Nezbedova, Vlach, Knesl
# 2006 Washington DC
A multilayer pipe consisting of two different layers, namely of PE and PPH, was analysed. The relevant numerical model based on the Finite Element Method (FEM) was used to calculate the stress and strain distribution and to estimate the fracture characteristics. As variables the thickness of the material layers and their elastic modulus were chosen. From the experimental point of view the C type specimens taken from the pipes were tested under the static load and the fracture characteristics (R-curves and fracture toughness) were estimated. A good correlation between the theoretical and experimental results was obtained. The agreement provides the possibility of simulating a different combination of materials and geometry of the layers with the aim of achieving the optimal resistance to stable crack growth.
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