Plasticized Concrete.AshishVivekSukh
The aim of this project is to study the workability and strength characteristics of superplasticized concrete. The investigation is carried out using workability test, compressive strength test, split tensile test and modulus of elasticity test.
Fresh and Hardened Properties of Ground Granulated Blast Furnace Slag Made Co...IJMREMJournal
This research work was carried out on concrete specimens made with different proportion of Ground Granulated Blast Furnace Slag (GGBFS) as a cement substitution in concrete. To accomplish the goal of the research work, overall 75 cubes and 60 cylinders were made. Out of 75 cubes and 60 cylinders, 15 cubes and 12 cylinders were cast for control concrete, and 60 cubes and 48 cylinders were cast by replacing 5,10,15 and 20% of cement with GGBFS. The cubes and cylinder specimens were 100x100x100 mm and 100x200 mm respectively, and mix design was done for 28 Mpa. All specimens were tested at 3. 7, 28 and 90 days of curing ages. The fresh properties such as workability and hardened properties such as compressive and tensile strength of all mixes were determined. Tests results showed that the workability of the concrete mixes made with GGBFS was higher than control mix. As the percentage of GGBFS increased the workability also increased. Hardened properties of concrete mixes made with GGBFS was lower than control concrete at early ages of curing. At the later age, hardened properties of GGBFS made concrete was more than control concrete. Furthermore, water absorption and density of GGBFS made concrete was lower than control concrete.
Strength And Workability Characteristics Of Super Plasticized Concrete.AshishVivekSukh
The aim of this project is to study the workability and strength characteristics of superplasticized concrete. The investigation is carried out using workability test, compressive strength test, split tensile test and modulus of elasticity test.
Fresh and Hardened Properties of Ground Granulated Blast Furnace Slag Made Co...IJMREMJournal
This research work was carried out on concrete specimens made with different proportion of Ground Granulated Blast Furnace Slag (GGBFS) as a cement substitution in concrete. To accomplish the goal of the research work, overall 75 cubes and 60 cylinders were made. Out of 75 cubes and 60 cylinders, 15 cubes and 12 cylinders were cast for control concrete, and 60 cubes and 48 cylinders were cast by replacing 5,10,15 and 20% of cement with GGBFS. The cubes and cylinder specimens were 100x100x100 mm and 100x200 mm respectively, and mix design was done for 28 Mpa. All specimens were tested at 3. 7, 28 and 90 days of curing ages. The fresh properties such as workability and hardened properties such as compressive and tensile strength of all mixes were determined. Tests results showed that the workability of the concrete mixes made with GGBFS was higher than control mix. As the percentage of GGBFS increased the workability also increased. Hardened properties of concrete mixes made with GGBFS was lower than control concrete at early ages of curing. At the later age, hardened properties of GGBFS made concrete was more than control concrete. Furthermore, water absorption and density of GGBFS made concrete was lower than control concrete.
International Journal of Computational Engineering Research(IJCER) is an intentional online Journal in English monthly publishing journal. This Journal publish original research work that contributes significantly to further the scientific knowledge in engineering and Technology
An Experimental Investigation on Strength Characteristics of Concrete with Pa...ijsrd.com
One of the approaches in improving the durability of concrete is to use blended cement materials such as fly ash, silica fume, slag and more recently, metakaolin. By changing the chemistry and microstructure of concrete, pozzolans reduce the capillary porosity of the cementitious system and make them less permeable to exterior chemical sources as well as reducing the internal chemical incompatilities such as alkali-silica reaction. The concrete industry is known to leave an enormous environmental footprint on Planet Earth. First, there are the sheer volumes of material needed to produce the billions of tons of concrete worldwide each year. Then there are the CO2 emissions caused during the production of Portland cement. Together with the energy requirements, water consumption and generation of construction and demolition waste, these factors contribute to the general appearance that concrete is not particularly environmentally friendly or compatible with the demands of sustainable development. Thus, use of these supplementary cementitious materials can reduce the effects of cement causing severe environmental impact. This study presents the results of different mechanical properties of concrete such as compressive strength, split tensile strength and flexural concrete by partially replacing cement with metakaolin and silica fume. The replacement of metakaolin is varied from 10%, 15%, 20% and 25% and silica fume from 6%, 8% and 10%. The property of concrete in fresh state that is the workability is also studied during the present investigation. The optimum doses of silica fume and metakaolin in combination were found to be 6% and 15% (by weight) respectively, when used as part replacement of ordinary Portland cement.
Experimental Investigations of Mechanical properties on Micro silica (Silica ...IOSR Journals
Abstract : The Now a day, we need to look at a way to reduce the cost of building materials, particularly
cement is currently so high that only rich people and governments can afford meaningful construction. Studies
have been carried out to investigate the possibility of utilizing a broad range of materials as partial replacement
materials for cement in the production of concrete. This study investigated the strength properties of Silica fume
and fly ash concrete. This work primarily deals with the strength characteristics such as compressive, Split
tensile and flexural strength. High performance concrete a set of 7 different concrete mixture were cast and
tested with different cement replacement levels (0%, 2.5%, 5%, 7.5%, 10% 12.5% and15%) of Fly ash (FA) with
silica fume (SF) as addition ( 0%,5%,10 % ,15% ,25and 30%) by wt of Cement and/or each trial super
plasticizer has been added at constant values to achieve a constant range of slump for desired work ability with
a constant water-binder (w/b) ratio of 0.30.Specimens were produced and cured in a curing tank for 3, 7, 14
and 28 days. The cubes were subjected to compressive strength tests after density determination at 3,7,14 and
28 days respectively. The chemical composition and physical composition of micro silica, FlyAsh and cement
were determined. The density of the concrete decreased with increased in percentage of micro silica and Fly ash
replacement up to 15%. Increase in the level of micro silica fume and Fly ash replacement between 30% to 45%
led to a reduction in the compressive strength of hardened concrete. This study has shown that between 15 to
22.5% replacement levels, concrete will develop strength sufficient for construction purposes. Its use will lead
to a reduction in cement quantity required for construction purposes and hence sustainability in the
construction industry as well as aid economic construction.
