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.
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
IRJET- Experimental Investigation on Glass Fibre Reinforced ConcreteIRJET Journal
This document summarizes an experimental investigation on the properties of glass fibre reinforced concrete (GFRC). Testing was conducted on conventional concrete (Mix 1) and GFRC (Mix 2) to determine workability, compressive strength, split tensile strength, and flexural strength at 7 and 28 days. The results showed that GFRC had higher strengths in all areas compared to conventional concrete, with compressive strength approximately 20-25% greater. Specifically, at 28 days Mix 2 achieved 41.1 MPa for compressive strength, 3.97 MPa for split tensile strength, and 4.92 MPa for flexural strength compared to Mix 1's results of 33.22 MPa, 3.17 MPa,
Study on Properties of Fresh and Hardened Self Compacting Concrete with Varie...IOSRJMCE
The objective of this paper is to study the properties of fresh and hardened self compacting concrete with varied percentages of metakaolin as mineral admixture (M40 grade). In this study cement is replaced by metakoalin with varied percentages, 20%, 22%, 24%, 26%, 28%, 30%, 32%, 34%, 36% & 38% with a constant packing factor of 1.14. In the present study, B233 GLENIUM super plasticizer is used. As per the European guidelines for Self-compacting concrete, the workability tests such as slump flow test, V-funnel test and L- box, U-box test were carried out in laboratory. The concrete specimens were cured in the tank for 7 and 28 days and tested for determining the compressive strength and split tensile strength and flexural strength respectively. From the study it is observed that workability and mechanical properties such as Compressive strength, Split tensile strength and Flexural strength test increased with increase in metakoalin up to 30% and decreased from 32% to 38%. Non Destructive Test is also performed to assess the quality of concrete in the hardened state.
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.
Mix design and mechanical properties of self compacting light weight concreteYahaya Hassan Labaran
A presentation based on a research paper review assignment
A.A. Maghsoudi1, Sh. Mohamadpour2, M. Maghsoudi, Mix design and mechanical properties of self compacting light
weight concrete:International Journal of civil Engineering, Vol 9, No 3. september 2011
This document presents a study on predicting the compression strength of normal and lightweight aggregate concrete through non-destructive testing methods. Five concrete mixes with varying proportions of normal and lightweight aggregate were tested. Ultrasonic pulse velocity testing was used to measure the transit time of ultrasonic pulses through the concrete. A regression analysis found a power function relationship between compressive strength and pulse velocity with R^2 of 1.0. A similar relationship was found between modulus of elasticity and pulse velocity. The study aims to apply non-destructive testing methods such as ultrasonic pulse velocity to evaluate properties of normal and lightweight aggregate concrete.
Recreated Masonry Sub Assemblages for Characterization of the Existing MasonryAlokSinghTomar
This document summarizes research on evaluating the mechanical properties of existing masonry structures without damaging them. The researchers created reassembled masonry specimens using bricks and mortar sourced from the existing structure. Chemical tests determined the composition of the original mortar. Compression and shear tests on the reassembled specimens showed similar behavior to tests on samples removed from the structure. Finite element modeling validated using the reassembled specimens to estimate properties like compressive strength and shear strength without harming the historic structure. The reassembled specimens provided reliable data for assessing and retrofitting the existing masonry building.
Non Destructive Testing of Concrete CubesAvishek Ghosh
This document summarizes a presentation on non-destructive testing of concrete cubes under varied curing conditions. The presentation discusses rebound hammer testing and ultrasonic pulse velocity testing conducted on concrete cubes cured under four different curing regimes to determine compressive strength and detect voids. Key findings include the 14 days curing regime achieved the target compressive strength, placement of transducers impacts void detection by ultrasonic pulse velocity, and rebound hammer strengths were slightly lower than compressive strengths. The presentation concludes with references for further information.
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
IRJET- Experimental Investigation on Glass Fibre Reinforced ConcreteIRJET Journal
This document summarizes an experimental investigation on the properties of glass fibre reinforced concrete (GFRC). Testing was conducted on conventional concrete (Mix 1) and GFRC (Mix 2) to determine workability, compressive strength, split tensile strength, and flexural strength at 7 and 28 days. The results showed that GFRC had higher strengths in all areas compared to conventional concrete, with compressive strength approximately 20-25% greater. Specifically, at 28 days Mix 2 achieved 41.1 MPa for compressive strength, 3.97 MPa for split tensile strength, and 4.92 MPa for flexural strength compared to Mix 1's results of 33.22 MPa, 3.17 MPa,
Study on Properties of Fresh and Hardened Self Compacting Concrete with Varie...IOSRJMCE
The objective of this paper is to study the properties of fresh and hardened self compacting concrete with varied percentages of metakaolin as mineral admixture (M40 grade). In this study cement is replaced by metakoalin with varied percentages, 20%, 22%, 24%, 26%, 28%, 30%, 32%, 34%, 36% & 38% with a constant packing factor of 1.14. In the present study, B233 GLENIUM super plasticizer is used. As per the European guidelines for Self-compacting concrete, the workability tests such as slump flow test, V-funnel test and L- box, U-box test were carried out in laboratory. The concrete specimens were cured in the tank for 7 and 28 days and tested for determining the compressive strength and split tensile strength and flexural strength respectively. From the study it is observed that workability and mechanical properties such as Compressive strength, Split tensile strength and Flexural strength test increased with increase in metakoalin up to 30% and decreased from 32% to 38%. Non Destructive Test is also performed to assess the quality of concrete in the hardened state.
