Acute lung infection induced by Extended Spectrum β-Lactamases (ESBL) producing isolates was dete... more Acute lung infection induced by Extended Spectrum β-Lactamases (ESBL) producing isolates was determined by measuring inflammatory mediators; malondialdehyde (MDA), myeloperoxidase (MPO) and nitric oxide (NO). The mice were randomly divided into three groups of 20 animals each. All mice were given 10 4 c.f.u. ml-1 of the test organism intranasally in a volume of 50 µl while holding the mouse in an upright position without any anaesthesia. Group A received an intraperitoneal injection of an antibiotic, imipenem at a dose of 20 mg ml-1 / 25 g body weight which was administered 48 h post infection, Group B received only normal saline orally while group C, control-mice did not receive any treatment. The animals were sacrificed by cervical dislocation; lungs were removed aseptically and examined for various inflammatory mediators. The MDA, NO and MPO estimations in the lung homogenates in each group was measured and compared. Group treated with imipenem recorded lower absorbance values when compared with group treated with normal saline. The different parameters were statistically significant since the P-values were less than 0.05.
Rubberized concrete is made up of scrap tyre rubbers where the fine aggregate is partially replac... more Rubberized concrete is made up of scrap tyre rubbers where the fine aggregate is partially replaced by it, as the waste rubber is being a threat to the environment. It is estimated that only 4% of the waste tyre is used in the application of civil engineering and also there is shortage of fine aggregates. The primary objective of this study is to investigate the preliminary concrete properties of M25 and M30 concretes. The fine aggregate is replaced by pre-treated crumb rubber with 10, 15 and 20 % of total weight. Various tests are conducted on the rubberized concrete specimens such as compressive strength, split tensile strength, flexural strength and slump test. The investigation is carried out to determine the impact load behavior of hybrid rubberized composite slabs. In addition 0%, 1%, 1.5%, and 2% of replacement of rubber fibers for total weight of coarse aggregate is also made. The specimen of size 300 mm x 300 mm x 50 mm thickness is subjected to drop hammer test to find its...
IOSR Journal of Mechanical and Civil Engineering, 2012
This paper presents the results of comparative study conducted to evaluate the strength propertie... more This paper presents the results of comparative study conducted to evaluate the strength properties of high volume flyash concrete(HVFAC) using a cement replacement level of 50%, 55% and 60% in M 20 and M 25 grades of concrete. In this investigation an attempt has been made to study the strength properties of HVFAC specimens in comparison with control OPC concrete specimens of same grade. It is observed that the compressive strength of HVFAC is improved by about 50% cement replacement by fly ash with 1.5% of plasticizer was equal to control concrete.
This paper presents the experimental study of six Double Skinned Hollow Concrete Filled steel Tub... more This paper presents the experimental study of six Double Skinned Hollow Concrete Filled steel Tubular (DSHCFT) columns consisting of PVC inner and mild Steel outer pipes in-filled with Self Compacting Concrete (SCC). The grade of SCC and the yield strength of steel used were M35 and 250 MPa respectively. The Columns were tested for axial load and Loaddeflection, Ultimate compressive strength were studied and reported. The experimental results are verified with European Code (EC4) and found as conservative. The PVC tube is found as a reasonably suitable alternate material for moderately loaded DSHCFT columns.
In this paper, tests on flexural buckling (Lateral-Torsional) of cold-formed steel(CFS) lipped Ch... more In this paper, tests on flexural buckling (Lateral-Torsional) of cold-formed steel(CFS) lipped Channel beams under restrained boundary conditions are described Two point loading for flexural tests have been established for 3.0m span to obtain uniform bending moment. The section sizes selected for testing are 100x50x10 mm, 100x50x15 mm and 100x50x20 mm with 1.6mm and 2.0mm thickness for the investigation. Carefully designed loading and support systems were used in the tests to apply gravity load through the web of the section and to ensure that simply supported ends were established. The test results are compared in the BS5950:Part 5 and IS code 801-1975. The influence of warping and torsional restraints on flexural capacity is presented. The influence of buckling length for different boundary conditions proposed by Rhodes was considered to calculate critical flexural-torsional buckling moment.
