This document summarizes the results of a study investigating the effects of ultra-fine materials on the workability and strength of concrete containing alkali-activated slag as the binder. It was found that:
1) Partial replacement of slag with ultra-fine fly ash improved workability but had similar strength development as ordinary portland cement concrete.
2) Partial replacement with condensed silica fume or ultra-fine slag showed significantly greater strength than alkali-activated slag concrete at ages greater than one day, though condensed silica fume reduced workability.
3) Of the mixes tested, concrete with partial replacement of slag with condensed silica fume achieved the highest compressive strength over 91 days of
International Journal of Engineering Research and DevelopmentIJERD Editor
The document investigates the effects of silica fume and fly ash on the flexural strength of roller compacted concrete. Tests found that using fly ash alone decreased 28-day flexural strength while silica fume alone slightly increased it. However, using silica fume and fly ash together resulted in higher flexural strength than either additive alone or the control mixture. The maximum 28-day flexural strength of 4.53 MPa was achieved with a mixture of 85% OPC, 10% fly ash, and 5% silica fume.
This document summarizes a study on the effects of using saturated porous blast furnace slag coarse aggregate in alkali-activated slag concrete (AAS). The study found that AAS containing the porous coarse aggregate had higher compressive strength and significantly less drying shrinkage compared to AAS made with normal weight coarse aggregate. The porous aggregate provided internal curing, with water slowly releasing inside the concrete to further hydrate the paste. Under drying conditions, AAS with porous aggregate showed 40% less shrinkage and higher strengths after 1 day compared to AAS with normal aggregate.
Study the effect of addition of wast plastic on compressive and tensileIAEME Publication
This document summarizes a study on the effect of adding waste plastic at percentages of 0.5%, 1%, and 1.5% by volume on the compressive and tensile strengths of structural lightweight concrete containing crushed bricks as coarse aggregate. Tests were performed on fresh and hardened concrete including unit weight, compressive strength, splitting tensile strength, and flexural strength. The results showed that waste plastic addition had a more pronounced effect on tensile strength than compressive strength of the lightweight concrete. The maximum increases in compressive, splitting tensile, and flexural strengths at 28 days were 4.4%, 29%, and 40.8% respectively for concrete with 1% waste plastic addition.
ENHANCEMENT OF SEISMIC PERFORMANCE OF STRUCTURES USING HyFRCIEI GSC
Presentation on ENHANCEMENT OF SEISMIC PERFORMANCE OF STRUCTURES USING HyFRC by Needhi Kotoky Under the supervision of Dr. Anjan Dutta and Dr. Sajal K. Deb Department of Civil EngineeringIndian Institute of Technology Guwahati
This document describes the development of a numerical model to analyze the cracking behavior of alkali-activated slag concrete (AASC) beams subjected to restrained shrinkage. The model accounts for the time-dependent properties of different concrete mixtures, including shrinkage, elastic modulus, creep, and tensile strength. Experimental data on these properties was used to develop time-dependent relationships in the model. The model aims to better understand the contributions of these parameters to cracking risk by comparing model results to experimental cracking data from restrained beam tests of various concrete mixtures.
This paper presents part of the results of an ongoing laboratory study carried out to study on
strength and durability characteristics of ternary concrete made with and without ternary mixtures of
cement-fly ash- silica fume. In the present work an attempt has been made to study the strength
properties of ternary concrete in compression, tension and flexure and also durability aspects of
ternary blended concrete. In the investigation, M25 Grade concrete mix is designed with different
percentages of cementitious materials (5%, 7.5%, 10% & 12.5%) and tests are conducted for
compressive strength, split tensile strength and flexure strengths at 7, 28 and 56 days. Test results
indicate that the replacement of cement by 10% had attained a maximum strength in M25 Grade
concrete. The results obtained thus are encouraging for partial replacement.
In this study, fourteen reinforced concrete beams were tested to investigate the shear behavior of lightweight fiber reinforced concrete beams. Lightweight Expanded Clay Aggregate (LECA) was used as a partial and full replacement to the normal weight aggregate. The experimental program included three lightweight concrete beams with partial replacement of aggregate, nine lightweight concrete beams with full replacement of aggregate, and two normal weight control beams. In each group one beam was cast using steel fiber concrete, one with polypropylene fiber concrete, and one without fibers. The effects of parameters such as weight of concrete, type of fibers, area of stirrups, and shear span to depth ratio (a/d) on the beams behavior are presented. The response of the tested beams is analyzed in terms of mode of failure, deflection, strain, cracking load, and ultimatecapacity. The test results are compared to those estimated from different design codes for lightweight concrete structures.
International Journal of Engineering Research and DevelopmentIJERD Editor
The document investigates the effects of silica fume and fly ash on the flexural strength of roller compacted concrete. Tests found that using fly ash alone decreased 28-day flexural strength while silica fume alone slightly increased it. However, using silica fume and fly ash together resulted in higher flexural strength than either additive alone or the control mixture. The maximum 28-day flexural strength of 4.53 MPa was achieved with a mixture of 85% OPC, 10% fly ash, and 5% silica fume.
This document summarizes a study on the effects of using saturated porous blast furnace slag coarse aggregate in alkali-activated slag concrete (AAS). The study found that AAS containing the porous coarse aggregate had higher compressive strength and significantly less drying shrinkage compared to AAS made with normal weight coarse aggregate. The porous aggregate provided internal curing, with water slowly releasing inside the concrete to further hydrate the paste. Under drying conditions, AAS with porous aggregate showed 40% less shrinkage and higher strengths after 1 day compared to AAS with normal aggregate.
Study the effect of addition of wast plastic on compressive and tensileIAEME Publication
This document summarizes a study on the effect of adding waste plastic at percentages of 0.5%, 1%, and 1.5% by volume on the compressive and tensile strengths of structural lightweight concrete containing crushed bricks as coarse aggregate. Tests were performed on fresh and hardened concrete including unit weight, compressive strength, splitting tensile strength, and flexural strength. The results showed that waste plastic addition had a more pronounced effect on tensile strength than compressive strength of the lightweight concrete. The maximum increases in compressive, splitting tensile, and flexural strengths at 28 days were 4.4%, 29%, and 40.8% respectively for concrete with 1% waste plastic addition.
ENHANCEMENT OF SEISMIC PERFORMANCE OF STRUCTURES USING HyFRCIEI GSC
Presentation on ENHANCEMENT OF SEISMIC PERFORMANCE OF STRUCTURES USING HyFRC by Needhi Kotoky Under the supervision of Dr. Anjan Dutta and Dr. Sajal K. Deb Department of Civil EngineeringIndian Institute of Technology Guwahati
This document describes the development of a numerical model to analyze the cracking behavior of alkali-activated slag concrete (AASC) beams subjected to restrained shrinkage. The model accounts for the time-dependent properties of different concrete mixtures, including shrinkage, elastic modulus, creep, and tensile strength. Experimental data on these properties was used to develop time-dependent relationships in the model. The model aims to better understand the contributions of these parameters to cracking risk by comparing model results to experimental cracking data from restrained beam tests of various concrete mixtures.
This paper presents part of the results of an ongoing laboratory study carried out to study on
strength and durability characteristics of ternary concrete made with and without ternary mixtures of
cement-fly ash- silica fume. In the present work an attempt has been made to study the strength
properties of ternary concrete in compression, tension and flexure and also durability aspects of
ternary blended concrete. In the investigation, M25 Grade concrete mix is designed with different
percentages of cementitious materials (5%, 7.5%, 10% & 12.5%) and tests are conducted for
compressive strength, split tensile strength and flexure strengths at 7, 28 and 56 days. Test results
indicate that the replacement of cement by 10% had attained a maximum strength in M25 Grade
concrete. The results obtained thus are encouraging for partial replacement.
In this study, fourteen reinforced concrete beams were tested to investigate the shear behavior of lightweight fiber reinforced concrete beams. Lightweight Expanded Clay Aggregate (LECA) was used as a partial and full replacement to the normal weight aggregate. The experimental program included three lightweight concrete beams with partial replacement of aggregate, nine lightweight concrete beams with full replacement of aggregate, and two normal weight control beams. In each group one beam was cast using steel fiber concrete, one with polypropylene fiber concrete, and one without fibers. The effects of parameters such as weight of concrete, type of fibers, area of stirrups, and shear span to depth ratio (a/d) on the beams behavior are presented. The response of the tested beams is analyzed in terms of mode of failure, deflection, strain, cracking load, and ultimatecapacity. The test results are compared to those estimated from different design codes for lightweight concrete structures.
