Sunil Kute - Academia.edu (original) (raw)
Papers by Sunil Kute
Delays in casting of freshly prepared concrete mix is always uncertain and cannot be predicted in... more Delays in casting of freshly prepared concrete mix is always uncertain and cannot be predicted in the initial time. The interval of time t between the preparation of dry mix including the water addition i.e. t = 0 and casting of the same concrete where required at some elapsed time t is called as time lag. In this paper, attempt is made to correlate the experimental splitting tensile strength variation of partially set concrete (PSC) with the analytical model developed earlier for selfing and the correlation factors are estimated. Also as the success of any task is always contingent on the ability to make decisions and recognize to select the best feasible option from a variety of options. Therefore a multi criteria decision making (MCDM) tool is implemented for ascertaining the suitable concrete mix of PSC. Three different types of concrete mix were tried and compared to the normal mix to check the variation in splitting strength. The experimental and analytical values of tensile s...
NEW ARCH-INTERNATIONAL JOURNAL OF CONTEMPORARY ARCHITECTURE, Jun 25, 2021
Due to tremor buildings are damaged partly or totally. Predominantly soft storeys are mostly affe... more Due to tremor buildings are damaged partly or totally. Predominantly soft storeys are mostly affected. In general such structures are repaired and used again. In this regard, an experimental investigation was planned and conducted for bare R.C. (Reinforced concrete) frames up to collapse and then such collapsed frames repaired with epoxy resin were tested to obtain ultimate load and results are compared. All these frames were tested up to collapse and subjected to only horizontal loads to obtain an effective and possible solution for retrofitted frames which can be reused for soft storeys. In comparison to bare R.C. frames, epoxy repaired frames have comparable lateral load capacity. For the similar load epoxy repaired frames have maximum deformation under control in comparision to bare R.C.frames.
International Journal of Civil and Structural Engineering, 2015
Soft computing tools neural network and fuzzy logic can be used for the problems, where no soluti... more Soft computing tools neural network and fuzzy logic can be used for the problems, where no solution algorithm is known. The mix design of concrete can be put under same category of problem. Again, development of required concrete mix, which required large sets of trial, is a very complex problem in itself. The feature of computer aided soft computing tools can be used to obtain perfect relationship between various design parameters of concrete mix (Aggregate/Cement, Water/Cement, Workability, Durability, Strength) and reduces the requirement of large number of trails. A Artificial Neural Network based five layer system has been proposed to design a concrete mix, based on Department of Environmental Engineering (D.O.E.) method. The results obtained from five layers artificial neural network system are evaluated and compared with traditional method of concrete mix design (D.O.E.). The result shows that ANN has strong potential as a feasible tool for estimating the ingredients of concr...
The steel tubular column filled with steel reinforced concrete (SRCFT), is formed by inserting a ... more The steel tubular column filled with steel reinforced concrete (SRCFT), is formed by inserting a steel section into a concrete filled steel tube. In the current paper, a new shape, namely Castellated Cruciform Steel Section (CCSS), for reinforcing of CFT columns has been proposed to improve the compressive strength and hysteresis behavior of these columns under moderate and severe earthquake excitations. A comprehensive study has been conducted to investigate the strength of SRCFT columns reinforced with castellated and traditional cruciform steel sections, made with thin-walled, welded I-section. The paper describes and presents the results of the testing of four small size (155 mm*155 mm) and short column specimens. The experimental results indicate that the new steel section causes high strength and better post yield behavior of SRCFT columns, because of the increase of shear and bending strength, torsion resistance and interaction between the hollow steel section and concrete. I...
This paper outlines the finite element procedure for simulating the performance of a reinforced s... more This paper outlines the finite element procedure for simulating the performance of a reinforced soil segmental (modular blocks) wall. Analyses were performed using a software code which is developed in FORTRAN and validated for reported case histories in the literature. The material properties of the wall like backfill, foundation, modular concrete fascia blocks and reinforcement were expressed using linear elastic models. A series of parametric studies was conducted to identify effects of reinforcement, stiffness and Poison’s ratio of backfill and foundation strata on the performance of the wall. Increased stiffness of backfill and foundation improves the performance of the wall by restraining the front face deformation. The design charts for deflections at top and bottom and also, height of rotation are developed in the current work by varying the stiffness of backfill and foundation. These charts are useful to the designer to choose appropriate backfill and also, to ascertain the...
