A mechanical model for the computation of phenolic foams in compression

In the field of packaging and cushioning applications, phenolic foams bring a suitable solution because of various qualities: incombustibility, cost, and mechanical behaviour in compression. The present paper is devoted to the development of a mechanical model for those foams, with a view to implementing it into a computer code. The yield criterion is derived from the famous Cam-Clay model provided with a standard flow rule, but the specificity of the model lies in the densification law. The densification equation is defined in an asymptotic form, and is shown to represent accurately the experimental tests in compression. The method of identification is applied to foam samples in a wide range of densities, thus providing a complete characterisation of this family of materials.