Nature and technology often adopt structures that can be described as tubular helical assemblies.However,the role and mechanisms of these structures remain elusive.In this paper,we study the mechanical response under ...Nature and technology often adopt structures that can be described as tubular helical assemblies.However,the role and mechanisms of these structures remain elusive.In this paper,we study the mechanical response under compression and extension of a tubular assembly composed of 8 helical Kirchholf rods,arranged in pairs with opposite chirality and connected by pin joints,both analytically and numerically.We first focus on compression and find that,whereas a single helical rod would buckle,the rods of the assembly deform coherently as stable helical shapes wound around a common axis.Moreover,we investigate the response of the assembly under different boundary conditions,highlighting the emergence of a central region where rods remain circular helices.Secondly,we study the effects of different hypotheses on the elastic properties of rods,i.e.,stress-free rods when straight versus when circular helices,Kirchhoff’s rod model versus Sadowsky’s ribbon model.Summing up,our findings highlight the key role of mutual interactions in generating a stable ensemble response that preserves the helical shape of the individual rods,as well as some interesting features,and they shed some light on the reasons why helical shapes in tubular assemblies are so common and persistent in nature and technology.展开更多
As originally proposed by professor Alberto Corigliano of Politecnico di Milano and professor Jizeng Wang of Lanzhou University,the Chinese Society of Theoretical and Applied Mechanics(CSTAM)and the Italian Associatio...As originally proposed by professor Alberto Corigliano of Politecnico di Milano and professor Jizeng Wang of Lanzhou University,the Chinese Society of Theoretical and Applied Mechanics(CSTAM)and the Italian Association for Theoretical and Applied Mechanics(AIMETA)signed a memorandum of understanding on strengthening exchange and cooperation between mechanics scholars of the two countries in January,2018,officially opening the activities of bilateral academic exchange.展开更多
基金Open access funding provided by Scuola Superiore Sant’Anna within the CRUI-CARE Agreement.
文摘Nature and technology often adopt structures that can be described as tubular helical assemblies.However,the role and mechanisms of these structures remain elusive.In this paper,we study the mechanical response under compression and extension of a tubular assembly composed of 8 helical Kirchholf rods,arranged in pairs with opposite chirality and connected by pin joints,both analytically and numerically.We first focus on compression and find that,whereas a single helical rod would buckle,the rods of the assembly deform coherently as stable helical shapes wound around a common axis.Moreover,we investigate the response of the assembly under different boundary conditions,highlighting the emergence of a central region where rods remain circular helices.Secondly,we study the effects of different hypotheses on the elastic properties of rods,i.e.,stress-free rods when straight versus when circular helices,Kirchhoff’s rod model versus Sadowsky’s ribbon model.Summing up,our findings highlight the key role of mutual interactions in generating a stable ensemble response that preserves the helical shape of the individual rods,as well as some interesting features,and they shed some light on the reasons why helical shapes in tubular assemblies are so common and persistent in nature and technology.
基金We appreciate the efforts made by all the contributors for this thematic issue.We are grateful to the former Editor-in-Chief of Acta Mechanica Sinica,Prof.Tian Jian Lu,for inviting us as the guest editors of this issue.We also thank the current Editor-in-Chief Prof.Xiaojing Zheng and the former president of the CSTAM,Prof.Wei Yang,for their encouraging and support,and staff of the editorial office of Acta Mechanica Sinica for managing and assistance.J.Z.Wang thanks the support from the National Natural Science Foundation of China(Grant 11925204).
文摘As originally proposed by professor Alberto Corigliano of Politecnico di Milano and professor Jizeng Wang of Lanzhou University,the Chinese Society of Theoretical and Applied Mechanics(CSTAM)and the Italian Association for Theoretical and Applied Mechanics(AIMETA)signed a memorandum of understanding on strengthening exchange and cooperation between mechanics scholars of the two countries in January,2018,officially opening the activities of bilateral academic exchange.
