This document summarizes an experimental investigation into crack propagation and branching in lightly reinforced concrete beams. A total of six beams were cast in two series of varying depths (150mm and 200mm) but with the same width (100mm). Each series included one unreinforced beam and two beams reinforced with steel ratios between 0.25-0.6%. The aim was to observe the effect of beam depth and steel ratio on ductility by investigating crack branching. Testing of the samples was underway and the results would be used to understand flexural behavior and crack development in lightly reinforced concrete beams.
This document is a dissertation submitted by Shakeel Ahmad Bhat to fulfill requirements for a Masters degree in Construction Technology and Management. The dissertation investigates crack propagation and branching in lightly reinforced concrete beams through experimental testing. Six concrete beams of two different depths (150mm and 200mm) and reinforcement ratios (0.25-0.6%) will be tested to observe the effect on ductility. The testing aims to provide insight into the fracture process zone near cracks in reinforced concrete and improve understanding of cracking behavior.
International Journal of Engineering Research and DevelopmentIJERD Editor
Electrical, Electronics and Computer Engineering,
Information Engineering and Technology,
Mechanical, Industrial and Manufacturing Engineering,
Automation and Mechatronics Engineering,
Material and Chemical Engineering,
Civil and Architecture Engineering,
Biotechnology and Bio Engineering,
Environmental Engineering,
Petroleum and Mining Engineering,
Marine and Agriculture engineering,
Aerospace Engineering.
A Study on Effect of Sizes of aggregates on Steel Fiber Reinforced ConcreteIJERD Editor
Plain, unreinforced concrete is a brittle material, with a low tensile strength, limited ductility and
little resistance to cracking. In order to improve the inherent tensile strength of concrete there is a need of
multidirectional and closely spaced reinforcement, which can be provided in the form of randomly distributed
fibers. Steel fiber is one of the most commonly used fibers The present experimental study considers the effect
of aggregate size and steel fibers on the modulus of elasticity of concrete. Crimped steel fibers at volume
fraction of 0%.0.5%, 1.0% and 1.5% were used. Study on effect of volume fraction of fibers and change of
aggregate size on the modulus of elasticity of concrete was also deemed as an important part of present
experimental investigation. This work aims in studying the mechanical behavior of concrete in terms of modulus
of elasticity with the change of aggregate size reinforced with steel fibers of different series for M30 and M50
grade concretes. The results obtained show that the addition of steel fiber improves the modulus of elasticity of
concrete. It was also analyzed that by increasing the fiber volume fraction from 0%, to 1.5% there was a healthy
effect on modulus of elasticity of Steel Fiber Reinforced concrete.
Research Inventy : International Journal of Engineering and Scienceresearchinventy
Research Inventy : International Journal of Engineering and Science is published by the group of young academic and industrial researchers with 12 Issues per year. It is an online as well as print version open access journal that provides rapid publication (monthly) of articles in all areas of the subject such as: civil, mechanical, chemical, electronic and computer engineering as well as production and information technology. The Journal welcomes the submission of manuscripts that meet the general criteria of significance and scientific excellence. Papers will be published by rapid process within 20 days after acceptance and peer review process takes only 7 days. All articles published in Research Inventy will be peer-reviewed.
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.
IRJET - Performance of SFRC Beams under Combined State of Flexure, Direct...IRJET Journal
This document summarizes research on the performance of steel fiber reinforced concrete (SFRC) beams under combined states of flexure, direct compression, and shear. It describes an experimental study that tested SFRC beams with various fiber volume fractions (0%, 0.5%, 0.75%, 1.0%) under different compression loads (0, 50, 100, 125 kN). The study found that adding steel fibers increased the compressive strength, flexural strength, and shear strength of the concrete beams. Beams with higher fiber content performed better under the combined loading conditions compared to beams with lower or no fiber content. The document provides details on the materials, beam specimens, mixing, casting, curing, and testing methods used
Experimental study on behaviour of concrete using steel fiber as a tensile ma...KavinKumarR3
Concrete is widely used in all over the world. It gives a compression strength and when it is collaborate with the steel the tension strength is increased. Traditional reinforcement will takes time. So by using the steel fibers in the concrete it will gives the high strength and durability. The fiber will leads to compensate the weakness in the concrete. Steel fiber reinforced concrete (SFRC) is successfully used in the slabs, flooring, and even in beams. The formation has proved the high tensile strength when it added in the concrete.
This document summarizes an experimental study that investigated the influence of fusion bonded epoxy coated bars on the tension stiffening effect of self-compacting concrete. 18 direct tension test specimens were made with bar diameters of 8mm, 10mm, and 12mm and specimen lengths of either 40 or 50 times the bar diameter. The results showed that using epoxy coated bars reduced the tension stiffening effect of the self-compacting concrete by 9.4% to 32% compared to uncoated bars. Additionally, reducing the bar diameter from 12mm to 10mm improved the tension stiffening effect by 20-30%. Finally, the spacing of cracks was 7-18% greater when using epoxy coated bars in self
This document is a dissertation submitted by Shakeel Ahmad Bhat to fulfill requirements for a Masters degree in Construction Technology and Management. The dissertation investigates crack propagation and branching in lightly reinforced concrete beams through experimental testing. Six concrete beams of two different depths (150mm and 200mm) and reinforcement ratios (0.25-0.6%) will be tested to observe the effect on ductility. The testing aims to provide insight into the fracture process zone near cracks in reinforced concrete and improve understanding of cracking behavior.
International Journal of Engineering Research and DevelopmentIJERD Editor
Electrical, Electronics and Computer Engineering,
Information Engineering and Technology,
Mechanical, Industrial and Manufacturing Engineering,
Automation and Mechatronics Engineering,
Material and Chemical Engineering,
Civil and Architecture Engineering,
Biotechnology and Bio Engineering,
Environmental Engineering,
Petroleum and Mining Engineering,
Marine and Agriculture engineering,
Aerospace Engineering.
A Study on Effect of Sizes of aggregates on Steel Fiber Reinforced ConcreteIJERD Editor
Plain, unreinforced concrete is a brittle material, with a low tensile strength, limited ductility and
little resistance to cracking. In order to improve the inherent tensile strength of concrete there is a need of
multidirectional and closely spaced reinforcement, which can be provided in the form of randomly distributed
fibers. Steel fiber is one of the most commonly used fibers The present experimental study considers the effect
of aggregate size and steel fibers on the modulus of elasticity of concrete. Crimped steel fibers at volume
fraction of 0%.0.5%, 1.0% and 1.5% were used. Study on effect of volume fraction of fibers and change of
aggregate size on the modulus of elasticity of concrete was also deemed as an important part of present
experimental investigation. This work aims in studying the mechanical behavior of concrete in terms of modulus
of elasticity with the change of aggregate size reinforced with steel fibers of different series for M30 and M50
grade concretes. The results obtained show that the addition of steel fiber improves the modulus of elasticity of
concrete. It was also analyzed that by increasing the fiber volume fraction from 0%, to 1.5% there was a healthy
effect on modulus of elasticity of Steel Fiber Reinforced concrete.
Research Inventy : International Journal of Engineering and Scienceresearchinventy
Research Inventy : International Journal of Engineering and Science is published by the group of young academic and industrial researchers with 12 Issues per year. It is an online as well as print version open access journal that provides rapid publication (monthly) of articles in all areas of the subject such as: civil, mechanical, chemical, electronic and computer engineering as well as production and information technology. The Journal welcomes the submission of manuscripts that meet the general criteria of significance and scientific excellence. Papers will be published by rapid process within 20 days after acceptance and peer review process takes only 7 days. All articles published in Research Inventy will be peer-reviewed.
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.
IRJET - Performance of SFRC Beams under Combined State of Flexure, Direct...IRJET Journal
This document summarizes research on the performance of steel fiber reinforced concrete (SFRC) beams under combined states of flexure, direct compression, and shear. It describes an experimental study that tested SFRC beams with various fiber volume fractions (0%, 0.5%, 0.75%, 1.0%) under different compression loads (0, 50, 100, 125 kN). The study found that adding steel fibers increased the compressive strength, flexural strength, and shear strength of the concrete beams. Beams with higher fiber content performed better under the combined loading conditions compared to beams with lower or no fiber content. The document provides details on the materials, beam specimens, mixing, casting, curing, and testing methods used
Experimental study on behaviour of concrete using steel fiber as a tensile ma...KavinKumarR3
Concrete is widely used in all over the world. It gives a compression strength and when it is collaborate with the steel the tension strength is increased. Traditional reinforcement will takes time. So by using the steel fibers in the concrete it will gives the high strength and durability. The fiber will leads to compensate the weakness in the concrete. Steel fiber reinforced concrete (SFRC) is successfully used in the slabs, flooring, and even in beams. The formation has proved the high tensile strength when it added in the concrete.
This document summarizes an experimental study that investigated the influence of fusion bonded epoxy coated bars on the tension stiffening effect of self-compacting concrete. 18 direct tension test specimens were made with bar diameters of 8mm, 10mm, and 12mm and specimen lengths of either 40 or 50 times the bar diameter. The results showed that using epoxy coated bars reduced the tension stiffening effect of the self-compacting concrete by 9.4% to 32% compared to uncoated bars. Additionally, reducing the bar diameter from 12mm to 10mm improved the tension stiffening effect by 20-30%. Finally, the spacing of cracks was 7-18% greater when using epoxy coated bars in self
Effect of prism height on strength of reinforced hollow concrete block masonryeSAT Publishing House
IJRET : International Journal of Research in Engineering and Technology is an international peer reviewed, online journal published by eSAT Publishing House for the enhancement of research in various disciplines of Engineering and Technology. The aim and scope of the journal is to provide an academic medium and an important reference for the advancement and dissemination of research results that support high-level learning, teaching and research in the fields of Engineering and Technology. We bring together Scientists, Academician, Field Engineers, Scholars and Students of related fields of Engineering and Technology.