Infilled walls are normally considered as non-structural elements. However these walls are effect... more Infilled walls are normally considered as non-structural elements. However these walls are effective in carrying lateral loads. In this regard, an experimental investigation was planned and conducted to study the effect of braced Reinforced Concrete (R.C.) frames in contrast to the bare frames. All these frames were tested up to collapse and subjected to only horizontal loads to obtain an efficient and probable solution for soft storey. In comparison to bare R.C. frames, steel braced R.C. frames have an increase by a notable amount for stiffness and ultimate lateral load capacity. Central braced system is additional effectual than that of corner and diagonal braced system. For the similar load braced R.C. frames have considerable less deflection than that of the bare R.C. frames. The contribution of central and diagonal bracing in comparison to corner bracing is observed to be 20% and 50% correspondingly. The percentage increase in stiffness for braced frames in comparison to bare R...
The effect of elevated temperature, its duration and cooling condition on compressive and flexura... more The effect of elevated temperature, its duration and cooling condition on compressive and flexural strength of concrete is a complex phenomenon and its characterization is governed by several other parameters related to concrete. The destructive testing of concrete subjected to elevated temperature for evaluating its compressive and flexural strength consumes time and put constraints on field schedules and hence there is need to develop the mathematical model which can provide an accurate range of results based on previous data. This paper presents the capability and application of dimensional analysis using Buckingham’s 𝜋 theorem approach for predicting compressive and flexural strength of M-20 and M-40 grade concrete subjected to elevated temperature. A mathematical model is developed using Buckingham’s 𝜋 theorem. The functional relationship of variables of concrete is expressed in the form of an exponential equation which is dimensionally homogeneous. A dimensional constant is de...
Due to tremor buildings are damaged partly or totally. Predominantly soft storeys are mostly affe... more Due to tremor buildings are damaged partly or totally. Predominantly soft storeys are mostly affected. In general such structures are repaired and used again. In this regard, an experimental investigation was planned and conducted for bare R.C. (Reinforced concrete) frames up to collapse and then such collapsed frames repaired with epoxy resin were tested to obtain ultimate load and results are compared. All these frames were tested up to collapse and subjected to only horizontal loads to obtain an effective and possible solution for retrofitted frames which can be reused for soft storeys. In comparison to bare R.C. frames, epoxy repaired frames have comparable lateral load capacity. For the similar load epoxy repaired frames have maximum deformation under control in comparision to bare R.C.frames.
Bamboo is a giant grass and not a tree. Bamboo completes its growth within some months and mature... more Bamboo is a giant grass and not a tree. Bamboo completes its growth within some months and matures at the age of around three years, there is no secondary growth. Moisture content of bamboo varies along its height location and with seasoning period, which affects all physical and mechanical properties. It is one of the important factors in deciding the life of bamboo. This paper presents results of experimental investigations made to evaluate the physical and mechanical properties of the bamboo species Dendrocalamus strictus and its utilization potential as building material may be as whole or in the split form. In the present study moisture content, specific gravity, water absorption, dimensional changes, tensile and compressive strength at different height location are worked out. The moisture content varies along the height for green bamboo or at any time after harvesting. The top portions had consistently lower moisture content than the middle or basal at all stages of seasoning...
A large numbers of buildings are constructed with masonry infill for functional or aesthetic reas... more A large numbers of buildings are constructed with masonry infill for functional or aesthetic reasons. S ometimes window or ventilator openings have been left in the wall for architectural necessities. Constructions with such partial masonry infill face serious earthquake shear damages in columns due to captive-column effect. Due to complex behavior of partial infill structures are analyzed and designed as bare frames. The purpose of this research is to investigate the behavior of steel frames by using steel bracing under lateral loading and to reduce the potential for capti ve-column damage. An experimental study is carried out on single, single storey for steel frames with bare, corner, central and horizontal steel bracing.All such frames were tested up to collapse and subjected only to horizontal loads to obtain an effective and possible solution for captive column.In comparison to bare, braced frames have significant increase in lateral load capacity. Central bracing is more effe...