This paper presents the details of the flexural behaviour of self-compacting concrete (SCC) ferro... more This paper presents the details of the flexural behaviour of self-compacting concrete (SCC) ferrocement fiber reinforced slab panels. A total of 24 slabs have been tested under flexural loading. The size of the slab is 700 mm (length) x 300 mm (width) x 25 mm and 30 mm (thickness). The parameters studied in this investigation include the fiber content, number of weld mesh layers thickness of ferrocement slabs. Test procedures for self compacting (SCC) have been explained in brief and all the tests have been performed as per EFNARC. From the studies, it is observed that the load carrying capacities, energy absorption, deformation at ultimate load are high in the case of SCC ferrocement hybrid polypropylene fibers. Further, it is observed that there is reduction in crack width and increase in number of cracks in the case of SCC ferrocement hybrid polypropylene fibers indicates delay in crack growth.
In reinforced concrete design an important consideration that can be added to the requirements of... more In reinforced concrete design an important consideration that can be added to the requirements of strength and serviceability is ductility. This consideration is of importance to determine the amount of redistribution of moment that is possible in limited state design. Also, it is of importance in seismic design because to survive a severe earthquake, a structure should be capable of absorbing and dissipating energy by post-elastic deformations. To have an idea about the energy dissipation and ductility, it is essential to conduct impact test. An attempt is made in this paper to cast and test the cylindrical specimens made of Plain Cement Concrete (PCC) and Waste Tyre Rubber Aggregate Concrete (WTRAC) for impact loads with a steel ball drop weight. The test results show that the WTRAC with 6% replacement of both fine and coarse aggregate with rubber aggregates considerably improves the impact resistance and ductility characteristics. Regression model has been developed to estimate t...
In recent years waste handling and management is the primary issue faced by countries all over th... more In recent years waste handling and management is the primary issue faced by countries all over the world. It is very challenging and hectic problem that has to be tackled in an indigenous manner. On the basis of statistical data provided by the Environmental Protection Agency (EPA) 270,000,000 millions waste tyres are produced each year. The disposal of the waste tyres in landfills is a major issue handled by the local municipalities and government sectors. The statistical study gives an estimate that within the next decade the majority of the landfills used for the waste tyre disposal shall be closed and this poses the problem of need for lands for waste dumping. This new problem gave an idea of recycling of waste tyres instead of filling them in bare lands. Recycling of waste is a process adopted by any industry for efficient resource management. The discharge of waste tyres into expensive and the continuously decreasing numbers of landfills generates significant pressure to the l...
Cement concrete is the most widely used construction material in many infrastructure projects. Th... more Cement concrete is the most widely used construction material in many infrastructure projects. The development and use of mineral admixture for cement replacement is growing in construction industry mainly due to the consideration of cost saving, energy saving, environmental production and conservation of resources. Present study is aimed at replacing cement in concrete with activated fly ash. The paper highlights the chemical activation of low calcium fly ash using CaO and Na2SiO3 in the ratio 1:8 for improving the pozzolanic properties of fly ash .The investigation deals with the flexural behavior of beams using chemically activated fly ash at various cement replacement levels of 10%, 20%, 30%, 40%, 50%, and 60% with water binder ratio 0.45.The results are compared with OPC and Activated Fly ash at the same replacement levels.
The most important challenges in the construction field is to do the experimentation of the desig... more The most important challenges in the construction field is to do the experimentation of the designing at real time. It leads to the wastage of the materials and time consuming process. In this paper, an artificial neural network based model for the verification of sigma section characteristics like shear centre and deflection are designed and verified. The physical properties like weight, depth, flange, lip, outer web, thickness, and area to bring shear centre are used in the model. Similarly, weight, purlin centres with allowable loading of different values used in the model for deflection verification. The overall average error rate as 1.278 percent to the shear centre and 2.967 percent to the deflection are achieved by the model successfully. The proposed model will act as supportive tool to the steel roof constructors, engineers, and designers who are involved in construction as well as in the section fabricators industry.