Micro Structure Amd Mechanical Properties of Nanoparticulate Wc/Al Metal Matr...IJRES Journal
The addition of reinforcement definitely changes mechanical behaviour of metal matrix composites (MMCs). Hence the objective of the work is to study the effect of nano WC particle content on the mechanical behaviour of Al alloy reinforced composites was studied by using optical microscopy, mechanical properties measurements and scanning electron microscope. The hardness, ultimate tensile strength, compression strength and young's modulus were found higher than those of control alloy. The dislocations which serve as heterogeneous nucleation sites for strengthening precipitates during subsequent solidification compared to control alloy. Higher density of dislocations and higher density of intermediate precipitates was observed.
This study investigated the compressive strength of reinforced concrete columns wrapped with different hybrid fiber reinforced polymer (FRP) configurations. Four 150x380mm concrete columns were tested: one unconfined control column and three wrapped with different combinations of glass, basalt, and jute FRP. The column wrapped with two layers each of basalt, glass, and jute FRP (CBGJ) achieved the highest compressive strength, reaching 1000kN and exceeding the unconfined column's strength by 25%. Analysis of the load-displacement and load-strain behaviors showed that the CBGJ wrapping configuration resulted in higher displacement and strain values compared to the other specimens. The results indicate that hybrid FRP wrapping can significantly
Experimental performance of flexural creep behavior of ferrocement slabeSAT Publishing House
IJRET : International Journal of Research in Engineering and Technology is an international peer reviewed, online journal published by eSAT Publishing House for the enhancement of research in various disciplines of Engineering and Technology. The aim and scope of the journal is to provide an academic medium and an important reference for the advancement and dissemination of research results that support high-level learning, teaching and research in the fields of Engineering and Technology. We bring together Scientists, Academician, Field Engineers, Scholars and Students of related fields of Engineering and Technology
Effect of Nano-Tio2addition on Mechanical Properties of Concrete and Corrosio...IJERA Editor
Concrete science is a multidisciplinary area of research where nanotechnology potentially offers the opportunity to enhance the understanding of concrete behavior, to engineer its properties and to lower production and ecological cost of construction materials. The main objective of this research was to evaluate the effect of nanoTiO2on compressive strength,bond strength and corrosion behavior of reinforcement bars. It has been found that the compressive strength, bond strength and corrosion resistance was increased with increasing nano-TiO2to 1.5wt. % as replacement of cement. Beyond this value, these properties decrease.
Strengthening of reinforced concrete beam using steel fiber at different dept...eSAT Journals
Abstract
This paper presents the results of an experimental investigation for enhancing the shear and ultimate strength capacities of reinforced concrete (RC) beams using steel fiber at different depths. Ultimate loads, load-deflection curves, cracking and crushing patterns have been compared with those of the RC beams without steel fiber henceforth noted as controlled beam. A total of four sets of experiments each having three concrete beams, one set control beam and three sets with randomly distributed discrete steel fiber at different depths henceforth noted as fiber reinforced concrete (FRC) beam, were performed to determine the most economical structure in the perspective of ultimate strength and shear capacity. From the test results, it was found that incorporation of steel fiber in RC beams have shown to be effective in enhancing the shear strength capacity. It has also been observed that the strength increases with the use of varying depth of steel fiber. Beam strengthened using this scheme has shown 20% increase in shear strength and ultimate load in comparison to controlled beam.
Key Words: Reinforced Concrete Beams, High Strength Concrete, Steel fibers, strengthening
This document summarizes a study on using crumb rubber from wasted tires to develop high-performance multi-layer bulletproof concrete panels. The proposed panel uses a double layer of rubberized concrete and steel fiber reinforced concrete (SFRC). Testing showed that single layers of rubberized concrete or SFRC did not stop bullets, while the double layer configuration was able to stop bullets without penetration. Analysis of acceleration and displacement values indicated that the rubberized concrete layer absorbed impact energy and reduced stresses on the panel compared to SFRC alone. Therefore, partially replacing the front layer of bulletproof panels with rubberized concrete enhances performance while providing an application for recycled tire rubber.
IRJET- Effect of Fiber Addition on Mechanical Properties of ConcreteIRJET Journal
The document discusses the effect of adding different types and amounts of steel fibers and glass fibers on the mechanical properties of concrete. Tests were conducted on concrete specimens with 0%, 1%, 2%, and 3% volume fractions of steel fibers to measure their compressive strength and split tensile strength after 28 days. The results showed that compressive strength and split tensile strength increased as the steel fiber content increased, with the 3% fiber volume fraction specimens exhibiting the highest strengths. Similar tests also examined the effect of 0%, 2%, 4%, and 6% glass fiber volume fractions. Both steel and glass fibers improved the mechanical properties of concrete compared to normal concrete without fibers.
Axial Capacity Enhancement of CFRP Confined Columns Made of Steel Fiber Reinf...IOSRJMCE
Results of the experimental study on the axial compressive behavior of steel fiber reinforced concrete (SFRC) wrapped with fiber reinforced polymer (FRP) have been presented in this paper. A total of 18 concrete cylinders were tested under axial compression. The effects of steel fiber parameters were investigated which includes fiber aspect ratio (AR) and fiber volume fraction (VF). The concrete cylinders were divided into groups of confined and unconfined ones. In accordance with previous study, it was found that, FRP confined cylinders showed greater axial stress than that of unconfined specimens. Although the presence of steel fiber increases the peak axial stresses for both confined and unconfined group of specimens, but no significant change of peak axial stress (and peak strain) has been observed in both confined and unconfined group due to increase of fiber volume ratio. But with the increase of fiber aspect ratio, the peak axial stresses of both unconfined and FRPconfined cylinders were found to slightly decrease. It was also observed that, concrete specimens reinforced with internal steel fiber absorbed much higher energy than that of unreinforced ones.
Waste Metal For Improving Concrete Performance And Utilisation As An Alternat...IJERA Editor
Waste material disposal is considered as a difficult issue to adopt in current world. Waste metal, which has been
recognised as a major problem in the environment and resource deficiency, could have important implications in
the concrete construction industries. Waste metal utilisation in construction of reinforced cement concrete (RCC)
works is immerging in recent time. Construction industries are looking for cost effective structural materials and
utilisation of renewable materials. Metal waste such as chips of tin, still and other metal fragments which is
abandoned and spread in the environment could be utilize as a replacement of traditional steel reinforcement bar
in the RCC. In this experiment, three different types of waste metal have been compared with commercial 40, 60
and 72 graded steel reinforcement bar. Compressive strength class of C25 concrete was used in the experiment
and mechanical properties of concrete incorporating different waste metal were investigated in the first stage.
Finally, three-point bend test on short beam was performed to compare their performances. Smaller metal
fragments has shown better performance through micro crack bridging in concrete during loading stage and
hence better than ordinary reinforcement concrete structure in some extent.
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
IRJET- Improvement of Performance of Concrete using Straight and 3D Steel...IRJET Journal
This document presents the results of a study on the effects of adding different types of steel fibers to concrete. Straight steel fibers, single closed loop fibers, and double closed loop fibers were added to concrete mixes in amounts from 0.5% to 2% by weight of cement. Specimens were tested to determine their compressive strength, split tensile strength, and flexural strength. It was found that the addition of steel fibers increased the mechanical properties of concrete up to an optimal fiber content of 1-1.5%. Double closed loop fibers provided the best improvement to strength, increasing compressive strength by up to 42.6% and split tensile strength by up to 62.4% compared to plain concrete. The study
The document describes an experimental study that evaluated the flexural behavior of steel fiber reinforced high strength self-compacting concrete slabs. Six concrete slabs were tested with varying concrete types (ordinary, self-compacting, high strength self-compacting) and steel fiber volume fractions (0%, 0.75%, 1.5%). Test results found that using self-compacting concrete and adding steel fibers improved flexural resistance and led to more ductile failure. The high strength self-compacting concrete slab with 1.5% steel fibers showed the highest ultimate load capacity, an 18.8% increase over the non-fiber slab. A finite element analysis was able to reasonably model the slab test results.
IRJET- State of Art Review of Experimental Pull Out TestsIRJET Journal
This document summarizes experimental pull-out tests that have been conducted from 1982 to 2018 to evaluate the bond-slip properties between steel reinforcement bars and concrete. It reviews 12 studies that tested specimens with varying bar diameters, concrete strengths, embedment lengths, and under monotonic and cyclic loading. The studies measured bond stress-slip response and failure modes. In general, test results showed that bond strength increases with smaller bar diameter, higher concrete strength, and confinement. Cyclic loading degrades bond strength and stiffness compared to monotonic loading. Splitting was a common failure mode, while pullout occurred in confined specimens.
This literature review summarizes several studies on slurry erosion performance and resistance of various coated and treated steels. Several studies investigated the effect of parameters like particle size, speed, concentration, and impact angle on erosion rate. Coatings like WC-Co, Cr2O3, and Al2O3 were found to improve erosion resistance compared to uncoated steels. Laser surface treatments using powders also increased hardness and erosion resistance. Erosion mechanisms for coated materials included cracking and removal of material, while uncoated steels experienced plastic deformation and cutting.
1) An experimental study tested the shear performance of hybrid bridge girders with ultra-high performance concrete (UHPC) in the critical shear spans near supports and normal high-strength concrete (HSC) with steel stirrups in the midspan.
