【Daily Discussion】Public Utilities – Water Resources and Hydropower – 20210509

The main methods of discharging water through the body of an arch dam include free fall, flip bucket type, ski-jump type, and spillway orifices in the dam body.      Free-fall type: Suitable for hyperbolic arch dams or small arch dams with good bedrock, low discharge rates, and thin dam bodies.     Nose weir type: Suitable for situations where the dam is high and the flow per unit width is large.     Slope type: Suitable for arch dam complexes with large flood discharge volumes and thin dam bodies.     Spillway-type for the dam body: suitable for tall hyperbolic thin-arch dams.

The flood discharge methods for arch dams include crest overflow and spillways in the dam body. 　 　Spillway types at the dam crest include: ① Free-fall type, characteristic: suitable for situations with good bedrock and low discharge rates ； Simple structure, easy to construct ； The water jet ventilation conditions are poor, so flow separation cannot occur ； Slope-following flow is likely to occur. 　 　②The nose weir type features a reverse-curved nose weir connected to the curved dam crest, which helps reduce the vibration of the overflow flow and prevents flow along the slope at low head levels ； It facilitates flow separation. 　 　③Slope-type: characterized by a large height difference and long span, ranging from 60 to 100 meters; it has a complex structure and requires substantial construction efforts. It is suitable for arch dams with high discharge capacities and thin profiles. 　 　The spillway holes in the dam body can be used to empty the reservoir, allowing for the early release of floodwater

The flood discharge methods for arch dams include crest overflow and spillways in the dam body. 　 　Spillway types at the dam crest include: ① Free-fall type, characteristic: suitable for situations with good bedrock and low discharge rates ； Simple structure, easy to construct ； The water jet ventilation conditions are poor, so flow separation cannot occur ； Slope-following flow is likely to occur. 　 　②The nose weir type features a reverse-curved nose weir connected to the curved dam crest, which helps reduce the vibration of the overflow flow and prevents flow along the slope at low head levels ； It facilitates flow separation. 　 　③Slope-type: characterized by a large height difference and long span, ranging from 60 to 100 meters; it has a complex structure and requires substantial construction efforts. It is suitable for arch dams with high discharge capacities and thin profiles. 　 　The spillway holes in the dam body can be used to empty the reservoir, allowing for the early release of floodwater

The main methods of discharging water through the body of an arch dam include free fall, flip bucket type, ski-jump type, and spillway orifices in the dam body. Free-fall type: Suitable for hyperbolic arch dams or small arch dams with good bedrock, low discharge rates, and thin dam bodies.

The flood discharge methods for arch dams include crest overflow and spillways in the dam body. 　 　Spillway types at the dam crest include: ① Free-fall type, characteristic: suitable for situations with good bedrock and low discharge rates ； Simple structure, easy to construct ； The water jet ventilation conditions are poor, so flow separation cannot occur ； Slope-following flow is likely to occur. 　 　②The nose weir type features a reverse-curved nose weir connected to the curved dam crest, which helps reduce the vibration of the overflow flow and prevents flow along the slope at low head levels ； It facilitates flow separation.

③Slope-type: characterized by a large height difference and long span, ranging from 60 to 100 meters; it has a complex structure and requires substantial construction efforts. It is suitable for arch dams with high discharge capacities and thin profiles.

The main methods of discharging water through the body of an arch dam include free fall, flip bucket type, ski-jump type, and spillway orifices in the dam body. Free-fall type: Suitable for hyperbolic arch dams or small arch dams with good bedrock, low discharge rates, and relatively thin dam bodies. Nose weir type: Suitable for situations where the dam is relatively high and the flow per unit width is large ； Slope type: Suitable for arch dam complexes with large flood discharge volumes and thin dam bodies ； Spillway-type for the dam body: Suitable for double-curved thin arch dams with high heights.

Briefly describe the methods of water discharge from the body of an arch dam and its applicable conditions.