Ultimate Behavior of Lightweight High Strength Concrete Filled Steel Tube (LW...IOSR Journals
This document summarizes research on the ultimate behavior of lightweight high strength concrete filled steel tube (LWHCFST) bridges. The researchers conducted compression tests on LWHCFST cylinders to determine the concrete's strength and modulus of elasticity. They then used finite element analysis to model an example arch bridge made with hollow steel tubes, normal strength concrete filled steel tubes, and LWHCFST. The analysis found that the bridge failed under the highest load when made with LWHCFST, indicating it can support longer spans than alternatives while maintaining strength. In conclusion, LWHCFST is beneficial for bridge design by reducing weight without compromising load capacity.
Experimental study of effects of potassium carbonate on strength parameters o...IAEME Publication
This study examines the effects of potassium carbonate (K2CO3) on the strength properties of plain concrete. Concrete specimens were produced with K2CO3 added at different percentages by weight of cement (2%, 2.2%, 2.4%, 2.6%, and 3%). The specimens were tested for compressive, flexural, and split tensile strengths at various ages. Results showed strengths increased up to 2.6% K2CO3 addition, but decreased with 3% addition. The optimum K2CO3 percentage was found to be 2.6%, as it improved strengths without harming concrete properties.
An experimental investigation was conducted to investigate the behavior of ultra-high strength reactive concrete (RPC) columns before and after strengthening with carbon fiber reinforced polymer (CFRP) sheets jacketing under eccentric axi al load. Twelve columns were tested up to failure, strengthened and retested to examine strengthening efficiency and to evaluate the effects of variation of the concrete type (normal or RPC), presence of steel fibers and main steel reinforcement ratio. Experimental results showed that CFRP jacketing increases the ultimate failure load of strengthened columns up to 185%, highly stiffens them (reduces lateral displacements) and allow more ductile failure than the original columns. Also, inclusion of steel fibers in RPC columns increases failure loads up to 86%, prevents palling of the concrete cover and increase the ductility.
Cracking tendency of alkali-activated slag concretefrank collins
This document summarizes a study on the cracking tendency of alkali-activated slag concrete (AASC) when subjected to restrained shrinkage. Key findings include:
1) AASC has higher drying shrinkage than ordinary Portland cement concrete (OPCC) which can lead to greater cracking under restrained conditions.
2) In restrained ring tests, AASC cracked within 7 days while OPCC took 168 days to crack, showing AASC has a higher cracking tendency.
3) To better evaluate cracking, researchers developed a restrained beam test where embedded steel rods or a stress magnifier plate provided restraint. Beams with AASC cracked within hours while OPCC took 9 days, further demonstrating the higher
This document summarizes research on the tensile characteristics of no aggregate concrete. Testing found that no aggregate concrete has lower tensile strength than normal concrete, around 5-6% of its compressive strength compared to 10% for normal concrete. Replacing some fly ash with cement can increase tensile strength of no aggregate concrete. Density is also lower than normal concrete and decreases over time. The elastic modulus of no aggregate concrete is around 11 GPa compared to 26 GPa for normal concrete, and it exhibits more brittleness. Increasing cement content or decreasing fly ash content can respectively increase or decrease tensile strength. While no aggregate concrete has benefits, full replacement of aggregates is not recommended.
This study evaluated the influence of mineral admixtures (fly ash and GGBS) on the properties of concrete mixtures containing chemical admixtures. Concrete mixtures were prepared by replacing cement with 15-45% fly ash or 40-60% GGBS. Compressive, split tensile, and flexural strength tests were performed on specimens cured for 3, 7, and 28 days. Results showed that replacing 15% of cement with fly ash or 50% with GGBS improved workability and increased compressive strength by over 5% and 7% respectively at 28 days compared to a control mixture. Replacing cement with mineral admixtures also improved split tensile and flexural strengths. The optimum replacements were found
This study evaluated the effect of calcium nitrite as a corrosion inhibitor in quarry dust concrete. Concrete cubes, beams, and cylinders were cast with 0-4% calcium nitrite additions. Strength tests at 3, 7, and 28 days showed maximum improvements of 8.75% in compression, 5.26% in splitting tension, and 3.53% in flexure at 2% calcium nitrite. Impressed voltage and rapid chloride permeability tests indicated corrosion initiation was delayed up to 288 hours and permeability decreased up to 97.87% at 2% addition. Weight loss measurements also showed maximum corrosion resistance at 2% calcium nitrite. The study demonstrated that quarry dust concrete with 2% calcium nitrite exhibited improved strength and
Drying shrinkage behaviour of structural lightweight aggregate concrete conta...University of Malaya
This document summarizes a study that investigated reducing the drying shrinkage of structural lightweight concrete containing oil palm bio-products. The study partially replaced oil palm shell aggregate with oil-palm-boiler clinker aggregate in two sets of concrete mixes. Testing found that partial substitutions of 30-50% significantly reduced the long-term drying shrinkage of the concrete. Lower water-cement ratios and air drying curing conditions also reduced shrinkage compared to moist curing. The results indicate that partial replacement of oil palm shell with oil-palm-boiler clinker can effectively decrease the drying shrinkage of this type of lightweight concrete.
THEORETICAL BEHAVIOR OF COMPOSITE CONSTRUCTION PRECAST REACTIVE POWDER RC GIR...IAEME Publication
This study displays numerically (or theoretically) investigation by using the finite element models for experimental work of composite behavior for hybrid reinforced concrete slab on girder from locale material in Iraq, ordinary concrete in slab and reactive powder concrete in girder, RPC, with steel fibers of different types (straight, hook, and mix between its), tested as simply supported span subjected under two point loading. Which ANSYS version 15.0 is utilized. By studying the compatibility between the experimental results and the theoretical results. As well as, parametric study of many others variables are investigated by using ANSYS (version 15.0), such as: changing the compressive strength of the slab, changing the main reinforcement of the girder, and changing thickness of resin bond layer between girder and slab.
Saqib Imran provides notes on civil engineering lab tests, including procedures for performing a California Bearing Ratio test and an Unconfined Compression test. The document outlines the apparatus, test procedures, observations, calculations, and significance of the CBR test. It also summarizes the purpose, standard reference, equipment, test procedure, and analysis for the Unconfined Compression test. Finally, it provides the procedure to determine the shrinkage limit of a soil sample.
Study on Strength of Fly Ash Based Geopolymer Concrete Under Heat Curingijsrd.com
fly ash is a noncombustible material obtained from the various thermal power plants. Since fly ash is available in large scale, it is disposed of in rivers and landfills and ponds by thermal industries which are posing danger to environment. Due to high pozzolanic activity of fly ash, efforts are being made to use it as a cement replacement material. GeoPolymer concrete makes 100 percent utilization of fly ash in concrete along with alkaline solutions, as a binder. The cube specimens and beams are casted for 2% and 4% super plasticizers and alkaline to fly ash ratio of 0.35. The compressive strength of cubes is compared to that of conventional cubes at 7, 14 and 28 days .it is observed that GeoPolymer concrete is economical as compared to normal concrete from compressive strength point of view.
Experimental Study Compared With American Code - ConcreteFilled – Double Skin...ijceronline
Six Specimens with three different volume fractions of steel fibers are cast and tested. Experiments on circular steel tubes in – filled with steel fiber reinforced concrete (SFRC) and normal concrete have been performed to investigate the contribution of steel fibers to the load bearing capacity of Short Composite Columns . The main variable considered in the test study is the percentage of steel. Fibers added to the in –filled concrete. All the specimens were tested under axial failure state realization. This project presents the percentage Variation in the compression strengths of the 3 types of Composite members taken under Study. The results show that 1.5% SFRC in filled steel columns exhibit enhanced ultimate load carrying compression until capacity. Experimental studies compared with American code
Research Summary: How Pumice Pozzolan Improves Concrete Strength and DurabilityHess Pumice Products
A landmark research study done by the University of Utah details how pumice pozzolans improve concrete strength and durability by mitigating or eliminating the problems that plague standard concrete. Adding natural pumice pozzolan to the concrete mix design ignites a pozzolanic reaction in the curing concrete that defeats deleterious effects like heat of hydration cracking, sulfate and chloride attacks, freeze-thaw spalling, alkali silica reaction (ASR), and efflorescence. Long-term compressive strength is increased anywhere from 10 to 40 percent.