International Journal of Innovative Research in Science, Engineering and Technology, 2014
Number of buildings is constructed with partial masonry infill for serviceable or artistic reason... more Number of buildings is constructed with partial masonry infill for serviceable or artistic reasons. Sometimes openings have been left a window or ventilator in the wall for architectural necessities. Constructions with such partial masonry infill face serious damages because of captive-column effect at the time of earthquake. Due to complex behavior of partial infill, structures are analyzed and designed as bare frames. The purpose of this research is to investigate the behavior of Reinforced Concrete (R.C.) frames by using steel bracing under horizontal loading and to decrease the potential for captive-column damage. An experimental study is carried out on single, single storey for R.C. frames with bare and corner steel bracing. All such frames were tested up to collapse and subjected only to monotonic static lateral load to obtain an effective and possible solution for captive column. In comparison to bare, braced frames have noteworthy increase in lateral load capacity. Central b...
Indian journal of applied research, 2011
Gayatri R. Gadekar Dr. Sunil Kute
International Journal of Engineering and Advanced Technology, 2020
Ferrocement is one of the most inexpensive and alternative construction techniques. The beauty of... more Ferrocement is one of the most inexpensive and alternative construction techniques. The beauty of this materials attracts in analyzing and designing the ferrocement (F.C.) silo. This has encouraged the search for new materials like F.C. to provide an alternative to reinforced concrete. During last two decades, many attempts have been made to develop computational models for analysis of silos particularly in steel and reinforced cement concrete. However, very less work is reported on scientific development of analysis of F.C. silo. This indicates that there is a need to continue with more focus and detailed research on F.C. silo. There is a need to analyze F.C. silo for various parametric findings related to pressure and behavior of silo in tension, compression and flexure. Present paper reports new aspects of analysis of silo. The parametric study of stresses developed in wall of F.C. silo for different H/D ratio, thickness and storage capacity is done with help of commercial ANSYS ...
International Journal of Advanced Structural Engineering, 2018
SRCFT columns are formed by inserting a steel section into a concrete-filled steel tube. These ty... more SRCFT columns are formed by inserting a steel section into a concrete-filled steel tube. These types of columns are named steel-reinforced concrete-filled steel tubular (SRCFT) columns. The current study aims at investigating the various types of reinforcing steel section to improve the strength and hysteresis behavior of SRCFT columns under axial and lateral cyclic loading. To attain this objective, a numerical study has been conducted on a series of composite columns. First, FEM procedure has been verified by the use of available experimental studies. Next, eight composite columns having different types of cross sections were analyzed. For comparison purpose, the base model was a CFT column used as a benchmark specimen. Nevertheless, the other specimens were SRCFT types. The results indicate that reinforcement of a CFT column through this method leads to enhancement in load-carrying capacity, enhancement in lateral drift ratio, ductility, preventing of local buckling in steel shell, and enhancement in energy absorption capacity. Under cyclic displacement history, it was observed that the use of cross-shaped reinforcing steel section causes a higher level of energy dissipation and the moment of inertia of the reinforcing steel sections was found to be the most significant parameter affecting the hysteresis behavior of SRCFT columns.
World Journal of Engineering, 2018
Purpose The main function of the castellation process is making I-sections stiffer by increasing ... more Purpose The main function of the castellation process is making I-sections stiffer by increasing the height of web and supplying a higher moment capacity of primary axis than plain-webbed members of the same weight. In addition, it optimizes the use of heavy, costly constructional steel material and provides good services accessibility. The purpose of this study was to investigate the strength and buckling behavior of axially loaded castellated cruciform steel columns using finite element analysis. Although a significant body of research exists on the failure of different columns, there is no proper criterion introduced to determine the point of buckling in the equilibrium path of an imperfect column. Design/methodology/approach This paper considers a wide range of practical geometric dimensions and various end conditions using ANSYS software. Findings are reported for about 224 samples of castellated cruciform I-shaped sections, and a simplified approach to evaluate buckling capacity of castellated columns, using the slenderness-load curve, is developed. In addition, the axial compressive capacities of those steel sections are investigated numerically in the current study. Findings The results of nonlinear analyses of these columns revealed that the load-carrying capacity of castellated cruciform steel columns far outweighs and is more appropriate than that of the traditional cruciform steel columns. In the present paper, new geometric criteria have been introduced having the ability to cover different types of columns. It shows the critical load of columns in the range of elastic and inelastic behavior. Practical implications This study can provide a background for practical engineering applications and design specifications for steel structures with castellated sections. In the present paper, new geometric criteria have been introduced having the ability to cover different types of columns. It shows the critical load of columns showing both elastic and inelastic behavior. Because this method showed reliable performance, it can be used during experimental tests for detecting buckling point. Originality/value This study can provide background for practical engineering applications and design specifications for steel structures with castellated sections; also, a physical criterion has been defined for calculating the buckling load of real columns.
