The Experts below are selected from a list of 7590 Experts worldwide ranked by ideXlab platform
Nguyen Dinh Duc - One of the best experts on this subject based on the ideXlab platform.
-
nonlinear thermo mechanical response of eccentrically stiffened sigmoid fgm circular cylindrical shells subjected to Compressive and uniform radial Loads using the reddy s third order shear deformation shell theory
Mechanics of Advanced Materials and Structures, 2018Co-Authors: Nguyen Dinh Duc, Nguyen Dinh Khoa, Hoang Thi ThiemAbstract:Based on Reddy's third-order shear deformation shell theory, this paper presents an analytical approach to investigate the nonlinear thermo-mechanical response of imperfect Sigmoid FGM circular cylindrical shells surrounded on elastic foundations and reinforced by outside metal stiffeners. The eccentrically stiffened S-FGM shells are subjected to Axial Compressive Load and uniform radial Load in thermal environment. Using the stress function, Bubnov–Galerkin method, the paper proposes the formula for forces and moments taking into account the thermal stress in both the shells and stiffeners. The obtained results are validated by comparing with other results reported in the literature.
-
nonlinear thermo mechanical response of eccentrically stiffened sigmoid fgm circular cylindrical shells subjected to Compressive and uniform radial Loads using the reddy s third order shear deformation shell theory
Mechanics of Advanced Materials and Structures, 2018Co-Authors: Nguyen Dinh Duc, Nguyen Dinh Khoa, Hoang Thi ThiemAbstract:AbstractBased on Reddy's third-order shear deformation shell theory, this paper presents an analytical approach to investigate the nonlinear thermo-mechanical response of imperfect Sigmoid FGM circular cylindrical shells surrounded on elastic foundations and reinforced by outside metal stiffeners. The eccentrically stiffened S-FGM shells are subjected to Axial Compressive Load and uniform radial Load in thermal environment. Using the stress function, Bubnov–Galerkin method, the paper proposes the formula for forces and moments taking into account the thermal stress in both the shells and stiffeners. The obtained results are validated by comparing with other results reported in literature.
-
nonlinear dynamic response of imperfect eccentrically stiffened fgm double curved shallow shells on elastic foundation
Composite Structures, 2013Co-Authors: Nguyen Dinh DucAbstract:Abstract This paper presents an analytical investigation on the nonlinear dynamic response of eccentrically stiffened functionally graded double curved shallow shells resting on elastic foundations and being subjected to Axial Compressive Load and transverse Load. The formulations are based on the classical shell theory taking into account geometrical nonlinearity, initial geometrical imperfection and the Lekhnitsky smeared stiffeners technique with Pasternak type elastic foundation. The non-linear equations are solved by the Runge-Kutta and Bubnov-Galerkin methods. Obtained results show effects of material and geometrical properties, elastic foundation and imperfection on the dynamical response of reinforced FGM shallow shells. Some numerical results are given and compared with ones of other authors.
Hoang Thi Thiem - One of the best experts on this subject based on the ideXlab platform.
-
nonlinear thermo mechanical response of eccentrically stiffened sigmoid fgm circular cylindrical shells subjected to Compressive and uniform radial Loads using the reddy s third order shear deformation shell theory
Mechanics of Advanced Materials and Structures, 2018Co-Authors: Nguyen Dinh Duc, Nguyen Dinh Khoa, Hoang Thi ThiemAbstract:Based on Reddy's third-order shear deformation shell theory, this paper presents an analytical approach to investigate the nonlinear thermo-mechanical response of imperfect Sigmoid FGM circular cylindrical shells surrounded on elastic foundations and reinforced by outside metal stiffeners. The eccentrically stiffened S-FGM shells are subjected to Axial Compressive Load and uniform radial Load in thermal environment. Using the stress function, Bubnov–Galerkin method, the paper proposes the formula for forces and moments taking into account the thermal stress in both the shells and stiffeners. The obtained results are validated by comparing with other results reported in the literature.
-
nonlinear thermo mechanical response of eccentrically stiffened sigmoid fgm circular cylindrical shells subjected to Compressive and uniform radial Loads using the reddy s third order shear deformation shell theory
Mechanics of Advanced Materials and Structures, 2018Co-Authors: Nguyen Dinh Duc, Nguyen Dinh Khoa, Hoang Thi ThiemAbstract:AbstractBased on Reddy's third-order shear deformation shell theory, this paper presents an analytical approach to investigate the nonlinear thermo-mechanical response of imperfect Sigmoid FGM circular cylindrical shells surrounded on elastic foundations and reinforced by outside metal stiffeners. The eccentrically stiffened S-FGM shells are subjected to Axial Compressive Load and uniform radial Load in thermal environment. Using the stress function, Bubnov–Galerkin method, the paper proposes the formula for forces and moments taking into account the thermal stress in both the shells and stiffeners. The obtained results are validated by comparing with other results reported in literature.