This document discusses the fatigue behavior of high volume fly ash concrete (HVFAC) under constant amplitude and compound loading. It presents test results of 95 HVFAC and 100 conventional concrete prism specimens tested under constant amplitude flexural fatigue loading. It also discusses test results of 24 HVFAC specimens under compound fatigue loading to verify the validity of Miner's hypothesis for HVFAC. Probability distributions were developed from the fatigue life test results and S-N curves were established relating stress level to fatigue life for both concretes. The findings provide useful data on fatigue performance of HVFAC.
Effect of Ground Granulated Blast Furnace Slag as Partial Cement Replacement ...IRJET Journal
This document reviews the use of ground granulated blast furnace slag (GGBFS) as a partial replacement for cement in concrete. It discusses how GGBFS can reduce the environmental impact of concrete production by lowering carbon dioxide emissions compared to ordinary Portland cement. The literature review summarizes several studies that investigated how replacing cement with GGBFS affects the properties of concrete, including increased workability, compressive strength, tensile strength, acid resistance, and sulfate resistance. Replacing up to 50% of cement with GGBFS was found to improve concrete properties and durability while also reducing costs. Using GGBFS thus provides environmental, economic and performance benefits for concrete.
Effect of sulfate on the properties of self compacting concrete 2IAEME Publication
This document summarizes a study that investigated the effect of internal sulfates on the properties of self-compacting concrete reinforced with steel fibers. Fifteen concrete mixes were tested with varying steel fiber contents (0, 0.75, 1.5% by volume) and SO3 levels (3.9, 5, 6, 7, 8% by weight of cement). Tests were performed on the fresh and hardened properties of the concrete. The results showed that increasing sulfates decreased flowability and passing ability while increasing setting time. However, hardened properties of fiber-reinforced self-compacting concrete showed similar or better sulfate resistance compared to plain self-compacting concrete, with resistance increasing at higher fiber contents. The study concluded
IRJET- Experimental Investigation on Concrete by Partial Replacement of Coars...IRJET Journal
This document presents the results of an experimental study investigating the effects of partially replacing coarse aggregate with cinder in concrete. M30 concrete mixes were designed using the ISI method. Cubes and cylinders were cast with 0%, 20%, 40%, 60%, 80%, and 100% replacement of coarse aggregate with cinder and tested for compressive strength, split tensile strength, and flexural strength at 7 and 28 days. The results showed that compressive strength, split tensile strength, and flexural strength generally decreased as the cinder replacement ratio increased. The highest strengths were obtained with 40-60% cinder replacement. Overall, partially replacing coarse aggregate with cinder produced lightweight concrete with reasonably good strength.
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.
The document discusses how hazardous air pollution control residue can be transformed into a non-hazardous glass material called Plasmarok through plasma technology. Plasmarok can then be used as a cement replacement to create alkali-activated concretes with high compressive strengths over 90 MPa. The properties of these concretes depend on factors like the particle size, chemical composition, and processing method of Plasmarok. Reducing the particle size and increasing the silicon-to-aluminum ratio can improve the strength. Understanding these influencing factors helps develop consistent concrete materials with desirable properties.
This document discusses how the pore size distribution affects drying shrinkage in alkali-activated slag concrete (AASC) compared to ordinary Portland cement concrete (OPCC). The main points are:
1) AASC exhibited higher drying shrinkage than OPCC even though OPCC lost more moisture during drying.
2) The pore size distribution of AASC pastes showed a much higher proportion of pores in the mesopore region compared to OPC pastes.
3) The radius of pores where the meniscus forms during drying seems to be a more important factor for shrinkage than the total moisture loss. This supports the theory that capillary tensile forces from drying cause shrinkage.
The document describes research into developing alkali-activated slag concrete (AASC) for construction use that achieves high early strength. The researchers created a dry powdered activator by blending sodium silicate and hydrated lime that could be pre-blended with slag. When used to make AASC, this resulted in minimal slump loss over time and compressive strengths similar to ordinary Portland cement concrete at one day. However, AASC exhibited higher drying shrinkage than OPCC. Various methods were investigated to reduce the shrinkage of AASC, such as curing regimes and use of shrinkage-reducing admixtures or porous aggregate, with some success in lowering crack tendency and widths.
This document discusses microcracking and strength development in alkali activated slag concrete (AASC) subjected to different curing regimes. The main points are:
1) AASC cured without moist curing ("exposed") exhibited higher levels of microcracking compared to AASC with moist curing ("bath" or "sealed"), as measured by surface crack detection, water sorptivity, and mercury intrusion porosimetry tests.
2) Exposed AASC also showed significantly reduced compressive strength development compared to bath or sealed cured AASC. Strength of exposed AASC was 54% and 41% lower than bath and sealed AASC at 365 days.
3) Microcracking in
Ultimate Behavior of Lightweight High Strength Concrete Filled Steel Tube (LW...IOSR Journals
This document summarizes research on the ultimate behavior of lightweight high strength concrete filled steel tube (LWHCFST) bridges. The researchers conducted compression tests on LWHCFST cylinders to determine the concrete's strength and modulus of elasticity. They then used finite element analysis to model an example arch bridge made with hollow steel tubes, normal strength concrete filled steel tubes, and LWHCFST. The analysis found that the bridge failed under the highest load when made with LWHCFST, indicating it can support longer spans than alternatives while maintaining strength. In conclusion, LWHCFST is beneficial for bridge design by reducing weight without compromising load capacity.
Experimental study of effects of potassium carbonate on strength parameters o...IAEME Publication
This study examines the effects of potassium carbonate (K2CO3) on the strength properties of plain concrete. Concrete specimens were produced with K2CO3 added at different percentages by weight of cement (2%, 2.2%, 2.4%, 2.6%, and 3%). The specimens were tested for compressive, flexural, and split tensile strengths at various ages. Results showed strengths increased up to 2.6% K2CO3 addition, but decreased with 3% addition. The optimum K2CO3 percentage was found to be 2.6%, as it improved strengths without harming concrete properties.
An experimental investigation was conducted to investigate the behavior of ultra-high strength reactive concrete (RPC) columns before and after strengthening with carbon fiber reinforced polymer (CFRP) sheets jacketing under eccentric axi al load. Twelve columns were tested up to failure, strengthened and retested to examine strengthening efficiency and to evaluate the effects of variation of the concrete type (normal or RPC), presence of steel fibers and main steel reinforcement ratio. Experimental results showed that CFRP jacketing increases the ultimate failure load of strengthened columns up to 185%, highly stiffens them (reduces lateral displacements) and allow more ductile failure than the original columns. Also, inclusion of steel fibers in RPC columns increases failure loads up to 86%, prevents palling of the concrete cover and increase the ductility.
Cracking tendency of alkali-activated slag concretefrank collins
This document summarizes a study on the cracking tendency of alkali-activated slag concrete (AASC) when subjected to restrained shrinkage. Key findings include:
1) AASC has higher drying shrinkage than ordinary Portland cement concrete (OPCC) which can lead to greater cracking under restrained conditions.
2) In restrained ring tests, AASC cracked within 7 days while OPCC took 168 days to crack, showing AASC has a higher cracking tendency.
3) To better evaluate cracking, researchers developed a restrained beam test where embedded steel rods or a stress magnifier plate provided restraint. Beams with AASC cracked within hours while OPCC took 9 days, further demonstrating the higher
This document summarizes research on the tensile characteristics of no aggregate concrete. Testing found that no aggregate concrete has lower tensile strength than normal concrete, around 5-6% of its compressive strength compared to 10% for normal concrete. Replacing some fly ash with cement can increase tensile strength of no aggregate concrete. Density is also lower than normal concrete and decreases over time. The elastic modulus of no aggregate concrete is around 11 GPa compared to 26 GPa for normal concrete, and it exhibits more brittleness. Increasing cement content or decreasing fly ash content can respectively increase or decrease tensile strength. While no aggregate concrete has benefits, full replacement of aggregates is not recommended.
