ABSTRACT
Various temperature shift factor approaches are used to account for time-temperature equivalencies while constructing master curves. Even with good quality control measures, significant scatter in dynamic shear modulus (|G*|), phase angle (ɸ) data is observed. This, in turn, results in uncertainty in finalized relaxation modulus, G(t) and creep compliance, J(t) master curves when interconversion techniques are used. This uncertainty could be ascribed to factors like material testing practices, human errors, experimental errors, numerical approximations etc. This study presents a comprehensive approach to evaluate the uncertainty that is propagated to J(t) and G(t) values during master curve construction and interconversion process. Two shift factor construction methods, i.e, asymmetric Kaelble shift factor method and symmetric free shifting approach are considered during the master curve construction process. The uncertainty parameters such as Normalised Uncertainty Range (NUR) indicated that asymmetric-Kaelble method results in lower uncertainty when compared to symmetric-free shifting approach.