2) Two hybrid beams were constructed with UHPC in the critical shear spans without transverse reinforcement and HSC with steel stirrups in the midspan.
3) The hybrid beams were tested at varying shear span-to-depth ratios and showed higher ultimate shear resistance and energy absorption compared to beams with steel or carbon fiber reinforced polymer stirrups. The hybrid design allowed for optimal use of expensive UHPC.
“Influence of particle index of coarse aggregate and its influences on proper...eSAT Publishing House
IJRET : International Journal of Research in Engineering and Technology is an international peer reviewed, online journal published by eSAT Publishing House for the enhancement of research in various disciplines of Engineering and Technology. The aim and scope of the journal is to provide an academic medium and an important reference for the advancement and dissemination of research results that support high-level learning, teaching and research in the fields of Engineering and Technology. We bring together Scientists, Academician, Field Engineers, Scholars and Students of related fields of Engineering and Technology.
This document presents an experimental and analytical study comparing the structural behavior of composite concrete slabs with profiled steel decking. 18 full-scale slab specimens were tested under different shear span lengths to evaluate the longitudinal shear bond strength between the concrete and steel deck. The experimental results were compared to analytical calculations using the m-k method and partial shear connection method from Eurocode 4. The m-k method was found to provide a more conservative estimate of load-carrying capacity than the partial shear connection method, with generally good agreement between experimental and analytical values.
Serviceability behavior of Reinforcement Concrete beams with polypropylene an...IJERA Editor
Serviceability Limit States (SLS) may lead to the design of concrete elements internally reinforced with Fiber Reinforced Polymer (FRP).In many types of concrete structure loss the serviceability due to wide cracks, number of cracks or large deflection is not uncommon behaviour in concrete structures or concrete beams.The flexural ductility affects the serviceability deflection of RC beams once flexural cracking take place.Imprvement will be focused on the use of polypropilene fibres , which is the subject of thispaper. The performance of concrete with fibers is judged by the flexural toughness obtained by load-deflection curves. The flexural toughness of concrete is depend on different types of fibersin use.Its tougness will be reperesent in the behaviour of RC memebres at failure. Sometimes, it is difficult to use the flexural toughness to judge the behavior of concrete structures under service load. The result of cracking on concrete beam due to the applied load and the method of loading to monitor and check the performance of concrete with different types of fiber arediscussed in this paper. The reductionin the dimension of cracks and the effect of energy disipations of polypropilene fibres will be the main aim of this research work.
1. The document summarizes a student project on modeling steel fiber reinforced concrete. It includes an abstract, literature review, methodology, applications, expected outcomes, and expected conclusions.
2. The project involves performing tests on steel fiber reinforced concrete and comparing the results to normal concrete for properties like compressive strength, split tension, and flexural strength.
3. The literature review covers previous research showing that adding steel fibers improves properties like tensile strength, ductility, crack resistance, fatigue resistance, and energy absorption of concrete.
Concrete made with Portland cement has certain characteristics: it is relatively strong in compression but weak
in tension and tends to be brittle. These two weaknesses have limited its use. Another fundamental weakness of
concrete is that cracks start to form as soon as concrete is placed and before it has properly hardened. These
cracks are major cause of weakness in concrete particularly in large on site applications leading to subsequent
fracture and failure and general lack of durability
This study uses explicit finite element analysis to predict the behavior of fiber-reinforced polymer (FRP) composite grid reinforced concrete beams subjected to four-point bending. The finite element models accurately captured the load-deflection behavior observed experimentally. A substructure model was also developed to analyze stresses in the longitudinal reinforcement at failure. This led to a proposed analysis procedure that accounts for different failure modes, providing conservative predictions of load capacity.
Effect of prism height on strength of reinforced hollow concrete block masonryeSAT Publishing House
IJRET : International Journal of Research in Engineering and Technology is an international peer reviewed, online journal published by eSAT Publishing House for the enhancement of research in various disciplines of Engineering and Technology. The aim and scope of the journal is to provide an academic medium and an important reference for the advancement and dissemination of research results that support high-level learning, teaching and research in the fields of Engineering and Technology. We bring together Scientists, Academician, Field Engineers, Scholars and Students of related fields of Engineering and Technology.
Micro Structure Amd Mechanical Properties of Nanoparticulate Wc/Al Metal Matr...IJRES Journal
The addition of reinforcement definitely changes mechanical behaviour of metal matrix composites (MMCs). Hence the objective of the work is to study the effect of nano WC particle content on the mechanical behaviour of Al alloy reinforced composites was studied by using optical microscopy, mechanical properties measurements and scanning electron microscope. The hardness, ultimate tensile strength, compression strength and young's modulus were found higher than those of control alloy. The dislocations which serve as heterogeneous nucleation sites for strengthening precipitates during subsequent solidification compared to control alloy. Higher density of dislocations and higher density of intermediate precipitates was observed.
This study investigated the compressive strength of reinforced concrete columns wrapped with different hybrid fiber reinforced polymer (FRP) configurations. Four 150x380mm concrete columns were tested: one unconfined control column and three wrapped with different combinations of glass, basalt, and jute FRP. The column wrapped with two layers each of basalt, glass, and jute FRP (CBGJ) achieved the highest compressive strength, reaching 1000kN and exceeding the unconfined column's strength by 25%. Analysis of the load-displacement and load-strain behaviors showed that the CBGJ wrapping configuration resulted in higher displacement and strain values compared to the other specimens. The results indicate that hybrid FRP wrapping can significantly
Experimental performance of flexural creep behavior of ferrocement slabeSAT Publishing House
IJRET : International Journal of Research in Engineering and Technology is an international peer reviewed, online journal published by eSAT Publishing House for the enhancement of research in various disciplines of Engineering and Technology. The aim and scope of the journal is to provide an academic medium and an important reference for the advancement and dissemination of research results that support high-level learning, teaching and research in the fields of Engineering and Technology. We bring together Scientists, Academician, Field Engineers, Scholars and Students of related fields of Engineering and Technology
Effect of Nano-Tio2addition on Mechanical Properties of Concrete and Corrosio...IJERA Editor
Concrete science is a multidisciplinary area of research where nanotechnology potentially offers the opportunity to enhance the understanding of concrete behavior, to engineer its properties and to lower production and ecological cost of construction materials. The main objective of this research was to evaluate the effect of nanoTiO2on compressive strength,bond strength and corrosion behavior of reinforcement bars. It has been found that the compressive strength, bond strength and corrosion resistance was increased with increasing nano-TiO2to 1.5wt. % as replacement of cement. Beyond this value, these properties decrease.
Strengthening of reinforced concrete beam using steel fiber at different dept...eSAT Journals
Abstract
This paper presents the results of an experimental investigation for enhancing the shear and ultimate strength capacities of reinforced concrete (RC) beams using steel fiber at different depths. Ultimate loads, load-deflection curves, cracking and crushing patterns have been compared with those of the RC beams without steel fiber henceforth noted as controlled beam. A total of four sets of experiments each having three concrete beams, one set control beam and three sets with randomly distributed discrete steel fiber at different depths henceforth noted as fiber reinforced concrete (FRC) beam, were performed to determine the most economical structure in the perspective of ultimate strength and shear capacity. From the test results, it was found that incorporation of steel fiber in RC beams have shown to be effective in enhancing the shear strength capacity. It has also been observed that the strength increases with the use of varying depth of steel fiber. Beam strengthened using this scheme has shown 20% increase in shear strength and ultimate load in comparison to controlled beam.
Key Words: Reinforced Concrete Beams, High Strength Concrete, Steel fibers, strengthening
This document summarizes a study on using crumb rubber from wasted tires to develop high-performance multi-layer bulletproof concrete panels. The proposed panel uses a double layer of rubberized concrete and steel fiber reinforced concrete (SFRC). Testing showed that single layers of rubberized concrete or SFRC did not stop bullets, while the double layer configuration was able to stop bullets without penetration. Analysis of acceleration and displacement values indicated that the rubberized concrete layer absorbed impact energy and reduced stresses on the panel compared to SFRC alone. Therefore, partially replacing the front layer of bulletproof panels with rubberized concrete enhances performance while providing an application for recycled tire rubber.
IRJET- Effect of Fiber Addition on Mechanical Properties of ConcreteIRJET Journal
The document discusses the effect of adding different types and amounts of steel fibers and glass fibers on the mechanical properties of concrete. Tests were conducted on concrete specimens with 0%, 1%, 2%, and 3% volume fractions of steel fibers to measure their compressive strength and split tensile strength after 28 days. The results showed that compressive strength and split tensile strength increased as the steel fiber content increased, with the 3% fiber volume fraction specimens exhibiting the highest strengths. Similar tests also examined the effect of 0%, 2%, 4%, and 6% glass fiber volume fractions. Both steel and glass fibers improved the mechanical properties of concrete compared to normal concrete without fibers.
Axial Capacity Enhancement of CFRP Confined Columns Made of Steel Fiber Reinf...IOSRJMCE
Results of the experimental study on the axial compressive behavior of steel fiber reinforced concrete (SFRC) wrapped with fiber reinforced polymer (FRP) have been presented in this paper. A total of 18 concrete cylinders were tested under axial compression. The effects of steel fiber parameters were investigated which includes fiber aspect ratio (AR) and fiber volume fraction (VF). The concrete cylinders were divided into groups of confined and unconfined ones. In accordance with previous study, it was found that, FRP confined cylinders showed greater axial stress than that of unconfined specimens. Although the presence of steel fiber increases the peak axial stresses for both confined and unconfined group of specimens, but no significant change of peak axial stress (and peak strain) has been observed in both confined and unconfined group due to increase of fiber volume ratio. But with the increase of fiber aspect ratio, the peak axial stresses of both unconfined and FRPconfined cylinders were found to slightly decrease. It was also observed that, concrete specimens reinforced with internal steel fiber absorbed much higher energy than that of unreinforced ones.