This study evaluated the influence of mineral admixtures (fly ash and GGBS) on the properties of concrete mixtures containing chemical admixtures. Concrete mixtures were prepared by replacing cement with 15-45% fly ash or 40-60% GGBS. Compressive, split tensile, and flexural strength tests were performed on specimens cured for 3, 7, and 28 days. Results showed that replacing 15% of cement with fly ash or 50% with GGBS improved workability and increased compressive strength by over 5% and 7% respectively at 28 days compared to a control mixture. Replacing cement with mineral admixtures also improved split tensile and flexural strengths. The optimum replacements were found
This study evaluated the effect of calcium nitrite as a corrosion inhibitor in quarry dust concrete. Concrete cubes, beams, and cylinders were cast with 0-4% calcium nitrite additions. Strength tests at 3, 7, and 28 days showed maximum improvements of 8.75% in compression, 5.26% in splitting tension, and 3.53% in flexure at 2% calcium nitrite. Impressed voltage and rapid chloride permeability tests indicated corrosion initiation was delayed up to 288 hours and permeability decreased up to 97.87% at 2% addition. Weight loss measurements also showed maximum corrosion resistance at 2% calcium nitrite. The study demonstrated that quarry dust concrete with 2% calcium nitrite exhibited improved strength and
Drying shrinkage behaviour of structural lightweight aggregate concrete conta...University of Malaya
This document summarizes a study that investigated reducing the drying shrinkage of structural lightweight concrete containing oil palm bio-products. The study partially replaced oil palm shell aggregate with oil-palm-boiler clinker aggregate in two sets of concrete mixes. Testing found that partial substitutions of 30-50% significantly reduced the long-term drying shrinkage of the concrete. Lower water-cement ratios and air drying curing conditions also reduced shrinkage compared to moist curing. The results indicate that partial replacement of oil palm shell with oil-palm-boiler clinker can effectively decrease the drying shrinkage of this type of lightweight concrete.
THEORETICAL BEHAVIOR OF COMPOSITE CONSTRUCTION PRECAST REACTIVE POWDER RC GIR...IAEME Publication
This study displays numerically (or theoretically) investigation by using the finite element models for experimental work of composite behavior for hybrid reinforced concrete slab on girder from locale material in Iraq, ordinary concrete in slab and reactive powder concrete in girder, RPC, with steel fibers of different types (straight, hook, and mix between its), tested as simply supported span subjected under two point loading. Which ANSYS version 15.0 is utilized. By studying the compatibility between the experimental results and the theoretical results. As well as, parametric study of many others variables are investigated by using ANSYS (version 15.0), such as: changing the compressive strength of the slab, changing the main reinforcement of the girder, and changing thickness of resin bond layer between girder and slab.
Saqib Imran provides notes on civil engineering lab tests, including procedures for performing a California Bearing Ratio test and an Unconfined Compression test. The document outlines the apparatus, test procedures, observations, calculations, and significance of the CBR test. It also summarizes the purpose, standard reference, equipment, test procedure, and analysis for the Unconfined Compression test. Finally, it provides the procedure to determine the shrinkage limit of a soil sample.
Study on Strength of Fly Ash Based Geopolymer Concrete Under Heat Curingijsrd.com
fly ash is a noncombustible material obtained from the various thermal power plants. Since fly ash is available in large scale, it is disposed of in rivers and landfills and ponds by thermal industries which are posing danger to environment. Due to high pozzolanic activity of fly ash, efforts are being made to use it as a cement replacement material. GeoPolymer concrete makes 100 percent utilization of fly ash in concrete along with alkaline solutions, as a binder. The cube specimens and beams are casted for 2% and 4% super plasticizers and alkaline to fly ash ratio of 0.35. The compressive strength of cubes is compared to that of conventional cubes at 7, 14 and 28 days .it is observed that GeoPolymer concrete is economical as compared to normal concrete from compressive strength point of view.
Experimental Study Compared With American Code - ConcreteFilled – Double Skin...ijceronline
Six Specimens with three different volume fractions of steel fibers are cast and tested. Experiments on circular steel tubes in – filled with steel fiber reinforced concrete (SFRC) and normal concrete have been performed to investigate the contribution of steel fibers to the load bearing capacity of Short Composite Columns . The main variable considered in the test study is the percentage of steel. Fibers added to the in –filled concrete. All the specimens were tested under axial failure state realization. This project presents the percentage Variation in the compression strengths of the 3 types of Composite members taken under Study. The results show that 1.5% SFRC in filled steel columns exhibit enhanced ultimate load carrying compression until capacity. Experimental studies compared with American code
Research Summary: How Pumice Pozzolan Improves Concrete Strength and DurabilityHess Pumice Products
A landmark research study done by the University of Utah details how pumice pozzolans improve concrete strength and durability by mitigating or eliminating the problems that plague standard concrete. Adding natural pumice pozzolan to the concrete mix design ignites a pozzolanic reaction in the curing concrete that defeats deleterious effects like heat of hydration cracking, sulfate and chloride attacks, freeze-thaw spalling, alkali silica reaction (ASR), and efflorescence. Long-term compressive strength is increased anywhere from 10 to 40 percent.
This document discusses the fatigue behavior of high volume fly ash concrete (HVFAC) under constant amplitude and compound loading. It presents test results of 95 HVFAC and 100 conventional concrete prism specimens tested under constant amplitude flexural fatigue loading. It also discusses test results of 24 HVFAC specimens under compound fatigue loading to verify the validity of Miner's hypothesis for HVFAC. Probability distributions were developed from the fatigue life test results and S-N curves were established relating stress level to fatigue life for both concretes. The findings provide useful data on fatigue performance of HVFAC.
Effect of Ground Granulated Blast Furnace Slag as Partial Cement Replacement ...IRJET Journal
This document reviews the use of ground granulated blast furnace slag (GGBFS) as a partial replacement for cement in concrete. It discusses how GGBFS can reduce the environmental impact of concrete production by lowering carbon dioxide emissions compared to ordinary Portland cement. The literature review summarizes several studies that investigated how replacing cement with GGBFS affects the properties of concrete, including increased workability, compressive strength, tensile strength, acid resistance, and sulfate resistance. Replacing up to 50% of cement with GGBFS was found to improve concrete properties and durability while also reducing costs. Using GGBFS thus provides environmental, economic and performance benefits for concrete.
Effect of sulfate on the properties of self compacting concrete 2IAEME Publication
This document summarizes a study that investigated the effect of internal sulfates on the properties of self-compacting concrete reinforced with steel fibers. Fifteen concrete mixes were tested with varying steel fiber contents (0, 0.75, 1.5% by volume) and SO3 levels (3.9, 5, 6, 7, 8% by weight of cement). Tests were performed on the fresh and hardened properties of the concrete. The results showed that increasing sulfates decreased flowability and passing ability while increasing setting time. However, hardened properties of fiber-reinforced self-compacting concrete showed similar or better sulfate resistance compared to plain self-compacting concrete, with resistance increasing at higher fiber contents. The study concluded
IRJET- Experimental Investigation on Concrete by Partial Replacement of Coars...IRJET Journal
This document presents the results of an experimental study investigating the effects of partially replacing coarse aggregate with cinder in concrete. M30 concrete mixes were designed using the ISI method. Cubes and cylinders were cast with 0%, 20%, 40%, 60%, 80%, and 100% replacement of coarse aggregate with cinder and tested for compressive strength, split tensile strength, and flexural strength at 7 and 28 days. The results showed that compressive strength, split tensile strength, and flexural strength generally decreased as the cinder replacement ratio increased. The highest strengths were obtained with 40-60% cinder replacement. Overall, partially replacing coarse aggregate with cinder produced lightweight concrete with reasonably good strength.
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.
The document discusses how hazardous air pollution control residue can be transformed into a non-hazardous glass material called Plasmarok through plasma technology. Plasmarok can then be used as a cement replacement to create alkali-activated concretes with high compressive strengths over 90 MPa. The properties of these concretes depend on factors like the particle size, chemical composition, and processing method of Plasmarok. Reducing the particle size and increasing the silicon-to-aluminum ratio can improve the strength. Understanding these influencing factors helps develop consistent concrete materials with desirable properties.