Engineering Structures, 2018
The additive model of shear strength of reinforced concrete (RC) members, i.e. shear strength (V)... more The additive model of shear strength of reinforced concrete (RC) members, i.e. shear strength (V) is equal to the sum of the contribution from concrete (V c) and that from transverse reinforcement (V s), has been widely accepted in the literature and engineering practice. Shear span-to-depth ratio (a/d) is known to be a significant factor affecting V of RC members. However, very few quantitative studies on the influence of a/d on V c and V s have been reported in the literature. Another issue is related to the controversial relationship between the shear force at first diagonal cracking (V cr) and V c , for which different guidelines are given in ACI, AASHTO LRFD and CSA codes. Through direct measurement of V c and V s from 11 RC beam tests, this work provides experimental evidence for these issues. The experimental results show that V c can be very different from V cr. At small shear span-to-depth ratio (a/d), V c is much larger than V cr , while it is the opposite for beams with a large a/d value. Not all stirrups crossing the critical shear crack yield at ultimate shear strength, and V c as well as V s are not constant under increasing member deformation. Although design codes give a conservative prediction of V, they predict an un-conservative value of V c at large a/d.
Journal of Civil Engineering and Science, 2015
Optimal proportions of concrete mix ingredients are vital for establishing a relationship between... more Optimal proportions of concrete mix ingredients are vital for establishing a relationship between the best particle distribution and the corresponding degree of packing. The maximum strength is attained when the porosity of the granular structure is minimal to the minimum voids ratio. Concrete is a particulate material, and the particle-packing theory has significance when designing a concrete mix. The objective of this work was to produce an optimum concrete mix of required design stipulations based on combinations of optimized aggregate grading and effective estimation of the required water and cement. The present work investigated the potential of the particle-packing phenomenon to optimize the cement and water content and improve concrete properties with an "aggregate to paste" approach.
Delays in casting of freshly prepared concrete mix is always uncertain and cannot be predicted in... more Delays in casting of freshly prepared concrete mix is always uncertain and cannot be predicted in the initial time. The interval of time t between the preparation of dry mix including the water addition i.e. t = 0 and casting of the same concrete where required at some elapsed time t is called as time lag. In this paper, attempt is made to correlate the experimental splitting tensile strength variation of partially set concrete (PSC) with the analytical model developed earlier for selfing and the correlation factors are estimated. Also as the success of any task is always contingent on the ability to make decisions and recognize to select the best feasible option from a variety of options. Therefore a multi criteria decision making (MCDM) tool is implemented for ascertaining the suitable concrete mix of PSC. Three different types of concrete mix were tried and compared to the normal mix to check the variation in splitting strength. The experimental and analytical values of tensile s...
NEW ARCH-INTERNATIONAL JOURNAL OF CONTEMPORARY ARCHITECTURE, Jun 25, 2021
Due to tremor buildings are damaged partly or totally. Predominantly soft storeys are mostly affe... more Due to tremor buildings are damaged partly or totally. Predominantly soft storeys are mostly affected. In general such structures are repaired and used again. In this regard, an experimental investigation was planned and conducted for bare R.C. (Reinforced concrete) frames up to collapse and then such collapsed frames repaired with epoxy resin were tested to obtain ultimate load and results are compared. All these frames were tested up to collapse and subjected to only horizontal loads to obtain an effective and possible solution for retrofitted frames which can be reused for soft storeys. In comparison to bare R.C. frames, epoxy repaired frames have comparable lateral load capacity. For the similar load epoxy repaired frames have maximum deformation under control in comparision to bare R.C.frames.