Waste Metal For Improving Concrete Performance And Utilisation As An Alternat...IJERA Editor
Waste material disposal is considered as a difficult issue to adopt in current world. Waste metal, which has been
recognised as a major problem in the environment and resource deficiency, could have important implications in
the concrete construction industries. Waste metal utilisation in construction of reinforced cement concrete (RCC)
works is immerging in recent time. Construction industries are looking for cost effective structural materials and
utilisation of renewable materials. Metal waste such as chips of tin, still and other metal fragments which is
abandoned and spread in the environment could be utilize as a replacement of traditional steel reinforcement bar
in the RCC. In this experiment, three different types of waste metal have been compared with commercial 40, 60
and 72 graded steel reinforcement bar. Compressive strength class of C25 concrete was used in the experiment
and mechanical properties of concrete incorporating different waste metal were investigated in the first stage.
Finally, three-point bend test on short beam was performed to compare their performances. Smaller metal
fragments has shown better performance through micro crack bridging in concrete during loading stage and
hence better than ordinary reinforcement concrete structure in some extent.
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
IRJET- Improvement of Performance of Concrete using Straight and 3D Steel...IRJET Journal
This document presents the results of a study on the effects of adding different types of steel fibers to concrete. Straight steel fibers, single closed loop fibers, and double closed loop fibers were added to concrete mixes in amounts from 0.5% to 2% by weight of cement. Specimens were tested to determine their compressive strength, split tensile strength, and flexural strength. It was found that the addition of steel fibers increased the mechanical properties of concrete up to an optimal fiber content of 1-1.5%. Double closed loop fibers provided the best improvement to strength, increasing compressive strength by up to 42.6% and split tensile strength by up to 62.4% compared to plain concrete. The study
The document describes an experimental study that evaluated the flexural behavior of steel fiber reinforced high strength self-compacting concrete slabs. Six concrete slabs were tested with varying concrete types (ordinary, self-compacting, high strength self-compacting) and steel fiber volume fractions (0%, 0.75%, 1.5%). Test results found that using self-compacting concrete and adding steel fibers improved flexural resistance and led to more ductile failure. The high strength self-compacting concrete slab with 1.5% steel fibers showed the highest ultimate load capacity, an 18.8% increase over the non-fiber slab. A finite element analysis was able to reasonably model the slab test results.
IRJET- State of Art Review of Experimental Pull Out TestsIRJET Journal
This document summarizes experimental pull-out tests that have been conducted from 1982 to 2018 to evaluate the bond-slip properties between steel reinforcement bars and concrete. It reviews 12 studies that tested specimens with varying bar diameters, concrete strengths, embedment lengths, and under monotonic and cyclic loading. The studies measured bond stress-slip response and failure modes. In general, test results showed that bond strength increases with smaller bar diameter, higher concrete strength, and confinement. Cyclic loading degrades bond strength and stiffness compared to monotonic loading. Splitting was a common failure mode, while pullout occurred in confined specimens.
This literature review summarizes several studies on slurry erosion performance and resistance of various coated and treated steels. Several studies investigated the effect of parameters like particle size, speed, concentration, and impact angle on erosion rate. Coatings like WC-Co, Cr2O3, and Al2O3 were found to improve erosion resistance compared to uncoated steels. Laser surface treatments using powders also increased hardness and erosion resistance. Erosion mechanisms for coated materials included cracking and removal of material, while uncoated steels experienced plastic deformation and cutting.
1) An experimental study tested the shear performance of hybrid bridge girders with ultra-high performance concrete (UHPC) in the critical shear spans near supports and normal high-strength concrete (HSC) with steel stirrups in the midspan.
2) Two hybrid beams were constructed with UHPC in the critical shear spans without transverse reinforcement and HSC with steel stirrups in the midspan.
3) The hybrid beams were tested at varying shear span-to-depth ratios and showed higher ultimate shear resistance and energy absorption compared to beams with steel or carbon fiber reinforced polymer stirrups. The hybrid design allowed for optimal use of expensive UHPC.
“Influence of particle index of coarse aggregate and its influences on proper...eSAT Publishing House
IJRET : International Journal of Research in Engineering and Technology is an international peer reviewed, online journal published by eSAT Publishing House for the enhancement of research in various disciplines of Engineering and Technology. The aim and scope of the journal is to provide an academic medium and an important reference for the advancement and dissemination of research results that support high-level learning, teaching and research in the fields of Engineering and Technology. We bring together Scientists, Academician, Field Engineers, Scholars and Students of related fields of Engineering and Technology.
This document presents an experimental and analytical study comparing the structural behavior of composite concrete slabs with profiled steel decking. 18 full-scale slab specimens were tested under different shear span lengths to evaluate the longitudinal shear bond strength between the concrete and steel deck. The experimental results were compared to analytical calculations using the m-k method and partial shear connection method from Eurocode 4. The m-k method was found to provide a more conservative estimate of load-carrying capacity than the partial shear connection method, with generally good agreement between experimental and analytical values.
Serviceability behavior of Reinforcement Concrete beams with polypropylene an...IJERA Editor
Serviceability Limit States (SLS) may lead to the design of concrete elements internally reinforced with Fiber Reinforced Polymer (FRP).In many types of concrete structure loss the serviceability due to wide cracks, number of cracks or large deflection is not uncommon behaviour in concrete structures or concrete beams.The flexural ductility affects the serviceability deflection of RC beams once flexural cracking take place.Imprvement will be focused on the use of polypropilene fibres , which is the subject of thispaper. The performance of concrete with fibers is judged by the flexural toughness obtained by load-deflection curves. The flexural toughness of concrete is depend on different types of fibersin use.Its tougness will be reperesent in the behaviour of RC memebres at failure. Sometimes, it is difficult to use the flexural toughness to judge the behavior of concrete structures under service load. The result of cracking on concrete beam due to the applied load and the method of loading to monitor and check the performance of concrete with different types of fiber arediscussed in this paper. The reductionin the dimension of cracks and the effect of energy disipations of polypropilene fibres will be the main aim of this research work.
1. The document summarizes a student project on modeling steel fiber reinforced concrete. It includes an abstract, literature review, methodology, applications, expected outcomes, and expected conclusions.
2. The project involves performing tests on steel fiber reinforced concrete and comparing the results to normal concrete for properties like compressive strength, split tension, and flexural strength.
3. The literature review covers previous research showing that adding steel fibers improves properties like tensile strength, ductility, crack resistance, fatigue resistance, and energy absorption of concrete.
Concrete made with Portland cement has certain characteristics: it is relatively strong in compression but weak
in tension and tends to be brittle. These two weaknesses have limited its use. Another fundamental weakness of
concrete is that cracks start to form as soon as concrete is placed and before it has properly hardened. These
cracks are major cause of weakness in concrete particularly in large on site applications leading to subsequent
fracture and failure and general lack of durability
This study uses explicit finite element analysis to predict the behavior of fiber-reinforced polymer (FRP) composite grid reinforced concrete beams subjected to four-point bending. The finite element models accurately captured the load-deflection behavior observed experimentally. A substructure model was also developed to analyze stresses in the longitudinal reinforcement at failure. This led to a proposed analysis procedure that accounts for different failure modes, providing conservative predictions of load capacity.
Effects of Hybrid Steel Fibers on the Mechanical Properties of Steel Fiber Re...IRJET Journal
This document discusses a study on the effects of adding different types of steel fibers on the mechanical properties of steel fiber reinforced concrete. Three types of steel fibers were investigated: straight steel fibers, hooked steel fibers, and crimped steel fibers. Concrete cubes, cylinders, and prisms containing varying percentages (1%, 2%, 3%) of each fiber type were tested to determine their compressive strength, split tensile strength, and flexural strength at different ages. The results showed that compressive strength increased up to 2% fiber content for all fiber types compared to plain concrete. Specifically, the compressive strength of concrete with 2% crimped steel fibers exhibited a 16.92% increase over the control concrete and other fiber mixtures
This document describes a student project to determine the compressive strength of concrete with the addition of steel nails. It includes the title page, table of contents, list of tables and figures, and the introduction chapter. The introduction provides background on fiber reinforced concrete and the objectives of studying how steel nail additions affect compressive strength over time. The project involved casting concrete cylinders with varying percentages of steel nail replacement and testing them after 3, 7, 14, and 28 days to analyze the results.
The document summarizes an experiment comparing pre-stressed/post-tensioned reinforcement to traditional steel reinforcement in concrete slabs. Two slabs were fabricated - a post-tensioned slab with 3/4" threaded rod and a rebar reinforced slab with #4 rebar. Material properties were tested, including concrete compressive strength from cylinders. The post-tensioned slab resisted 3.135 kips before cracking compared to 1.200 kips for the rebar slab. Post-tensioning doubled the load at cracking and increased ultimate strength by 1.2x. While post-tensioning increased cracking load and strength, it reduced ductility compared to the rebar slab. The results show post-tensioning can
This study proposes a theoretical model to predict the flexural capacity of steel fibre-reinforced concrete beams based on laboratory testing and analysis. Steel fibres were found to improve the ductility and toughness of high-strength concrete by increasing displacement at failure. A relationship between steel fibre volume and predicted moment capacity of beams was established based on a proposed flexural analysis method. However, no consistent relationship between fibre volume and concrete compressive strength was identified. The model has the potential to allow for earlier consideration of steel fibres in structural design compared to relying solely on testing of each mixture.
