Hygrothermal Stresses Analysis of Thick Composite Plates Using High Order Theory Under a Fick Concentration Distribution

Abstract

Composite materials are very important and have a wide use in various fields. In aeronautics these materials represent a great potential due to their rigidity and lightness. Aeronautical structures work in variable environmental conditions because of the change in altitude during a flight. Consequently, the temperature and the humidity vary, and these parameters generate internal stresses which influence the behaviour of the material. So, the determination of hygrothermal stresses is very important.This study investigates the behaviour of thick composite laminates using a high order method through hydrothermal stress calculation. Composite laminate working in a symmetric hygrothermal environment, temperature and humidity are used and taken into account for stress calculation. The moisture distribution is calculated along the thickness of the laminate using the Fick equation. Different numerical simulations are carried out using different values of temperature and humidity rate to see their influence. Other simulations were made by varying the distribution of temperature along the thickness of the laminate; the plate size is also taken into account in the simulations (a/b: ratio of length to width, a/h: ratio length to thickness).