This document discusses how the pore size distribution affects drying shrinkage in alkali-activated slag concrete (AASC) compared to ordinary Portland cement concrete (OPCC). The main points are:
1) AASC exhibited higher drying shrinkage than OPCC even though OPCC lost more moisture during drying.
2) The pore size distribution of AASC pastes showed a much higher proportion of pores in the mesopore region compared to OPC pastes.
3) The radius of pores where the meniscus forms during drying seems to be a more important factor for shrinkage than the total moisture loss. This supports the theory that capillary tensile forces from drying cause shrinkage.
The document describes research into developing alkali-activated slag concrete (AASC) for construction use that achieves high early strength. The researchers created a dry powdered activator by blending sodium silicate and hydrated lime that could be pre-blended with slag. When used to make AASC, this resulted in minimal slump loss over time and compressive strengths similar to ordinary Portland cement concrete at one day. However, AASC exhibited higher drying shrinkage than OPCC. Various methods were investigated to reduce the shrinkage of AASC, such as curing regimes and use of shrinkage-reducing admixtures or porous aggregate, with some success in lowering crack tendency and widths.
This document discusses microcracking and strength development in alkali activated slag concrete (AASC) subjected to different curing regimes. The main points are:
1) AASC cured without moist curing ("exposed") exhibited higher levels of microcracking compared to AASC with moist curing ("bath" or "sealed"), as measured by surface crack detection, water sorptivity, and mercury intrusion porosimetry tests.
2) Exposed AASC also showed significantly reduced compressive strength development compared to bath or sealed cured AASC. Strength of exposed AASC was 54% and 41% lower than bath and sealed AASC at 365 days.
3) Microcracking in
This paper investigates the workability and mechanical properties of concrete containing alkali-activated slag as the binder. Two types of activators were used: sodium hydroxide with sodium carbonate, and sodium silicate with hydrated lime. The fresh and hardened concrete properties of these alkali-activated slag concretes were compared to ordinary portland cement concrete. The results showed that concrete activated with powdered sodium silicate and lime had minimal slump loss over 2 hours and achieved similar 1-day compressive strengths as portland cement concrete when cured at normal temperatures. However, it exhibited higher drying shrinkage. Overall, alkali-activated slag concrete shows potential as a viable alternative to portland cement concrete.
Early age strength and workability of slag pastes activated by sodium silicatesfrank collins
This document reports on an investigation into activating blast furnace slag with sodium silicates to achieve equivalent one-day strength to Portland cement at normal curing temperatures and reasonable workability. The effects of varying sodium silicate activator dosages on strength and workability are discussed. Tests on pastes, mortars and concretes showed that equivalent one-day strength to Portland cement is possible using sodium silicate activation at normal curing temperatures, with the strength decreasing as the silicate modulus increases. Workability was also found to decrease with increasing activator dosage.
Effect of activator dosage... (2014, SAICE, Shekhovtsova J)Maxim Kovtun
This document provides biographies of three researchers - Julia Shekhovtsova, Elsabe Kearsley, and Maxim Kovtun - from the University of Pretoria, South Africa. It discusses their educational backgrounds and fields of research, which include the use of fly ash in alkali-activated cement binders and building materials. The document also provides their contact details.
The Leading manufacturers, Suppliers, importers and exporters of a varied range of Carbon Products Calcined Petroleum Coke, Petroleum Coke, Cement & Cement Clinker, Petroleum ProductsPetroleum Products
This document summarizes a study on the strength and shrinkage properties of alkali-activated slag concrete (AASC) placed in a large concrete column. Key findings include:
1) The AASC had improved workability over time compared to ordinary portland cement concrete, with minimal slump loss over 2 hours.
2) The temperature development in the AASC column was similar to a blended cement column and slower than an ordinary portland cement column, with a smaller temperature difference between the interior and exterior.
3) The compressive strength of the AASC column was identical to ordinary portland cement concrete and stronger than blended cement concrete at 28 and 91 days.
4) Embedded strain gauges
Feasibility studies of geopolymer as a coating materialzerohead
The document discusses a study on the feasibility of using geopolymer as a coating material. The experimental program involved testing different raw materials and molar ratios to determine optimal properties. Results showed that a polysialate-siloxo type geopolymer with a Si/Al ratio of around 4.0, Na/Al ratio of 0.4-0.6, Si/Na ratio of 0.8-1.2, and H2O/Na ratio of 13-17 provided good workability, fast strength development, and potential as an environmentally friendly coating material. The conclusions determined composition ranges that achieved these qualities. Further studies could continue optimizing geopolymer for coating applications.
This document summarizes the development of geopolymer applications over 30 years by Prof. Joseph Davidovits and his research organizations. It describes early successes with fire-resistant wood panels in the 1970s, followed by applications of geopolymers in ceramics, bricks, and cement from the 1970s-1980s. A key innovation was developing a low-temperature process to transform kaolinite clay into a geopolymer binder. This led to liquid geopolymer binders in the 1980s and the invention of high-strength geopolymer cement in 1983 through a collaboration between Prof. Davidovits and Lone Star Industries.
Application of micromechanics on alkali activated materialsTran Nam
This document discusses applying micromechanical analysis to alkali-activated materials. It identifies the intrinsic Young's modulus of the N-A-S-H gel that forms in alkali-activated fly ash and metakaolin as approximately 18 GPa using nanoindentation testing. It then develops a two-scale homogenization model combined with percolation theory to upscale the intrinsic gel properties to the macroscale, reproducing experimental data. The model also demonstrates how the N-A-S-H gel stiffens with increased packing of solid gel particles during the alkali activation process.
Challenges for Concrete. Presenterat av professor Karen Scrivener, vinnare av Swedish Concrete Award 2015, på Träffpunkt Betong 15 den 7 oktober i Stockholm.
1) A trial was conducted injecting an enhanced calcium sorbent called Sorbacal® SPS at Great River Energy's Stanton Station to reduce SO2 emissions and meet regional haze compliance targets.
2) The trial successfully achieved over 85% SO2 removal and emission rates below 0.14 lb/MMBtu, meeting the target.
3) Monitoring of the electrostatic precipitator performance showed only minimal impacts from the sorbent injection, indicating good compatibility between the enhanced calcium sorbent and ESP operation.
The document discusses the constituents and applications of concrete. The key constituents of concrete are cement, water, sand, coarse aggregate, and chemical or mineral admixtures. Common cements used are OPC, PPC containing fly ash, and PSC containing slag. Blended cements like PPC and PSC provide benefits like improved workability and reduced heat development. The appropriate type of cement is chosen based on the application and exposure conditions of the concrete.
The document discusses geopolymer cement concretes as an alternative to traditional Portland cement concretes. Geopolymer cement concretes utilize industrial byproducts like fly ash and blast furnace slag instead of Portland cement, reducing CO2 emissions by around 80%. The cement industry contributes significantly to global CO2 emissions, so finding alternatives like geopolymer cement could help mitigate climate change issues. Geopolymer cement concretes form polymeric bonds between silica and alumina instead of calcium-silicate hydrates like Portland cement, but can achieve similar structural strength.
This document summarizes an experimental study on geopolymer concrete. Geopolymer concrete is an alternative to traditional Portland cement concrete that has lower environmental impact. It uses industrial byproducts like fly ash and blast furnace slag as its binding materials rather than Portland cement. The study explored how geopolymer concrete performs compared to ordinary concrete. It investigated the effects of different mixtures on the properties of geopolymer concrete, such as strength and durability. The results showed that geopolymer concrete has higher resistance to damage than standard concrete and allows waste materials like fly ash to be recycled instead of disposed in landfills.
Applications of geopolymer technology to waste stabilizationTran Nam
Douglas C. Comrie and colleagues conducted research on using geopolymers to stabilize hazardous wastes. Geopolymers are inorganic binders that solidify wastes into a hard material with high compressive strength. Testing showed geopolymers greatly reduced metal leaching from contaminated soils and wastes, meeting regulatory standards. The research demonstrates geopolymers are effective for both chemically stabilizing wastes and physically encapsulating wastes to isolate them from the environment.