Behaviour of Steel Fibre Reinforced Concrete Beam under Cyclic LoadingIOSR Journals
Abstract: This paper describes the influence of steel fibre distribution on the ultimate strength of concrete
beams. An experimental & analytical investigation of the behaviour of concrete beams reinforced with
conventional steel bars and steel fibres under cyclic loading is presented. It is now well established that one of
the important properties of steel fibre reinforced concrete (SFRC) is its superior resistance to cracking and
crack propagation. As a result of this ability to arrest cracks, fibre composites possess increased extensibility
and tensile strength, both at first crack and at ultimate load and the fibres are able to hold the matrix together
even after extensive cracking. The net result of all these is to impart to the fibre composite pronounced post –
cracking ductility which is unheard of in ordinary concrete. The transformation from a brittle to a ductile type
of material would increase substantially the energy absorption characteristics of the fibre composite and its
ability to withstand repeatedly applied, shock or impact loading. Tests on conventionally reinforced concrete
beam specimens, containing steel fibres in different proportions, have been conducted to establish loaddeflection
curves. It was observed that SFRC beams showed enhanced properties compared to that of RC beams
with steel fibres. The experimental investigations are validated with the analytical studies carried out by finite
element models using ANSYS.
Keywords: Steel fiber, concrete, properties, crack, ductility, technology.
A Review On Strengthening Of RCC Square Columns with Reinforced Concrete Jack...IRJET Journal
This document reviews strengthening of reinforced concrete square columns with reinforced concrete jacketing. It discusses how RC jacketing leads to uniformly increased strength and stiffness of columns. The durability of the original column is also improved with RC jacketing compared to other techniques. The review examines factors that influence the bond between the column and jacket, such as surface preparation, dowel bars, and transverse reinforcement. It concludes that RC jacketing is an effective and economical retrofitting technique that increases load capacity and improves structural performance of columns.
The document summarizes research on the bond between concrete and steel reinforcement. It discusses how bond is achieved through adhesion, friction, and mechanical interlocking. It also examines different bond failure modes and factors that affect bond strength. The effects of steel fibers on bond are explored, finding they can increase toughness and confinement, but their benefit decreases with distance from the surface due to segregation. Bond testing methods are outlined, including pull-out, beam, and splice tests.
Review on Shear Strengthening of Rc Deep Beams with OpeningsIRJET Journal
This document reviews research on strengthening reinforced concrete deep beams with openings. It discusses two approaches: internal strengthening by adding steel reinforcement near openings, and external strengthening by attaching fibre-reinforced polymer layers around openings. The review examines literature on testing different strengthening materials and configurations. It also investigates failure modes like debonding between fibre layers and concrete, and introduces mechanical anchoring systems to prevent debonding.
IJRET : International Journal of Research in Engineering and Technology is an international peer reviewed, online journal published by eSAT Publishing House for the enhancement of research in various disciplines of Engineering and Technology. The aim and scope of the journal is to provide an academic medium and an important reference for the advancement and dissemination of research results that support high-level learning, teaching and research in the fields of Engineering and Technology. We bring together Scientists, Academician, Field Engineers, Scholars and Students of related fields of Engineering and Technology.
Investigations on Properties of Concrete using Steel Fiber Reinforced as Part...ijtsrd
Scope of using alternate materials as partial replacement of Coarse Aggregate is being searched for Concrete without sacrificing strength or increasing strength from economical and other aspects like using industrial waste for its efficient use. Investigations were done on M 25grade concrete by replacing coarse aggregate partially by steel fiber to get maximum strength. This Study presents the satisfactory results on various strength tests of concrete containing steel fiber as a partial replacement of coarse aggregate and would help to resolve solid waste disposal problem. However, further research work is still necessary in order to have a more in depth understanding. Hitesh Malviya | Pratiksha Malviya ""Investigations on Properties of Concrete using Steel Fiber Reinforced as Partial Replacement of Coarse Aggregate"" Published in International Journal of Trend in Scientific Research and Development (ijtsrd), ISSN: 2456-6470, Volume-3 | Issue-3 , April 2019, URL: https://www.ijtsrd.com/papers/ijtsrd22861.pdf
Paper URL: https://www.ijtsrd.com/engineering/civil-engineering/22861/investigations-on-properties-of-concrete-using-steel-fiber-reinforced-as-partial-replacement-of-coarse-aggregate/hitesh-malviya
Analysis and Design of PSC post te girderJesikaLalwani
1. The document discusses a project presentation on analyzing the effect of mix concrete on cold joints in prestressed girder bridges using finite element modeling. Cold joints form due to interruptions during concrete casting and can reduce structural integrity.
2. The objectives are to minimize stress concentrations at cold joints, determine the strength of remixed concrete grades M40-M50, and analyze deck slabs using ANSYS for conventional and remixed concrete.
3. The proposed methodology includes selecting element types, defining material properties, modeling geometry, meshing, applying loads, and discussing results. Tests will evaluate compressive strength, beam deflection, and cable profiles.
Analysis and Design of Post tensioned girderJesikaLalwani
1. The document discusses a project presentation on analyzing the effect of mix concrete on cold joints in prestressed girder bridges using finite element modeling. Cold joints form due to interruptions during concrete casting and can reduce structural integrity.
2. The objectives are to minimize stress concentrations at cold joints, determine the strength of remixed concrete grades from M40-M50, and analyze deck slabs using ANSYS for conventional and remixed concrete.
3. The proposed methodology includes selecting element types, defining material properties, modeling geometry, meshing, applying loads, and discussing results. Tests will evaluate compressive strength, beam deflection, and cable profiles.
IRJET- A Literature Review on Comparative Study of Deflection Behaviour o...IRJET Journal
This document provides a literature review that compares the deflection behavior of reinforced concrete (RCC) beams and prestressed concrete beams.
The review includes both analytical and experimental studies. Analytical studies found that RCC beams are more economical than prestressed beams for spans up to around 15-20 meters, but prestressed beams are superior for longer spans as they require smaller cross-sectional dimensions. Experimental studies showed prestressed beams had around 60% less deflection than comparable RCC beams. Studies of different concrete grades found the lowest concrete volume and steel quantity when using higher-strength concrete.
In general, the literature review concluded that RCC beams are suitable for shorter spans up to around 20 meters, but
The Study of Flexural and Ultimate Behavior of Ferrocement Lightweight Beam b...IRJET Journal
1. The study examines the flexural and ultimate behavior of ferrocement lightweight beams using autoclaved aerated concrete (AAC) blocks.
2. Six beams were tested - three reinforced concrete beams and three ferrocement beams. Testing involved applying a single point load until failure and recording the first crack load, ultimate load, and deflections.
3. Test results found that ferrocement beams gave early warning of failure through initial cracking compared to sudden failure in reinforced concrete beams. Ferrocement beams also experienced greater deflections than reinforced concrete beams under the same loads.
This document discusses various destructive and non-destructive tests used to evaluate the strength and durability of concrete. Destructive tests involve loading concrete specimens to failure, while non-destructive tests do not break the specimens. Some non-destructive tests discussed include the rebound hammer test, ultrasonic pulse velocity test, and pull-out testing. The results of non-destructive tests can provide estimates of concrete properties like strength, elasticity, and presence of cracks without damaging the structure.
Height and depth gauge linear metrology.pdfq30122000
Height gauges may also be used to measure the height of an object by using the underside of the scriber as the datum. The datum may be permanently fixed or the height gauge may have provision to adjust the scale, this is done by sliding the scale vertically along the body of the height gauge by turning a fine feed screw at the top of the gauge; then with the scriber set to the same level as the base, the scale can be matched to it. This adjustment allows different scribers or probes to be used, as well as adjusting for any errors in a damaged or resharpened probe.
Use PyCharm for remote debugging of WSL on a Windo cf5c162d672e4e58b4dde5d797...shadow0702a
This document serves as a comprehensive step-by-step guide on how to effectively use PyCharm for remote debugging of the Windows Subsystem for Linux (WSL) on a local Windows machine. It meticulously outlines several critical steps in the process, starting with the crucial task of enabling permissions, followed by the installation and configuration of WSL.
The guide then proceeds to explain how to set up the SSH service within the WSL environment, an integral part of the process. Alongside this, it also provides detailed instructions on how to modify the inbound rules of the Windows firewall to facilitate the process, ensuring that there are no connectivity issues that could potentially hinder the debugging process.
The document further emphasizes on the importance of checking the connection between the Windows and WSL environments, providing instructions on how to ensure that the connection is optimal and ready for remote debugging.
It also offers an in-depth guide on how to configure the WSL interpreter and files within the PyCharm environment. This is essential for ensuring that the debugging process is set up correctly and that the program can be run effectively within the WSL terminal.
Additionally, the document provides guidance on how to set up breakpoints for debugging, a fundamental aspect of the debugging process which allows the developer to stop the execution of their code at certain points and inspect their program at those stages.
Finally, the document concludes by providing a link to a reference blog. This blog offers additional information and guidance on configuring the remote Python interpreter in PyCharm, providing the reader with a well-rounded understanding of the process.
Discover the latest insights on Data Driven Maintenance with our comprehensive webinar presentation. Learn about traditional maintenance challenges, the right approach to utilizing data, and the benefits of adopting a Data Driven Maintenance strategy. Explore real-world examples, industry best practices, and innovative solutions like FMECA and the D3M model. This presentation, led by expert Jules Oudmans, is essential for asset owners looking to optimize their maintenance processes and leverage digital technologies for improved efficiency and performance. Download now to stay ahead in the evolving maintenance landscape.
