LEI Dongyi (1986-), male, Ph.D., Associate Professor. E-mail: leidongyi@qut.edu.cn
Cement-based materials have a multi-phase and multi-scale structure, and each component forming the structure affects the overall toughness to varying degrees. This review summarized the cracking-resistance and toughening mechanisms of relevant components classified in macroscale, mesoscale and nanoscale to cement-based materials. In the macroscale (such as the cementitious component, aggregate, admixture, fiber, water-binder ratio, curing system, etc.), the influence mechanisms of the physicochemical effects of relevant components on the cracking resistance and toughening characteristics of cement-based materials were analyzed. In the mesoscale (such as microsphere, whisker, capillary crystalline material, etc.), the enhancement effects such as volcanic ash, filling, bridging, bonding, capillary crystallization were described. In the nanoscale (such as nano-SiO2, nano-CaCO3, graphene, carbon nanotube, microorganism, nano-polymer, etc.), the mechanisms enhancing and optimizing the microstructure of hydration products, growth mode, and pore structure of hardened paste were introduced. The conjugating toughening effects of cross-scale components such as 'carbon fiber+carbon nanotubes', 'fiber+whisker+graphene' were elucidated. In addition, the shortcomings in the current application/research, and the future development trends for toughening components in different scales were also discussed.
| 科 Family | 属数 Number of genus | 种数 Number of species | 占总种数比例 Percentage of total species (%) | 属 Genus | 种数 Number of species | 占总种数比例 Percentage of total species (%) |
|---|---|---|---|---|---|---|
| 鹅膏菌科Amanitaceae | 2 | 11 | 5.26 | 鹅膏菌属 Amanita | 10 | 4.78 |
| 小菇科 Mycenaceae | 2 | 12 | 5.74 | 丝盖伞属 Inocybe | 5 | 2.39 |
| 多孔菌科 Polyporaceae | 8 | 14 | 6.70 | 蜡蘑属 Laccaria | 5 | 2.39 |
| 红菇科 Russulaceae | 3 | 23 | 11.00 | 小皮伞属 Marasmius | 6 | 2.87 |
| 小菇属 Mycena | 11 | 5.26 | ||||
| 光柄菇属 Pluteus | 5 | 2.39 | ||||
| 红菇属 Russula | 17 | 8.13 | ||||
| 栓菌属 Trametes | 5 | 2.39 |