Study the effect of addition of wast plastic on compressive and tensileIAEME Publication
This research studies the effect of adding waste plastic in three percentage 0.5% ،1%
And 1.5% by volume on plain structural lightweight concrete (SLWC) produced by using
crushed bricks as coarse lightweight aggregates (LWA) in a lightweight concrete mix
designed according to ACI committee 211-2-82 with mix proportion 1:1.5:3.5 by volume
.The w\c equal to 0.5 and cement content 425 kg\m3
. Different tests where performed for
fresh and hardened SLWC such, unit weight, compressive strength and two indirect tests of
tensile strength (splitting tensile and flexural strength).
The results demonstrated that the effect of addition of waste plastic was more
pronounced on the tensile strength of SLWC than the compressive strength.The maximum
increase of compressive, splitting tensile and flexural strengths at 28-days were 4.4; 29; 40.8
% in the SLWC containing 1% waste plastic.
“EXPERIMENTAL STUDY ON PARTIAL REPLACEMENT OF CEMENT BY SEWAGE SLUDGE ASH AND...IRJET Journal
This document presents an experimental study on the partial replacement of cement with sewage sludge ash (SSA) and ground granulated blast furnace slag (GGBS) in concrete. Concrete cubes, cylinders, and beams were cast with cement replaced by 7.5-15% SSA and 10-60% GGBS. The specimens were tested at 7 and 28 days to determine compressive strength, split tensile strength, and flexural strength. The results showed that concrete with 30% GGBS and 10.5% SSA replacement achieved the highest strengths, with compressive strengths increasing from 19.7-24.56 MPa at 7 days and 30.21-39.91 MPa at 28
Performance of overburden waste rocks as aggregate in concreteIRJET Journal
The document investigates using overburden waste rock from mining to partially replace coarse aggregate in concrete. 130 concrete specimens were prepared with 0-75% replacement and tested. Compressive strength decreased as replacement increased from 15-45% but remained useful up to 50% replacement. A statistical analysis found a correlation coefficient of 0.77, indicating consistency. Equations were developed to predict the strength decrease based on replacement percentage. The study concluded that overburden rock can replace up to 50% coarse aggregate while maintaining sufficient concrete strength for structural uses.
AN EXPERIMENTAL STUDY ON STRENGTH OF CONCRETE WITH PARTIAL REPLACEMENT OF CEM...IRJET Journal
This document summarizes an experimental study on the strength of concrete with partial replacement of cement by Alccofine and fine aggregate by copper slag. Cubes and cylinders of M50 grade concrete were cast with 0-18% cement replacement by Alccofine and 0-66% fine aggregate replacement by copper slag. Testing included slump, compressive strength, split tensile strength, and flexural strength at 7 and 28 days. Results showed workability decreases with higher replacement levels due to increased water demand. Compressive strength increased up to 12% cement replacement by Alccofine and 44% fine aggregate replacement by copper slag but then decreased at higher replacement levels. The optimum mix for strength and economy was found to
This study investigated the mechanical and durability properties of high strength concrete (HPC) using silica fume and steel fiber additions. The concrete mixtures contained 10% silica fume replacement of cement by weight, and steel fiber contents of 1%, 1.5%, and 2% by volume. Testing showed that HPC with 2% steel fiber provided the highest compressive, split tensile, and flexural strengths. Impact resistance and modulus of elasticity also increased with higher steel fiber content. Addition of silica fume and steel fiber improved the bond strength and reduced chloride permeability compared to normal concrete. This experimental investigation demonstrated that using silica fume and steel fiber can enhance the mechanical and durability characteristics of high strength
International Journal of Computational Engineering Research (IJCER) is dedicated to protecting personal information and will make every reasonable effort to handle collected information appropriately. All information collected, as well as related requests, will be handled as carefully and efficiently as possible in accordance with IJCER standards for integrity and objectivity
Experimental Study on Concrete with Partial Replacement of Cement with GGBS a...IRJET Journal
This study experimentally investigated the effect of partially replacing cement with ground granulated blast furnace slag (GGBS) and river sand with steel slag on the compressive strength of concrete. Concrete cubes of M20 grade were cast by replacing cement with 0%, 5%, 10%, 15%, 20%, and 25% GGBS and river sand with 0%, 10%, 20%, 30%, and 40% steel slag. Compressive strength tests at 7 and 28 days showed that concrete with 15% GGBS replacement of cement and 30% steel slag replacement of river sand achieved the highest compressive strength compared to other mixes and the control concrete. Therefore, the optimal mix was determined to be 15% GGBS and 30% steel
Experimental Investigation of Granulated Blast Furnace Slag as Fine Aggregate...IRJET Journal
This document presents an experimental investigation on the use of granulated blast furnace slag (GBFS) as a replacement for natural river sand in concrete. The objectives are to determine the optimum GBFS content, and to study the effect on concrete's compression, tension, and flexural strengths. Concrete cubes, cylinders, and beams were cast with GBFS replacements of 25-50%. Testing showed maximum compression and tension strengths at 30% replacement. The optimum GBFS content was determined to be 30%, providing an increase of up to 22.6% in strength over conventional concrete.
This document presents research on the compressive strength of bamboo leaf ash (BLA) blended cement concrete cured in different sulphate environments. Concrete cubes with 0%, 5%, 10%, and 15% replacement of cement with BLA were cured in water and sulphate solutions of varying concentrations for 21 and 28 days. Testing found that BLA concrete strengths generally increased with higher sulphate concentrations and longer curing times compared to plain cement concrete. Replacement of 10% cement with BLA produced the highest strengths. The results indicate BLA concrete has improved sulphate resistance and could be suitable for use in sulphate environments where early strength is not critical.
IRJET-Study on the Mechanical Properties of Concrete by Replacement of Coal B...IRJET Journal
This study investigated the mechanical properties of concrete with coal bottom ash used as a partial replacement for fine aggregate at percentages ranging from 0% to 100%. Thirty concrete cubes, fifteen cylinders, and fifteen beams were cast using an M-40 grade concrete mix with a water-to-cement ratio of 0.40. Tests were performed to determine the compressive strength, split tensile strength, and flexural strength of the samples at 7 and 28 days. The results showed that as the percentage of bottom ash replacement increased, the measured strengths generally decreased, with strengths reducing most significantly above 50% replacement. Up to 30% replacement, the strength properties were approximately equivalent to the controlled concrete mix without bottom ash.
use of blast furnace slag in road construction. reportNagarjunJH
This document summarizes research on using blast furnace slag in road construction. It discusses the strength development of concretes with slag additions and how curing temperature affects strength. It also examines developing engineered cementitious composites with slag and stabilizing expansive clay soils using slag. The research found that slag concretes gain strength more slowly initially but can achieve equivalent strengths of ordinary Portland cement concretes at later ages. It also determined that curing temperature significantly impacts strength development. The document concludes that slag may be recommended as a hydraulic binder for road materials when used with activators like lime.
This document summarizes the results of a study on the strength and durability characteristics of ternary concrete made with cement, fly ash, and silica fume. Cubes, cylinders, and beams were cast with M25 grade concrete containing 5%, 7.5%, 10%, or 12.5% replacements of cement. Testing found that compressive, tensile, and flexural strengths at 7, 28, and 56 days were highest with 10% replacement, reaching maximum increases of 132% in compressive strength compared to conventional concrete. Durability was also assessed through weight loss and compressive strength testing of cubes exposed to acids and seawater. The study provides data on using supplementary cementitious materials to improve concrete properties
Experimental Studies on Concrete for the Partial Replacement of Cement by Egg...IRJET Journal
This document presents the results of an experimental study on concrete with partial replacement of cement by egg shell powder and ground granulated blast furnace slag (GGBS). Egg shell powder was varied up to 12.5% and GGBS was added from 20% to 35% as a partial replacement for cement. The properties tested included workability, compressive strength, split tensile strength, and shear strength. The results showed that concrete with 10% egg shell powder and 25% GGBS achieved the highest compressive strength of 25.47 MPa at 7 days and 40.15 MPa at 28 days, indicating that these waste materials can improve concrete strength when used as partial cement replacements.
