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Abstract
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Composite tubes are being vastly used in the oil, gas, and water industries for transferring underground fluids and highly corrosive
liquids. Glass Resin Epoxy (GRE) pipes are adopted as a more economically sound alternative compared to steel tubes due to
their lower corrosion and higher strength, hardness, and fatigue resistance. The widespread use of GRE tubes, has encouraged
researchers to conduct empirical and theoretical researches towards a better understanding of the mechanical properties, failure,
and response of such tubes in diverse loading circumstances. Some GRE pipe material properties, such elasticity moduli, Poisson’s
ratio, and tensile strength are simply and accurately determined by the aid of the standard tensile test. On the other hand, the
reliability of the GRE pipe compression properties derived from compression tests performed on very tiny speciments, is a matter
of serious concern due to the locality and buckling errors. However, extensive compressions are expected during the service
life of burried pipes. In this thesis, the GRE material properties in compression are explored by introducing the ASTM D2412
flexural stiffness test force-displacement results to an inverse analysis approach. To this end, the flexural stiffness test setup for
an 8-layer, 2.5mm thick GRE pipe with a diameter of 200mm and diverse filament winding angles of 45°, 55°, and 65°, has
been numerically simulated in ABAQUS. The Hashin material model has been attributed to the pipe material and by defining a
proper discrepancy function, a set of sensitivity analyzes has been performed to assess adequate sensitivity of the test measurable
quantities to the sought parameters. The discrepancy function has been minimized through an interaction constructed between
Mathlab, Phython, and ABAQUS environments, and in order to verify the proposed method, an analytic response relevant to a
priori known set of material parameters, has fed to the constructed algorithm as pseudo-experime
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