This study has been investigated the effect of freeze-thaw cycles and aging condition on the pure mode I, pure mode II and mixed-mode I/II fracture resistance of Cement Emulsified Asphalt Mortar (CEAM). The experiments were conducted on SCB specimens designed with 16 randomized mix designs with different cement contents (C), asphalt-to-cement ratios (A/C), and water-to-cement ratios (W/C) using the D-optimal response surface methodology. The specimens were divided into three groups: control specimens (n=144), aged specimens (n=144), and specimens subjected to 1, 3, 5, and 10 freeze-thaw cycles (n=576). The experiments were performed in three modes of loading: pure tensile (I), pure shear (II), and mixed-mode tensile-shear (I/II). To assess the impact of freeze-thaw and aging damage on fracture properties, the Fracture Energy Ratio (FER) was defined as the ratio of fracture energy of the damaged/conditioned specimen to that of the corresponding control specimen. Then, a number of statistical models were developed for the relationship between FER and mix design variables (A/C, W/C, and C). The results showed that the application of freeze-thaw cycles reduced the fracture energy of CEAM in all three modes. The independent variable with the greatest impact on fracture energy changes was A/C for the pure tensile mode, and C for the pure shear mode and the mixed-mode tensile-shear. The initial freeze-thaw cycles were found to have a greater impact on fracture energy than later cycles. Also, freeze-thaw cycles are more detrimental in reducing mode II fracture energy than mode I and mixed-mode I/II fracture energies and therefore have a more damaging impact on the pure shear fracture properties of CEAM. Aging also reduced the fracture energy of CEAM in all three modes; an effect that was most greatly influenced by the amount of asphalt in the mortar composition. Aging had a greater impact on mode I fracture energy than mode II and mixed-mode I/II fracture energies.

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