Experimental and analytical studies of bacterial self-healing concrete subjected to alkali-silica-reaction

In this study, expansion progresses and mechanical properties after expansion of self-healing concrete subjected to Alkali-Silica Reaction (ASR), one of the most severe damages that concrete structures may experience during their service life, are investigated. To this end, nine bio-based self-healing mortar bars of 40 × 40 × 160 mm dimensions and three concrete prisms of 75 × 75 × 285 mm dimensions containing different percentages of reactive aggregate and healing agents as well as different reactive aggregate sizes were manufactured. The samples were subjected to accelerated ASR tests, in which changes in length and weight were measured periodically. Flexural and compressive tests were also carried out. Moreover, microstructural features of the specimens were evaluated by Scanning-Electron-Microscopy (SEM). An analytical study was conducted to develop a model for predicting ASR-induced expansion in self-healing concrete. Based on the results, self-healing concrete could not recover from ASR damage. The expansion and mechanical properties of ASR-affected self-healing concrete increased and decreased, respectively.