The present analysis demonstrates the thermal effect on vibrations of a symmetric, non-homoge- neous trapezoidal plate with parabolically varying thickness in both directions. The variation in Young’s modulus and mas...The present analysis demonstrates the thermal effect on vibrations of a symmetric, non-homoge- neous trapezoidal plate with parabolically varying thickness in both directions. The variation in Young’s modulus and mass density is the main cause for the occurrence of non-homogeneity in plate’s material. In this consideration, density varies linearly in one direction. The governing differential equations have been derived by Rayleigh-Ritz method in order to attain fundamental frequencies. With C-S-C-S boundary condition, a two term deflection function has been considered. The effect of structural parameters such as taper constants, thermal gradient, aspect ratio and non-homogeneity constant has been investigated for first two modes of vibration. The obtained numerical results have been presented in tabular and graphical form.展开更多
The main aim of the present work is to study the linear temperature behaviour of a non-homogeneous trapezoidal plate whose thickness varies linearly in both directions. The temperature behaviour considered linear alon...The main aim of the present work is to study the linear temperature behaviour of a non-homogeneous trapezoidal plate whose thickness varies linearly in both directions. The temperature behaviour considered linear along the length of the plate. Non-homogeneity in plate arises due to variation in density along the length of the plate. The two-term deflection function with clamped-simply supported-clamped-simply supported boundary condition is taken into consideration. The effect of structural parameters such as taper constants, thermal gradient, non-homogeneity constant and aspect ratio has been studied. Rayleigh-Ritz method is used to solve the governing differential equations and to obtain the fundamental frequencies for the first two modes of vibration. Results are presented in graphical form.展开更多
Cutouts are inevitable in structures due to practical consideration.In order to investigate the free vibration of functionally graded plates with multiple circular and non-circular cutouts,finite element method is use...Cutouts are inevitable in structures due to practical consideration.In order to investigate the free vibration of functionally graded plates with multiple circular and non-circular cutouts,finite element method is used.The volume fraction of the material constituents is assumed to follow a simple power law distribution.The parameters considered in this paper are as follows:cutout size,cutout location,number of cutouts and different boundary conditions.It should be mentioned that free vibration for FG plates(such as rectangular?skew?trapezoidal?circular plates) with multiple cutouts has not been studied yet and hence the results out coming from this paper may be used as bench marks for future works.展开更多
In this study,a new system consisting of a combination of braces and steel infill panels called the braced corrugated steel shear panel(BCSSP)is presented.To obtain the hysteretic behavior of the proposed system,the q...In this study,a new system consisting of a combination of braces and steel infill panels called the braced corrugated steel shear panel(BCSSP)is presented.To obtain the hysteretic behavior of the proposed system,the quasistatic cyclic performances of two experimental specimens were first evaluated.The finite element modeling method was then verified based on the obtained experimental results.Additional numerical evaluations were carried out to investigate the effects of different parameters on the system.Subsequently,a relationship was established to estimate the buckling shear strength of the system without considering residual stresses.The results obtained from the parametric study indicate that the corrugated steel shear panel(CSSP)with the specifications of a=30 mm,t=2 mm,andθ=90°had the highest energy dissipation capacity and ultimate strength while the CSSP with the specifications of a=30 mm,t=2 mm,andθ=30°had the highest initial stiffness.It can thus be concluded that the latter CSSP has the best structural performance and that increasing the number of corrugations,corrugation angle,and plate thickness and decreasing the sub-panel width generally enhance the performance of CSSPs in terms of the stability of their hysteretic behaviors.展开更多
An effective 3D supersonic Mach box approach in combination with non-classical hybrid metal-composite plate theory has been used to investigate flutter boundaries of trapezoidal low aspect ratio wings. The wing struct...An effective 3D supersonic Mach box approach in combination with non-classical hybrid metal-composite plate theory has been used to investigate flutter boundaries of trapezoidal low aspect ratio wings. The wing structure is composed of two main components including aluminum material(in-board section) and laminated composite material(out-board section). A global Ritz method is used with simple polynomials being employed as the trial functions. The most important objective of the present research is to study the effect of composite to metal proportion of hybrid wing structure on flutter boundaries in low supersonic regime. In addition, the effect of some important geometrical parameters such as sweep angle, taper ratio and aspect ratio on flutter boundaries were studied. The results obtained by present approach for special cases like pure metallic wings and results for high supersonic regime based on piston theory show a good agreement with those obtained by other investigators.展开更多
文摘The present analysis demonstrates the thermal effect on vibrations of a symmetric, non-homoge- neous trapezoidal plate with parabolically varying thickness in both directions. The variation in Young’s modulus and mass density is the main cause for the occurrence of non-homogeneity in plate’s material. In this consideration, density varies linearly in one direction. The governing differential equations have been derived by Rayleigh-Ritz method in order to attain fundamental frequencies. With C-S-C-S boundary condition, a two term deflection function has been considered. The effect of structural parameters such as taper constants, thermal gradient, aspect ratio and non-homogeneity constant has been investigated for first two modes of vibration. The obtained numerical results have been presented in tabular and graphical form.
