GAO Zhihao (1992-), male, Doctoral candidate. E-mail: 78775790@qq.com
The effect of restraint (i.e., expansion restraint and shrinkage restraint) on the surface damage of single-side salt freezing and thawing (SSFT) of concrete and its mechanism were investigated. After every four SSFT cycles and the strain during the cooling phase of the first SSFT cycle, the surface scaling was measured on the restrained concrete with a water-cement ratio of 0.40, and the tensile stress in the ice on the concrete surface was calculated. The results show that the surface scaling of restrained concrete is greater than that of free concrete, and it increases with the increase of the expansion restraint stress, but has little relationship with the shrinkage restraint stress. Compared to the free concrete, the tensile stress in the ice on the restrained concrete's surface is greater, and it is influenced by the expansion restraint stress positively. The results calculated based on the theory of "glue-spall" indicate that the expansion restrains cause the ice to crack more easily and more serious surface damage to concrete under the ice.
| 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 |