Preparation and application of novel microcapsules ruptured by microwave for self-healing concrete

Abstract Self-healing microcapsules show great potential in extending the service life of concrete, but it is a challenge to achieve the smart release of the healing agent from the microcapsules. In this research, Novel Microcapsules Raptured by Microwave (NMRM) with unique core–shell structure for self-healing concrete were successfully produced. The core content was calculated and the surface morphology and size distribution of NMRM were explored by Scanning Electron Microscope (SEM) and Dynamic Light Scattering (DLS). The temperature variations of specimens were monitored by a thermal infrared imager. Furthermore, the effects of NMRM dosage on the fundamental performance of concrete was investigated and self-healing behavior of the mortar and concrete were evaluated. As a result, rapture of microcapsules with 5% graphite can be quickly triggered under the microwave irradiation. The 60% fc0 pre-damaged concrete with 5% NMRM possessed 92.6% of CSRR. The purpose of this investigation is to provide a new trigger for microcapsule rupture on the specific location with cracks at the right time for self-healing concrete.