Spore 1.6 ((INSTALL)) Crack
Spore 1.6 ((INSTALL)) Crack
Spore 1.6 Crack
Ideally, the surrounding environment should be conducive to the growth of bacteria and influence the rate of healing. Chemical self-healing agents such as sodium chlorite [ 23 ] and calcium hypochlorite [ 24 ] have been suggested for use as preventive measures for crack formation. However, these approaches may not be cost-effective and could lead to additional environmental pollution. Instead, using bacteria to promote self-healing may be a more sustainable method to address this situation. Walsh and Murray [ 25 ] explored the feasibility of using geobionts (microorganisms that live naturally in, on or near concrete) as agents that can contribute to the self-healing process. They defined the geobionts as microorganisms that: (a) exist naturally in, on or near concrete; (b) do not require a living host; and (c) are relatively easy to culture under laboratory conditions. They confirmed that concrete can support the growth of some types of geobionts, especially fungi. Bacteria have also been shown to facilitate the growth of fungi and vice versa. This mutualism is an important key to understanding the self-healing process. For example, in the current study, micromycetes were shown to colonise in the cracks of the wet-dry cycle specimens within 6h of incubation. These include species that can promote the self-healing of cracked concrete (such as Trichoderma ovatum and Rhodocollybia aurantia), create the micro environment that allows fungus to grow (such as Geomyces spp.) and/or protect fungi against damage (such as Mortierella corymbifera) [ 25, 31, 32, 33, 34 ].
furthermore, capillary water absorption, capillary suction and chloride diffusion tests were conducted to investigate the potential of concrete self-healing materials to undergo chemical changes. the capillary suction test is linked to the tightness of the crack and a higher rate of water uptake indicates greater tightness. the results showed that the water absorption rate in the capillary suction of the oven-dried mortar specimens was higher (0.0027 and 0.0060cm/s) compared to the specimens immersed in water. this finding is consistent with previous studies [ 45 ] that reported that the dry mortar specimens exhibited higher capillary suction coefficient values than those immersed in water. therefore, water absorption by the oven-dried mortar specimens was greater than the specimens immersed in water, therefore, the capillary suction of the oven-dried mortar specimens was greater than the specimens immersed in water. furthermore, for the specimens cms and bms immersed in water, a relatively larger reduction in the sorptivity index (8.914106 and 7.242105mm/s, respectively) was observed, which was more compatible with the result obtained in the capillary suction test. therefore, the self-healing of concrete, especially with the addition of eps, appears to be the best for concrete with a high water absorption ratio, which has been reported in previous literature [ 13, 44 ]. in addition, this finding is consistent with the sealing capacity of eps which is, therefore, effective in repairing cracks in concrete [ 18 ].
for the specimens immersed in water, the chloride diffusion coefficient (2.25e-04cm/s) was very low. this low value was expected for the cracked specimens (in water), as water has a low diffusion coefficient in comparison to other fluids, such as salt water, water vapour and carbon dioxide [ 47 ]. however, for the oven-dried concrete specimens, the chloride diffusion coefficient (1.49e-05cm/s) was much higher, which was consistent with the results obtained for the capillary suction test.