International Journal of Environment and Sustainable Development
The aim of this study is to investigate the effect of adding fly ash, an industrial by-product an... more The aim of this study is to investigate the effect of adding fly ash, an industrial by-product and coconut shell, an agricultural waste on the mechanical and flexural characteristics of eco-concrete. The study focuses on density, compressive strength, tensile strength and flexural behaviour of the coconut shell eco-concrete. Two different mixes are developed, one with coconut shell and the other with conventional aggregate and coconut shell as coarse aggregate. The cement content is replaced with class F fly ash at 0%, 10%, 20% and 30% by weight. The test result shows that the coconut shell concrete produced with 10% fly ash has recorded higher compressive, tensile strength than other proportions. Fly ash inclusion further reduces the density of coconut shell concrete. The higher deflection of coconut shell concrete before failure shows that it has failed in a ductile manner. The flexural behaviour is comparable with other lightweight concretes. It is suggested that an eco-friendly, cost effective structural lightweight concrete can be produced by using coconut shell and fly ash.
IRA-International Journal of Technology & Engineering (ISSN 2455-4480), 2016
The aim of this paper is to examine the flexural behaviour of structural beams made of high volum... more The aim of this paper is to examine the flexural behaviour of structural beams made of high volume fly ash (HVFA) concrete with confined stirrups introduced in compression regions.Generally concrete is low tensile strength and poor ductile property. By confining compression regions introduced with closed stirrups which improves the ductility and load carrying capacity of beams. The introduction of stirrups to these regions would suppress the development of tensile stresses.Fly ash (FA) has been used in concrete and identified such a product as Eco smart or green concrete. In earth quake regions it becomes essential to construct the structures as a ductile one. Sudden failures due to poor workability of RC structures can be avoided, if critical sections are able to undergo large plastic deformations and to absorb large amount of strain energy.The results indicated that the confinement in the form of stirrups improves the ultimate strength and ductile behaviour of the concrete. It has...
In this paper, totally 7 innovative steel concrete composite columns were investigated for axial ... more In this paper, totally 7 innovative steel concrete composite columns were investigated for axial load and reported. 6 of them were modified DSHCFT columns consisting only outer skin tube and butting concrete and the remaining one was Double Skinned Hollow Concrete Filled steel Tubular columns having outer and inner steel tube (DSHCFT), which was annularly in-filled with Self-Compacting Concrete (SCC). The concrete grade and yield strength of steel tubes used were respectively M35 and 250MPa. The ratios of outer tube diameter to its thickness were 34 to 36. The length to outer diameter (aspect ratio) and the hollowness ratio were from 2.4 to 4.5 and from 0.35 to 0.5 respectively. Mechanical behaviour in term of stiffness, confinement, ultimate strength and ductility were discussed. Load Vs mid-span deflection diagrams, failure patterns of the specimens are presented. The existence of composite action between steel and concrete and confinement of concrete were experimentally evidenced...
The project area and it surrounding region has been a drought prone area since quite a long time.... more The project area and it surrounding region has been a drought prone area since quite a long time. The majority of the population in this region lives in villages where agriculture is the main source of income. In order to utilize the river water to the possible extent and distributing the same among all the areas of the state, these projects were proposed. This Lift Irrigation Scheme was proposed in to irrigate an ayacut of 1.23 lakh acres and to supply drinking water to the enroute villages [6].
A series of experiments on composite beams reinforced with Prefabricated Cage System is reported.... more A series of experiments on composite beams reinforced with Prefabricated Cage System is reported. The experiments include eleven series of composite beams. The tests reported were used to ascertain the flexural strength of the beams and to validate the theoretical predictions. Companion specimens of concrete cylinders and cubes were tested for compressive strength and elastic modulus properties. Specimens of cold formed steel sheeting coupons were tested in tension to ascertain their yield strength and young's modulus. Failure shown is occur in pure bending region. In this study, the effects of concrete strength and confinement on flexural ductility of PCRC beams have been evaluated in terms of a parameter known as the ductility factor and this gives an indication of the ability of a structural member to deform. The results reveal that PCRC beams show better ductile performance and maintain their loading upto the loading. There was good agreement between the results obtained fro...