Keywords: Durability, Fly Ash, High performance Concrete, Silica Fume/Micro Silica, Density, water
absorption
Experimental investigation on effect of mineral admixtures on high performanc...eSAT Journals
Abstract Now a day's high performance concrete is globally used in the infrastructure industry for strong and durable structure, to produced high performance concrete various supplementary cementitious material are used as mineral admixture. This research involves the use of Fly ash, Alccofine and Silica fume at various proportions to enhance the compressive strength of high performance concrete. the investigation was carried out by replacing 10% fly ash along with 17% of alccofine and 10% fly ash along with 17% of silica fume by weight of cementitious material. To cover a wide range of compressive strength of concrete various water binder ratio (W/b) of 0.25, 0.3 and 0.35 were used. The effect of various parameters such as percentage replacement of mineral admixture, water to binder ratio and corresponding compressive strength is studied on fresh and hardened state of concrete. The study mainly consisted of establishing relation between these parameters graphically. Investigation demonstrates that alcofine performs batter than that of silica fume along with fly ash in fresh and harden state of concrete. Keywords: High Performance Concrete, Fly Ash, Alccofine, Silica Fume, workability, Compressive strength
Study of Macro level Properties of SCC using GGBS and Lime stone powderIJERD Editor
One of the major environmental concerns is the disposal of the waste materials and utilization of
industrial by products. Lime stone quarries will produce millions of tons waste dust powder every year. Having
considerable high degree of fineness in comparision to cement this material may be utilized as a partial
replacement to cement. For this purpose an experiment is conducted to investigate the possibility of using lime
stone powder in the production of SCC with combined use GGBS and how it affects the fresh and mechanical
properties of SCC. First SCC is made by replacing cement with GGBS in percentages like 10, 20, 30, 40, 50 and
by taking the optimum mix with GGBS lime stone powder is blended to mix in percentages like 5, 10, 15, 20 as
a partial replacement to cement. Test results shows that the SCC mix with combination of 30% GGBS and 15%
limestone powder gives maximum compressive strength and fresh properties are also in the limits prescribed by
the EFNARC.
Experimental Study on Durability Characteristics of High Performance Concrete...theijes
High performance concrete (HPC) is developed gradually over the last 15 years with respect to production of concrete with higher and higher strength. To enhance the properties such as durability, strength, workability, economy has increased due to the usage of mineral admixtures in making high performance concrete. The scope of the present study is to investigate the effect of mineral admixtures and by-products towards the performance of HPC. An effort has been made to concentrate on the mineral admixture of silica fume towards their pozzolanic reaction and industrial by-product of bottom ash and steel slag towards their hydration reaction can be contributed towards their strength and durability properties. The strength characteristics such as compressive strength, tensile strength and flexural strength were investigated to find the optimum replacement of mineral admixture and by-product admixture. HPC with mineral admixture of silica fume at the replacement levels of 0%, 5%, 10%, 15% & 20% were studied at the age of 28 days and industrial by-products of bottom ash and steel slag aggregate at the replacement level of 10%, 20%, 30%, 40% & 50% were studied at the age of 28 days. There were a total of 15 mixes created with different material contents. Out of 14 were HPC mixes and 1 were conventional concrete mixes. Finally strength has enhanced with the mix of silica fume can replaced by cement with 5% and bottom ash and steel slag can replaced by fine and coarse aggregate with 10% can be achieved higher strength when compared with other percentage of mixes. The combination mixes can be classified as binary and ternary mixes. Binary mixes involved combinations of silica fume and bottom ash (SF+BA), silica fume and steel slag aggregate (SF+SSA), bottom ash and steel slag aggregate (BA+SSA) and Ternary mixes involved combination of three materials such as silica fume, bottom ash and steel slag aggregate (SF+BA+SSA) in High performance concrete. The investigation revealed that the combined use of silica fume, bottom ash and steel slag aggregate improved the mechanical properties of HPC and thus there 3 materials may use as a partial replacement material in making HPC. The durability studies such as acid resistance, salt resistance, sulphate resistance & water absorption were conducted. From the experimental investigation, it was observed that mineral admixture of silica fume and industrial by-products of bottom ash & steel slag aggregate plays a vital role in improving the strength and durability parameter itself.
EFFECT OF SILICA FUME ON RHEOLOGY AND MECHANICAL PROPERTY OF SELF COMPACTING ...IAEME Publication
The usage of an extensive group of industrial mineral residues (silica fume and fly ash) and other products significantly increases the rheological performance of concrete. This research is supposed to take a look at Rheology and Strengthened Properties of Self Compacting Concrete with Silica fume. This examination commenced with 4 groups of Self Compacting Concrete changed with diverse probabilities of Silica fume (5%, 10%,15%, and 20%). The rheological properties of self-compacting concrete are investigated experimentally using the slump flow diameter, the U box test, the V funnel test, and the L box test. Compressive strength and flexural strength are the strengthened properties experimentally examined. In this study, we observed the suitable percent of silica fume, which offers advanced rheological characteristics of Self Compacting Concrete as equated to Conventional Self Compacting Concrete. Our experimental results show, by the replacing 15% of silica fume with the weight of cement will increase both Rheological Properties and strengthened Properties of SCC.
An Experimental Study on Durability of Concrete Using Fly Ash & GGBS for M30 ...IJERD Editor
Concrete when subjected to severe environments its durability can significantly decline due to
degradation. Degradation of concrete structures by corrosion is a serious problem and has major economic
implications. In this study, an attempt has been made to study the durability of concrete using the mineral
admixtures like Fly Ash & Ground Granulated Blast Furnace Slag (GGBS) for M30 grade concrete.Cube
Specimens were casted and are immersed in normal water, sea water, H2SO4 of various concentrations and were
tested after 7 days, 28 days & 60 days.
Study of Mechanical Properties in SCC by Blending Cement Partially With Fly A...IJSRD
The development of self-compacting concrete has been one of the most important materials in the modern building industry. The purpose of this concrete concept is to decrease the risk due to human factor. The use of SCC is spreading worldwide because of its very attractive properties. In the present investigation Blended SCC is the one in which some percentage of cement content used for the concrete is replaced by any of the mineral admixtures. Here, the present study to development of blended self-compacting concrete by replaced in the mineral admixtures using Fly ash 0-30% and metakaolin 0-30% as the weight of cement. Study the rheological properties and mechanical properties of developed blended SCC mixes in the laboratory condition and different curing ages. In recent years, many researchers have established that the use of supplementary cementatious materials (SCMs) like blast furnace slag, silica fume, metakaolin (MK), fly ash (FA) and rice husk ash (RHA) etc. can, not only improve the various properties of concrete both in its fresh and hardened states, but also can contribute to economy in construction costsruning.
International Journal of Engineering Research and Applications (IJERA) is an open access online peer reviewed international journal that publishes research and review articles in the fields of Computer Science, Neural Networks, Electrical Engineering, Software Engineering, Information Technology, Mechanical Engineering, Chemical Engineering, Plastic Engineering, Food Technology, Textile Engineering, Nano Technology & science, Power Electronics, Electronics & Communication Engineering, Computational mathematics, Image processing, Civil Engineering, Structural Engineering, Environmental Engineering, VLSI Testing & Low Power VLSI Design etc.
