YU Jianwei (1997-), male, Master candidate. E-mail: 498503906@qq.com
Influence of silane emulsion hydrophobic agent as an additive on the strength and capillary water absorption behavior of concrete was investigated through strength test, hydration heat test, thermogravimetric analysis, capillary water absorption and mercury intrusion test. The results show that silane emulsion reduces the early-age compressive strength and splitting strength of concrete, which is mainly attributed to the retardation effect of silane emulsion on the early cement hydration. The capillary pore volume in 28-d harden cement paste is increased by adding silane emulsion because of the depressed cement hydration. However, the initial water absorption rate, the secondary water absorption rate and the total amount of water absorption of the 28-d concrete during capillary water absorption process are greatly reduced by silane agent. This is since silane emulsion reacts with cement hydration products to form an alkyl hydrophobic layer on the pore wall of the capillary pores, which changes the surface property of the wall from hydrophilic to hydrophobic, thus significantly reducing the rate and the amount of water absorption of concrete. Silane agent has a more profound influence on the concrete properties with a higher water-cement ratio due to the lager capillary pore volume.
| 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 |