International Journal of Civil and Structural Engineering, 2015
Soft computing tools neural network and fuzzy logic can be used for the problems, where no soluti... more Soft computing tools neural network and fuzzy logic can be used for the problems, where no solution algorithm is known. The mix design of concrete can be put under same category of problem. Again, development of required concrete mix, which required large sets of trial, is a very complex problem in itself. The feature of computer aided soft computing tools can be used to obtain perfect relationship between various design parameters of concrete mix (Aggregate/Cement, Water/Cement, Workability, Durability, Strength) and reduces the requirement of large number of trails. A Artificial Neural Network based five layer system has been proposed to design a concrete mix, based on Department of Environmental Engineering (D.O.E.) method. The results obtained from five layers artificial neural network system are evaluated and compared with traditional method of concrete mix design (D.O.E.). The result shows that ANN has strong potential as a feasible tool for estimating the ingredients of concr...
The steel tubular column filled with steel reinforced concrete (SRCFT), is formed by inserting a ... more The steel tubular column filled with steel reinforced concrete (SRCFT), is formed by inserting a steel section into a concrete filled steel tube. In the current paper, a new shape, namely Castellated Cruciform Steel Section (CCSS), for reinforcing of CFT columns has been proposed to improve the compressive strength and hysteresis behavior of these columns under moderate and severe earthquake excitations. A comprehensive study has been conducted to investigate the strength of SRCFT columns reinforced with castellated and traditional cruciform steel sections, made with thin-walled, welded I-section. The paper describes and presents the results of the testing of four small size (155 mm*155 mm) and short column specimens. The experimental results indicate that the new steel section causes high strength and better post yield behavior of SRCFT columns, because of the increase of shear and bending strength, torsion resistance and interaction between the hollow steel section and concrete. I...
This paper outlines the finite element procedure for simulating the performance of a reinforced s... more This paper outlines the finite element procedure for simulating the performance of a reinforced soil segmental (modular blocks) wall. Analyses were performed using a software code which is developed in FORTRAN and validated for reported case histories in the literature. The material properties of the wall like backfill, foundation, modular concrete fascia blocks and reinforcement were expressed using linear elastic models. A series of parametric studies was conducted to identify effects of reinforcement, stiffness and Poison’s ratio of backfill and foundation strata on the performance of the wall. Increased stiffness of backfill and foundation improves the performance of the wall by restraining the front face deformation. The design charts for deflections at top and bottom and also, height of rotation are developed in the current work by varying the stiffness of backfill and foundation. These charts are useful to the designer to choose appropriate backfill and also, to ascertain the...
Infilled walls are normally considered as non-structural elements. However these walls are effect... more Infilled walls are normally considered as non-structural elements. However these walls are effective in carrying lateral loads. In this regard, an experimental investigation was planned and conducted to study the effect of braced Reinforced Concrete (R.C.) frames in contrast to the bare frames. All these frames were tested up to collapse and subjected to only horizontal loads to obtain an efficient and probable solution for soft storey. In comparison to bare R.C. frames, steel braced R.C. frames have an increase by a notable amount for stiffness and ultimate lateral load capacity. Central braced system is additional effectual than that of corner and diagonal braced system. For the similar load braced R.C. frames have considerable less deflection than that of the bare R.C. frames. The contribution of central and diagonal bracing in comparison to corner bracing is observed to be 20% and 50% correspondingly. The percentage increase in stiffness for braced frames in comparison to bare R...
The effect of elevated temperature, its duration and cooling condition on compressive and flexura... more The effect of elevated temperature, its duration and cooling condition on compressive and flexural strength of concrete is a complex phenomenon and its characterization is governed by several other parameters related to concrete. The destructive testing of concrete subjected to elevated temperature for evaluating its compressive and flexural strength consumes time and put constraints on field schedules and hence there is need to develop the mathematical model which can provide an accurate range of results based on previous data. This paper presents the capability and application of dimensional analysis using Buckingham’s 𝜋 theorem approach for predicting compressive and flexural strength of M-20 and M-40 grade concrete subjected to elevated temperature. A mathematical model is developed using Buckingham’s 𝜋 theorem. The functional relationship of variables of concrete is expressed in the form of an exponential equation which is dimensionally homogeneous. A dimensional constant is de...
Due to tremor buildings are damaged partly or totally. Predominantly soft storeys are mostly affe... more Due to tremor buildings are damaged partly or totally. Predominantly soft storeys are mostly affected. In general such structures are repaired and used again. In this regard, an experimental investigation was planned and conducted for bare R.C. (Reinforced concrete) frames up to collapse and then such collapsed frames repaired with epoxy resin were tested to obtain ultimate load and results are compared. All these frames were tested up to collapse and subjected to only horizontal loads to obtain an effective and possible solution for retrofitted frames which can be reused for soft storeys. In comparison to bare R.C. frames, epoxy repaired frames have comparable lateral load capacity. For the similar load epoxy repaired frames have maximum deformation under control in comparision to bare R.C.frames.