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.
Mix design and mechanical properties of self compacting light weight concreteYahaya Hassan Labaran
A presentation based on a research paper review assignment
A.A. Maghsoudi1, Sh. Mohamadpour2, M. Maghsoudi, Mix design and mechanical properties of self compacting light
weight concrete:International Journal of civil Engineering, Vol 9, No 3. september 2011
This document presents a study on predicting the compression strength of normal and lightweight aggregate concrete through non-destructive testing methods. Five concrete mixes with varying proportions of normal and lightweight aggregate were tested. Ultrasonic pulse velocity testing was used to measure the transit time of ultrasonic pulses through the concrete. A regression analysis found a power function relationship between compressive strength and pulse velocity with R^2 of 1.0. A similar relationship was found between modulus of elasticity and pulse velocity. The study aims to apply non-destructive testing methods such as ultrasonic pulse velocity to evaluate properties of normal and lightweight aggregate concrete.
Recreated Masonry Sub Assemblages for Characterization of the Existing MasonryAlokSinghTomar
This document summarizes research on evaluating the mechanical properties of existing masonry structures without damaging them. The researchers created reassembled masonry specimens using bricks and mortar sourced from the existing structure. Chemical tests determined the composition of the original mortar. Compression and shear tests on the reassembled specimens showed similar behavior to tests on samples removed from the structure. Finite element modeling validated using the reassembled specimens to estimate properties like compressive strength and shear strength without harming the historic structure. The reassembled specimens provided reliable data for assessing and retrofitting the existing masonry building.
Non Destructive Testing of Concrete CubesAvishek Ghosh
This document summarizes a presentation on non-destructive testing of concrete cubes under varied curing conditions. The presentation discusses rebound hammer testing and ultrasonic pulse velocity testing conducted on concrete cubes cured under four different curing regimes to determine compressive strength and detect voids. Key findings include the 14 days curing regime achieved the target compressive strength, placement of transducers impacts void detection by ultrasonic pulse velocity, and rebound hammer strengths were slightly lower than compressive strengths. The presentation concludes with references for further information.
Design of High Compressive Strength Concrete Mix without AdditivesIJERA Editor
In this paper, the crashed Basalt and uncrushed granite is used in concrete mixes as coarse aggregate. The selected materials, with high specification using special production techniques, the properties ,the mix design procedure and mix proportion of the high strength concrete (HSC) were discussed. Different proportions of Ordinary Portland cement (410,430 and 450) kg/m3 with different crashed Basalt and uncrushed Granite coarse aggregate amount (1120 and 1050) kg/m3 and fine aggregate with fine modulus of 3.65 were used. Eight concrete mixes were prepared: two as control mix for crashed Basalt and uncrushed Granite, three with crashed Basalt and three with uncrushed Granite coarse aggregate with mix amount(410:680:1120,430:610:1050 and 450:550:1050) kg/m3,(cement: fine aggregate: coarse aggregate)respectively. The study showed that the use of granite coarse aggregate in concrete mixes has a clear effect in mix proportion. The compressive strength of concrete was measured at ages of 7, 28 and 56 days and it was found that the granite (Mix3) of (450:550:1050) kg/m3 with w/c of 0.46 give the highest of strength in 28 and 56 days among the abovementioned mixes its 56 and 64 N/mm2 respectively. The paper shows that good results of compressive strength and workability of concrete were obtained when using granite coarse aggregate.
This study establishes correlations between destructive and non-destructive testing of concrete compressive strength. Concrete cubes were cured for 7, 14, and 28 days and tested destructively via compression and non-destructively using a rebound hammer. Regression analysis found strong linear correlations (R2 91.6-97.9%) between rebound number and compressive strength. Models were able to predict compressive strength to within 1.3-1.8% of actual values on average, indicating rebound hammer can be used to accurately estimate compressive strength non-destructively.
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.
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
An Experimental Investigation on Steel Fiber Reinforced Concrete with Partial...IRJET Journal
This document summarizes an experimental investigation on steel fiber reinforced concrete with partial replacement of natural sand by manufactured sand. Cubes, cylinders, prisms, and L-shaped specimens of M30 grade concrete with 50% replacement of natural sand by manufactured sand and 1% steel fibers were cast and tested at 7, 14, and 28 days to evaluate mechanical properties. The tests included compressive strength, split tensile strength, flexural strength, shear strength, and the effect of high temperatures. The study aims to compare the mechanical performance of steel fiber reinforced concrete with manufactured sand to normal concrete.
The Journal of MC Square Scientific Research is published by MC Square Publication on the monthly basis. It aims to publish original research papers devoted to wide areas in various disciplines of science and engineering and their applications in industry. This journal is basically devoted to interdisciplinary research in Science, Engineering and Technology, which can improve the technology being used in industry. The real-life problems involve multi-disciplinary knowledge, and thus strong inter-disciplinary approach is the need of the research.
