Self-healing of glass fibre reinforced concrete (GRC) and polymer glass fibre reinforced concrete (PGRC) using crystalline admixtures

Influence of Crystalline Admixtures and Their Synergetic Combinations with Other Constituents on Autonomous Healing in Cracked Concrete—A Review

“…Commercial CA is usually made of ordinary Portland cement, quartz sand, and other active substances. A significant number of microstructural investigations such as XRF [9,10,15,[36][37][38][39], XRD [37,38,40], SEM [39,41,42], EDS [42], FTIR [40], and particle size distribution test [37,38] have been conducted to characterize the elemental composition of the commercial CAs. Major conclusions are as follows:…”

“…(1) The test results of XRF shown in [40] investigated five brands of CA (specific brands were not mentioned). The FTIR and XRD patterns of CA-A and CA-D were similar, but the healing effect differed.…”

“…Permeation (water leaking through cracks) [7,15,31,38,56] Water immersion [5,6,9,10,28,29,36,40,42,44,46,[48][49][50][51]54] Wet-dry cycles [28,36,39,51,52] Standard curing [6,44,58] Climate chamber/humidity chamber [42,45,49] Water contact [49,56] Air exposure [28,31,36,42,44,48,49] Steam curing (80 • C) [41] Water immersion (synthetic sea water) [4,55] Geothermal water immersion [45,47] Wet-dry cycles (0.545 mol/L and 2 mol/L chloride solution) [39] Wet-dry cycles (geothermal water) [45,47]…”

“…Steel fibers [28,42,44,[47][48][49]51] Polyvinyl alcohol (PVA) fibers [5,36,39] Glass fibers [40] Amorphous fibers [47] Cellulose nanocrystals, cellulose nanofibrils [45] Alumina nanofibers [45,53] Cuenca et al [28] studied the effect of steel fiber arrangement direction on the healing of CA specimens. It was found that the average crack closure rate (77.83%) of specimens with parallel fibers was significantly higher than that of specimens with vertical fibers (54.70%).…”

“…It was found that the average crack closure rate (77.83%) of specimens with parallel fibers was significantly higher than that of specimens with vertical fibers (54.70%). Guzlena et al [40] added acrylic polymers and glass fibers to produce specimens with higher bending strength to prevent the specimen from damage. It was found that the film formed by acrylic polymers could prevent the crystal from contacting water.…”