Bamboo is a giant grass and not a tree. Bamboo completes its growth within some months and mature... more Bamboo is a giant grass and not a tree. Bamboo completes its growth within some months and matures at the age of around three years, there is no secondary growth. Moisture content of bamboo varies along its height location and with seasoning period, which affects all physical and mechanical properties. It is one of the important factors in deciding the life of bamboo. This paper presents results of experimental investigations made to evaluate the physical and mechanical properties of the bamboo species Dendrocalamus strictus and its utilization potential as building material may be as whole or in the split form. In the present study moisture content, specific gravity, water absorption, dimensional changes, tensile and compressive strength at different height location are worked out. The moisture content varies along the height for green bamboo or at any time after harvesting. The top portions had consistently lower moisture content than the middle or basal at all stages of seasoning...
A large numbers of buildings are constructed with masonry infill for functional or aesthetic reas... more A large numbers of buildings are constructed with masonry infill for functional or aesthetic reasons. S ometimes window or ventilator openings have been left in the wall for architectural necessities. Constructions with such partial masonry infill face serious earthquake shear damages in columns due to captive-column effect. Due to complex behavior of partial infill structures are analyzed and designed as bare frames. The purpose of this research is to investigate the behavior of steel frames by using steel bracing under lateral loading and to reduce the potential for capti ve-column damage. An experimental study is carried out on single, single storey for steel frames with bare, corner, central and horizontal steel bracing.All such frames were tested up to collapse and subjected only to horizontal loads to obtain an effective and possible solution for captive column.In comparison to bare, braced frames have significant increase in lateral load capacity. Central bracing is more effe...
International Journal of Innovative Research in Science, Engineering and Technology, 2014
Number of buildings is constructed with partial masonry infill for serviceable or artistic reason... more Number of buildings is constructed with partial masonry infill for serviceable or artistic reasons. Sometimes openings have been left a window or ventilator in the wall for architectural necessities. Constructions with such partial masonry infill face serious damages because of captive-column effect at the time of earthquake. Due to complex behavior of partial infill, structures are analyzed and designed as bare frames. The purpose of this research is to investigate the behavior of Reinforced Concrete (R.C.) frames by using steel bracing under horizontal loading and to decrease the potential for captive-column damage. An experimental study is carried out on single, single storey for R.C. frames with bare and corner steel bracing. All such frames were tested up to collapse and subjected only to monotonic static lateral load to obtain an effective and possible solution for captive column. In comparison to bare, braced frames have noteworthy increase in lateral load capacity. Central b...
Indian journal of applied research, 2011
Gayatri R. Gadekar Dr. Sunil Kute
International Journal of Engineering and Advanced Technology, 2020
Ferrocement is one of the most inexpensive and alternative construction techniques. The beauty of... more Ferrocement is one of the most inexpensive and alternative construction techniques. The beauty of this materials attracts in analyzing and designing the ferrocement (F.C.) silo. This has encouraged the search for new materials like F.C. to provide an alternative to reinforced concrete. During last two decades, many attempts have been made to develop computational models for analysis of silos particularly in steel and reinforced cement concrete. However, very less work is reported on scientific development of analysis of F.C. silo. This indicates that there is a need to continue with more focus and detailed research on F.C. silo. There is a need to analyze F.C. silo for various parametric findings related to pressure and behavior of silo in tension, compression and flexure. Present paper reports new aspects of analysis of silo. The parametric study of stresses developed in wall of F.C. silo for different H/D ratio, thickness and storage capacity is done with help of commercial ANSYS ...
