Composite materials are nowadays involved in various designs [1] in areas like aeronautics, road, rail or sea transportation, and chemical industries, among other. Using these material brings a number of advantages: the lowering of overall mass, the increase in the applied mechanical loads before breakdown occurs, the resistance to contamination by chemical agents, the ease of material forming using molding techniques, and the matchability of the material to the particular mechanical function required for a given part in a structure. Among composite materials, the carbon-epoxy ones are costly but also very efficient. They find important applications in aeronautics and we will focus our attention here to them.