Analysis the Effect of Steel Fibre and Marble Dust with Strength of Pavement ...ijtsrd
The thrust nowadays is to produce thinner and green pavement sections of better quality, which can carry the heavy loads. The high strength steel fibre reinforced concrete is a concrete having compressive strength greater than 40MPa, made of hydraulic cements and containing fine and coarse aggregates; and discontinuous, unconnected, randomly distributed steel fibres. The present study aims at, developing pavement quality concrete mixtures incorporating marble dust as partial replacement of cement as well as steel fibres. The aim is to the design of slab thickness of PQC pavement using the achieved flexural strength of the concrete mixtures. In this study, the flexural, compressive and split tensile strength for pavement quality concrete mixtures for different percentage of steel fibres and replacement of cement with marble dust are reported. It is found out the maximum increase in flexure strength, compressive strength and split tensile strength is for 0% Marble Dust and 1% Steel fibre. Also it has been possible to achieve savings in cement by replacing it with marble dust and adding fibres. This study also shows that in view of the high flexural strength, high values of compressive strength and high values of split tensile strength, higher load carrying capacity and higher life expectancy, the combination of 10 to 20% marble dust replacement along with addition of 0.5 to 1% steel fibres is ideal for design of Pavement Quality Concrete (PQC). Krishan Kumar | Sumesh Jain"Analysis the Effect of Steel Fibre and Marble Dust with Strength of Pavement Quality Concrete" Published in International Journal of Trend in Scientific Research and Development (ijtsrd), ISSN: 2456-6470, Volume-1 | Issue-4 , June 2017, URL: http://www.ijtsrd.com/papers/ijtsrd152.pdf http://www.ijtsrd.com/engineering/civil-engineering/152/analysis-the-effect-of-steel-fibre-and-marble-dust-with-strength-of-pavement-quality-concrete/krishan-kumar
Study of Boron Based Superconductivity and Effect of High Temperature Cuprate...IOSR Journals
This paper illustrates the main normal and Boron superconducting state temperature properties of magnesium diboride, a substance known since early 1950's, but lately graded to be superconductive at a remarkably high critical temperature Tc=40K for a binary synthesis. What makes MgB2 so special? Its high Tc, simple crystal construction, large coherence lengths, high serious current densities and fields, lucidity of surface boundaries to current promises that MgB2 will be a good material for both large scale applications and electronic devices. Throughout the last seven month, MgB2 has been fabricated in various shape, bulk, single crystals, thin films, ribbons and wires. The largest critical current densities >10MA/cm2 and critical fields 40T are achieved for thin films. The anisotropy attribution inferred from upper critical field measurements is still to be resolved, a wide range of values being reported, γ = 1.2 ÷ 9. Also there is no consensus about the existence of a single anisotropic or double energy cavity. One central issue is whether or not MgB2 represents a new class of superconductors, being the tip of an iceberg that waits to be discovered. Until now MgB2 holds the record of the highest Tc among simple binary synthesis. However, the discovery of superconductivity in MgB2 revived the interest in non-oxides and initiated a search for superconductivity in related materials, several synthesis being already announced to become superconductive: TaB2, BeB2.75, C-S composites, and the elemental B under pressure.
International Journal of Computational Engineering Research(IJCER) is an intentional online Journal in English monthly publishing journal. This Journal publish original research work that contributes significantly to further the scientific knowledge in engineering and Technology
An Experimental Investigation on Strength Characteristics of Concrete with Pa...ijsrd.com
One of the approaches in improving the durability of concrete is to use blended cement materials such as fly ash, silica fume, slag and more recently, metakaolin. By changing the chemistry and microstructure of concrete, pozzolans reduce the capillary porosity of the cementitious system and make them less permeable to exterior chemical sources as well as reducing the internal chemical incompatilities such as alkali-silica reaction. The concrete industry is known to leave an enormous environmental footprint on Planet Earth. First, there are the sheer volumes of material needed to produce the billions of tons of concrete worldwide each year. Then there are the CO2 emissions caused during the production of Portland cement. Together with the energy requirements, water consumption and generation of construction and demolition waste, these factors contribute to the general appearance that concrete is not particularly environmentally friendly or compatible with the demands of sustainable development. Thus, use of these supplementary cementitious materials can reduce the effects of cement causing severe environmental impact. This study presents the results of different mechanical properties of concrete such as compressive strength, split tensile strength and flexural concrete by partially replacing cement with metakaolin and silica fume. The replacement of metakaolin is varied from 10%, 15%, 20% and 25% and silica fume from 6%, 8% and 10%. The property of concrete in fresh state that is the workability is also studied during the present investigation. The optimum doses of silica fume and metakaolin in combination were found to be 6% and 15% (by weight) respectively, when used as part replacement of ordinary Portland cement.
Experimental Investigations of Mechanical properties on Micro silica (Silica ...IOSR Journals
Abstract : The Now a day, we need to look at a way to reduce the cost of building materials, particularly
cement is currently so high that only rich people and governments can afford meaningful construction. Studies
have been carried out to investigate the possibility of utilizing a broad range of materials as partial replacement
materials for cement in the production of concrete. This study investigated the strength properties of Silica fume
and fly ash concrete. This work primarily deals with the strength characteristics such as compressive, Split
tensile and flexural strength. High performance concrete a set of 7 different concrete mixture were cast and
tested with different cement replacement levels (0%, 2.5%, 5%, 7.5%, 10% 12.5% and15%) of Fly ash (FA) with
silica fume (SF) as addition ( 0%,5%,10 % ,15% ,25and 30%) by wt of Cement and/or each trial super
plasticizer has been added at constant values to achieve a constant range of slump for desired work ability with
a constant water-binder (w/b) ratio of 0.30.Specimens were produced and cured in a curing tank for 3, 7, 14
and 28 days. The cubes were subjected to compressive strength tests after density determination at 3,7,14 and
28 days respectively. The chemical composition and physical composition of micro silica, FlyAsh and cement
were determined. The density of the concrete decreased with increased in percentage of micro silica and Fly ash
replacement up to 15%. Increase in the level of micro silica fume and Fly ash replacement between 30% to 45%
led to a reduction in the compressive strength of hardened concrete. This study has shown that between 15 to
22.5% replacement levels, concrete will develop strength sufficient for construction purposes. Its use will lead
to a reduction in cement quantity required for construction purposes and hence sustainability in the
construction industry as well as aid economic construction.