DEEP LEARNING FOR SMART GRID INTRUSION DETECTION: A HYBRID CNN-LSTM-BASED MODELijaia
As digital technology becomes more deeply embedded in power systems, protecting the communication
networks of Smart Grids (SG) has emerged as a critical concern. Distributed Network Protocol 3 (DNP3)
represents a multi-tiered application layer protocol extensively utilized in Supervisory Control and Data
Acquisition (SCADA)-based smart grids to facilitate real-time data gathering and control functionalities.
Robust Intrusion Detection Systems (IDS) are necessary for early threat detection and mitigation because
of the interconnection of these networks, which makes them vulnerable to a variety of cyberattacks. To
solve this issue, this paper develops a hybrid Deep Learning (DL) model specifically designed for intrusion
detection in smart grids. The proposed approach is a combination of the Convolutional Neural Network
(CNN) and the Long-Short-Term Memory algorithms (LSTM). We employed a recent intrusion detection
dataset (DNP3), which focuses on unauthorized commands and Denial of Service (DoS) cyberattacks, to
train and test our model. The results of our experiments show that our CNN-LSTM method is much better
at finding smart grid intrusions than other deep learning algorithms used for classification. In addition,
our proposed approach improves accuracy, precision, recall, and F1 score, achieving a high detection
accuracy rate of 99.50%.
Software Engineering and Project Management - Software Testing + Agile Method...Prakhyath Rai
Software Testing: A Strategic Approach to Software Testing, Strategic Issues, Test Strategies for Conventional Software, Test Strategies for Object -Oriented Software, Validation Testing, System Testing, The Art of Debugging.
Agile Methodology: Before Agile – Waterfall, Agile Development.
Optimizing Gradle Builds - Gradle DPE Tour Berlin 2024Sinan KOZAK
Sinan from the Delivery Hero mobile infrastructure engineering team shares a deep dive into performance acceleration with Gradle build cache optimizations. Sinan shares their journey into solving complex build-cache problems that affect Gradle builds. By understanding the challenges and solutions found in our journey, we aim to demonstrate the possibilities for faster builds. The case study reveals how overlapping outputs and cache misconfigurations led to significant increases in build times, especially as the project scaled up with numerous modules using Paparazzi tests. The journey from diagnosing to defeating cache issues offers invaluable lessons on maintaining cache integrity without sacrificing functionality.
Generative AI Use cases applications solutions and implementation.pdfmahaffeycheryld
Generative AI solutions encompass a range of capabilities from content creation to complex problem-solving across industries. Implementing generative AI involves identifying specific business needs, developing tailored AI models using techniques like GANs and VAEs, and integrating these models into existing workflows. Data quality and continuous model refinement are crucial for effective implementation. Businesses must also consider ethical implications and ensure transparency in AI decision-making. Generative AI's implementation aims to enhance efficiency, creativity, and innovation by leveraging autonomous generation and sophisticated learning algorithms to meet diverse business challenges.
https://www.leewayhertz.com/generative-ai-use-cases-and-applications/
Accident detection system project report.pdfKamal Acharya
The Rapid growth of technology and infrastructure has made our lives easier. The
advent of technology has also increased the traffic hazards and the road accidents take place
frequently which causes huge loss of life and property because of the poor emergency facilities.
Many lives could have been saved if emergency service could get accident information and
reach in time. Our project will provide an optimum solution to this draw back. A piezo electric
sensor can be used as a crash or rollover detector of the vehicle during and after a crash. With
signals from a piezo electric sensor, a severe accident can be recognized. According to this
project when a vehicle meets with an accident immediately piezo electric sensor will detect the
signal or if a car rolls over. Then with the help of GSM module and GPS module, the location
will be sent to the emergency contact. Then after conforming the location necessary action will
be taken. If the person meets with a small accident or if there is no serious threat to anyone’s
life, then the alert message can be terminated by the driver by a switch provided in order to
avoid wasting the valuable time of the medical rescue team.
Supermarket Management System Project Report.pdfKamal Acharya
Supermarket management is a stand-alone J2EE using Eclipse Juno program.
This project contains all the necessary required information about maintaining
the supermarket billing system.
The core idea of this project to minimize the paper work and centralize the
data. Here all the communication is taken in secure manner. That is, in this
application the information will be stored in client itself. For further security the
data base is stored in the back-end oracle and so no intruders can access it.
1. “Experimental Investigation of Crack Propagation and
Branching in Lightly Reinforced Concrete beams”
A Dissertation
Submitted by
SHAKEELAHMAD BHAT
ROLL NO: 17320365026
In partial fulfillment of requirements for award of
Masters of technology
In
Construction Technology and Management
Under the guidance of
Er. Tarundeep Singh
Department of Civil Engineering
Desh Bhagat University Mandi Gobindgarh
1
2. 2
ACKNOWLEDGEMENT
I take this opportunity to express my profound gratitude and deep regards to my
guide Er. Tarundeep Singh for his exemplary guidance, monitoring and constant
encouragement throughout the course of this thesis. The blessing, help and guidance
given by him time to time shall carry me a long way in the journey of life on which I
am about to embark.
I am obliged to staff members of Department of Civil Engineering, Desh Bhagat
University, Gobindgarh for valuable information provided by them in their respective
fields. I am grateful for their cooperation during the period of my assignment.
Lastly, I thank almighty, my parents, dear ones and friends for their constant
encouragement without which assignment would not be possible.
Shakeel Ahmad Bhat
Roll. No. 17320365026
3. 3
Abstract
Concrete is a quasi-brittle material that has a weak tensile strength in comparison to its
compressive strength. Due to the low tensile strength of concrete, it is common to use concrete
with reinforcement to carry the tensile stresses. As a consequence, the presence of reinforcement
affects the crack development and crack propagation in reinforced concrete. Developing cracking
evaluation methods is important for the safety assessment and renovation of existing
infrastructure. An improved understanding of concrete cracking is an implicit requirement to
achieve this aim. The main aim of this project is to investigate the nature of fracture in reinforced
concrete. Relatively few fracture-oriented experimental studies have been conducted on reinforced
concrete. An experimental investigation was therefore undertaken to explore the cracking process
in lightly reinforced concrete (RC) beams and to observe the details of the localized fracture
process zone development. More specifically, the aim was to observe the effect of beam depth
(150 mm and200 mm) and steel reinforcement ratio (0.25-0.6%) on ductility through the
investigation of crack branching. A total of six beams were cast in two series of two sizes (depths of
150 and 200 mm and lengths of 1000mm and 1200 mm respectively) keeping the width same (100
mm) for all the beams Each of the series includes one unreinforced and two reinforced beams.
Furthermore the testing of samples is under process and after successful completion of tests a
conclusion will be drawn and a relationship will also be set out for future use.
4. 4
CONTENTS
Chapter 1…………………………………………………………………………………
INTRODUCTION….……………………………………………………………………..
1.1 GENERAL……………………………………………………………………………
1.2 BACKGROUND AND SCOPE………………………………………………………
1.3 OBJECTIVE………………………………………………………………………….
Chapter 2…………………………………………………………………………………
LITERATURE REVIEW……………………………………………………………………
Chapter 3…………………………………………………………………………………….
3.2 METHODOLOGY IN DETAIL………………………………………………………
Chapter 4……………………………………………………………………………………
EXPERIMENTAL INVESTIGATION…………………………………………………….
1. MATERIAL PROPERTIE
1. CEMENT
2. GRADATION OF FINE AGGREGATES. 17
3. CONCRETE MIX...
4. REINFORCEMENT STEEL
5. DETAILING OF REINFORCEMENT IN BEAMSs
6. FORMWORK FOR BEAMS
7. EXPERIMENTAL SETUP
8. CRACK DETECTION MICROSCOPE.
5. 5
List of Figures
Fig.1.1 :( a) fracture process zone (b) closure stresses (e) cracks in concrete (courtesy; Fracture
mechanics by E.E Gdoutous)
Fig.1.2: Flexure crack of beam.
Fig.4. 1: Gradation curve of sand obtained from sieve analysis in lab.
Fig.4. 2: Cube failure under compression test.
Fig.4. 3: (a) Steel test specimen tested in UTM (b) Steel test specimen after failure.
Fig.4. 4: Reinforcement steel used in beam.
Fig.4. 5: Moulds for beams.
Fig.4. 6: Insulation foam at center for notch provision.
Fig.4. 7: Casting of beams.
Fig.4. 8: Test specimen layout.
Fig.4. 9: Test set up of Three Point Loading frame.
Fig.4. 10: Crack detection microscope.
Fig.4.11: Flexure crack seen through crack microscope.
List of Tables
Table 4.1: Readings for standard consistency test. Table 4.2: Sieve analysis of sand.
Table 4.3: Sieve Analysis of Coarse Aggregate.
Table 4.4: Concrete mix (M 30)
Table 4.5: Cube strength under compression tests.
Table 4.6: Tensile strength of reinforcing steel bar. Table 4.7: Details of test specimens.
6. 6
Chapter I
INTRODUCTION
1.1 GENERAL
Concrete is a quasi-brittle material that has a relatively weak tensile strength when
compared with its compressive strength. It is therefore susceptible to cracking. The cracking process
in concrete is complex because the crack itself is a partially damaged zone with some capability for
stress-transfer in the fracture process zone (FPZ). The FPZ acts as a transition zone between the
discontinuous open crack and the continuous intact material beyond the crack. Although there is
some debate about what constitutes a FPZ, and the size of the FPZ, there is a general agreement that
it exists in concrete [1]. A realistic description of the FPZ is essential in order to understand damage
mechanism and to predict and optimize the behavior of concrete structures.
