Print Email Facebook Twitter Optimization of the calcium alginate capsules for self-healing asphalt Title Optimization of the calcium alginate capsules for self-healing asphalt Author Xu, S. (TU Delft Materials and Environment) Tabakovic, A. (TU Delft Materials and Environment; University College Dublin; Technological University Dublin) Liu, X. (TU Delft Pavement Engineering) Palin, D. (TU Delft Materials and Environment; Cornell University) Schlangen, E. (TU Delft Materials and Environment) Date 2019 Abstract It has been demonstrated that calcium alginate capsules can be used as an asphalt healing system by pre-placing rejuvenator (healing agent) into the asphalt mix and releasing the rejuvenator on demand (upon cracking). This healing mechanism relies on the properties of capsules which are determined by the capsule preparation process. In this study, to optimize the calcium alginate capsules, capsules are prepared using varying Alginate/Rejuvenator (A/R) ratios. Light microscope microscopy and Environmental Scanning Electron Microscope (ESEM) are employed to characterize the morphology and microstructure of these capsules. Thermal stability and mechanical property are investigated by thermogravimetric analysis (TGA) and compressive tests. The testing results indicate that higher alginate content results in smaller diameter and lower thermal resistance, but higher compressive strength. The optimum A/R ratio of calcium alginate capsules is found to be 30/70. To prove the effectiveness of the optimized capsules, the capsules are embedded in asphalt mortar beams and a bending and healing program is carried out. The effect of capsule shell material on the mechanical response of asphalt mixture is evaluated through three-point bending on the mortar beams embedded with blank capsules (without the healing agent). Aged mortar beams containing alginate capsules encapsulating rejuvenator demonstrate a higher strength recovery after bending tests, which indicates effective healing due to the release of the rejuvenators from the capsules. Subject AlginateAsphaltCapsulesRejuvenation To reference this document use: http://resolver.tudelft.nl/uuid:cb52ff20-8113-430d-a659-3b45c61233b1 DOI https://doi.org/10.3390/app9030468 Source Applied Sciences, 9 (3) Part of collection Institutional Repository Document type journal article Rights © 2019 S. Xu, A. Tabakovic, X. Liu, D. Palin, E. Schlangen Files PDF applsci_09_00468_v2.pdf 2.95 MB Close viewer /islandora/object/uuid:cb52ff20-8113-430d-a659-3b45c61233b1/datastream/OBJ/view