Destructive and Non- Destructive Testing for Concrete in Sudan - A Comparativ...iosrjce
IOSR Journal of Mechanical and Civil Engineering (IOSR-JMCE) is a double blind peer reviewed International Journal that provides rapid publication (within a month) of articles in all areas of mechanical and civil engineering and its applications. The journal welcomes publications of high quality papers on theoretical developments and practical applications in mechanical and civil engineering. Original research papers, state-of-the-art reviews, and high quality technical notes are invited for publications.
A Study on Behavior of Reinforcement Concrete Beam using the Recycled ConcreteĐức Vũ
1) The study investigates the flexural behavior and performance of reinforced concrete beams containing 20% recycled concrete aggregate (RCA) as a partial replacement for natural aggregates.
2) Testing of concrete mixtures found a 1.7% reduction in compressive strength and 6% reduction in tensile strength for mixtures containing 20% RCA compared to normal concrete.
3) Beam testing showed ultimate loads reduced by up to 6.27% for beams with 20% RCA, with increased deflections and crack widths compared to a reference beam without RCA.
Study Of Characteristics Strength of Concrete with Admixtures by Flexural and...IJERA Editor
Concrete is widely used in structural engineering with its high compressive strength, low cost and abandoned raw material, but common concrete has some deficiency, such as shrinkage and cracking, low tensile strength and flexural strength, high brittleness, that restrict its applications. To overcome these deficiencies’ additional materials are added to improve the performance of the concrete. Super plasticizer is a chemical added to conventional concrete mix that makes the concrete more workable and it can be placed easily. The aim of this project work to study the characteristics strengths of concrete such as compressive strength, flexural strength, split tensile strength, diametric strength and tensile strength by disc bending test. For the experimental work normal concrete M 40 has to be prepared and characteristics strength such as compressive strength, tensile strength, and flexural strength have to be achieved. This strength has to be performed after 7 days and 28 days curing. After that in addition of super plasticizer the study of the strength have to be performed with various % of plasticizer such as 0.60% to 1.2 % by the weight of cement and study of strength of concrete have to be performed at 7 days and 28 days. A relative comparison of the strength of the concrete with addition of admixtures with normal concrete can be study.
This document summarizes a study on using recycled concrete aggregate in concrete. It discusses that recycled aggregate can reduce environmental impacts from construction waste and lower costs. The study tested the compressive strength, split tensile strength, and flexural strength of concrete with 20%, 40%, and 60% replacement of natural coarse aggregate with recycled aggregate. The 40% replacement mix achieved the highest strengths. The study concluded that recycled aggregate concrete can meet design requirements and is a sustainable construction material option.
Construction Materials Engineering and Testingmecocca5
This document provides an overview of materials testing services for soil, aggregate, concrete, and masonry. It describes common laboratory and field tests for evaluating the properties and quality of construction materials, including tests for soil particle size and compaction, concrete slump and strength, and masonry compressive strength. The document emphasizes that materials testing should be performed by properly trained personnel according to standardized test methods and that test results should be reported in a timely manner.
International Journal of Engineering Research and Development is an international premier peer reviewed open access engineering and technology journal promoting the discovery, innovation, advancement and dissemination of basic and transitional knowledge in engineering, technology and related disciplines.
We follow "Rigorous Publication" model - means that all articles appear on IJERD after full appraisal, effectiveness, legitimacy and reliability of research content. International Journal of Engineering Research and Development publishes papers online as well as provide hard copy of Journal to authors after publication of paper. It is intended to serve as a forum for researchers, practitioners and developers to exchange ideas and results for the advancement of Engineering & Technology.
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
The document discusses the effects of micro silica particle size and dosage on the compressive strength of concrete. 240 concrete cube specimens were made with micro silica particle sizes of 20, 45, 90, 125, and 250 microns and replacement levels of cement of 10%, 20%, 30%, and 40%. Testing found that compressive strength increased as particle size decreased and was highest for 20 micron particle size and 20% cement replacement. The optimum strength was 42% higher than the control mix at 28 days. Smaller particle size provides a greater surface area and allows better accommodation in the cement porous structure.
Recycling Dumped Concrete for Making Concrete Paving Blocksdrboon
This study applies recycled concrete as a replacement of coarse aggregate to produce concrete paving blocks. The experiment is conducted to observe concrete strength of the specimen samples. The Thai Industrial Standard for concrete paving blocks (TIS 827-2531) has specified concrete samples at 28 days to have compressive strength surplus 350ksc. This study, recycled concrete has been used at various proportions, 50%, 70%, and 100% replacement of coarse aggregate. The mix concrete uses water-cement ratio 0.47 with design slump 10±2.5cm. Average concrete strengths at 28days are 665 ksc, 456 ksc and 350 ksc. Thus, this work shows possibility that dumped concrete can be recycled with full 100% replacement of coarse aggregate in making concrete paving blocks.