Keywords: Durability, Fly Ash, High performance Concrete, Silica Fume/Micro Silica, Density, water
absorption
Experimental investigation on effect of mineral admixtures on high performanc...eSAT Journals
Abstract Now a day's high performance concrete is globally used in the infrastructure industry for strong and durable structure, to produced high performance concrete various supplementary cementitious material are used as mineral admixture. This research involves the use of Fly ash, Alccofine and Silica fume at various proportions to enhance the compressive strength of high performance concrete. the investigation was carried out by replacing 10% fly ash along with 17% of alccofine and 10% fly ash along with 17% of silica fume by weight of cementitious material. To cover a wide range of compressive strength of concrete various water binder ratio (W/b) of 0.25, 0.3 and 0.35 were used. The effect of various parameters such as percentage replacement of mineral admixture, water to binder ratio and corresponding compressive strength is studied on fresh and hardened state of concrete. The study mainly consisted of establishing relation between these parameters graphically. Investigation demonstrates that alcofine performs batter than that of silica fume along with fly ash in fresh and harden state of concrete. Keywords: High Performance Concrete, Fly Ash, Alccofine, Silica Fume, workability, Compressive strength
Study of Macro level Properties of SCC using GGBS and Lime stone powderIJERD Editor
One of the major environmental concerns is the disposal of the waste materials and utilization of
industrial by products. Lime stone quarries will produce millions of tons waste dust powder every year. Having
considerable high degree of fineness in comparision to cement this material may be utilized as a partial
replacement to cement. For this purpose an experiment is conducted to investigate the possibility of using lime
stone powder in the production of SCC with combined use GGBS and how it affects the fresh and mechanical
properties of SCC. First SCC is made by replacing cement with GGBS in percentages like 10, 20, 30, 40, 50 and
by taking the optimum mix with GGBS lime stone powder is blended to mix in percentages like 5, 10, 15, 20 as
a partial replacement to cement. Test results shows that the SCC mix with combination of 30% GGBS and 15%
limestone powder gives maximum compressive strength and fresh properties are also in the limits prescribed by
the EFNARC.
Experimental Study on Durability Characteristics of High Performance Concrete...theijes
High performance concrete (HPC) is developed gradually over the last 15 years with respect to production of concrete with higher and higher strength. To enhance the properties such as durability, strength, workability, economy has increased due to the usage of mineral admixtures in making high performance concrete. The scope of the present study is to investigate the effect of mineral admixtures and by-products towards the performance of HPC. An effort has been made to concentrate on the mineral admixture of silica fume towards their pozzolanic reaction and industrial by-product of bottom ash and steel slag towards their hydration reaction can be contributed towards their strength and durability properties. The strength characteristics such as compressive strength, tensile strength and flexural strength were investigated to find the optimum replacement of mineral admixture and by-product admixture. HPC with mineral admixture of silica fume at the replacement levels of 0%, 5%, 10%, 15% & 20% were studied at the age of 28 days and industrial by-products of bottom ash and steel slag aggregate at the replacement level of 10%, 20%, 30%, 40% & 50% were studied at the age of 28 days. There were a total of 15 mixes created with different material contents. Out of 14 were HPC mixes and 1 were conventional concrete mixes. Finally strength has enhanced with the mix of silica fume can replaced by cement with 5% and bottom ash and steel slag can replaced by fine and coarse aggregate with 10% can be achieved higher strength when compared with other percentage of mixes. The combination mixes can be classified as binary and ternary mixes. Binary mixes involved combinations of silica fume and bottom ash (SF+BA), silica fume and steel slag aggregate (SF+SSA), bottom ash and steel slag aggregate (BA+SSA) and Ternary mixes involved combination of three materials such as silica fume, bottom ash and steel slag aggregate (SF+BA+SSA) in High performance concrete. The investigation revealed that the combined use of silica fume, bottom ash and steel slag aggregate improved the mechanical properties of HPC and thus there 3 materials may use as a partial replacement material in making HPC. The durability studies such as acid resistance, salt resistance, sulphate resistance & water absorption were conducted. From the experimental investigation, it was observed that mineral admixture of silica fume and industrial by-products of bottom ash & steel slag aggregate plays a vital role in improving the strength and durability parameter itself.
EFFECT OF SILICA FUME ON RHEOLOGY AND MECHANICAL PROPERTY OF SELF COMPACTING ...IAEME Publication
The usage of an extensive group of industrial mineral residues (silica fume and fly ash) and other products significantly increases the rheological performance of concrete. This research is supposed to take a look at Rheology and Strengthened Properties of Self Compacting Concrete with Silica fume. This examination commenced with 4 groups of Self Compacting Concrete changed with diverse probabilities of Silica fume (5%, 10%,15%, and 20%). The rheological properties of self-compacting concrete are investigated experimentally using the slump flow diameter, the U box test, the V funnel test, and the L box test. Compressive strength and flexural strength are the strengthened properties experimentally examined. In this study, we observed the suitable percent of silica fume, which offers advanced rheological characteristics of Self Compacting Concrete as equated to Conventional Self Compacting Concrete. Our experimental results show, by the replacing 15% of silica fume with the weight of cement will increase both Rheological Properties and strengthened Properties of SCC.
An Experimental Study on Durability of Concrete Using Fly Ash & GGBS for M30 ...IJERD Editor
Concrete when subjected to severe environments its durability can significantly decline due to
degradation. Degradation of concrete structures by corrosion is a serious problem and has major economic
implications. In this study, an attempt has been made to study the durability of concrete using the mineral
admixtures like Fly Ash & Ground Granulated Blast Furnace Slag (GGBS) for M30 grade concrete.Cube
Specimens were casted and are immersed in normal water, sea water, H2SO4 of various concentrations and were
tested after 7 days, 28 days & 60 days.
Study of Mechanical Properties in SCC by Blending Cement Partially With Fly A...IJSRD
The development of self-compacting concrete has been one of the most important materials in the modern building industry. The purpose of this concrete concept is to decrease the risk due to human factor. The use of SCC is spreading worldwide because of its very attractive properties. In the present investigation Blended SCC is the one in which some percentage of cement content used for the concrete is replaced by any of the mineral admixtures. Here, the present study to development of blended self-compacting concrete by replaced in the mineral admixtures using Fly ash 0-30% and metakaolin 0-30% as the weight of cement. Study the rheological properties and mechanical properties of developed blended SCC mixes in the laboratory condition and different curing ages. In recent years, many researchers have established that the use of supplementary cementatious materials (SCMs) like blast furnace slag, silica fume, metakaolin (MK), fly ash (FA) and rice husk ash (RHA) etc. can, not only improve the various properties of concrete both in its fresh and hardened states, but also can contribute to economy in construction costsruning.
International Journal of Engineering Research and Applications (IJERA) is an open access online peer reviewed international journal that publishes research and review articles in the fields of Computer Science, Neural Networks, Electrical Engineering, Software Engineering, Information Technology, Mechanical Engineering, Chemical Engineering, Plastic Engineering, Food Technology, Textile Engineering, Nano Technology & science, Power Electronics, Electronics & Communication Engineering, Computational mathematics, Image processing, Civil Engineering, Structural Engineering, Environmental Engineering, VLSI Testing & Low Power VLSI Design etc.
