Cracking in concrete structures has always been a concern for researchers, designers and constructors. In hydraulic and hydropower engineering, structures such as concrete dams and the linings of water conveyance tunnels often operate under water pressure, and cracking is to some extent inevitable. However, most cracked concrete structures are still able to function safely. This raises questions about whether cracks can be permitted in concrete structures, what size cracks will not cause failure, and what reasonable criteria should be used to describe and evaluate the extent of concrete cracking. In this paper a method is proposed for establishing the cracking criteria of hydraulic concrete based on the anti-seepage function, which can be used for the cracking analysis of hydraulic concrete structures with water-retaining faces. First, the anti-seepage requirements of hydraulic concrete are determined in accordance with relevant codes and actual engineering practices. Then, experimental studies are conducted to establish the relationship between the uniaxial tensile strain and both the permeability coefficient and crack width of concrete. Subsequently, numerical simulations are employed to derive the correlation between the uniaxial tensile strain and the equivalent plastic strain, which is further validated for its applicability under complex stress states in hydraulic structures. Accordingly, thresholds for equivalent plastic strain and crack width, based on the anti-seepage function, are then proposed as the cracking criteria for hydraulic concrete structures. The research of this paper provides new criteria for the cracking analysis of hydraulic concrete which promise good practical application value.
| 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 |