The document discusses experimental investigations into the material properties and compressive/shear behavior of brick masonry with different mortar ratios. Tests were conducted on brick units, mortar cubes/cylinders, and brick prism triplets with varying mortar ratios to evaluate properties like compressive strength, bond strength, and interface behavior. The results were then evaluated and compared to better understand the behavior of unreinforced brick masonry under shear and compression loading for use in numerical simulations.
Abstract
The paper presents the studies on properties of blended concretes containing various mineral admixtuers like fly ash, silica fume, ground granulated blast furnace slag and metakaolin as partial replacement to cement. By addition of these admixtures reduces the cement content so that it can minimize the enivornment impact from the producion of cement.Various properties of blended concretes are reviewed from different research articles.
Keywords- Blended Concrete, Binary Blended, Triple Blended, Quaternary Blended Concretes, Strength Properties, Durability Properties
This study investigated the effects of adding nano silica to fly ash concrete. Fly ash was partially replaced with cement at various percentages from 0-80%. Nano silica was then added at 2.5% of the cement weight. Corrosion resistance and flexural strength were evaluated. Test results showed that nano silica fly ash concrete had lower mass loss, smaller cracks, and higher strength compared to plain fly ash concrete. This indicates nano silica improves corrosion resistance and strength even when fly ash replaces cement. The optimal fly ash replacement was found to be 30-40% to maintain strength while nano silica helped compensate for strength loss from fly ash addition.
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
Conventional Concrete by using Basalt FiberIRJET Journal
This document investigates the effect of adding basalt fiber on the mechanical properties of concrete. Basalt fiber is added in volumes ranging from 0.1% to 0.5% of the total concrete volume. Experimental results show that:
1) The addition of basalt fiber up to 0.3% volume fraction improves the compressive and flexural strength of concrete compared to conventional concrete without fiber. The highest strengths were observed at 0.3% fiber content.
2) There is a negligible influence of basalt fiber addition on the splitting tensile strength of concrete.
3) Concrete with 0.3% basalt fiber content showed the best performance with a 12.34% and 12.94
Design of High Compressive Strength Concrete Mix without AdditivesIJERA Editor
In this paper, the crashed Basalt and uncrushed granite is used in concrete mixes as coarse aggregate. The selected materials, with high specification using special production techniques, the properties ,the mix design procedure and mix proportion of the high strength concrete (HSC) were discussed. Different proportions of Ordinary Portland cement (410,430 and 450) kg/m3 with different crashed Basalt and uncrushed Granite coarse aggregate amount (1120 and 1050) kg/m3 and fine aggregate with fine modulus of 3.65 were used. Eight concrete mixes were prepared: two as control mix for crashed Basalt and uncrushed Granite, three with crashed Basalt and three with uncrushed Granite coarse aggregate with mix amount(410:680:1120,430:610:1050 and 450:550:1050) kg/m3,(cement: fine aggregate: coarse aggregate)respectively. The study showed that the use of granite coarse aggregate in concrete mixes has a clear effect in mix proportion. The compressive strength of concrete was measured at ages of 7, 28 and 56 days and it was found that the granite (Mix3) of (450:550:1050) kg/m3 with w/c of 0.46 give the highest of strength in 28 and 56 days among the abovementioned mixes its 56 and 64 N/mm2 respectively. The paper shows that good results of compressive strength and workability of concrete were obtained when using granite coarse aggregate.
This study establishes correlations between destructive and non-destructive testing of concrete compressive strength. Concrete cubes were cured for 7, 14, and 28 days and tested destructively via compression and non-destructively using a rebound hammer. Regression analysis found strong linear correlations (R2 91.6-97.9%) between rebound number and compressive strength. Models were able to predict compressive strength to within 1.3-1.8% of actual values on average, indicating rebound hammer can be used to accurately estimate compressive strength non-destructively.
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.
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
An Experimental Investigation on Steel Fiber Reinforced Concrete with Partial...IRJET Journal
This document summarizes an experimental investigation on steel fiber reinforced concrete with partial replacement of natural sand by manufactured sand. Cubes, cylinders, prisms, and L-shaped specimens of M30 grade concrete with 50% replacement of natural sand by manufactured sand and 1% steel fibers were cast and tested at 7, 14, and 28 days to evaluate mechanical properties. The tests included compressive strength, split tensile strength, flexural strength, shear strength, and the effect of high temperatures. The study aims to compare the mechanical performance of steel fiber reinforced concrete with manufactured sand to normal concrete.
The Journal of MC Square Scientific Research is published by MC Square Publication on the monthly basis. It aims to publish original research papers devoted to wide areas in various disciplines of science and engineering and their applications in industry. This journal is basically devoted to interdisciplinary research in Science, Engineering and Technology, which can improve the technology being used in industry. The real-life problems involve multi-disciplinary knowledge, and thus strong inter-disciplinary approach is the need of the research.
Destructive and Non- Destructive Testing for Concrete in Sudan - A Comparativ...iosrjce
IOSR Journal of Mechanical and Civil Engineering (IOSR-JMCE) is a double blind peer reviewed International Journal that provides rapid publication (within a month) of articles in all areas of mechanical and civil engineering and its applications. The journal welcomes publications of high quality papers on theoretical developments and practical applications in mechanical and civil engineering. Original research papers, state-of-the-art reviews, and high quality technical notes are invited for publications.