Analysis the Effect of Steel Fibre and Marble Dust with Strength of Pavement ...ijtsrd
The thrust nowadays is to produce thinner and green pavement sections of better quality, which can carry the heavy loads. The high strength steel fibre reinforced concrete is a concrete having compressive strength greater than 40MPa, made of hydraulic cements and containing fine and coarse aggregates; and discontinuous, unconnected, randomly distributed steel fibres. The present study aims at, developing pavement quality concrete mixtures incorporating marble dust as partial replacement of cement as well as steel fibres. The aim is to the design of slab thickness of PQC pavement using the achieved flexural strength of the concrete mixtures. In this study, the flexural, compressive and split tensile strength for pavement quality concrete mixtures for different percentage of steel fibres and replacement of cement with marble dust are reported. It is found out the maximum increase in flexure strength, compressive strength and split tensile strength is for 0% Marble Dust and 1% Steel fibre. Also it has been possible to achieve savings in cement by replacing it with marble dust and adding fibres. This study also shows that in view of the high flexural strength, high values of compressive strength and high values of split tensile strength, higher load carrying capacity and higher life expectancy, the combination of 10 to 20% marble dust replacement along with addition of 0.5 to 1% steel fibres is ideal for design of Pavement Quality Concrete (PQC). Krishan Kumar | Sumesh Jain"Analysis the Effect of Steel Fibre and Marble Dust with Strength of Pavement Quality Concrete" Published in International Journal of Trend in Scientific Research and Development (ijtsrd), ISSN: 2456-6470, Volume-1 | Issue-4 , June 2017, URL: http://www.ijtsrd.com/papers/ijtsrd152.pdf http://www.ijtsrd.com/engineering/civil-engineering/152/analysis-the-effect-of-steel-fibre-and-marble-dust-with-strength-of-pavement-quality-concrete/krishan-kumar
Study of Boron Based Superconductivity and Effect of High Temperature Cuprate...IOSR Journals
This paper illustrates the main normal and Boron superconducting state temperature properties of magnesium diboride, a substance known since early 1950's, but lately graded to be superconductive at a remarkably high critical temperature Tc=40K for a binary synthesis. What makes MgB2 so special? Its high Tc, simple crystal construction, large coherence lengths, high serious current densities and fields, lucidity of surface boundaries to current promises that MgB2 will be a good material for both large scale applications and electronic devices. Throughout the last seven month, MgB2 has been fabricated in various shape, bulk, single crystals, thin films, ribbons and wires. The largest critical current densities >10MA/cm2 and critical fields 40T are achieved for thin films. The anisotropy attribution inferred from upper critical field measurements is still to be resolved, a wide range of values being reported, γ = 1.2 ÷ 9. Also there is no consensus about the existence of a single anisotropic or double energy cavity. One central issue is whether or not MgB2 represents a new class of superconductors, being the tip of an iceberg that waits to be discovered. Until now MgB2 holds the record of the highest Tc among simple binary synthesis. However, the discovery of superconductivity in MgB2 revived the interest in non-oxides and initiated a search for superconductivity in related materials, several synthesis being already announced to become superconductive: TaB2, BeB2.75, C-S composites, and the elemental B under pressure.
IOSR journal of VLSI and Signal Processing (IOSRJVSP) is an open access journal that publishes articles which contribute new results in all areas of VLSI Design & Signal Processing. The goal of this journal is to bring together researchers and practitioners from academia and industry to focus on advanced VLSI Design & Signal Processing concepts and establishing new collaborations in these areas.
Academic Libraries: Engine Breed Spuring Innovation for Competitiveness and S...IOSR Journals
Abstract: The research was designed to unveil out how academic libraries have assisted institutions in bring up candidates to work in industrial capabilities towards the achievement of competitiveness and sustainable economic growth in society. This study was drawn from the extensive literature review and case studies to discuss the following economic value of accessing information using the library; innovation and services in academic libraries; initiatives, resources and activities that facilitate access to information in the library; FUTO Library and library responding to academic programmes. The following research questions helped ascertain what has made the academic libraries tick in this direction and to find answers to them; what status of people does the library have? To what extent material resources is provided and used by the library patrons? What ICT services are been offered by the library and of what purpose are they offered? What strategy development implied by the library to meet patron’s needs? What are the obstacles the library may encounter in the process to achieve competitiveness and sustainability to serve library patrons? Frequency and percentages were deployed for the study due is within the study environment area. Collection of Data was through the use of questionnaire developed by the researchers. Ninety-five copies of the questionnaires were distributed to staff of FUTO Library, out of which 85 were returned and found useful. Finding was analyzed and results ascertained. Keyword: Library, growth, process, ICT, resources, services, innovation
Impact and Performance of Linen Fiber Reinforced Concrete in Slender ColumnsAJSERJournal
This study was consisted of two phases, revealed the behavior of Self-Compacting Concrete (SCC)
specimens of small-diameter slender column to achieve high quality concrete properties without using concrete
vibrator. The first phase investigated the effect of linen fiber on the rheological properties of SCC using two mixes types:
type I mix: without lime powder, and type II mix: with 20% lime as a replacement of cement content. The linen fiber was
contented of 0, 2, and 4 Kg/m³. In the second phase, the type II mix was used to cast three columns; one with plain SCC
and the other two with 2 and 4 Kg/m³ fiber contents. These columns were cured and cut in a certain manner to obtain 7
cylinders 150 × 300 mm and 8 slices 20 mm thickness. The cylinders were used to measure the distribution of unit
weight, compressive strength, and ultrasonic pulse velocity (UPV) along the column height. The rheological properties
of SCC were reduced with the additives of fibers to the mix constituents, but the properties of Fiber reinforced SelfCompacted Concrete (FSCC) were tested at 4 Kg/m³ fiber content. The distribution of unit weight, compressive strength,
and UPV provided good compaction of concrete. Also, the distribution of coarse aggregate at bottom, middle and top
sections of columns were uniformly distributed.
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and High range water reducing admixture (HRWR). It involves the process of determining experimentally the
most suitable concrete mixes in order to achieve the targeted mean strength. In this research work 53 grade
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were obtained.
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The usage of an extensive group of industrial mineral residues (silica fume and fly ash) and other products significantly increases the rheological performance of concrete. This research is supposed to take a look at Rheology and Strengthened Properties of Self Compacting Concrete with Silica fume. This examination commenced with 4 groups of Self Compacting Concrete changed with diverse probabilities of Silica fume (5%, 10%,15%, and 20%). The rheological properties of self-compacting concrete are investigated experimentally using the slump flow diameter, the U box test, the V funnel test, and the L box test. Compressive strength and flexural strength are the strengthened properties experimentally examined. In this study, we observed the suitable percent of silica fume, which offers advanced rheological characteristics of Self Compacting Concrete as equated to Conventional Self Compacting Concrete. Our experimental results show, by the replacing 15% of silica fume with the weight of cement will increase both Rheological Properties and strengthened Properties of SCC.