In reinforced concrete, the fracture process is further complicated by the presence of the
reinforcement that affects the crack development and propagation. The cracking process is
associated with diverse phenomena such as the formation of cracks, crack propagation, the existence
of micro-cracks, interactions between the reinforcement and concrete, and the concrete
microstructure e.g. cement and aggregate [2]. In addition, numerous factors can influence the
cracking process and reinforcement crack bridging including the concrete compressive strength the
type, the properties and the ratio of the longitudinal reinforcement, the bond between the
reinforcement and the concrete, and the geometrical properties and the size of the beam. These
factors can be inter-related and inter-dependent. Furthermore, the cracking process in reinforced
concrete (RC) may involve several macro-cracks propagating at the same time leading to different
failure modes. Internal reinforcement bridges a crack and improves the fracture toughness by
providing a stitching action that prevents the crack faces from opening and controls the crack growth
by increasing the energy demand for crack advancement [3]. The fracture energy is closely related to
the FPZ size and this implies that the existence of a FPZ may be the intrinsic cause for size effects.
In concrete the FPZ covers a narrow crack band and only the region along the crack path is affected
by cracking [4]. However, in reinforced concrete the nature of the FPZ remains unclear. Most
theoretical studies incorporate the reinforcement according to the principle of superposition by
7. 7
considering concrete fracture and adding the effect of the reinforcement as a closing force [5].
Although the fracture properties of reinforced concrete at the structural scale have been studied,
there is a need for further detailed investigations to better understand the nature of the fracture
process Understanding cracking in reinforced concrete is important for the strength assessment and
renovation of existing structures. Relatively few fracture-oriented experimental studies have been
conducted on concrete with internal steel reinforcement. Knowledge of concrete fracture processes
can help identify suitable analytical approaches that capture the details of the crack process. This
study presents an experimental investigation of RC beams subjected to three point bending. A
particular focus is the localized zone around the crack and the crack branching phenomena. Crack
branching is a toughening mechanism in quasi-brittle materials and can be a source of size effects.
Yet it has received little or no attention when studying the fracture of RC beams. In reinforced
concrete, the confinement provided by the reinforcement to the crack path increases the possibility
of crack branching. The crack branching that takes places during the failure process makes the
failure behavior more ductile. The aim of this project is to experimentally determine the relationship
between size, reinforcement ratio and ductility through investigation of crack branching in RC
beams. Although more experiments are required to generalize the results, this project acts as a
foundation to describe the flexural behavior of lightly reinforced concrete beams and for further
investigations of RC fracture processes.
1.2 BACKGROUND AND SCOPE
Over the past decades various studies were conducted to investigate concrete cracking and models
were developed to simulate the cracking process in reinforced concrete beams. These models can
broadly be classified as either plasticity-based models which are justified in the case of ductile
behavior e.g. beams with sufficient internal steel, or fracture mechanics-based models which do not
treat fracture as a point phenomenon but use fracture mechanics principles to explain crack
propagation. The cracking process in concrete is complicated because it is associated with the
development of minor cracks and micro cracks as well as macro-cracks Cracking is also connected
with other phenomena such as strain localization and bridging. In a traditional strength criterion
analysis, the behavior is described using continuum variables of stress and strain. However, during
fracture propagation the behavior depends on what is happening in the fracture process zone (FPZ)
ahead of the crack tip, which is a partially damaged zone with some residual ability to transfer
stress.
8. 8
1.3. OBJECTIVES
This project aims to carry out an in-depth investigation of the crack propagation RCC beams. This will be
achieved through experimental work which is required to observe the true cracking behavior in RC beams.
More specifically, the objectives of this project are:
To study the effect of reinforcement on the crack propagation in concrete beams
To observe the effect of beam depths on relative depth of crack branching.
To study the effect of both beam depth and reinforcement on the ductility of RCC beams through
investigation of crack branching.
To see the relation between the relative depth of crack branching and ductility.
9. 9
Chapter 2
LITERATURE REVIEW
Skarzynski and Tejehman [9] tested small RC beams with a height of 80 mm and length 320 mm
(effective length 240 mm) with a reinforcement ratio of 1.5%. It was found that the localized zones
are always created prior to the attainment of the peak load and the lengths of the fracture zones in
RC beams (0.8 of the beam height) are higher than those in unreinforced concrete beams (0.6 of the
beam height).
Alam et al. [10] used Acoustic Emission (AE) to study microcracking in RC beams. It was found
that as the beam size increases, the fracture process changes from tensile-microcracking
macrocracking to shear-compression macrocracking. Digital image correlation has also been used to
study the cracking in reinforced concrete beams failing in shear and it was found that the observed
size effect was in agreement with Bazant's size effect [I. Annette Beedholm, Jakob Fiskera, Lars
German |12] proposed an approach for predicting crack systems, and more importantly crack
widths in beams from the experimental observations of the crack pattern in flexural members
investigated by Sherwood. The approach assumes the initial existence of flexural cracks the spacing
between which is estimated by a simple empirical relation proposed by Reinbeck. For a certain
configuration of the depth, cover, reinforcement ratio etc. secondary cracks are allowed to develop
in between the flexural cracks. The theoretical results show that the spacing between the flexural
cracks shows a linear proportionality to the effective depth of the member with only a minor
variation with respect to the reinforcement ratio, neglect able for beams with an effective depth
smaller than about 800mm. This is supported by the experimental observations. On the contrary, the
secondary cracks indicate no apparent dependency of the variation in effective depth. When
comparing the results of the estimated crack widths to the measurements that approach it is seen to
precisely reproduce the observed size effect in terms of the relative increase. With respect to the
absolute values of the estimated crack widths a fairly good agreement is also seen.
10. 10
N.A.B. Yehia [13] has done experimental testing of 9 notched reinforced concrete specimens under
four point bending. The beams comprise three beam sizes and three tension reinforcing steel ratios.
All beams have constant span/depth ratio of 4, initial notch/depth ratio of 03. Two strengthening
fiber laminates were used: Glass fiber for the two lower tension reinforcing steel ratios and Carbon
fiber for the higher tension reinforcing steel ratio. The strengthening laminates were designed to
enhance beam moment capacity by 15% to 150% depending on the beam size and reinforcement
ratio. To simulate real life strengthening situations, beams were first loaded until the notch
propagated to 0.5 the beam depth. The strengthening fiber laminate was then introduced to the
tension side of the beam while the load was kept applied to the other side of the beam. The fracture
moment for a given crack depth was calculated through an analytical algorithm which employs
Linear Elastic Fracture Mechanics. The approach takes into consideration the previous loading
history of the beam prior to introducing the strengthening laminate. Test measurements of crack
extension and applied load were used to compare the fracture moment recorded experimentally to
that one calculated analytically. The application of the solution algorithm to different specimen
sizes cross-section dimensions, reinforcement ratio, and strengthening fiber laminate showed that
the solution algorithm is able to effectively predict the behavior of larger beam size and/or
reinforcement better than that of smaller beam size and/or reinforcement. A sensitivity analysis was
conducted to explore this point.
C. Barris et al. [14] have studied the cracking behavior of GFRP RC elements based on the results
of an experimental program involving 15 beams. The paper studies the influence of the reinforcing
material, concrete cover, stirrup spacing and bond between the concrete and the reinforcement. For
this purpose, two different types of GFRP and steel bars were used. The cracking behaviour (erack
width and spacing) in the pure bending zone was analysed up to the service load. Crack width was
consistently acquired by using a Digital Image Correlation (DIC technique. The 2D full-field
displacements of the pure flexural zone were registered using 4 digital cameras and commercial
software that enables the evolution of the specimen cracks to be analysed. Finally, bond coefficients
have been adjusted to different formulations in terms of crack spacing and crack width.
11. 11
2. METHODOLOGY IN DETAIL
LITERATURE REVIEW
Comprehensive study of various parameters was done after the selection of topic. Previous studies,
codal provisions, recent advancement and future scope were considered before the project work
(practical work) was to be commenced.
COLLECTION OF MATERIAL
This step involved procurement of the materials required for construction of beam samples viz.
Cement
Fine aggregates
Coarse aggregates
Steel bars
Formwork board
The instruments for testing of samples involved:
Dial gauges
Crack detection microscope
High resolution digital camera
Loading setup
TESTING OF MATERIALS
The materials were tested in order to authenticate the quality of material to be used for casting the
tests involve physical tests for cement, fine aggregates and coarse aggregates.
FABRICATION OF BEAMS
A total of six unreinforced and reinforced concrete beams of two dimensions were cast under
similar environmental conditions Out of six beams, the two unreinforced beams were set as
12. 12
reference beams to obtain an exact benchmark for comparison. The specifications of the beams and
the percentage of steel reinforcement in each sample are as under:
Sample 1: Reference (control) beam of dimensions 100 mm x 150 mm x 1000 mm
Sample 2: Reference beam of dimensions 100 mm x 200mm x 1200mm
Sample 3: Reinforced beam of same dimensions as that of sample 1 with reinforcement
of 0.3%
. Sample 4: Reinforced beam of same dimensions as that of sample I with reinforcement
of 0.6%
Sample S: Reinforced beam of same dimensions as that of sample 2 with reinforcement
of 0.25%
Sample 6: Reinforced beam of same dimensions as that of sample 2 with reinforcement
of 0.5%
.TESTING OF BEAMS
Each beam was tested to failure under three-point loading. The beams were made to rest on
bearing pads of width 10 cm at the ends which in turn were rested on supports. This was done to
simulate the simply supported conditions as closely as possible.
