ABSTRACT
Wall thickness of fiber reinforced plastic vessels, tanks and piping usually consists of a combination of many layers. This combination can include a liner (veil or thermoplastic) and a hand-lay-up layer (mat and woven roving or just mat alone). Another combination can be a liner plus a thin layer of mat and the structural part is made of filament-wound layers. In order to study the deformation behavior of the structure and to calculate the stresses and strains in the different layers, it is important to be able to treat the layers as a group and also as individual layers. Laminate theory is a powerful technique that allows one to do that.
