Sandwich Construction
Sandwich ConstructionEng. Marco LeiteProf. Manuel de
FreitasProf. Arlindo Silva 1NOV 20042Sandwich
ConstructionIntroduoLeis ConstitutivasExemploDesign
proceduresAplicaesBibliografiaNOV 20043IntroduoOrigem Princpio
Sandwich Vantagens e Desvantagens
NOV 20044OrigemII Gerra Mundial de Havilland Mosquito TT35 TA639
Fuselagem Plywood/Balsa/PlywoodMosquito. The timber terror. Light,
fast, deadly.
The excellent performance demonstrated by this airplane had
convinced numerous aircraft designers of the superiority of
sandwich structure as a means of constructing more efficient
airplanes
Falta de materiais na G.B. no auge na II Guerra Mundial
NOV 20045OrigemII Guerra Mundial Vultee BT15 (USA)Fuselagem
Fibra de vidro em matriz de poliester com ncleo em honeycomb de
fibra de vidro ou ncleo de balsa.
NOV 20046Princpio Sandwich
(c) web core(d) corrugated core
NOV 20047Vantagens e desvantagensVantagensDesvantagensAlta
Resistncia EspecficaPerigoso para a sade durante a construo
(Resinas)Alta Rigidez EspecficaFracas possibilidades de reciclagem
(compsitos)Baixo PesoFalta de informao nos engenheiros e designers
Isolamento Trmico e AcsticoProblemas de temperaturaCapacidade de
resistncia corrosoMudana de mentalidades Facilidade de formas
completasControlo de Qualidade Capacidade de absoro de
EnergiaVariedade de critrios de roturaPoucas peas estruturais
necessriasIncompatibilidade de materiais Mltiplas possibilidades de
escolha de materiaisLeis ConstitutivasNOV 20049Leis
ConstitutivasTeoria clssica vs Teoria 1 ordemCampo de
deslocamentosCampo de deformaesRelao Tenso-Extenso TCLLeis
Constitutivas TCLRelao Tenso-Extenso 1 ordemLeis Constitutivas 1
ordemNOV 200410Teoria clssica vs Teoria 1 ordem
Teoria Clssica LaminadosTeoria 1 ordem
NOV 200411Campo de Deslocamentos
Teoria ClssicaLaminadosTeoria 1 ordem
NOV 200412Campo de DeformaesTeoria Clssica LaminadosTeoria 1
ordem
NOV 200413Relao Tenso-Extenso TCL
Teoria Clssica Laminados
Extenses superfcie mdiaCurvaturasRelao Tenso/ExtensoNOV
200414Leis Constitutivas TCL
Foras de membrana actuantes no laminadoMomentos actuantes no
laminadoNOV 200415Relao Tenso-Extenso 1 ordem
Extenses superfcie mdiaCurvaturasRelao Tenso/ExtensoNOV
200416Leis constitutivas 1 Ordem
NOV 200417Exemplo Ensaios 3PB
Viga de contraplacadoComparao entre a TCL e 1 OrdemVigas
sandwich faces em GRP ncleo PU Comparao entre a TCL e 1 Ordem
NOV 200418Exemplo Ensaios 3PBDeslocamento a meio vo:
TCL (bending)
Corte1 OrdemNOV 200419Viga de contraplacado 18.2 mmContraplacado
de madeira de vidoeiro 13 camadas [0,90,0...,0,90,0]Material
OrtotrpicoVo 1000 mmResultados Fora vs Deslocamento
NOV 200420Viga de contraplacado 18.2 mm
NOV 200421Viga sandwich em GRP + PU Viga sandwich Faces em fibra
de vidro em matriz de polisterEspessura de 2.5 mm Gramagem de 900
g/m2Ncleo em espuma de poliuretanoEspessura de 50 mmDensidade de 40