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From Siloed Products to Connected Ecosystem: Building a Sustainable and Scala...
L0124598103
1. IOSR Journal of Mechanical and Civil Engineering (IOSR-JMCE)
e-ISSN: 2278-1684,p-ISSN: 2320-334X, Volume 12, Issue 4 Ver. V (Jul. - Aug. 2015), PP 98-103
www.iosrjournals.org
DOI: 10.9790/1684-124598103 www.iosrjournals.org 98 | Page
Effect of Sudanese Aggregate on Production of High Strength
Concrete
Ali Ahmed. A. Ahmed 1
, Salih Elhadi.M.Ahmed 2
1
(Senior Concrete Engineer at SMEC International Pty .Ltd-Sudan, Sudan)
2
(Professor of structural engineering / Sudan university for science and technology, Sudan)
Abstract: The purpose of this paper was to study the effect of use of Sudanese aggregate with supplementary
cementitious materials silica fume and fly ash in high strength concrete mixes, and study the effect of water-
cementitious materials ratio and concrete ingredients in compressive strength, workability and cost of high
strength concrete. The concrete specimens were tested at different age levels, 7-days and 28-days for
mechanical properties of concrete, namely, cube compressive strength, fresh properties, slump test.
This paper presents a part of an ongoing experimental laboratory investigations being carried out for
production and characterization of high strength concrete for heightening of an existing concrete dam in the
south of Sudan. Brief description of the main features of the dam and concrete works are presented. Hundreds
of specimens were performed and tested using local Sudanese aggregates with addition of supplementary
cementitious materials (Silica Fume and Fly Ash) and Super plasticizers. Various percentages of silica fume
and fly ash were added at different water/cementitious (w/cm) ratios. Thirty three trial mix designs of grade 80
MPa according to ACI 211.4, high strength concrete had been success fully produced and their mechanical
properties were measured and documented. The results have offered an important insight for relationship and
influence of components mixture in properties of high strength concrete and in cost. The effect of w/cm ratio on
strength of high strength concrete was also highlighted. Optimum replacement percentage is not a constant one
but depends on the w/cm ratio of the mix. It is concluded that local concrete materials, in combination with
supplementary cementitious materials can be utilized in producing high strength concrete in Sudan,
water/cementitious ratio (w/cm)is in inverse relationship with compressive strength and its effect is very strong
in strength, silica fume had a positive effect in producing high strength concrete and contributed to both short
and long-term properties of concrete, fly ash had inverse relationship with28 days compressive strength, fine
aggregate had an inverse relationship with compressive strength and local Sudanese coarse aggregate had a
strong positive effect in producing high strength concrete. Also the effect of concrete ingredients in slump and
cost were studied.
Keywords– Compressive strength, Fly ash, High strength concrete, Silica fume, Super- plasticizers
I. Introduction
In conventional concrete technology, the strength of the paste is a function of its water/ cement ratio.
This is true also for high strength concrete, but it is also the effect of the porosity within the paste, the particle
size distribution of the crystalline phases and the presence of inhomogeneities within the hydrated paste that
must be considered in detail. (1)
A reduction in water/cement ratio will produce a paste in which the cementitious
particles are initially closer together in the freshly mixed concrete. This results, in less capillary porosity in the
hardened paste and hence a greater strength. (1)
When the transition zone between the paste and the aggregate is
improved the transfer of stresses from the paste to the aggregate particles becomes more effective. Consequently
the mechanical properties of the aggregate particles themselves may be the „weakest link‟ leading to limitation
of achievable concrete strength. Fracture surfaces in HSC often pass through aggregate particles rather than
around them. (1)
Crushed rock aggregates are generally preferred to smooth gravels as there is some evidence that
the strength of the transition zone is weakened by smooth aggregates. The aggregate should have a high intrinsic
strength and granites, basalts and limestones have been used successfully, as have crushed glacial gravels. (1)
Super-plasticizers / high range water reducers should be used to achieve maximum water reduction.
Supplementary cementatious materials are materials that, when blended with Portland cement,
contribute to the properties of concrete through hydraulic activity, pozzolanic activity, or both. Hydraulic
activity occurs when phases in the supplementary cementatious materials chemically react with water, forming
cementitious hydration products similar to those formed through hydration of Portland cement. This is in
contrast to pozzolanic activity, which is characterized by the reaction between siliceous or aluminosiliceous
material in the supplementary cementatious materials with calcium hydroxide (a reaction product from the
hydration of Portland cement), forming calcium silicate hydrate and other cementitious compounds. Calcium
silicate hydrate is a more desirable hydration product and thus the pozzolanic reaction is considered to have a
positive impact on the long-term properties of the hardened concrete.
2. Effect of Sudanese Aggregate on Production of High Strength Concrete
DOI: 10.9790/1684-124598103 www.iosrjournals.org 99 | Page
This paper presents a part of an ongoing experimental laboratory investigation being carried out for
production and characterization of high strength concrete for heightening of Roseires Dam, which, located on
Blue Nile River in Sudan, was constructed in 1960s for power generation and irrigation purposes. It has been
decided to heighten this composite concrete buttress and earth fill dam by 10m to increase its storage capacity.
The raising works of Roseires concrete dam comprise the addition of mass concrete, reinforced
concrete, and post-tensioning requirements into both crest and the downstream portions of the dam. The
concrete dam section is divided into (11) typical structures along its 1km length. The total numbers were 69
buttresses. Because each structure has its specific geometry and function different design methodologies are
needed for each.
High Strength Concrete is a relatively recent development in concrete technology made possible by the
introduction of efficient water-reducing admixtures and high strength cementitious materials. This paper will
discuss the materials technology underlying the development of high strength concrete, influence of mixture
ingredients in the properties of both fresh and hardened high strength concrete; finally, the effect of components
in the cost will be studied. It is intended that this will lead to an understanding of the potential benefits and
limitations of high strength concrete, together with the expertise required to produce and use the material in a
practical and effective manner.
There is no “scientific” method for proportioning. This means that there is no chart that can be used to
derive the mixture ingredients to meet a specified level of performance. There are simply too many variables for
such a chart to be developed. Here are some general rules for proportioning: (2)
In the laboratory test and
production scale during mixture development, the process is too complex to predict what the outcome will be
without appropriate testing. Allow plenty of time for the necessary testing. (3)
The procedure described in the
ACI 211.4 was used. This procedure has evolved over many years and is the best recommendation currently
available. (4)
Mixture proportions for high-strength concrete typically contain 350 to 500 kg/m3
of cementitious
materials that may include 5 to 10% silica fume by mass. This concrete may have a w/cm as low as 0.20. Fly ash
may also be included in this concrete for either high-strength or high durability applications. (5)
Hence the
purpose of this paper was to study the effect of use of Sudanese aggregate with supplementary cementitious
materials, silica fume and fly ash in high strength concrete mixes, and study the effect of water- cementitious
materials ratio and concrete ingredients in compressive strength, workability and cost of high strength concrete.