A Study on Behavior of Reinforcement Concrete Beam using the Recycled ConcreteĐức Vũ
1) The study investigates the flexural behavior and performance of reinforced concrete beams containing 20% recycled concrete aggregate (RCA) as a partial replacement for natural aggregates.
2) Testing of concrete mixtures found a 1.7% reduction in compressive strength and 6% reduction in tensile strength for mixtures containing 20% RCA compared to normal concrete.
3) Beam testing showed ultimate loads reduced by up to 6.27% for beams with 20% RCA, with increased deflections and crack widths compared to a reference beam without RCA.
Study Of Characteristics Strength of Concrete with Admixtures by Flexural and...IJERA Editor
Concrete is widely used in structural engineering with its high compressive strength, low cost and abandoned raw material, but common concrete has some deficiency, such as shrinkage and cracking, low tensile strength and flexural strength, high brittleness, that restrict its applications. To overcome these deficiencies’ additional materials are added to improve the performance of the concrete. Super plasticizer is a chemical added to conventional concrete mix that makes the concrete more workable and it can be placed easily. The aim of this project work to study the characteristics strengths of concrete such as compressive strength, flexural strength, split tensile strength, diametric strength and tensile strength by disc bending test. For the experimental work normal concrete M 40 has to be prepared and characteristics strength such as compressive strength, tensile strength, and flexural strength have to be achieved. This strength has to be performed after 7 days and 28 days curing. After that in addition of super plasticizer the study of the strength have to be performed with various % of plasticizer such as 0.60% to 1.2 % by the weight of cement and study of strength of concrete have to be performed at 7 days and 28 days. A relative comparison of the strength of the concrete with addition of admixtures with normal concrete can be study.
This document summarizes a study on using recycled concrete aggregate in concrete. It discusses that recycled aggregate can reduce environmental impacts from construction waste and lower costs. The study tested the compressive strength, split tensile strength, and flexural strength of concrete with 20%, 40%, and 60% replacement of natural coarse aggregate with recycled aggregate. The 40% replacement mix achieved the highest strengths. The study concluded that recycled aggregate concrete can meet design requirements and is a sustainable construction material option.
Construction Materials Engineering and Testingmecocca5
This document provides an overview of materials testing services for soil, aggregate, concrete, and masonry. It describes common laboratory and field tests for evaluating the properties and quality of construction materials, including tests for soil particle size and compaction, concrete slump and strength, and masonry compressive strength. The document emphasizes that materials testing should be performed by properly trained personnel according to standardized test methods and that test results should be reported in a timely manner.
International Journal of Engineering Research and Development is an international premier peer reviewed open access engineering and technology journal promoting the discovery, innovation, advancement and dissemination of basic and transitional knowledge in engineering, technology and related disciplines.
We follow "Rigorous Publication" model - means that all articles appear on IJERD after full appraisal, effectiveness, legitimacy and reliability of research content. International Journal of Engineering Research and Development publishes papers online as well as provide hard copy of Journal to authors after publication of paper. It is intended to serve as a forum for researchers, practitioners and developers to exchange ideas and results for the advancement of Engineering & Technology.
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
The document discusses the effects of micro silica particle size and dosage on the compressive strength of concrete. 240 concrete cube specimens were made with micro silica particle sizes of 20, 45, 90, 125, and 250 microns and replacement levels of cement of 10%, 20%, 30%, and 40%. Testing found that compressive strength increased as particle size decreased and was highest for 20 micron particle size and 20% cement replacement. The optimum strength was 42% higher than the control mix at 28 days. Smaller particle size provides a greater surface area and allows better accommodation in the cement porous structure.
Recycling Dumped Concrete for Making Concrete Paving Blocksdrboon
This study applies recycled concrete as a replacement of coarse aggregate to produce concrete paving blocks. The experiment is conducted to observe concrete strength of the specimen samples. The Thai Industrial Standard for concrete paving blocks (TIS 827-2531) has specified concrete samples at 28 days to have compressive strength surplus 350ksc. This study, recycled concrete has been used at various proportions, 50%, 70%, and 100% replacement of coarse aggregate. The mix concrete uses water-cement ratio 0.47 with design slump 10±2.5cm. Average concrete strengths at 28days are 665 ksc, 456 ksc and 350 ksc. Thus, this work shows possibility that dumped concrete can be recycled with full 100% replacement of coarse aggregate in making concrete paving blocks.
The document discusses experimental investigations into the material properties and compressive/shear behavior of brick masonry with different mortar ratios. Tests were conducted on brick units, mortar cubes/cylinders, and brick prism triplets with varying mortar ratios to evaluate properties like compressive strength, bond strength, and interface behavior. The results were then evaluated and compared to better understand the behavior of unreinforced brick masonry under shear and compression loading for use in numerical simulations.
Abstract
The paper presents the studies on properties of blended concretes containing various mineral admixtuers like fly ash, silica fume, ground granulated blast furnace slag and metakaolin as partial replacement to cement. By addition of these admixtures reduces the cement content so that it can minimize the enivornment impact from the producion of cement.Various properties of blended concretes are reviewed from different research articles.