文摘The main aim of the present work is to study the linear temperature behaviour of a non-homogeneous trapezoidal plate whose thickness varies linearly in both directions. The temperature behaviour considered linear along the length of the plate. Non-homogeneity in plate arises due to variation in density along the length of the plate. The two-term deflection function with clamped-simply supported-clamped-simply supported boundary condition is taken into consideration. The effect of structural parameters such as taper constants, thermal gradient, non-homogeneity constant and aspect ratio has been studied. Rayleigh-Ritz method is used to solve the governing differential equations and to obtain the fundamental frequencies for the first two modes of vibration. Results are presented in graphical form.
文摘Cutouts are inevitable in structures due to practical consideration.In order to investigate the free vibration of functionally graded plates with multiple circular and non-circular cutouts,finite element method is used.The volume fraction of the material constituents is assumed to follow a simple power law distribution.The parameters considered in this paper are as follows:cutout size,cutout location,number of cutouts and different boundary conditions.It should be mentioned that free vibration for FG plates(such as rectangular?skew?trapezoidal?circular plates) with multiple cutouts has not been studied yet and hence the results out coming from this paper may be used as bench marks for future works.
文摘In this study,a new system consisting of a combination of braces and steel infill panels called the braced corrugated steel shear panel(BCSSP)is presented.To obtain the hysteretic behavior of the proposed system,the quasistatic cyclic performances of two experimental specimens were first evaluated.The finite element modeling method was then verified based on the obtained experimental results.Additional numerical evaluations were carried out to investigate the effects of different parameters on the system.Subsequently,a relationship was established to estimate the buckling shear strength of the system without considering residual stresses.The results obtained from the parametric study indicate that the corrugated steel shear panel(CSSP)with the specifications of a=30 mm,t=2 mm,andθ=90°had the highest energy dissipation capacity and ultimate strength while the CSSP with the specifications of a=30 mm,t=2 mm,andθ=30°had the highest initial stiffness.It can thus be concluded that the latter CSSP has the best structural performance and that increasing the number of corrugations,corrugation angle,and plate thickness and decreasing the sub-panel width generally enhance the performance of CSSPs in terms of the stability of their hysteretic behaviors.
文摘An effective 3D supersonic Mach box approach in combination with non-classical hybrid metal-composite plate theory has been used to investigate flutter boundaries of trapezoidal low aspect ratio wings. The wing structure is composed of two main components including aluminum material(in-board section) and laminated composite material(out-board section). A global Ritz method is used with simple polynomials being employed as the trial functions. The most important objective of the present research is to study the effect of composite to metal proportion of hybrid wing structure on flutter boundaries in low supersonic regime. In addition, the effect of some important geometrical parameters such as sweep angle, taper ratio and aspect ratio on flutter boundaries were studied. The results obtained by present approach for special cases like pure metallic wings and results for high supersonic regime based on piston theory show a good agreement with those obtained by other investigators.
