Assessment of fracture properties of emulsified asphalt mixtures

This paper presents an investigation into factors affecting the fracture properties of a cold-laid material used as base or binder course on medium to lightly trafficked roads. The Semi-Circular Bending beam test has been used to study the effect of temperature and rate of loading on the fracture properties, expressed as fracture toughness and fracture energy, of the cold-laid material in mode I. A Hot Mix Equivalent mixture was used in the study comprising the same aggregates and base binder. An immersion regime adopting vacuum moisture saturation was undertaken to assess the effect of ingested moisture on the measured fracture properties. At-10 and -20°C, the fracture toughness of the cold material was almost independent of temperature. At - 20°C, the fracture energy of the cold and hot materials were almost equal irrespective of loading rate. The cold mixture attained reasonably high retained fracture toughness upon vacuum moisture saturation.