TY - JOUR
T1 - On application of catenary principles to sandwich structure design—Sandwich/ catenary hybrid beams under uniformly distributed load
AU - Kepler, Jørgen Asbøll
PY - 2020/2
Y1 - 2020/2
N2 - Application of catenary principles to sandwich structure design, whereby one face sheet follows the equilibrium shape of a catenary according to the applied load, is investigated. The difference between load transfer through a sandwich beam and through a catenary is outlined. An initial comparison between an inclined elastic string and a sandwich core under shear deformation provides an indication of the potential stiffness advantages of catenary design. A stiffness comparison is made between an ordinary sandwich beam with thin, parallel face sheets, a catenary suspended by the end-points, and a sandwich/catenary hybrid. It is demonstrated that, for mass parity and a uniformly distributed load, and depending on the constituent materials moduli, the sandwich/catenary hybrid may be designed for superior stiffness. A numerical modeling method is outlined for evaluating the deflection of a catenary, and subsequently expanded to predict deflection of a sandwich/catenary hybrid beam. The method is verified through comparison with experimentally measured deflection. It is demonstrated that first-order shear deformable theory, commonly applied to sandwich structures, is inherently unsuited for describing the elastic response of sandwich/catenary hybrids. For a typical range of face-sheet/core moduli, comparisons of relative stiffness for parallel-face sandwich beams and sandwich/catenary hybrid beams are calculated over a range of core heights, for equivalent core height and equivalent core volume.
AB - Application of catenary principles to sandwich structure design, whereby one face sheet follows the equilibrium shape of a catenary according to the applied load, is investigated. The difference between load transfer through a sandwich beam and through a catenary is outlined. An initial comparison between an inclined elastic string and a sandwich core under shear deformation provides an indication of the potential stiffness advantages of catenary design. A stiffness comparison is made between an ordinary sandwich beam with thin, parallel face sheets, a catenary suspended by the end-points, and a sandwich/catenary hybrid. It is demonstrated that, for mass parity and a uniformly distributed load, and depending on the constituent materials moduli, the sandwich/catenary hybrid may be designed for superior stiffness. A numerical modeling method is outlined for evaluating the deflection of a catenary, and subsequently expanded to predict deflection of a sandwich/catenary hybrid beam. The method is verified through comparison with experimentally measured deflection. It is demonstrated that first-order shear deformable theory, commonly applied to sandwich structures, is inherently unsuited for describing the elastic response of sandwich/catenary hybrids. For a typical range of face-sheet/core moduli, comparisons of relative stiffness for parallel-face sandwich beams and sandwich/catenary hybrid beams are calculated over a range of core heights, for equivalent core height and equivalent core volume.
KW - Sandwich
KW - catenary
KW - deflection
KW - design
KW - modeling
KW - transverse load
UR - http://www.scopus.com/inward/record.url?scp=85042532985&partnerID=8YFLogxK
U2 - 10.1177/1099636217735473
DO - 10.1177/1099636217735473
M3 - Journal article
SN - 1099-6362
VL - 22
SP - 127
EP - 155
JO - Journal of Sandwich Structures & Materials
JF - Journal of Sandwich Structures & Materials
IS - 2
ER -