Keywords- Blended Concrete, Binary Blended, Triple Blended, Quaternary Blended Concretes, Strength Properties, Durability Properties
This study investigated the effects of adding nano silica to fly ash concrete. Fly ash was partially replaced with cement at various percentages from 0-80%. Nano silica was then added at 2.5% of the cement weight. Corrosion resistance and flexural strength were evaluated. Test results showed that nano silica fly ash concrete had lower mass loss, smaller cracks, and higher strength compared to plain fly ash concrete. This indicates nano silica improves corrosion resistance and strength even when fly ash replaces cement. The optimal fly ash replacement was found to be 30-40% to maintain strength while nano silica helped compensate for strength loss from fly ash addition.
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
Conventional Concrete by using Basalt FiberIRJET Journal
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4page summary
1. TENSILE CHARACTERISTICS OF NO
AGGREGATE CONCRETE
Abstract - This paper considers the tensile characteristics
of no aggregate concrete and its practical usability in
construction activities. In the present context most of the value
engineers look for modification in the conventional concrete to
enhance the performances and also to make construction
activities more feasible. Since this is a newly introduced
material it is essential to identify the major strength
characteristics of the material and the behavior in practical
situations. Therefore this paper has identified the basic
properties of the No Aggregate Concrete and the behavioral
patterns with various mixing proportions. At the same time it
has identified probable practical difficulties in real time
scenarios and suggestions to minimize those effects. Specimens
were tested for 7, 14 and 28 days and compared the results
obtained with conventional concrete.
Keywords – No Aggregate Concrete; Tensile characteristics;
Properties of No Aggregate Concrete; Elastic Modulus
INTRODUCTION
Concrete can be identified as the most commonly used
construction material on earth in the present context. With
the increasing demand for the natural resources in the
developing world construction industry finds it difficult to
acquire adequate composites to manufacture traditional
concrete. Therefore manufacturing durable concrete using
industry waste products will be beneficial and provide
solutions to the trending issues in the industry. When fine
and coarse aggregates are replaced completely in concrete
then it is called no aggregate concrete.
Since all the aggregates have been replaced with fly ash,
the density of NAC is lesser than the conventional concrete.
According to past research data density of a similar kind
concrete is around 1850 – 2000 kg/m3
[1]. This will address
many present construction issues which are mainly related
weight and durability. Also there could be considerable
savings in structural design and inputs. When aggregates are
not available in concrete it devoid the transition zone and
many durability issues would be addressed in one stroke [2].
Even the inert fly ash particles develop cohesive bond with
cement matrix making the ultimate NAC matrix close to
monolithic [3]. Based on previous experimental research
some beneficial effects have been reported that fly ash was
able to enhance the compressive strength when used as a
replacement material with low water cement ratio [4].
The main objective of this research is to identify tensile
characteristics of NAC. Therefore the paper focuses mainly
on how the tensile characteristics varies of this
unaccustomed material based on time and different mix
proportions. Though concrete has very low tensile capacity
compared to compression capacity it is difficult to isolate
concrete members from dynamic tensile stresses. This is a
crucial design parameter especially in structures such as
concrete dams, airfield runways, concrete roads and
pavements and other slabs. Therefore good understanding
about the tensile characteristics and tensile capacity will give
a broad insight on the load at which the concrete members
may crack. Cracking is a form of tension failure. Also the
elastic modulus for this material has also been identified so
complex numerical models can be developed using the
results.
Identifying the material used for the research and their
mechanical and physical properties have identified in the
Section 2. Section 3 explains the methodologies followed in
order to achieve the final objectives of the research. Section
4 discusses the results ascertained from the experiments and
a brief analysis on each result. Section 5 concludes the paper
while summarising all the results observed and suggesting
probable further developments to the research topic.
MATERIAL DESCRIPTION
Cement
OPC (grade 42.5) was used. It is manufactured in
compliance with Sri Lankan Standard SLS 107:2008 and
British Standard CEM I 42.5N of BS EN 197-1:2000.
Physical and chemical compositions of cement.
Density 3.15 g/cm3
Fineness 340 m2
/kg
Soundness 0.32 mm
Setting time (Initials) 125 min
Comp. strength at 2 days 30.8 MPa
at 28 days 58 MPa
Chemical compositions
CaO 64.5%
SiO2 20.5%
Al2O 3 5.7%
Fe2O 3 2.9%
MgO 1.27%
SO3 2.15%
Cl-
0.009%
Loss of ignition 3.0
D.D Nakandala (110379D)
Department of Civil Engineering
University of Moratuwa
Moratuwa, Sri Lanka
dulannakandala@gmail.com
2. Fine aggregate
Local river sand with a 5mm maximum size was used. It
conforms to BS 882.
Coarse aggregate
Crushed rock aggregate of 20mm nominal size were used.
