The construction and design of centrifugally cast glass fiber reinforced plastics pipes (CC-GRP pipes) and the nature of the materials used require a methodology that includes: (1) an efficient test concept along with an adequate simulation process for specimen preparation (2) the application of polymer mechanics and physics concepts (3) proper engineering approaches in correlating material property data from laboratory specimens and pipes To describe the stress-strain behavior of the material a bilinear isochronous material law is proposed, derived from monotone tension/compression tests. Combined with normalized property functions effects related to 1. the degree of anisotropy 2. the moisture content 3. the time 4. the temperature and 5. fatigue can be implemented into the proposed material law. Examples were given for the time-dependent E-modulus E_A(t) and the time dependent strength σ_B(t). In order to extend the applicability of the material laws for design and FEA the further working program will focus on multiaxial loading conditions, the interactions of different influencing parameters and on the formulation of adequate failure criteria.
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