EXPERIMENTAL STUDY OF EFFECTS OF POTASSIUM CARBONATE ON STRENGTH PARAMETERS O...IAEME Publication
This study presents the effects of Potassium Carbonate (K2CO3) on plain concrete. Potassium carbonate as depressant admixture was added in different percentages by weight of cement. The concrete specimens were tested for compressive, flexural and split tensile strengths and the results
obtained were compared with those of normal concrete. The optimum percentage of admixture that could be used without harming the properties of concrete was also assessed. The results concluded permissibility of using admixture (K2CO3) up to 2.6% by weight of cement.
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.
Influence of waste glass powder, ggbs, fly ash on the properties of concretebhimaji40
The document discusses the use of waste glass powder, fly ash, and GGBS as partial replacements for cement in concrete. The objectives are to determine the optimal percentage replacements and their effects on the mechanical properties and durability of concrete. The methodology describes tests conducted to evaluate the workability, compressive strength, split tensile strength, flexural strength, pullout strength, water absorption, rebound hammer test, and chloride permeability of concrete mixtures with varying replacement levels of cement. The results show improvements in strength and durability up to 15% replacement, with workability decreasing as the percentage of replacements increases.
1) The document investigates the compressive strength and carbonation of pre-cast concrete containing fly ash and silpozz cured in sea water over different time periods.
2) Ten concrete mixtures were designed to study the effects of curing in normal water versus sea water on compressive strength over 7, 28, 90, 180, and 365 days. Carbonation depth was also measured for sea water cured samples.
3) Results found that blended cement concretes with higher fly ash content had higher carbonation. Compressive strength gain was better for normal water curing than sea water curing after 28 days.
COMPRESSIVE STRENGTH AND CARBONATION OF SEA WATER CURED BLENDED CONCRETE IAEME Publication
This paper investigates the influence of sea water on pre-cast concrete containing
industrial by-product materials such as fly ash (FA) and silpozz. The mix design is targeted for
M30 grade concrete. Ten concrete mixtures were designed to have the same degree of
workability with water to cementitious material ratio of 0.43. The studied parameters include
the compressive strength of normal water curing (NWC) and sea water curing (SWC) samples
after 28 days of NWC for 7, 28, 90, 180 and 365 days curing period. The carbonation depth of
concrete samples for 28, 90, 180 and 365 days SWC after 28 days of NWC was measured. It
was found that the higher the FA content the higher is the carbonation process occurred. The
percentage increase in compressive strength for blended cement concrete in NWC is better
than the samples in SWC after 28 days of NWC
Strength Improvement of Mud Houses Through Stabilization of the Lateritic Mat...theijes
This paper reports an experimental investigation of the compressive strength of laterite stabilized with cement (CSL), lime (LSL) and rice straw (RSL) respectively. The laterites were collected from borrow pit used by locals in Bauchi, Nigeria to build mud houses. Unfortunately the mud houses experienced massive failures by through wall collapses over the years during the flooding cycles of the rainy seasons. An attempt is made to stabilize the lateritic soil materials used for the mud house walls in order to strengthen them against rains and flood erosions. Briefly discussed are factors that affect performance and strength, this include mix proportions, compaction, characteristics of the lateritic soil, mix procedure and curing. The results showed that the lateritic soils in the investigated area were relatively high on sand and lower on clay thereby promoting cement as the best stabilizer for strength. It increased the compressive strength by 661% from 0.61 N/mm2 at zero stabilization (ZSL) to 4.64 N/mm2 at 8% cement content after 28 days of curing. LSL and RSL at the same contents had strengths of 1.21 N/mm2 (98.4% increase) and 0.71 N/mm2 (16.4% increase) respectively. At 6% contents strength values were 4.33 N/mm2 , 1.16 N/mm2 and 0.66 N/mm2 respectively. The values reduced at 4% contents reporting 3.14N/mm2 , 0.82N/mm2 and 0.44N/mm2 respectively. While CSL increased non-linearly in density with increase in cement content, LSL and RSL decreased with increase of the respective contents. The results show that with cement as the stabilizer, mud house walls constructed with CSL bricks will resist collapse failures due to the perennial flooding in the area. Moreover by their relatively high compressive strengths they can be used for load bearing walls as much as sandcrete blocks
Flexural behaviour of reinforced concrete slabs using steel slag as coarse ag...eSAT Publishing House
This document summarizes an experimental investigation on the flexural behavior of reinforced concrete slabs using steel slag as a partial replacement for coarse aggregate. Concrete mixes of M30 and M40 grade were prepared with 0%, 30%, 60%, and 100% replacement of 20mm coarse aggregate with steel slag. Slabs of size 1400x1200x100mm were cast for each mix. Tests conducted included slump, rebound hammer, ultrasonic pulse velocity, compression testing of cubes, and flexural testing of slabs. Results showed that 60% steel slag replacement attained the maximum strength for both grades. Complete replacement of coarse aggregate with steel slag reduced surface hardness but provided adequate workability at 50% fine aggregate content.
2. 460 F. Collins, J.G. Sanjayan/Cement and Concrete Research 29 (1999) 459–462
The term water/binder (w/b) ratio is used instead of the
conventional water/cement ratio to include all the binder
types mentioned above. The slag is supplied with gypsum
(2% SO3 by mass of slag) that is blended with the slag. The
activators and adjuncts utilised were powdered sodium
metasilicate and hydrated lime. The powdered silicate acti-
vator was preblended with the slag in the dry form prior to
use for concrete manufacture. The hydrated lime was added
to the mix in the form of slurry. Adjustments were made to
the water added to the mixes to account for the free water
contained in the slurry, sodium metasilicate, and aggregates.
The coarse aggregate consisted of 14-mm maximum size
basalt which has a specific gravity of 2.95 and 24-h water
absorption of 1.2%. The fine aggregate consisted of river
sand which has a specific gravity of 2.65 and 24-h water ab-
sorption of 0.5%. Proportioning of the concrete mixes was
based on saturated and surface dry aggregate condition. The
concrete mixture proportions are summarised in Table 2.
The concrete mixing and testing was conducted in accor-
dance with the Australian Standard AS1012 Methods of
Testing Concrete. Testing for the properties of fresh and
hardened concretes (unless otherwise noted) included:
slump at time of mixing and at 30, 60, 90, and 120 min after
mixing; air content; and compressive strength. Compressive
strengths were measured using standard 100-mm diameter ϫ
200-mm long cylinders.
2. Fresh concrete properties
Slump loss versus time for each of the concrete types is
summarised in Fig. 1. AAS concrete demonstrates consider-
ably better workability than OPC concrete (115-mm initial
slump compared with 75-mm initial slump for OPC con-
crete). At 30 min, AAS concrete demonstrates better slump
than the initial value and at 120 min the slump loss of AAS
concrete is minimal compared with OPC concrete, which
loses 73% of the original slump.
AAS/CSF concrete has significantly less workability
than AAS concrete, with a reduction in initial slump from
115 to 37 mm. This type of concrete requires use of a super-
plasticiser to overcome low workability. There was a minor
improvement in slump at 30 min; however, considerable
Table 1
Properties of cementitious materials
Oxide composition/property Slag OPC UFS UFA CSF
SiO2 (%) 35.04 19.9 33.2 67.6 93.5
TiO2 (%) 0.42 * * 0.86 *
Al2O3 (%) 13.91 4.62 14.6 23.4 0.06
Fe2O3 (%) 0.29 3.97 0.4 3.41 0.18
MnO (%) 0.43 * * * *
MgO (%) 6.13 1.73 5.5 0.6 0.09
CaO (%) 39.43 64.27 42.4 1.01 0.01
Na2O (%) 0.34 — 0.3 0.53 0.14
K2O (%) 0.39 0.57 0.44 1.49 0.05
P2O5 (%) Ͻ0.1 * * 0.12 0.03
Total sulphur as SO3 (%) 2.43 2.56 0.2 * 0.13
Sulphide sulphur as S2Ϫ
0.44 * * * *
Cl (p.p.m.) 80 * * * *
Fineness (m2
/kg) 460 342 1496 90% Ͻ 13.7 mm 18,300
Loss on ignition (%) 1.45 2.9 — 1.19 2.4
Time to initial set (hours) N/A 2.0 N/A N/A N/A
Strength of 75 ϫ 75 ϫ 75
mm mortar cubes (MPa)
3 Days N/A 32.7 N/A N/A N/A
7 Days N/A 42.0 N/A N/A N/A
28 Days N/A 54.1 N/A N/A N/A
* Not supplied.