-
dynamic analysis of imperfect fgm circular cylindrical shells reinforced by fgm stiffener system using third order shear deformation theory in term of displacement components
Latin American Journal of Solids and Structures, 2017Co-Authors: Dao Van Dung, Hoang Thi ThiemAbstract:THIS PAPER PRESENTS DYNAMIC ANALYSIS OF AN ECCENTRICALLY STIFFENED IMPERFECT CIRCULAR CYLINDRICAL SHELLS MADE OF FUNCTIONALLY GRADED MATERIALS, SUBJECTED TO Axial Compressive Load AND FILLED INSIDE BY ELASTIC FOUNDATIONS IN THERMAL ENVIRONMENTS BY ANALYTICAL METHOD. SHELLS ARE REINFORCED BY FGM STRINGERS AND RINGS TAKING INTO ACCOUNT THERMAL ELEMENTS. THE STABILITY EQUATIONS IN TERMS OF DISPLACEMENT COMPONENTS FOR STIFFENED SHELLS ARE DERIVED BY USING THE THIRD-ORDER SHEAR DEFORMATION THEORY AND SMEARED STIFFENERS TECHNIQUE. THE CLOSED-FORM EXPRESSIONS FOR DETERMINING THE NATURAL FREQUENCY, NONLINEAR FREQUENCY-AMPLITUDE CURVE AND NONLINEAR DYNAMIC RESPONSE ARE OBTAINED BY USING GALERKIN MET-HOD AND FOURTH-ORDER RUNGE-KUTTA METHOD. THE EFFECTS OF STIFFENERS, FOUNDATIONS, IMPERFECTION, MATERIAL AND DIMENSIONAL PARA-METERS PRE-EXISTENT Axial Compressive AND THERMAL Load ON DYNAMIC RESPONSES OF SHELLS ARE CONSIDERED.
Ralejs Tepfers - One of the best experts on this subject based on the ideXlab platform.
-
behaviour and capacity of cfrp confined concrete cylinders subjected to monotonic and cyclic Axial Compressive Load
Structural Concrete, 2007Co-Authors: Vilis Valdmanis, L De Lorenzis, Theodoros C. Rousakis, Ralejs TepfersAbstract:The mechanical behaviour of concrete confined by carbon fibre reinforced polymer (CFRP) sheets is investigated in this study. Two series of tests were conducted on standard concrete cylinders with ...
-
Behaviour of concrete confined by high E-modulus carbon FRP sheets, subjected to monotonic and cyclic Axial Compressive Load
2004Co-Authors: Ralejs Tepfers, Theodoros C. RousakisAbstract:AbstractA systematic investigation is performed on the mechanical behavior of concrete cylinders (with Compressive cylinder strength 25.2 MPa and 51.8 MPa), confined by high E-modulus carbon fiber sheet (377 GPa). The concrete cylinders were wrapped with 1, 2, 3 and 5 layers of carbon FRP (fiber reinforced polymer) sheet and subjected to monotonic and cyclic Axial Compressive Loading. Teflon sheets were used between concrete and steel Loading plates to reduce friction. Pretests were made to estimate the proper overlap length of the external layer. The confining effect is addressed in terms of concrete strength, ductility and expansion. Considerable increase in levels of strength and strain at failure were achieved even for high strength concrete for monotonic and cyclic mode of Loading.