International Journal of Advanced Structural Engineering, 2018
SRCFT columns are formed by inserting a steel section into a concrete-filled steel tube. These ty... more SRCFT columns are formed by inserting a steel section into a concrete-filled steel tube. These types of columns are named steel-reinforced concrete-filled steel tubular (SRCFT) columns. The current study aims at investigating the various types of reinforcing steel section to improve the strength and hysteresis behavior of SRCFT columns under axial and lateral cyclic loading. To attain this objective, a numerical study has been conducted on a series of composite columns. First, FEM procedure has been verified by the use of available experimental studies. Next, eight composite columns having different types of cross sections were analyzed. For comparison purpose, the base model was a CFT column used as a benchmark specimen. Nevertheless, the other specimens were SRCFT types. The results indicate that reinforcement of a CFT column through this method leads to enhancement in load-carrying capacity, enhancement in lateral drift ratio, ductility, preventing of local buckling in steel shell, and enhancement in energy absorption capacity. Under cyclic displacement history, it was observed that the use of cross-shaped reinforcing steel section causes a higher level of energy dissipation and the moment of inertia of the reinforcing steel sections was found to be the most significant parameter affecting the hysteresis behavior of SRCFT columns.
World Journal of Engineering, 2018
Purpose The main function of the castellation process is making I-sections stiffer by increasing ... more Purpose The main function of the castellation process is making I-sections stiffer by increasing the height of web and supplying a higher moment capacity of primary axis than plain-webbed members of the same weight. In addition, it optimizes the use of heavy, costly constructional steel material and provides good services accessibility. The purpose of this study was to investigate the strength and buckling behavior of axially loaded castellated cruciform steel columns using finite element analysis. Although a significant body of research exists on the failure of different columns, there is no proper criterion introduced to determine the point of buckling in the equilibrium path of an imperfect column. Design/methodology/approach This paper considers a wide range of practical geometric dimensions and various end conditions using ANSYS software. Findings are reported for about 224 samples of castellated cruciform I-shaped sections, and a simplified approach to evaluate buckling capacity of castellated columns, using the slenderness-load curve, is developed. In addition, the axial compressive capacities of those steel sections are investigated numerically in the current study. Findings The results of nonlinear analyses of these columns revealed that the load-carrying capacity of castellated cruciform steel columns far outweighs and is more appropriate than that of the traditional cruciform steel columns. In the present paper, new geometric criteria have been introduced having the ability to cover different types of columns. It shows the critical load of columns in the range of elastic and inelastic behavior. Practical implications This study can provide a background for practical engineering applications and design specifications for steel structures with castellated sections. In the present paper, new geometric criteria have been introduced having the ability to cover different types of columns. It shows the critical load of columns showing both elastic and inelastic behavior. Because this method showed reliable performance, it can be used during experimental tests for detecting buckling point. Originality/value This study can provide background for practical engineering applications and design specifications for steel structures with castellated sections; also, a physical criterion has been defined for calculating the buckling load of real columns.
Engineering Structures, 2018
The additive model of shear strength of reinforced concrete (RC) members, i.e. shear strength (V)... more The additive model of shear strength of reinforced concrete (RC) members, i.e. shear strength (V) is equal to the sum of the contribution from concrete (V c) and that from transverse reinforcement (V s), has been widely accepted in the literature and engineering practice. Shear span-to-depth ratio (a/d) is known to be a significant factor affecting V of RC members. However, very few quantitative studies on the influence of a/d on V c and V s have been reported in the literature. Another issue is related to the controversial relationship between the shear force at first diagonal cracking (V cr) and V c , for which different guidelines are given in ACI, AASHTO LRFD and CSA codes. Through direct measurement of V c and V s from 11 RC beam tests, this work provides experimental evidence for these issues. The experimental results show that V c can be very different from V cr. At small shear span-to-depth ratio (a/d), V c is much larger than V cr , while it is the opposite for beams with a large a/d value. Not all stirrups crossing the critical shear crack yield at ultimate shear strength, and V c as well as V s are not constant under increasing member deformation. Although design codes give a conservative prediction of V, they predict an un-conservative value of V c at large a/d.
Journal of Civil Engineering and Science, 2015
Optimal proportions of concrete mix ingredients are vital for establishing a relationship between... more Optimal proportions of concrete mix ingredients are vital for establishing a relationship between the best particle distribution and the corresponding degree of packing. The maximum strength is attained when the porosity of the granular structure is minimal to the minimum voids ratio. Concrete is a particulate material, and the particle-packing theory has significance when designing a concrete mix. The objective of this work was to produce an optimum concrete mix of required design stipulations based on combinations of optimized aggregate grading and effective estimation of the required water and cement. The present work investigated the potential of the particle-packing phenomenon to optimize the cement and water content and improve concrete properties with an "aggregate to paste" approach.