TEST RESULTS AND DISCUSSION
This includes the analysis to observe the effect of depth and reinforcement on crack propagation
in concrete, strength and ductility.
INTERPRETATION OF RESULTS
Effect of reinforcement on crack propagation is reflected through branching of cracks at different
Percentage of reinforcement. Crack branching is a cause for increase in ductility of beams.
CONCLUSION
This involves brief overview of the data analysis and interpretations. This chapter rounds up the
Whole project and also contains the highlights of the project.
13. 13
Chapter 4
EXPERIMENTAL INVESTIGATION
1. MATERIAL PROPERTIES
Testing of materials was done in order to authenticate the quality of material to be used for casting.
Testing of materials involve physical tests for cement, fine aggregates, and coarse aggregates.
1. CEMENT
The cement used was ordinary Portland cement of grade 43. To determine the properties of cement
several tests were conducted which are as follows.
STANDARD CONSISTENCY
Standard consistency of a cement paste is defined as the water content at which the paste will
permit a Vicar’s plunger having 10 mm dia and 50 mm length to penetrate to a depth of 33-35 mm
from the top of the mould. The test is useful for finding out initial setting time, final setting time,
etc. The standard consistency was found to be 30 %.
Table 4. I: Readings for standard consistency test
Trial No. Water-cement ratio Penetration of plunger (mm)
1 0.25 16
2 0.27 27
3 0.29 32
4 0.295 33.4
5 0.30 34
14. 14
INITIAL SETTING TIME OF CEMENT
Initial setting time of cement is regarded as the time elapsed between the moment when water is
added to the cement to the time when the paste starts losing its plasticity. Using vicat's apparatus, it
is measured as the period elapsed between the moment when water is added to the cement and the
time when the needle (I mm dia) penetrates the test mould to a depth of 33-35 mm from the top at
water content of 0.85 times the standard consistency. The observations obtained are as under
Weight of water 400 g Weight of water-0.85 *30/100*400 102g Initial setting time is obtained as 3
hours 10 minutes.
FINAL SETTING TIME OF CEMENT
The final setting time is the time elapsed between the moment the water is added to the cement and
the time when the paste has completely lost its plasticity and has attained sufficient firmness to
resist certain definite pressure. In vicat’s apparatus, it is the time elapsed between the moment when
water is added to the cement and the time when the center needle makes an impression not more
than 0.5 mm deep while the circular cutting edge of the attachment fails to do so. The final setting
time was observed as 5 hours 40 minutes.
4.1.2 GRADATION OF FINE AGGREGATES
Weight of sample taken 1500 g
Sieves required
4.75 mm
2.36 mm
1.18 mm
600H
-300u and 150
15. Table 4.2 Sieve analysis of sand
Sieve
size
Weight retained
(g)
% wt.
Retained
Cumulative
% wt.
retained
%
finer Remarks
4.75 mm 3 0.2 0.2 99.8
Sand
falls in
zone ΙΙ
2.36 mm 11 0.733 0.933 99.06
1.18 mm 80.5 5.36 6.293 93.70
600µ 747.5 49.8 56.09 43.91
300µ 598 39.86 95.95 4.05
150µ 50.5 3.36 99.31 0.69
As the percentage passing through 600 µ sieve is between 35 and 59, the sand tested belongs to
gradation zone ΙΙ.
-20
Cumulative %age Passing vs. Particle size.
Fig.4.1 gradation curve of sand obtained by sieve analysis
From the gradation curve we find D10 = 0.33, D30 = 0.48, D60 = 0.72
Cu = D60/D10 = 0.72/0.33 = 2.18
Cc = D30
2/(D10 x D60 ) = 0.482/(0.33 x 0.72) =2.02
Thus the sand is poorly graded sand.
20
0
120
100
80
60
40
0 1 2 3 4 5
Gradation curve
15
16. 16
COARSE AGGREGATES
The coarse aggregates used were crushed stone aggregates. The coarse aggregates of two grades
were used one retained on 10 mm sieve and another grade contained aggregates retained on 20 mm
size sieve. The maximum size of coarse aggregate was 20 mm having specific gravity of 2.88
grading confirming to IS: 383-1970.
Table 4. 3: Sieve Analysis of Coarse Aggregate
Description
of sample
Specific
gravity
Grading Remarks
% passing
Coarse
aggregates
20 mm :10
mm::60:40%
2.88
Sieve
designation
(mm)
Conforms to 20
mm full graded
coarse
aggregates as
per IS:383-
Obtained Required
by weight
1970
specifications40 100 100
20 95 100-95
10 32 25-55
4.75 0 0-10
4.1.3 CONCRETE MIX
The concrete mix used was M30 which was designed as per IS 10262-2010. The proportion of
ingredients of concrete required for the design mix was calculated as:
17. 17
Table 4. 4: Concrete mix (M 30)
material Mass required per m3
(kg)
Cement 330
Water 210
Sand 780
Aggregate 1025
TESTING OF CONCRETE CUBES
Three concrete cubes were cast simultaneously with the beam samples using design mix M30 in
order to verify the quality of material and mixing apparatus. The cubes were properly cured and
testing was done after 28 days. The following results were obtained
Table 4.5: Cube strength under compression test
Sample no. Compressive strength (N/mm2)
1 32.4
2 35.6
3 31.8
18. Fig,4.2: Cube failure under compression test
4.1.4 REINFORCEMENT STEEL
The reinforcement steel used in concrete beams was High-Yield Strength Deformed (HYSD) bars
confirming to IS 1786:1985. The yield strength of steel reinforcements used in the experimental
program was determined by performing the standard tensile test on the three specimens of each bar.
The proof stress or yield strength of the specimens are averaged and shown in Table 4.6. The
modulus of elasticity of steel bars was 2 x 105 MPa. The reinforcement involved only steel bars of
f6mm and 8mm diameter which were bended later at the two ends at right angles up to 10 cm
length. The steel bars were used as a flexural reinforcement only.
18
19. Table 4.6: Tensile strength of reinforcing steel bars
Sample Dia of bars (mm) 0.2% proof stress
(N/mm2)
Average proof stress
(N/mm2)
1 8 520
523
2 8 527
3 8 521
4 6 531
5285 6 525
6 6 528
(a) (b)
Fig. 4.3: (a) Steel test specimen tested in UTM (b) Steel test specimen after failure
19
20. 4.1.5 DETAILING OF REINFORCEMENT IN BEAMS
The steel reinforcent bars used in concrete beams were bended at right angles at the ends, these bars
were used as flexural reinforcement only and shear reinforcement was not provided. The steel
reinforcement included the HYSD steel bars of diameters 6mm and 8 mm.
Fig. 4.4: Reinforcement steel used in beams
20
21. 4.1.6 FORMWORK FOR BEAMS
The plywood sheets were sawn in the carpentry shop to form the sheets of required sizes. These
small sheets were joined to form the moulds for beams.
Fig.4.5: Moulds for beams
Fig.4.6: Insulation foam at center for notch provision
21
22. 4.1.6 CASTING OF BEAMS
To cast the beams, the mould for each specimen was held in position with help of side supports. At
the centre of each mould, insulation foam of thickness 6 mm and depths of 20 mm and 25 mm was
provided in beams of depth 150 mm and 200 mm respectively, to serve the function of notch. The
notch was provided to ensure that the flexural cracks occur in beams starting from the notch. After
this, the concrete was made in a mixer and placed in the moulds. In case of reinforced samples clear
cover of 20 mm was provided and to ensure this cover, a layer of plain concrete of thickness 20 mm
in case of beam depth of 150 mm and 25 mm in case of beam depth of 200 mm was laid initially on
which the steel bars were rested to act as flexural reinforcement. As no shear links were used, the
flexural steel bars were held fixed until the concreting was completed flush with the top surface.
The compaction of concrete was done by using needle vibrator.
Fig. 4.7: Casting of beams
22
23. 23
Table 4. 7: Details of test specimens
Concrete cube
comp. strength
(Mpa)
Beams dimension B
X D X L (mm)
Reinforcement ratio Notation
M 30
100 x 150 x 1000
Unreinforced (0%) M30,D150,0%
2T6 (0.3%) M30,D150,0.3%
2T8 (0.6%) M30,D150,0.6%
100 x 200 x 1200
Unreinforced (0%) M30,D200,0%
2T6 (0.25%) M30,D200,0.25%
2 T8 (0.5%) M30,D200,0.5%
A crack inducer was located at mid-span. Insulation foam was used to form the crack inducer where
the foam was cut into pieces with a width of 6 mm and depth of 20 mm for the beams of
dimensions 100*150* 1000 mm and width of 6mm and depth 25 mm for beams of length 100*200
1200 mm. The foam was inserted vertically at the middle of the formwork prior to casting. As no
shear reinforcement is provided, the notch has been provided to ensure that flexural cracks occur
starting from the notch.
24. 24
Remaining course of action
As the casting of beams ended, the beams will be tested under three point loading system and the
Flexure behavior, Ductility factor, Crack propagation and branching of lightly reinforced concrete
beams of different dimensions and varying percentage of reinforcement with respect to unreinforced
concrete reference beams of similar dimensions will be studied.
The impact of varying size of beam on the pattern and propagation of flexure crack will be
studied and the contribution of reinforcement on reduction of these flexure cracks will be of prime
motive and if exists, a relationship will be framed between the percentage of reinforcement and
crack reduction.
25. 25
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