Acute lung infection induced by Extended Spectrum β-Lactamases (ESBL) producing isolates was dete... more Acute lung infection induced by Extended Spectrum β-Lactamases (ESBL) producing isolates was determined by measuring inflammatory mediators; malondialdehyde (MDA), myeloperoxidase (MPO) and nitric oxide (NO). The mice were randomly divided into three groups of 20 animals each. All mice were given 10 4 c.f.u. ml-1 of the test organism intranasally in a volume of 50 µl while holding the mouse in an upright position without any anaesthesia. Group A received an intraperitoneal injection of an antibiotic, imipenem at a dose of 20 mg ml-1 / 25 g body weight which was administered 48 h post infection, Group B received only normal saline orally while group C, control-mice did not receive any treatment. The animals were sacrificed by cervical dislocation; lungs were removed aseptically and examined for various inflammatory mediators. The MDA, NO and MPO estimations in the lung homogenates in each group was measured and compared. Group treated with imipenem recorded lower absorbance values when compared with group treated with normal saline. The different parameters were statistically significant since the P-values were less than 0.05.
Rubberized concrete is made up of scrap tyre rubbers where the fine aggregate is partially replac... more Rubberized concrete is made up of scrap tyre rubbers where the fine aggregate is partially replaced by it, as the waste rubber is being a threat to the environment. It is estimated that only 4% of the waste tyre is used in the application of civil engineering and also there is shortage of fine aggregates. The primary objective of this study is to investigate the preliminary concrete properties of M25 and M30 concretes. The fine aggregate is replaced by pre-treated crumb rubber with 10, 15 and 20 % of total weight. Various tests are conducted on the rubberized concrete specimens such as compressive strength, split tensile strength, flexural strength and slump test. The investigation is carried out to determine the impact load behavior of hybrid rubberized composite slabs. In addition 0%, 1%, 1.5%, and 2% of replacement of rubber fibers for total weight of coarse aggregate is also made. The specimen of size 300 mm x 300 mm x 50 mm thickness is subjected to drop hammer test to find its...
IOSR Journal of Mechanical and Civil Engineering, 2012
This paper presents the results of comparative study conducted to evaluate the strength propertie... more This paper presents the results of comparative study conducted to evaluate the strength properties of high volume flyash concrete(HVFAC) using a cement replacement level of 50%, 55% and 60% in M 20 and M 25 grades of concrete. In this investigation an attempt has been made to study the strength properties of HVFAC specimens in comparison with control OPC concrete specimens of same grade. It is observed that the compressive strength of HVFAC is improved by about 50% cement replacement by fly ash with 1.5% of plasticizer was equal to control concrete.
This paper presents the experimental study of six Double Skinned Hollow Concrete Filled steel Tub... more This paper presents the experimental study of six Double Skinned Hollow Concrete Filled steel Tubular (DSHCFT) columns consisting of PVC inner and mild Steel outer pipes in-filled with Self Compacting Concrete (SCC). The grade of SCC and the yield strength of steel used were M35 and 250 MPa respectively. The Columns were tested for axial load and Loaddeflection, Ultimate compressive strength were studied and reported. The experimental results are verified with European Code (EC4) and found as conservative. The PVC tube is found as a reasonably suitable alternate material for moderately loaded DSHCFT columns.
In this paper, tests on flexural buckling (Lateral-Torsional) of cold-formed steel(CFS) lipped Ch... more In this paper, tests on flexural buckling (Lateral-Torsional) of cold-formed steel(CFS) lipped Channel beams under restrained boundary conditions are described Two point loading for flexural tests have been established for 3.0m span to obtain uniform bending moment. The section sizes selected for testing are 100x50x10 mm, 100x50x15 mm and 100x50x20 mm with 1.6mm and 2.0mm thickness for the investigation. Carefully designed loading and support systems were used in the tests to apply gravity load through the web of the section and to ensure that simply supported ends were established. The test results are compared in the BS5950:Part 5 and IS code 801-1975. The influence of warping and torsional restraints on flexural capacity is presented. The influence of buckling length for different boundary conditions proposed by Rhodes was considered to calculate critical flexural-torsional buckling moment.
