Abstract
It has become one of the research directions of intelligent materials for self-healing asphalt pavements to use a bionic microvascular containing oily rejuvenator. The rejuvenator in a microvascular can carry out the healing of asphalt micro-cracks, thus reducing the damage to and prolonging the life of asphalt pavement. The aim of this work was to investigate the smart self-healing capability of an asphalt/microvascular material through its microstructure and mechanical properties. Microstructure observation indicated no interface separation between the microvasculars and bitumen matrix. Micro-CT images showed that microvasculars dispersed in asphalt samples without accumulation or tangles. The phenomenon of microcracks healing without intervention was observed, which proved that the fractured asphalt sample carried out the self-healing process with the help of rejuvenator diffusing out from the broken microvasculars. The self-healing efficiency of asphalt samples was also evaluated through a tensile test considering the factors of microvasculars content, healing time and healing temperature. It was found that the tensile strength of the asphalt samples was greatly enhanced by the addition of microvasculars under a set test condition. Self-healing efficiency was enhanced with more broken microvasculars in the rupture interface of the asphalt sample. During two self-healing cycles, the self-healing efficiency of the asphalt sample with three microvascular per 1 cm2 of a broken interface were able to reach 80% and 86%. This proves that microvasculars containing rejuvenator play a practical role in the self-healing process of asphalt. With an increase in temperature from 0 to 30 °C, the self-healing capability of the asphalt samples increased dramatically. An increase in time increased the self-healing capability of the bitumen samples. At last, a preliminary mathematical model also deduced that the self-healing efficiency was determined by the individual healing steps, including release, penetration and diffusion of the rejuvenator agent.
Highlights
It has become one of the research directions of intelligent materials for self-healing asphalt pavements to use a bionic microvascular containing oily rejuvenator
The self-healing concept has been introduced into the field of asphalt pavement materials
The self-healing capability of asphalt/microvascular material had been investigated through the microstructure and its mechanical properties
Summary
It has become one of the research directions of intelligent materials for self-healing asphalt pavements to use a bionic microvascular containing oily rejuvenator. During two self-healing cycles, the self-healing efficiency of the asphalt sample with three microvascular per 1 cm of a broken interface were able to reach 80% and 86%. Asphalt owns a self-healing capability due to the viscoelasticity of bituminous material [2] This inherent self-healing capability will be destroyed as service-time goes on. Much research has been carried out to extend the service life of asphalt pavement and enhance the self-healing capability of asphalt with the assistance of smart materials [4]. These methods include polymer blending, nano modification, electrothermal conversion and rejuvenator application [5]. As an intelligent engineering material, this microcapsule powder has been successfully applied in China as a commercial product [10]
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