Figure (1) Roseires Dam Concrete Section downstream view
II. Materials Used
2.1 Cement: In this research, a locally produced ordinary Portland cement type I, conforming to ASTM C150
(OPC 42.5N) (6)
which is extensively used in Sudan, was used in the trial batches production. The specific
gravity of cement used was 3.15, initial and final setting times were 2.2 and 3.6, other physical and
mechanical properties for cement are shown in Table (1).
Table (1) Physical and Mechanical Properties of Cement
Test according to BSEN196 Result
Normal Consistency 27.4%
Setting Time
Initial Setting Time 2.2 hour
Final Setting Time 3.6 hour
Loss on ignition 1.95%
Compressive Strength 2 days 32.1 MPa
28 days 60.7 MPa
3. Effect of Sudanese Aggregate on Production of High Strength Concrete
DOI: 10.9790/1684-124598103 www.iosrjournals.org 100 | Page
2.2 Aggregates
The coarse and fine aggregates used in this study were crushed marble processed from the local
quarries around Damazin City, the quarry for Roseires Dam Heightening Project. The maximum aggregate size
was 20 mm, The specific gravity and absorption of the coarse aggregates, determined in according with ASTM
C127 (7)
were 2.84 and 0.25respectively, whereas those of fine aggregates, determined in accordance with
ASTM C128 (8)
were 2.839 and 0.45 respectively. All the sand samples were tested for their absorption
percentage in saturated surface dry (SSD) condition. Organic impurities in sand were tested in accordance with
ASTM C-40. The water-cement ratio of all trial mixes were based on saturated surface dry condition (SSD) of
the aggregates, different type of aggregates from another quarry was used. To compare with marble, granite
aggregates from Merwei Dam (another recently constructed concrete dam in the north of Sudan) location were
used.
2.3 Chemical Admixtures (Superplasticizer)
The superplasticizer used in this study has the trade name of “PCA-(I)” from Jiangsu Bote new
Materials Company-China. PCA-(I) is a polycarboxylate polymer-basedcomposite admixture. It is a liquid
which has the performance of high range water reduction, excellent slump retention and strengthening. The
specific gravity of the superplasticizer was 1.085 and the PH was 8.11 with nil chloride content percentage by
weight. It is specially adapted for the production of high durability concrete, self-compacting concrete, high
compressive strength concrete, and high workability concrete. PCA-(I) superplasticizer is formulated to comply
with the ASTM specifications for concrete admixture: ASTM494, Type G (9)
.
2.4 Silica Fume
The Silica fume(SF ) used in this study was in accordance with the most international standards such
the European BS EN 13263 Silica fume for concrete, Part 1:2005 Definitions, requirements and conformity
criteria Part 2:2005 Conformity evaluation, and the American ASTM C1240-97b, Standard specification for
silica fume for use as a mineral admixture in hydraulic- cement concrete, mortar and grout.(10)
Table (2) Physical Properties of KD-12 Silica Fume
Test items
Specified limits according to ASTM
C12405, BS EN13263
Test Results
Absolute density (kg/m3
) ≥2200 2249
Loss on ignition (%) ≤3.5 1.88
Coarse particle ≤1.5 1.1
SiO2 (%) ≥86 92
Carbon content (%) ≤2.5 2.3
Moisture (%) ≤1 0.85
Specific area (m2
/g) ≥15 20
2.5 Fly ash
Fly ash used in this study was manufacture by Zouxian power plant-China. The properties of fly ash
are presented in Tables 3,4. ASTM C618; the requirement for Class F and Class C fly ashes, and the raw or
calcined natural pozzolans, Class N, for use in concrete. Fly ash properties may vary considerably in different
areas and from different sources within the same area. The preferred fly ashes for use in high strength concrete
have a loss on ignition not greater than 3 percent, have a high fineness, and come from a source with a
uniformity meeting ASTM C 618 requirements (11)
.
Table( 3) Chemical Properties of Fly Ash
Test items Specified limits according to BS 3892 Test Results
SO3 (%) Max.2.0% 1.68%
Chloride (%) Max.0.1% 0.03%
Calcium Oxide (%) Max.10% 8.4%
Table( 4) Physical Properties of Fly Ash
Test items Specified limits according to BS 3892 Test Results
Loss on ignition (%) Max.7.0% 1.39%
Moisture Content Max.0.5% 0.29%
Fineness Max.12% 8.24%
Particle Density Min.2000kg/m3
2039kg/m3
Water Requirement Max.95% (30%Fly Ash+70%Cement) 92%
Soundness Max.10mm 9.02mm
Strength Factor Min.0.8 0.83
4. Effect of Sudanese Aggregate on Production of High Strength Concrete
DOI: 10.9790/1684-124598103 www.iosrjournals.org 101 | Page
III. Experimental Programme
4.1 Slump Test:
After mixing, a portion of the fresh concrete was placed aside for plastic properties determination. Slump of
fresh concrete was measured according to ASTM C143. Precautions were taken to keep the slump between 150-
200 mm to obtain pumpable concrete for dam construction. (12)
4.2 Compressive Strength test:
Lime saturated-water curing method was used in this study. Concrete casting was performed according to BS
EN 12390-1:2000. (13)
Molds were covered to prevent loss of water from evaporation. Specimens were kept for
24 hours in molds at a temperature of about 23 C in casting room, and then cured for the specified time at
approximately 23 C ± 2 C. (14)
The specimens were tested in dry state for compressive strengths tests, in
accordance with BS EN 12390-3:2002. (15)
IV. Results
Table (5) presents the mix proportions for grade 80 (MPa), Concrete compressive strength, slump and
cost estimation for one meter cube. It can divided concrete strength to three different grades of high strength
concrete (80, 90, 100MPa), these are successfully produced using local Sudanese aggregates , silica fume and
silica fume with fly ash. w/cm ratios ranges between 0.19~0.3 utilized to produce the maximum values of
strength in the different grades of concrete. Silica fume and fly ash replacements in the range of 6.7 to 15% and
zero to 15% of cementunise materials respectively. Cement content between 390 and 560 Kg/m3
for the three
grades. In figure (2) by default, a 95% bivariate normal density ellipse is shown in each scatter-plot. The
narrowness of the ellipse shows the correlation of the variables. If the ellipse is fairly round and is not
diagonally oriented, the variables are uncorrelated. If the ellipse is narrow and diagonally oriented, the variables
are correlated.
