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Sasobit has been widely applied as warm-mix asphalt (WMA) additive in an environment friendly and energy saving pavement construction. Epoxy asphalt (EA) has been extensively used on the pavement of steel bridge decks. In the present paper, Sasobit was introduced into warm-mix epoxy asphalt binder (WEAB) to prepare Sasobit modified WEAB. The effect of Sasobit on the viscosity, thermal, damping and mechanical properties and morphology of the neat WEAB were investigated using various characterisation techniques. Sasobit significantly lowered the viscosity of the neat WEAB and prolonged the operational lifetime for mixture pavement. Sasobit lowered the glass transition temperature of the neat WEAB. Sasobit slightly decreases the damping properties and thermal stability of the neat WEAB. However, Sasobit increased the tensile strength of the neat WEAB. The crystalline network structures of Sasobit formed in asphalts were clearly observed. The lamellar crystalline structure of Sasobit turned to gel-like structure in curly ribbon shape with an increase of the WMA additive contents. Reaction-induced phase separation occurred in the neat WEAB and Sasobit modified WEABs. No crystalline network structures of Sasobit were observed in the dispersed asphalt phase of the modified WEABs. Sasobit decreased the size of asphalt particles in the continuous epoxy phase. [ABSTRACT FROM AUTHOR]

ABSTRACT Epoxy asphalt (EA) concretes have been widely used in the pavement of orthotropic steel bridge decks. The objective of this study was to figure out the enhanced effects of natural fibrous attapulgite (ATT) as a reinforced nanofiller in ATT/EA nanocomposites through a comparison of the properties of the composites with a series of various nanoclay loadings. The rheological properties, glass transition, thermal stability, mechanical properties, and morphology of the ATT/EA composites were characterized. Furthermore, the low-temperature flexibility of the ATT/EA concretes was investigated. The test results show that the addition of ATT had no significant effect on the rotational viscosity of EA in the initial stage of the curing reaction. In addition, the ATT/EA composites showed better performance than the neat one in thermal stability with a higher glass-transformation temperature. The tensile strength and elongation at break of the ATT/EA composites at a loading of 0.5 wt % ATT were 21 and 22% higher than those of the neat EA. The addition of ATTs also enhanced the low-temperature flexibility of the EA concretes. © 2014 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2015, 132, 41694. [ABSTRACT FROM AUTHOR]

• Thermal shock significantly increases the pull-off strength of the touch-dry BEBC. • The hydrophilic touch-dry BEBC becomes hydrophobic after the thermal shock. • Thermal shock greatly increases the T g of the touch-dry BEBC. • The touch-dry BEBC's tensile strength increases by about 300% after the thermal shock. • Thermal shock temperature has a limited effect on the mechanical properties of BEBCs. B-staged epoxy bond coat (BEBC) has been widely applied as a waterproof adhesive layer in the pavements of orthotropic steel bridges. During its application, the uncured BEBC layer was first paved on the surface of the steel deck or the bituminous surfacing and hot bituminous mixture would be constructed until the BEBC layer became touch-dry. In this paper, the impacts of thermal shock on the degree of cure (DOC), pull-off strength, hydrophilicity, glass transition temperature (T g), damping performance, thermal stability and mechanical behaviors of the touch-dry BEBC were investigated. Thermal shock greatly increased the DOC of the touch-dry BEBC and the touch-dry BEBC turned to be nearly fully cured after the thermal shock at a higher temperature. The pull-off strength of the touch-dry BEBC was remarkably improved by the thermal shock. After the thermal shock at 160 °C, the pull-off strengths at room temperature and at 60 °C of the touch-dry BEBC were increased by 584% and 914%, respectively. After the thermal shock, the contact angle of the touch-dry BEBC was greatly increased and the hydrophilicity of the touch-dry BEBC was converted to hydrophobicity. Thermal shock significantly increased the T g of the touch-dry BEBC. Furthermore, the T g of thermally shocked BEBCs slightly increased in the temperature. Thermal shock improved the damping performance of the fully cured BEBC. The tensile strength and toughness of the touch-dry BEBC were greatly improved by the thermal shock. However, thermal shock lowered the elongation at break of touch-dry BEBC. In the case of thermally shocked BEBCs, the temperature had a limited effect on the tensile strength, while the elongation at break increased in the temperature. The fracture energy first decreased in the temperature and increased after 150 °C. Maximum fracture energy appeared at 160 °C. After the thermal shock, the tensile strength of the touch-dry BEBC was increased by as much as 3-fold. The fracture energy of the BEBC thermally shocked at 160 °C was 182% greater than that of the touch-dry BEBC. [ABSTRACT FROM AUTHOR]

Epoxy asphalt adhesive (EAA) is a thermosetting polymer modified asphalt that has been widely applied on steel bridge decks as a strong adhesive and waterproof layers. In this study, the influence of the asphalt penetration grade on the viscosity, damping and mechanical properties, bond strength, and microstructures of EAAs was investigated. The viscosity of the EAAs increased with increasing asphalt penetration grade. The presence of base asphalt increased the glass‐transition temperature (Tg) of the neat epoxy. The asphalt penetration grade had a negligible effect on the Tg values of the EAAs. The existence of base asphalt improved the damping behaviors of the neat epoxy. Moreover, the damping properties of the EAAs increased with increasing asphalt penetration grade. The tensile strength, elongation at break, and bond strength values of the EAAs increased with increasing asphalt penetration grade. The bond strengths of the EAAs were 7‐ to 10‐fold higher than that of the neat asphalt. The asphalt penetration grade had a negligible effect on the bond strengths of the EAAs. Morphological observations revealed that the average size of the dispersed asphalt particles in the epoxy decreased with increasing asphalt penetration grade. A more homogeneous phase separation was formed in the EAA with a higher penetration‐grade asphalt. © 2018 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2019, 136, 47027. [ABSTRACT FROM AUTHOR]