40207_12 - SANDWICH CONSTRUCTION Andrew C . Marshall 12...

Info iconThis preview shows pages 1–3. Sign up to view the full content.

View Full Document Right Arrow Icon
SANDWICH CONSTRUCTION 12 Andrew C. Marshall 12.1 INTRODUCTION This chapter covers a unique form of com- posites known as ’structural sandwich construction’. A structural sandwich consists of three ele- ments, as shown in Fig. 12.1: I Fig. The elements of a sandwich structure are as follows: (a) two rigid, thin, high strength facings; (b) one thick, low density core; and (c) an adhesive attachment which forces the core and facings to act as a continuous structure. The facings of a sandwich panel act similarly to the flanges of an I-beam, resisting the bending loads and increasing the bending stiffness of the structure by spreading the facings apart. However, unlike the I-beam’s web, the core gives continuous support to the flanges or facings. Handbook of Composites. Edited by S.T. Peters. Published in 1998 by Chapman & Hall, London. ISBN 0 412 54020 7 1. a pair of thin, strong facings; 2. a thick, lightweight core to separate the fac- ings and carry loads from one facing to the other; and 3. an attachment which is capable of transmit- ting shear and axial loads to and from the core. This chapter provides a general background and a brief summary of the various materials in common use; the design steps used to cal- culate loads; some design details for solving load point, edging and attachment problems; and a few tables, charts and graphs containing useful information for the designer. An attempt is also made throughout the chapter to provide suggestions and perspectives to help a new user of sandwich structures tech- nology to avoid some of the errors of his predecessors. Structural sandwich construction is one of the first forms of composite structures to have attained broad acceptance and usage. Virtually all commercial airliners and helicopters and nearly all military air and space vehicles make extensive usage of sandwich construction. In recent years, most commercial space vehicles have also adopted this technology for many components. The effectiveness of sandwich construction is shown in Fig. 12.2. In addition to air and space vehicles, the sys- tem is commonly used in the manufacture of cargo containers, relocatable shelters and air- field surfacing, navy ship interiors, small boats and yachts, duplicate die models and produc- tion parts in the automobile and recreational
Background image of page 1

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full DocumentRight Arrow Icon
Fncing material 255 Fig. 12.2 A striking example of how conversion to sandwich stiffens a structure without materially increas- ing its weight. This example uses 1.6 mm (0.063 in) thick aluminum facings and 1/4-5052 37 kg/m7 (2.3 lb/fPj aluminum core. vehicle industry, snow skis, display cases, resi- dential construction materials, interior partitions, doors, cabinets and a great many other everyday items. Although the employment of sandwich design to produce lightweight or special pur- pose load-carrying members is thought to have originated as early as 1820, routine com- mercial use of the idea did not occur until about 110 years later. What started this sudden acceptance was the successful commercial pro- duction of structural adhesives, starting in both UK and USA in the 1920s and 1930s.
Background image of page 2
Image of page 3
This is the end of the preview. Sign up to access the rest of the document.

Page1 / 37

40207_12 - SANDWICH CONSTRUCTION Andrew C . Marshall 12...

This preview shows document pages 1 - 3. Sign up to view the full document.

View Full Document Right Arrow Icon
Ask a homework question - tutors are online