It met the requirements of BS 882
Fly ash
Class F fly was used for the study and met requirements
of ASTM C 618
Properties and chemical compositions of fly ash
Density 2.16 g/cm3
Blaine fineness 3310 cm2/g
pH 4.6
Loss of ignition 4.0%
Chemical compositions
SiO2 62.4%
Al2O3 3.3%
Fe2O3 3.19%
K2O 1.38%
CaO 0.98%
MgO 0.55%
SO3 0.24%
Na2O 0.19%
Superplasticizer
A commercially available fourth generation
superplasticizer formulated specifically to give high range
water reduction with retarding effect for hot weather
construction was used. It conforms to the requirement of
ASTM C4g4 Type G, BS 5075 and SS320: 1987
METHODOLOGY
Material proportions for NAC
For normal concrete, BRE mix design procedure were
adopted to identify the mix proportions needed to gain grade
30 strength. Since no standard method is available for mix
design of NAC, the procedure followed was preparing
several trial mixes. This was done by assuming a density
initially and varying mix proportions (keeping the cement
quantity constant) till the mix get the assumed density. After
several trial mixes the appropriate mix proportions were
found as shown in table 1 and used it for test batch
preparations.
Table 1 Mix Proportions of Different Mixes
Mixing procedure
The normal concrete batch was mixed following the
general procedure where coarse aggregates were added first
and cement was added last. Then it was mixed till it form a
good paste. However this procedure was quite different when
it came to NAC mixing. In that mix, cement and fly ash was
mixed together first using shovel. Supercrete (Plasticizer)
was mixed with the measured water quantity. After mixing
fly ash and cement in the drum mixer without any
interruptions for few minutes 90% of the liquid mixture
(water and plasticizer) was added completely. Mixing was
continued till it form a good paste and the remaining liquid
mixture was added appropriately.
Specimen details
For this research four different batches were produced.
Those batches were namely normal concrete, NAC, 10%
cement increased NAC and 10% fly-ash increased NAC.
Variations in mix proportions were done in order to identify
the strength behavior in NAC. All those batches were tested
for 7, 14 and 28 days. Since splitting tensile strength were
tested it was used 150 mm x 300 mm cylinders for testing
purposes. To reduce the error margin 3 cylinders were casted
for each test and took the average. The mix designs of the
concretes are shown in the table 1.
Splitting tensile test
The present study mainly focuses on tensile properties
observed from splitting tensile test. The tests were performed
as shown in figure 1 at the ages outlined previously to
determine the relationships with tensile properties. This test
method consists of applying a diametral compressive force
along the length of cylindrical concrete at a prescribed rate
until failure occurs. ASTM standards [5] were followed as
stated during the testing period. Tensile strength of the
specimen (T) can be estimated from equation (1).
T = 2P/πld (1)
Where P is the applied load in kN, l is the length of the
specimen in meters and d is the diameter of the specimen in
meters.
Figure 1: Performing splitting tensile test
Normal
Concrete
(1 m3)
NAC (Mix 1)
1 m3
NAC (Mix
2)
10%
cement
increased
1 m3
NAC (Mix
3)
10% fly
ash
increased
1 m3
Cement 350 kg 350 kg 385 kg 315 kg
Coarse
Aggregates
1075 kg - - -
Fine
Aggregates
875 kg - - -
Fly Ash - 1400 kg 1365 kg 1540 kg
Supercrete 5.25 l 8.6 l 8.5 l 8.5 l
Water 300 l 300 l 328 l 335 l
3. Determining static modulus of elasticity
Since this is novel material it is essential to identify the
basic properties of the material. This will help for further
studies and to develop numerical models. In order to identify
static modulus of elasticity test procedure given in ASTM
C469 was followed. The cylindrical compressive strength
was calculated using ASTM Designation: C 39 before the
test. The cylindrical compressive strength value obtained
was 20.53 N/mm2
. Loads and readings of the dial gauge were
recorded as specified in the standard. Following equation (2)
was used to determine the static modulus of elasticity.
E =
(s2 – s1)
(ε2 – 0.000050)
(2)
E = Chord modulus of elasticity
s2 = Stress corresponding to 40% of the estimated ultimate
load or ultimate stress, based upon previously tested
specimens in accordance with ASTM Designation: C 39
s1 = Stress corresponding to a longitudinal strain of 0.000050
ε2 = Longitudinal strain corresponding to the s2 stress
ε1 = Strain 0.000050 and, therefore, does not appear in the
formula for E.
TEST RESULTS AND DISCUSSION
Tensile strength comparison between normal grade 30
concrete and NAC
From figure 2 and it is clear that the Normal grade 30
concrete is having higher tensile capacity compared to the
NAC which had same cement content. Both concrete types
showed an increase in strength with time but at the end of 28
days normal concrete gave a tensile strength of 3.07 MPa
where NAC gave only 2.36 MPa. The values obtained is an
average value of 3 specimens.
This difference may be due to the high brittle nature of NAC.
Brittleness is one of the governing factors in determining
tensile strength.