Table 2
Summary of concrete mixture proportions (kg/m3)*
Concrete type
Binder OPC AAS AAS/CSF AAS/UFS AAS/UFA
OPC 364 — — — —
Slag†
— 347 313 314 308
CSF — — 34.8 — —
UFS — — — 35 —
UFA — — — — 34.3
Activator — 78.4 78.5 78.5 77.5
Free water 182 173.5 174 174.5 171.5
w/b 0.5 0.5 0.5 0.5 0.5
Fine aggregate 841 801 802 805 791
Coarse aggregate
14 mm
1145 1090 1091 1096
1077
Air content % 0.5 1.2 1.3 1.1 0.6
* All proportions adjusted for the yield volume.
†
Slag activated by addition of powdered sodium metasilicate and lime
slurry activator.
3. F. Collins, J.G. Sanjayan/Cement and Concrete Research 29 (1999) 459–462 461
slump loss was measured between 60 to 120 min. Neverthe-
less, the rate of slump loss was not as high during this pe-
riod as for the OPC concrete. AAS/UFS concrete was
slightly less workable than AAS (13% reduction in initial
slump), but better than OPC concrete and showed minimal
slump loss over 2 h. AAS/UFA concrete showed the best
workability, with 83% increase in the initial slump, fol-
lowed by 13% slump loss over 2 h. Following the elapse of
2 h the slump is superior to the initial slump of all of the
mixes.
3. Compressive strength
3.1. One-day strength
Compressive strength at one day is summarised for each
of the concrete types in Fig. 2. Each data set is the average
of three test results. AAS concrete shows almost identical
one-day strength as OPC concrete (15.1 and 14.9 MPa, re-
spectively). AAS/UFS, AAS/UFA, and AAS/CSF concretes
show improvement in one-day strength, with 28%, 24%,
and 10% increases, respectively. In the case of AAS/CSF,
use of a superplasticiser may have improved compressive
strength. However, the one-day strength may not reflect the
pattern of strength gain with age.
3.2. Strength development
Fig. 3 shows the strength development of the various
concrete mixes with time. Each data set for compressive
strength at 1, 3, 7, 28, 56, and 91 days is the average of three
test results. AAS concrete shows higher strength than OPC
concrete at all ages beyond one day. Between 56 and 91
days, the strength gain of the OPC control concrete levels
off, whereas AAS concrete continues to gain strength. AAS/
UFS shows marginally higher strength at all ages than both
OPC and AAS concretes. Although the strength improve-
ment of AAS/UFS concrete is significantly better than AAS
concrete between 7 and 56 days (10% higher than AAS con-
crete at 28 and 56 days), the improvement declines to 5% at
91 days. AAS/CSF concrete demonstrated the best strength
development at all ages beyond three days. The 91-day
strength of AAS/CSF concrete is 74.2 MPa, which is the
highest strength achieved on all the mixes and is 12%
higher than the corresponding strength of the AAS concrete.
Between 28 and 91 days, the slope of the strength-growth
curve for AAS/CSF concrete is almost identical to AAS
concrete, indicating the improvement in strength is mostly
due to the improved hydration of the binder.
Although one-day strength of AAS/UFA concrete is
higher than OPC and AAS concretes, the later age strengths
are not as high as those for AAS/CSF and AAS/UFS con-
cretes. At 56 days and beyond, the strength of the AAS/
UFA concrete was identical to OPC concrete. This may be
due to the lack of Ca(OH)2 in the binder to promote the poz-
zolanicity of the UFA.
4. Conclusions
The results of this investigation indicate:
1. AAS concrete demonstrates considerably better
workability than OPC at the time of mixing and
shows minimal slump loss over 2 h. Strength at ages
beyond one day is superior to OPC.
Fig. 1. Slump versus time.
Fig. 2. One-day compressive strength; w/b ϭ 0.5.
Fig. 3. Compressive strength with 10% replacement of slag with ultra-
fine materials; w/b ϭ 0.5.
4. 462 F. Collins, J.G. Sanjayan/Cement and Concrete Research 29 (1999) 459–462
2. AAS/UFA concrete shows significantly improved
slump compared to AAS concrete and 24% better
one-day strength; however, compressive strength of
concrete at ages beyond 28 days is less than AAS con-
crete and identical to OPC concrete.
3. AAS/CSF and AAS/UFS concretes show signifi-
cantly greater strength than AAS concrete at ages be-
yond one day. However, AAS/CSF concrete has sig-
nificant loss of workability whereas AAS/UFS has
minimal loss of workability compared with AAS con-
crete.
4. AAS/CSF concrete achieved the highest strength de-
velopment over the 91 days of curing and use of a su-
perplasticiser may overcome its lower workability
than AAS concrete.
Acknowledgments
The financial support for this project is jointly provided
by Independent Cement and Lime Pty Ltd, Blue Circle
Southern Cement Ltd, and Australian Steel Mill Services.
The authors thank the sponsors, especially Alan Dow, Tom
Wauer, Paul Ratcliff, Kathryn Turner, and Dr. Ihor Hinczak
for the guidance and support. The efforts and assistance
with the laboratory work provided by Eric Tan, Soon Keat
Lim, Jeff Doddrell, Roger Doulis, and Peter Dunbar are also
gratefully acknowledged.
References
[1] FIP State-of-the-Art Report—Condensed Silica Fume in Concrete,
Thomas Telford, London, 1988.
[2] ACI Committee 363 State-of-the-Art Report on High-Strength Con-
crete, ACI 4 (1984) 364.
[3] T. Tomisawa, M. Fuji, Proc. 5th Int. Conf. on Fly Ash, Slag, and Nat-
ural Pozzolans in Concrete, Milwaukee, ACI SP 153, 2 (1995) 951.
[4] Y. Ohama, J. Madej, K. Demura, Proc. 5th Int. Conf. on Fly Ash,
Slag, and Natural Pozzolans in Concrete, Milwaukee, ACI SP 153, 2
(1995) 1031.
[5] T. Tomisawa, T. Chikada, Y. Nagao, Proc. 4th Int. Conf. on Fly Ash,
Slag, and Natural Pozzolans in Concrete, Istanbul, Turkey, ACI SP
132 (1992) 1385.
[6] H.A.W. Cornelissen, R.E. Hellewaard, J.L.J. Vissers, Proc. 5th Int.
Conf. on Fly Ash, Slag, and Natural Pozzolans in Concrete, Milwau-
kee, ACI SP 153, 1 (1995) 67.
[7] W.B. Butler, Proc. Conf. Concrete 2000, R.K. Dhir, M.R. Jones
(Eds.), E and FN Spon, 1993, 1825.
[8] S. Wei, P. Ganghua, D. Dajun, Proc. 3d CANMET/ACI Conf. on
High Performance Concrete: Design and Materials and Recent Ad-
vances in Concrete Technology, ACI SP 172 (1997) 299.
[9] S.-D. Wang, K.L. Scrivener, P.L. Pratt, Cem Concr Res, 24 (1994)
1033.
[10] J. Bijen, H. Waltje, Proc. 3d Int. Conf. on Fly Ash, Slag, and Natural
Pozzolans in Concrete, Trondheim, Norway, ACI SP 114, 2 (1989) 1565.
[11] B. Talling, Proc. 3d Int. Conf. on Fly Ash, Slag, and Natural Poz-
zolans in Concrete, Trondheim, Norway, ACI SP 114, 2 (1989) 1485.
[12] B. Talling, J. Brandstetr, Proc. 3d Int. Conf. on Fly Ash, Slag, and
Natural Pozzolans in Concrete, Trondheim, Norway, ACI SP 114, 2
(1989) 1519.
[13] D.M. Roy, M.R. Silsbee, Mat Res Soc Symp Proc 245 (1992) 153.
[14] E. Douglas, J. Brandstetr, Cem Concr Res 20 (1990) 746.
[15] W.J. Clark, M. Helal, Mat Res Soc Symp Proc 179 (1989) 219.