kg/m3
Materiais IsotrpicosFacesE = 6100 MPa = 0.33NcleoE = 7.5 Mpa =
0.33NOV 200422Vigas sandwich em GRP + PU
Design proceduresNOV 200424Design proceduresVrios envelopes de
rotura concorrentesAltamente dependente da geometria e do
carregamento
NOV 200425Design procedures
NOV 200426Design procedures
NOV 200427Design procedures
AplicaesNOV
200429AplicaesAeroespacialAeronuticoConstruoDesportoNavalAutomvel
Veculos FerroviriosetcNOV 200430Satlites
1 Solar Panels : Epoxy carbon prepregs, aluminum honeycomb, film
adhesive 2 Reflectors Antennae : Epoxy/aramid prepreg, cyanate
carbon prepreg, aramid/aluminum honeycomb 3 Satellite Structures :
Carbon prepreg, aluminum honeycomb, film adhesive NOV
200431Aeroespacial1 Fairings: Carbon prepregs. Aluminium honeycomb
and adhesives. 2 External Payload Carrier Assembly (SPELTRA):
Carbon prepregs, aluminium honeycombs and adhesives. 3 EPS Ring:
Epoxy/carbon prepreg or RTM. 4 Front Skirt: Carbon prepreg. 5
Booster Capotage: Epoxy glass/non-metallic honeycomb. 6 Yoke: Epoxy
carbon filament winding. 7 Heat Shield: Carbon prepreg/high
temperature resistant glass fabric.
NOV 200432Aeronautico
1 Radar Transparent Radome: Epoxy or BMI Prepreg or RTM resins
and woven preforms (socks) 6 Wing Skins and Ribs: Epoxy carbon and
glass Prepregs 2 Foreplane Canard Wings: Epoxy carbon Prepregs 7
Fin Tip: Epoxy/quartz Prepregs 3 Fuselage Panel Sections: Epoxy
carbon Prepregs. Non-metallic honeycomb core and Redux adhesives 8
Rudder: Epoxy carbon Prepreg 4 Leading Edge Devices: Epoxy carbon
and glass Prepregs 9 Fin: Epoxy carbon/glass Prepreg 5 Fin
Fairings: Epoxy glass and carbon Prepregs 10 Flying Control
Surfaces: Epoxy carbon and glass Prepregs. Honeycomb core material
and Redux adhesives NOV 200433
Ps do rotor de um helicptero Sea King, mostrando a estrutura
interna em compsito. Com a aplicao de compsitos consegue-se maior
velocidade das ps e menor transmisso de vibraes estrutura.NOV
200434Naval1 Decking: Heavy duty structural sandwich panels 9
Weather Shield: Prepregs and honeycombs. 2 Hull Skin Structure:
Prepregs, engineered fabrics, honeycombs. 10 Communications
Equipment : Prepregs and honeycombs. 3 Lightweight Floor Structure:
Sandwich panels. 11 Companionway Stairs : Structural sandwich
panels 4 Suspended Ceilings : Lightweight sandwich
panels/honeycombs. 12 Partitions: Lightweight sandwich panels. 5
Interior Furnishings : Lightweight stiff sandwich panels suitable
for fabrication. Prepregs and fabrics.13 Lightweight
Superstructure: Sandwich panels and Prepregs. 6 Hull Skin
Structure: Prepregs, engineered fabrics, honeycombs. 14 Engine Room
: Sandwich panels and special products for FST and sound
attenuation.. 7 Accommodation Cabin Units: Lightweight sandwich
panels, Prepregs and honeycombs. 15 Drive Shafts & Couplings:
Epoxy Prepregs and fabrics 8 Bridge Deck Consoles: Lightweight
sandwich panels.