This paper presents the details of the flexural behaviour of self-compacting concrete (SCC) ferro... more This paper presents the details of the flexural behaviour of self-compacting concrete (SCC) ferrocement fiber reinforced slab panels. A total of 24 slabs have been tested under flexural loading. The size of the slab is 700 mm (length) x 300 mm (width) x 25 mm and 30 mm (thickness). The parameters studied in this investigation include the fiber content, number of weld mesh layers thickness of ferrocement slabs. Test procedures for self compacting (SCC) have been explained in brief and all the tests have been performed as per EFNARC. From the studies, it is observed that the load carrying capacities, energy absorption, deformation at ultimate load are high in the case of SCC ferrocement hybrid polypropylene fibers. Further, it is observed that there is reduction in crack width and increase in number of cracks in the case of SCC ferrocement hybrid polypropylene fibers indicates delay in crack growth.
In reinforced concrete design an important consideration that can be added to the requirements of... more In reinforced concrete design an important consideration that can be added to the requirements of strength and serviceability is ductility. This consideration is of importance to determine the amount of redistribution of moment that is possible in limited state design. Also, it is of importance in seismic design because to survive a severe earthquake, a structure should be capable of absorbing and dissipating energy by post-elastic deformations. To have an idea about the energy dissipation and ductility, it is essential to conduct impact test. An attempt is made in this paper to cast and test the cylindrical specimens made of Plain Cement Concrete (PCC) and Waste Tyre Rubber Aggregate Concrete (WTRAC) for impact loads with a steel ball drop weight. The test results show that the WTRAC with 6% replacement of both fine and coarse aggregate with rubber aggregates considerably improves the impact resistance and ductility characteristics. Regression model has been developed to estimate t...
In recent years waste handling and management is the primary issue faced by countries all over th... more In recent years waste handling and management is the primary issue faced by countries all over the world. It is very challenging and hectic problem that has to be tackled in an indigenous manner. On the basis of statistical data provided by the Environmental Protection Agency (EPA) 270,000,000 millions waste tyres are produced each year. The disposal of the waste tyres in landfills is a major issue handled by the local municipalities and government sectors. The statistical study gives an estimate that within the next decade the majority of the landfills used for the waste tyre disposal shall be closed and this poses the problem of need for lands for waste dumping. This new problem gave an idea of recycling of waste tyres instead of filling them in bare lands. Recycling of waste is a process adopted by any industry for efficient resource management. The discharge of waste tyres into expensive and the continuously decreasing numbers of landfills generates significant pressure to the l...
Cement concrete is the most widely used construction material in many infrastructure projects. Th... more Cement concrete is the most widely used construction material in many infrastructure projects. The development and use of mineral admixture for cement replacement is growing in construction industry mainly due to the consideration of cost saving, energy saving, environmental production and conservation of resources. Present study is aimed at replacing cement in concrete with activated fly ash. The paper highlights the chemical activation of low calcium fly ash using CaO and Na2SiO3 in the ratio 1:8 for improving the pozzolanic properties of fly ash .The investigation deals with the flexural behavior of beams using chemically activated fly ash at various cement replacement levels of 10%, 20%, 30%, 40%, 50%, and 60% with water binder ratio 0.45.The results are compared with OPC and Activated Fly ash at the same replacement levels.
The most important challenges in the construction field is to do the experimentation of the desig... more The most important challenges in the construction field is to do the experimentation of the designing at real time. It leads to the wastage of the materials and time consuming process. In this paper, an artificial neural network based model for the verification of sigma section characteristics like shear centre and deflection are designed and verified. The physical properties like weight, depth, flange, lip, outer web, thickness, and area to bring shear centre are used in the model. Similarly, weight, purlin centres with allowable loading of different values used in the model for deflection verification. The overall average error rate as 1.278 percent to the shear centre and 2.967 percent to the deflection are achieved by the model successfully. The proposed model will act as supportive tool to the steel roof constructors, engineers, and designers who are involved in construction as well as in the section fabricators industry.