Variability of tensile strength with changes in mix
proportions in NAC
Since this is a novel material strength behavior is
unknown. To identify the strength behavior, different mix
proportions were tested. Keeping the original mix
proportions for NAC as the yardstick, percentage increase in
materials was done to the other two batches. However all
three batches showed lesser tensile capacities than the
normal concrete. In the second batch where 10% cement was
increased gave the highest tensile capacity with a strength of
2.45 MPa in 28days. In the third batch where 10% fly ash
was increased had very low tensile capacities where only
1.98 MPa gained after 28 days. All the 3 batches showed
increase in strength with time and this variation is visible in
figure 3. This strength increase in NAC with time can be
explained by referring to the improved microstructure in the
concrete. Use of finer particles for the aggregate leads to
densification of matrix and secondary reaction between fly
ash and CH in the transition zone also improves the
microstructure of the concrete.
This variation in strength with different mix proportions
is probably due to the level of unreacted fly ash content
available in the final concrete mix. In the second batch when
the cement was increased more fly ash might have reacted
with cement and gave better tensile capacity.
Reason for increase in strength with time can be explained
by the amount of CH and rate of reaction of fly ash with CH.
This is represented by cementing efficiency factor of fly ash
at the age.
Density variation in normal concrete and NAC
In the figure 4 it is clear that normal concrete has much
higher density compared to NAC. The density of normal
concrete was around 2400 kg/m3
where NAC had only a
density of 2100–2000 kg/m3
. This may be due to the
replacement of aggregates which have higher specific
gravity than fly ash. Densities of different batches in NAC
also had slight variations. Where NAC (batch 1) had much
higher density and NAC (batch 3) had the lowest density.
Densities reduce with time in all the scenarios and this is
probably due to moisture loss in concrete with time.
Figure 2: Tensile strength variation in normal concrete & NAC
Figure 3: Tensile Strength variation of different NACs
Figure 4: Density variation with time
4. Relationship with compressive strength and tensile
strength in NAC
Generally in concrete tensile strength is known to be
around 10% of the compressive strength. In this research
compressive strength of normal concrete was around 36.7
MPa and the tensile capacity was around 3.07 MPa which is
9% of compressive strength obtained. However this is
different when it comes to NAC. Because from the values
obtained tensile strength of no aggregate concrete was only
about 5%-6% of compressive strength of NAC. So compared
to normal concrete there is a considerable reduction in tensile
strength in NAC. This variation is illustrated in figure 5.
In NAC because of the fly ash substitution micro structure
of the material was enhanced. Because of this compressive
strengths increased. Also there is a better compaction in this
material which gives favorable results in compression.
However due to high brittleness of the material it has very
low tensile capacity compared to normal concrete. Since
there are no any aggregates the surface friction is also lesser
in NAC which might has led to low tensile capacity. Due to
these reasons ratio between tensile strength and compressive
strength of NAC is much lower than the value obtained in
normal concrete.
Properties of NAC
Some mechanical properties of NAC was identified
which will be helpful in future experiments and other
modelling activities. Using ASTM C469 it was found that
elastic modulus (E) of NAC is around 11.58 GPa. In normal
concrete (G30) this value was around 26 GPa. Also from the
results stress strain graph was developed as shown in figure
6.
Also from the obtained test results and visual
observations it was identified that the material is highly
brittle.
CONCLUSION
The present study aimed to obtain the tensile properties
of NAC. This paper describes splitting tensile strength and
Young’s modulus of NAC and also some behavioral patterns
in tensile strength of NAC under various conditions.
Tensile capacity of NAC is lesser than the tensile
capacity of normal concrete which has the same
cement content.
Tensile capacity of NAC can be increased by replacing
some amount of the fly ash with cement in the original
mix. If the tensile capacity has to be decreased then
cement should be replaced with fly ash.
Density of NAC is lower than the density of normal
concrete. Also the density values reduce with time.
Ratio between tensile strength and compressive
strength is lesser in NAC compared to normal
concrete. In NAC tensile strength is around 6% of
compressive strength but in normal concrete this value
is around 10%.
Young’s modulus of NAC (11 GPa) is lower than the
Young’s modulus of normal concrete (26 GPa).
Brittleness of NAC is higher than the brittleness of
normal concrete.
Workability and the setting time in NAC is higher than
the normal concrete.
Surface condition of NAC is better than normal concrete
and has a very smooth surface.
As a final note it is not recommended to use 100%
aggregate replaced concrete. However viable solution
would be partial replacement of fine aggregates.
REFERENCES
[1] Fahrizal Zulkarnain, Mahyuddin Ramli. Durability
performance of lightweight aggregate concrete for
housing construction. 2008.
[2] Clarke, J.L. (1993) Structural Lightweight
Aggregate Concrete (First Edition). Glasgow,
Blackie Academic & Professional, an imprint of
Chapman & Hall, Wester Cleddens Road, Bishop
Briggs.
[3] Bhanumathidas N & Kalidas N(2010). Irrational
concrete with rational performance. The institute of
solid waste research and ecological balance,
Vishakhapatnam.
[4] Hossain AB, Islam S, Copeland KD. Influence of
ultrafine fly ash on the shrinkage and cracking
tendency of concrete and the implications for bridge
decks.
[5] Standard test method for splitting tensile strength of
cylindrical concrete specimen. ASTM (C496)
Figure 5: Comparison between Compressive strength & Tensile
strength
Figure 6: Stress vs Strain graph