NOV 200435Naval
NOV 200436Desporto
NOV 200437
O quadro (que j nem sequer tem a forma tradicional de um
quadro...) da bicicleta da figura feito em carbono/ epoxy, bem como
as jantes das rodas. Consegue-se maior rigidez e menor peso em
relao s estruturas de alumnio. Alm disso, o design pode e deve ser
alterado para maximizar os benefcios do novo material.NOV
200438
Aplicaes diversas de compsitos em artigos de desporto e lazer. A
sua utilizao destina-se, em geral, a poupar peso, ganhando rigidez
e resistncia e, por vezes, permitindo um design mais atractivo que
as ligas metlicas, devido facilidade de moldagem.NOV 200439Construo
civil
NOV 200440Sandwich technology:The sandwich principle has been
successfully used in the marine and aerospace industries. Now,
Bombardier's new Fully Integrated Carbody Assembly System (FICAS)
revolutionizes manufacturing in the rail industry.
FICAS consists of a thin sandwich construction comprising a
steel skin bonded to a rigid core. The advantage of this approach
to the overall space saving equation is that the sidewalls become
significantly thinner than a conventional wall, with possible
savings of up to 120 millimeters in wall thickness. (May
2003)Comboios
NOV 200441AutomvelWith the long version, the A-class sets a new
record for compact cars, for no other automobile in this market
segment offers so much cubic capacity, as much as 68.2 cubic feet
which is 11 percent more than the unchanged current standard
version.The spatial economy of the new body variant is equally
commendable: since the drive units, thanks to the sandwich concept,
are positioned partly in front of and partly beneath the passenger
cell, 53 percent of the 12 foot 5 inch body is available to the
passengers With the new variant we can now also satisfy prospective
customers who were already convinced by the A-Class design and
concept but wanted to have more room, emphasized D. Joachim
Schmidt, member of divisional management
NOV 200442Automvel
Therefore, American's steel manufacturers hired Porsche
Engineering Services to develop a new kind of steel monocoque
technology calls Ultra Light Steel Auto Body (ULSAB). As shown in
the picture, basically it has the same structure as a conventional
monocoque. What it differs from its donor is in minor details - the
use of "Hydroform" parts, sandwich steel and laser beam welding.
Sandwich steel is made from a thermoplastic (polypropylene) core in
between two very thin steel skins. This combination is up to 50
percent lighter compared with a piece of homogenous steel without a
penalty in performance. Because it shows excellent rigidity, it is
applied in areas that call for high bending stiffness. However, it
cannot be used in everywhere because it needs adhesive bonding or
riveting instead of welding. NOV 200443Transporte Isotrmico
Vantagem da construo sandwich:Alto isolamento trmico aliado ao
desempenho estruturalBibliografiaNOV 200445BibiografiaPlantema,
F.J., Sandwich construction; the bending and buckling of sandwich
beams, plates, and shells. 1966, New York,: Wiley. xx, 246.Allen,
H.G., Analysis and design of structural sandwich panels. 1st ed.
1969, Oxford New York: Pergamon. xvi, 283.Forest Products, L., Wood
handbook : wood as an engineering material. General technical
report (Forest Products Laboratory) ; FPL-GTR-113. 1999, Madison:
The Laboratory.Gay, D., Matriaux composites. 4e d. rev. et augm.
ed. Collection Matriaux. 1997, Paris: Herms,. 672.Gibson Lorna, J.
and F. Ashby Michael, Cellular solids : structure & properties.
International series on materials science & technology. 1988,
Oxford: Pergamon 1988.Metzger, D.J., The selection of sandwich
panels. 1970: Ithaca, N.Y. p. x, 142 l.Middleton, D.H., Composite
materials in aircraft structures. 1990, Harlow: Longman Scientific
& Technical.Vinson, J.R., The behavior of sandwich structures
of isotropic and composite materials. 1999, Lancaster, Pa.:
Technomic Publishing Co.Zenkert, D., An introduction to sandwich
construction. 1997, Warley: Emas.Zenkert, D. and F. Nordic
Industrial, The handbook of sandwich construction. North European
engineering and science conference series. 1997, Cradley Heath:
EMAS Publishing.FIM
