4. Dimensioning composite cylinders

The use of composite materials for underwater enclosures can be divided into three fields of application:

• shallow depth. The dimensioning of the structure is then mainly conditioned by the stability of a component or the complete system (buckling problem);

• depth. Sizing is then governed by the strength of the materials chosen;

• intermediate depth. Both phenomena (buckling and material strength) are then taken into account. One optimization criterion may be the simultaneous occurrence of failure and buckling.

Figure 10 schematically illustrates the two failure modes....