Inspired by living organisms,helicoidal structures are becoming increasingly important in replacing the conventional lamination scheme to enhance the toughness,strength,and stiffness of laminates.In helicoidal laminat...Inspired by living organisms,helicoidal structures are becoming increasingly important in replacing the conventional lamination scheme to enhance the toughness,strength,and stiffness of laminates.In helicoidal laminated composites,each layer is rotated by a specific angle with respect to the previous layer.In the present study,an attempt has been carried out to compare the free vibration and buckling behavior of the double-helicoidal and cross-helicoidal bio-inspired laminated composite plates under thermal conditions.The influence of lamination scheme,aspect ratio,end conditions,thermal conditions,sideto-thickness ratio,and skew angle on the free vibration and buckling behavior of the plate is investigated.The performance of helicoidal laminated composite plates is compared with that of cross-ply and quasi-isotropic laminates.The study reveals that the helicoidal composites outperform the cross-ply and quasi-isotropic laminates.In most cases studied,the cross-helicoidal plate exhibits stiff behavior.展开更多
In the present work,free vibration and buckling analyses of sandwich plates with various functionally graded foam cores are carried out.Foam cores are assumed to be made of metal,and three different configurations of ...In the present work,free vibration and buckling analyses of sandwich plates with various functionally graded foam cores are carried out.Foam cores are assumed to be made of metal,and three different configurations of the porous distribution in the core layer are taken into consideration.To carry out a comparative study between the distributions of pores in the core foam,the mass of foam in all three cases is kept the same.The vibration and buckling behaviors of skew plates are also analyzed as a part of the current investigation.The principle of minimization of potential energy and Hamilton’s principle are used for the derivation of the governing equations,while a C-0 finite element-based higher-order zigzag formulation is developed to solve the free vibration and buckling problems.The influences of gradation laws,boundary conditions,skew angle and geometry of plates are studied in detail for the dynamic and stability characteristics.It is found that both the non-dimensional natural frequency and buckling load decrease with the increase in the thickness of the metal foam cores,while they show an increasing trend as the skew angle of the plate increases.展开更多
Most of the materials used in engineered cementitious composite are fine in size to achieve ductile nature.Stone slurry powder(SSP)is an inert material obtained from stone industries as by-product which may cause haza...Most of the materials used in engineered cementitious composite are fine in size to achieve ductile nature.Stone slurry powder(SSP)is an inert material obtained from stone industries as by-product which may cause hazardous impact on environment.In this research work,partial replacement of silica sand(SS)and fine sand(FS)by SSP with different contents(25%and 50%each)for making engineered cementitious composite has been explored.The performance was evaluated on the basis of strength,tensile strain,mid span deflection capacity,ultra-sonic pulse velocity and microstructure.Mechanical strength was found to be increased at 25%SSP in both replacements;whereas,strength decreased slightly at 50%replacement.Tensile strain,mid span deflection and quality of concrete were enhanced with increase in SSP content.Using SSP formed denser cementitious composite can help to save the natural resources and contribute in making green cementitious composite.展开更多
文摘Inspired by living organisms,helicoidal structures are becoming increasingly important in replacing the conventional lamination scheme to enhance the toughness,strength,and stiffness of laminates.In helicoidal laminated composites,each layer is rotated by a specific angle with respect to the previous layer.In the present study,an attempt has been carried out to compare the free vibration and buckling behavior of the double-helicoidal and cross-helicoidal bio-inspired laminated composite plates under thermal conditions.The influence of lamination scheme,aspect ratio,end conditions,thermal conditions,sideto-thickness ratio,and skew angle on the free vibration and buckling behavior of the plate is investigated.The performance of helicoidal laminated composite plates is compared with that of cross-ply and quasi-isotropic laminates.The study reveals that the helicoidal composites outperform the cross-ply and quasi-isotropic laminates.In most cases studied,the cross-helicoidal plate exhibits stiff behavior.
基金supporting the present work through Ph.D.scholarship grant(2K17/NITK/PHD/6170004).Tanmoy Mukhopadhyay acknowledges SERB,India,for providing research support through the grant SERB/AE/2020316.
文摘In the present work,free vibration and buckling analyses of sandwich plates with various functionally graded foam cores are carried out.Foam cores are assumed to be made of metal,and three different configurations of the porous distribution in the core layer are taken into consideration.To carry out a comparative study between the distributions of pores in the core foam,the mass of foam in all three cases is kept the same.The vibration and buckling behaviors of skew plates are also analyzed as a part of the current investigation.The principle of minimization of potential energy and Hamilton’s principle are used for the derivation of the governing equations,while a C-0 finite element-based higher-order zigzag formulation is developed to solve the free vibration and buckling problems.The influences of gradation laws,boundary conditions,skew angle and geometry of plates are studied in detail for the dynamic and stability characteristics.It is found that both the non-dimensional natural frequency and buckling load decrease with the increase in the thickness of the metal foam cores,while they show an increasing trend as the skew angle of the plate increases.
基金Project(F1-17.1/2017-18/MANF-2017-18-HAR-78129)supported by the University Grants Commission New Delhi,India。
文摘Most of the materials used in engineered cementitious composite are fine in size to achieve ductile nature.Stone slurry powder(SSP)is an inert material obtained from stone industries as by-product which may cause hazardous impact on environment.In this research work,partial replacement of silica sand(SS)and fine sand(FS)by SSP with different contents(25%and 50%each)for making engineered cementitious composite has been explored.The performance was evaluated on the basis of strength,tensile strain,mid span deflection capacity,ultra-sonic pulse velocity and microstructure.Mechanical strength was found to be increased at 25%SSP in both replacements;whereas,strength decreased slightly at 50%replacement.Tensile strain,mid span deflection and quality of concrete were enhanced with increase in SSP content.Using SSP formed denser cementitious composite can help to save the natural resources and contribute in making green cementitious composite.