International Journal of Environment and Sustainable Development
The aim of this study is to investigate the effect of adding fly ash, an industrial by-product an... more The aim of this study is to investigate the effect of adding fly ash, an industrial by-product and coconut shell, an agricultural waste on the mechanical and flexural characteristics of eco-concrete. The study focuses on density, compressive strength, tensile strength and flexural behaviour of the coconut shell eco-concrete. Two different mixes are developed, one with coconut shell and the other with conventional aggregate and coconut shell as coarse aggregate. The cement content is replaced with class F fly ash at 0%, 10%, 20% and 30% by weight. The test result shows that the coconut shell concrete produced with 10% fly ash has recorded higher compressive, tensile strength than other proportions. Fly ash inclusion further reduces the density of coconut shell concrete. The higher deflection of coconut shell concrete before failure shows that it has failed in a ductile manner. The flexural behaviour is comparable with other lightweight concretes. It is suggested that an eco-friendly, cost effective structural lightweight concrete can be produced by using coconut shell and fly ash.
IRA-International Journal of Technology & Engineering (ISSN 2455-4480), 2016
The aim of this paper is to examine the flexural behaviour of structural beams made of high volum... more The aim of this paper is to examine the flexural behaviour of structural beams made of high volume fly ash (HVFA) concrete with confined stirrups introduced in compression regions.Generally concrete is low tensile strength and poor ductile property. By confining compression regions introduced with closed stirrups which improves the ductility and load carrying capacity of beams. The introduction of stirrups to these regions would suppress the development of tensile stresses.Fly ash (FA) has been used in concrete and identified such a product as Eco smart or green concrete. In earth quake regions it becomes essential to construct the structures as a ductile one. Sudden failures due to poor workability of RC structures can be avoided, if critical sections are able to undergo large plastic deformations and to absorb large amount of strain energy.The results indicated that the confinement in the form of stirrups improves the ultimate strength and ductile behaviour of the concrete. It has...
In this paper, totally 7 innovative steel concrete composite columns were investigated for axial ... more In this paper, totally 7 innovative steel concrete composite columns were investigated for axial load and reported. 6 of them were modified DSHCFT columns consisting only outer skin tube and butting concrete and the remaining one was Double Skinned Hollow Concrete Filled steel Tubular columns having outer and inner steel tube (DSHCFT), which was annularly in-filled with Self-Compacting Concrete (SCC). The concrete grade and yield strength of steel tubes used were respectively M35 and 250MPa. The ratios of outer tube diameter to its thickness were 34 to 36. The length to outer diameter (aspect ratio) and the hollowness ratio were from 2.4 to 4.5 and from 0.35 to 0.5 respectively. Mechanical behaviour in term of stiffness, confinement, ultimate strength and ductility were discussed. Load Vs mid-span deflection diagrams, failure patterns of the specimens are presented. The existence of composite action between steel and concrete and confinement of concrete were experimentally evidenced...
The project area and it surrounding region has been a drought prone area since quite a long time.... more The project area and it surrounding region has been a drought prone area since quite a long time. The majority of the population in this region lives in villages where agriculture is the main source of income. In order to utilize the river water to the possible extent and distributing the same among all the areas of the state, these projects were proposed. This Lift Irrigation Scheme was proposed in to irrigate an ayacut of 1.23 lakh acres and to supply drinking water to the enroute villages [6].
A series of experiments on composite beams reinforced with Prefabricated Cage System is reported.... more A series of experiments on composite beams reinforced with Prefabricated Cage System is reported. The experiments include eleven series of composite beams. The tests reported were used to ascertain the flexural strength of the beams and to validate the theoretical predictions. Companion specimens of concrete cylinders and cubes were tested for compressive strength and elastic modulus properties. Specimens of cold formed steel sheeting coupons were tested in tension to ascertain their yield strength and young's modulus. Failure shown is occur in pure bending region. In this study, the effects of concrete strength and confinement on flexural ductility of PCRC beams have been evaluated in terms of a parameter known as the ductility factor and this gives an indication of the ability of a structural member to deform. The results reveal that PCRC beams show better ductile performance and maintain their loading upto the loading. There was good agreement between the results obtained fro...
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