-
concrete cylinders confined by cfrp sheets subjected to cyclic Axial Compressive Load
Proceedings of the Sixth International Symposium on FRP Reinforcement for Concrete Structures (FRPRCS–6), 2003Co-Authors: Theodoros C. Rousakis, Chisang You, L De Lorenzis, V Tamužs, Ralejs TepfersAbstract:T. ROUSAKIS , C. S. YOU , L. DE LORENZIS , V. TAMUŽS , R. TEPFERS 5 1 Dept. of Civil Eng., Democritus University of Thrace, Xanthi, Greece 2 Dept. of Mechanical Eng., Pohang Univ. of Sci. and Tech., Pohang, South Korea 3 Dept. of Innovation Eng., University of Lecce, I-73100 Lecce, Italy 4 Institute of Polymer Mechanics, Univ. of Latvia, Aizkraukles 23, Riga, Latvia 5 Dept. of Building Materials, Chalmers University of Tech., Goteborg, Sweden
-
concrete cylinders confined by carbon frp sheets subjected to monotonic and cyclic Axial Compressive Load
6th International Symposium on Fibre Reinforced Polymer (FRP) Reinforcement for Concrete Structures (FRPRCS-6) 8-10 July 2003 Singapore., 2003Co-Authors: Ralejs Tepfers, Theodoros C. Rousakis, Chisang You, L De Lorenzis, V TamužsAbstract:During last decades, most RD 60.5; 76.2; 81.4 and 104.1MPa, that cover nearly the whole range in practice, were investigated. The parameters taken under consideration for the confinement were the number of layers (CFRP reinforcement ratio ranging from 0.31% to 0.94 %) for wrapping with carbon sheet with tensile strength 4500 MPa and modulus 234GPa. The friction between steel Loading plates and concrete surface was reduced by three layers of teflon sheet. The specimens were fully instrumented and apart from Load, Axial and lateral strains were measured, with LVDTs and strain gauges. The enhancement in strength and ductility of confined concrete was remarkable. The confined concrete displayed a distinct bilinear stress-strain response with transition zone around the ultimate strength of unconfined concrete. Maximum strength increase by the confinement was measured to be over 300% for specimen of 34.2MPa concrete. It is evident that as the CFRP layer number increases, the strength and ductility in the Axial direction are both improved. The slope of the branches after transition zone and confining pressure are depended on the volumetric ratio of the confining device. For higher concrete strength, the ultimate strength increase due to confinement was lower, which indicates that the confining pressure exerted by the composite material on the concrete surface, as a restriction of the lateral expansion of concrete, was not so effective for the high strength concrete, showing more brittle behavior. Cyclic Load caused no degradation in confining action. On the contrary sometimes caused improvement, which could be due to the fact that the confinement imposed lateral strain by its interaction with the concrete during unLoad stage too. So in the next Loading cycle the internal concrete cracks were uniformly developed in concrete mass and the Load distribution was better. Stress-strain relationships of the monotonic Load act like an envelope of that of cyclic Load since they have similar Loading paths. The confined concrete cylinders failed by fracture of the FRP confinement having lower lateral strain than the uniAxial ultimate tensile strain given by producer. CFRP ring test (ASTM standard D2290) reveal the real ultimate tensile strain of confinement, which only slightly exceeds the ultimate lateral strain. For the satisfactory prediction of strength, the stress analysis of crack growth inside concrete after transition zone should be accompanied by the analysis of confinement and its interaction with the damaged concrete.
Nguyen Dinh Khoa - One of the best experts on this subject based on the ideXlab platform.
-
nonlinear thermo mechanical response of eccentrically stiffened sigmoid fgm circular cylindrical shells subjected to Compressive and uniform radial Loads using the reddy s third order shear deformation shell theory
Mechanics of Advanced Materials and Structures, 2018Co-Authors: Nguyen Dinh Duc, Nguyen Dinh Khoa, Hoang Thi ThiemAbstract:Based on Reddy's third-order shear deformation shell theory, this paper presents an analytical approach to investigate the nonlinear thermo-mechanical response of imperfect Sigmoid FGM circular cylindrical shells surrounded on elastic foundations and reinforced by outside metal stiffeners. The eccentrically stiffened S-FGM shells are subjected to Axial Compressive Load and uniform radial Load in thermal environment. Using the stress function, Bubnov–Galerkin method, the paper proposes the formula for forces and moments taking into account the thermal stress in both the shells and stiffeners. The obtained results are validated by comparing with other results reported in the literature.
-
nonlinear thermo mechanical response of eccentrically stiffened sigmoid fgm circular cylindrical shells subjected to Compressive and uniform radial Loads using the reddy s third order shear deformation shell theory
Mechanics of Advanced Materials and Structures, 2018Co-Authors: Nguyen Dinh Duc, Nguyen Dinh Khoa, Hoang Thi ThiemAbstract:AbstractBased on Reddy's third-order shear deformation shell theory, this paper presents an analytical approach to investigate the nonlinear thermo-mechanical response of imperfect Sigmoid FGM circular cylindrical shells surrounded on elastic foundations and reinforced by outside metal stiffeners. The eccentrically stiffened S-FGM shells are subjected to Axial Compressive Load and uniform radial Load in thermal environment. Using the stress function, Bubnov–Galerkin method, the paper proposes the formula for forces and moments taking into account the thermal stress in both the shells and stiffeners. The obtained results are validated by comparing with other results reported in literature.
Jiing Sen Yang - One of the best experts on this subject based on the ideXlab platform.
-
Buckling optimization of laminated cylindrical panels subjected to Axial Compressive Load
Composite Structures, 2007Co-Authors: Jiing Sen YangAbstract:The buckling resistance of fiber-reinforced laminated cylindrical panels with a given material system and subjected to uniAxial Compressive force is maximized with respect to fiber orientations by using a sequential linear programming method together with a simple move-limit strategy. The significant influences of panel thicknesses, curvatures, aspect ratios, cutouts and end conditions on the optimal fiber orientations and the associated optimal buckling Loads of laminated cylindrical panels have been shown through this investigation.
