TY - GEN
T1 - Local optimisation of anisotropic composite panels with T shape stiffeners
AU - Herencia, J. Enrique
AU - Weaver, Paul M.
AU - Friswell, Michael I.
PY - 2007
Y1 - 2007
N2 - A method to locally optimise anisotropic composite panels with T shape stiffeners is provided. The technique divides the optimisation problem into two levels. At the first level, composite optimisation is performed using Mathematical Programming (MP), where the skin and the stiffeners are modelled using lamination parameters accounting for their anisotropy and transverse shear stiffness. Skin and stiffener laminates are assumed to be symmetric, or mid-plane symmetric laminates with 0, 90, 45 or -45 degree ply angles. The stiffened panel is subjected to a combined loading (in-plane and out-of-plane) under strength (laminate or ply failure), buckling and practical design constraints. Out-of-plane loading is caused by lateral pressure, initial geometric imperfections and eccentricities in the in-plane loading. The manufacture of the stiffener is embedded within the design variables. Ply contiguity constraints are imposed at this level to improve convergence towards a practical laminate design. At the second level, the actual skin and stiffener lay-ups are obtained using a Genetic Algorithm (GA), accounting for manufacturability and design practices. This approach benefits from MP at the first level where complex structural analysis is performed and from GA at the second level where the discrete lay-up combinational problem is solved. Moreover, modelling laminate anisotropy enables engineers to explore and potentially use elastic tailoring to their advantage.
AB - A method to locally optimise anisotropic composite panels with T shape stiffeners is provided. The technique divides the optimisation problem into two levels. At the first level, composite optimisation is performed using Mathematical Programming (MP), where the skin and the stiffeners are modelled using lamination parameters accounting for their anisotropy and transverse shear stiffness. Skin and stiffener laminates are assumed to be symmetric, or mid-plane symmetric laminates with 0, 90, 45 or -45 degree ply angles. The stiffened panel is subjected to a combined loading (in-plane and out-of-plane) under strength (laminate or ply failure), buckling and practical design constraints. Out-of-plane loading is caused by lateral pressure, initial geometric imperfections and eccentricities in the in-plane loading. The manufacture of the stiffener is embedded within the design variables. Ply contiguity constraints are imposed at this level to improve convergence towards a practical laminate design. At the second level, the actual skin and stiffener lay-ups are obtained using a Genetic Algorithm (GA), accounting for manufacturability and design practices. This approach benefits from MP at the first level where complex structural analysis is performed and from GA at the second level where the discrete lay-up combinational problem is solved. Moreover, modelling laminate anisotropy enables engineers to explore and potentially use elastic tailoring to their advantage.
UR - http://www.scopus.com/inward/record.url?scp=34547496235&partnerID=8YFLogxK
U2 - 10.2514/6.2007-2217
DO - 10.2514/6.2007-2217
M3 - Conference contribution
AN - SCOPUS:34547496235
SN - 1563478927
SN - 9781563478925
T3 - Collection of Technical Papers - AIAA/ASME/ASCE/AHS/ASC Structures, Structural Dynamics and Materials Conference
SP - 6241
EP - 6267
BT - Collection of Technical Papers - 48th AIAA/ASME/ASCE/AHS/ASC Structures, Structural Dynamics, and Materials Conference
PB - American Institute of Aeronautics and Astronautics Inc.
T2 - 48th AIAA/ASME/ASCE/AHS/ASC Structures, Structural Dynamics, and Materials Conference
Y2 - 23 April 2007 through 26 April 2007
ER -