Table (5) Concrete compressive strength, slump, concrete ingredients and cost estimation
Test No Date
Ave
Compressive
Strength
(Mpa) for
7days
Ave
Compressive
Strength
(Mpa) for
28days
Slump
mm
Aggregate
Types
W/Cm
Ratio
Cement
(kg/m3
)
Silica
Fumetype
KD-12
(kg/m3)
Fly Ash
(kg/m3)
Super
Plasticizer
type
PCA(1)
(kg/m3)
Water
(kg/m3)
Sand
(kg/m3)
Coarse
Aggregate
(kg/m3)
Cost of
m3$
1 30-Oct-09 75.0 81.2 190.0 marble 0.28 500 56 0 8.88 155 689 1023 166.4
2 31-Oct-09 62.7 80.0 182.0 marble 0.27 416 56 83 7.77 150 704 1003 165.3
3 6-Nov-09 69.8 80.9 190.0 marble 0.24 545 55 0 9.6 145 648 1042 174.4
4 11-Nov-09 79.3 91.1 205.0 marble 0.2 587 115 77 10.75 154 443 1057 253.5
5 14-Nov-09 79.0 87.6 195.0 marble 0.23 587 65 0 10.432 147 601 1045 192.2
6 5-Dec-09 88.1 96.4 188.0 marble 0.22 708 62 0 12.32 169 385 1191 213.2
7 6-Dec-09 77.3 97.7 216.0 marble 0.21 670 62 0 12.32 162 268 1231 205.4
8 7-Dec-09 92.3 86.3 207.0 marble 0.2 647 126 67 13.44 168 399 1050 275.1
9 7-Dec-09 92.2 91.7 215.0 marble 0.2 672 118 0 12.64 158 440 1025 259.1
10 13-Jan-10 65.6 80.3 220.0 granite 0.27 550 50 0 9.6 162 586 1022 170.0
11 14-Jan-10 68.5 83.7 230.0 granite 0.25 550 50 50 9.6 163 586 1022 179.5
12 15-Jan-10 80.4 91.5 165.0 granite 0.22 650 50 50 12 165 466 991 199.3
13 15-Jan-10 85.9 87.0 170.0 granite 0.23 600 50 50 11.2 161 499 1013 189.5
14 20-Jan-10 68.8 84.2 180 granite 0.3 495 55 0 9.6 165 615 1027 164.5
15 26-Jan-10 72.9 83.5 200.0 granite 0.23 595 70 35 11.9 161 498 1011 205.2
16 28-Jan-10 86.6 96.9 220.0 granite 0.22 660 90 0 12.75 165 467 992 230.2
17 29-Jan-10 91.5 105.2 170.0 granite 0.19 655 77 39 9.6 146 296 1184 222.0
18 29-Jan-10 80.2 88.2 200.0 granite 0.21 655 77 39 13.09 162 346 1095 224.4
19 8-Feb-10 81.7 88.5 143.0 granite 0.21 630 70 0 11.2 147 357 1195 204.9
20 11-Feb-10 81.8 95.3 155.0 granite 0.23 572 78 0 10.4 150 469 1149 201.4
21 15-Feb-10 91.9 100.6 162.0 granite 0.2 660 90 0 12 150 382 1145 230.1
22 17-Feb-10 98.2 104.7 161.0 granite 0.23 528 72 0 9.6 138 491 1202 187.2
23 19-Feb-10 98.7 109.2 121.0 granite 0.2 500 75 50 10 125 457 1235 194.5
24 19-Feb-10 94.7 100.4 134.0 granite 0.2 572 78 0 9.6 130 451 1218 201.1
25 21-Feb-10 88.6 96.9 159.0 granite 0.21 528 72 0 9.6 126 500 1225 187.4
26 24-Feb-10 92.9 106.1 116.0 granite 0.19 616 84 0 11.2 133 436 1180 216.0
27 25-Feb-10 88.4 104.3 215.0 granite 0.22 540 78 32 10.4 143 521 1106 201.5
28 28-Feb-10 101.0 110.6 77.0 granite 0.2 480 72 48 9.6 117 503 1233 187.5
29 1-Mar-10 81.3 94.5 205.0 granite 0.24 528 72 0 9.6 144 587 1091 187.2
30 21-Mar-10 87.1 97.9 185.0 granite 0.23 528 72 0 9.6 138 593 1101 187.3
31 31-Mar-10 90.7 103.6 115.0 marble 0.23 484 66 0 8.8 124 551 1225 173.1
32 14-Apr-10 93.4 102.4 125.0 marble 0.22 585 65 0 10.4 140 641 1190 193.0
33 25-Apr-10 94.1 102.8 145.0 marble 0.22 575 50 0 10 138 662 1177 176.6
5. Effect of Sudanese Aggregate on Production of High Strength Concrete
DOI: 10.9790/1684-124598103 www.iosrjournals.org 102 | Page
Figure (2) Multivariate relationship between compressive strength 28 days (MPa), compressive strength 7 days
(MPa) and Cost with all mixture compounds.
6. Effect of Sudanese Aggregate on Production of High Strength Concrete
DOI: 10.9790/1684-124598103 www.iosrjournals.org 103 | Page
V. Conclusions
On the basis of test results the following major conclusions can be drawn:
1. The present study shows that the maximum values of compressive strength for different grades were
obtained at water-cementitious materials ratios between 0.19 and 0.3.
2. The relationship between 28 days compressive strength and w/cm ratio is strong inverse relationship, when
one quantity increases the other decreases. For example, when w/cm ratio is increased, the compressive
strength decreases.
3. The relationship between 28 days compressive strength and Silica fume type KD-12 is direct relationship
both physical quantities may increase or decrease simultaneously.
4. The relationship between 28 days compressive strength and fly ash type (F) is inverse relationship.
5. There is no effect in the relationship between 28 days compressive strength and Super-plasticizer type PCA
(1).
6. The relationship between 28 days compressive strength and fine aggregate is inverse relationship.
7. The relationship between28 days compressive strength and Coarse aggregate is strong direct relationship.
That means the local coarse aggregate is main factor in producing high strength concrete.
8. The relationship between 28 days compressive strength and 7 days compressive strength is strong direct
relationship.
9. The results of the present investigation indicated that the maximum compressive strength occurred at about
6.7 to 15% Silica fume content.
10. The relationship between28 days compressive strength and cost is direct relationship.
11. Silica fume and Super-plasticizer type PCA (1) had strong influence in cost.
12. Water- cementitious materials ratio had positive effect in slump.
13. Coarse aggregate had strong negative effect in slump.
Acknowledgements
I would like to thank SMEC International Company for their cooperation during the part of the
experimental testing program of this research. Also I would like to thank the Dams Implementation Unit (DIU)
of Sudan for allowing the authors to use the information and photographs needed in this research paper.
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