Design and Analysis of Composite Structures: With Applications to Aerospace Structures, 2nd Edition

12

Good Design Practices and Design ‘Rules of Thumb’

Throughout the previous chapters, several guidelines that result in robust designs have been presented and, in some cases, analytical models that support them were given. In this chapter, all the rules already mentioned in this book are collected and some new ones added to provide a framework within which most composite designs can perform successfully.

Design guidelines are a result of analysis and trending, test results and experience. As such, they typically have a range of applicability (especially in terms of the stacking sequences to which they apply) outside of which they may or may not be as successful. There is no reason why any and all of the guidelines should be closely followed. Deviations and departures from them are often necessary. As long as the reasons for deviation are understood and test results and accurate analysis are available to support that deviation, there is no reason to limit the designs by following these guidelines. In fact, there is a motivation to open up or reformulate some of these guidelines in order to generate more efficient and/or more robust designs in the future [1].

The most important guidelines with a brief discussion are listed below. Other guidelines and/or variations of the ones presented below can be found in the literature, for example, in reference [2].

12.1 Layup/Stacking Sequence-Related

1. The layup (stacking sequence) of a laminate should be symmetric. This eliminates unwanted ...