SU109244A1 - Application for determining the flow of water on mountain rivers, carrying into the pavolk a significant amount of suspended and drawn sediment, a spill gauge - Google Patents

Description

The invention relates to overflow measuring devices for determining water flow on mountain rivers, carrying a significant amount of suspended and trailed sediment into the flood.

Reliable measuring devices of this kind are not yet known in the technique.

The use of blade turntables on these rivers, as a rule, is impossible because of the small depths of the flow in low-flow periods and the large sediments drawn into the flood. The blades of the turntables are deformed and broken by these naios.

Chemical and electrochemical methods are complex, expensive and not accurate enough.

The use of conventional dimensional weirs is made difficult by the fact that the approach section, located above the measurement weir, quickly becomes clogged with sediments, as a result of which the conditions of the flow approach to the weir are distorted and there is a need for constant cleaning of this area from sediments.

The proposed measuring device is free from the listed drawbacks. This is achieved by performing it in the form of a control threshold with a horizontal rib, used for spinning measurements of flood water flow, a thin-walled measuring weir with interchangeable drainage shells and a settling basin located between the control threshold and the measuring weir and equipped with inclined washing pipes.

FIG. 1 schematically shows the implementation of the water-measuring device in the plan; in fig. 2 shows a section along AA in FIG. one; in fig. 3 - in section along the BB in FIG. one.

The water metering device according to the invention consists of the following main components: the control threshold / used for spinner measurements of the flood water flow, the thin-walled weir 2, the settling basin 3, equipped with inclined (discharge) flushing pipes 4.

The threshold of the control / s with a horizontal edge is located on the upstream side of the settling basin, which is one of its walls. Perform a threshold control of concrete. A service bridge is located above the threshold of control. Observations above the level on the threshold of control are carried out by rails installed on both banks.

Thin-walled measured weir 2 with interchangeable weir shields is located downstream of the control threshold. The weir is made of sheet steel with a thickness of 5 to 8 mm and is attached to the concrete wall with bolts with a base of steel strips for bolt heads along the entire length of the sides of the weir. An anti-seepage pad is laid between the concrete wall and the weir.

The slop basin 3 is located between the control threshold and the weir 2.

The cross-section of the basin is chosen so that the water velocity, even with partial sedimentation, is no more than 0.20-0.25 lisek.

The floor of the basin has a double slope: one longitudinal over the entire length of the basin, the mud of the basin and the weir, and the second cross to the side walls, near which the drain pipes 4 are located. Drainage pipes are laid on the sides of the lower wall of the pool. The upper edge of them is located at the level of the bottom of the pool at the junction of pipes or slightly lower. Downpipes are stacked with a slight slope. Kra them from the lower side and. Have shutters.

The measuring device operates as follows.

Low consumption takes into account a triangular weir with an angle of 90 °, with an average consumption switch to trapezoidal. When the pass

The ability of this weir will be blocked, measurements are made on a horizontal concrete threshold of control.

With floods carrying a large amount of sediment, fine fractions, coarse sand and small pebbles are suspended and at high speeds at ca. Aibix are transported to a settling basin. The size of the sediment fractions carried through the living section increases as it approaches the bottom, and the velocity decreases. Large boulders in their movement significantly lag behind small ones, while elk ones are ahead of them throughout the whole section. The flow energy with sediments, reaching a basin with a significant cross section, decreases at the approaching threshold of the control in front of the basin. The river with sediments, rushing into the basin, loses its approaching velocity, the turbulence decreases sharply, and fine and coarse sand falls to the bottom of the basin. The process of falling out and zapolpeni pool occurs very quickly. By the approach of large fractions, the basin is completely filled and forms a channel channel in the direction and size of the cutout of the weir. The river bed is quickly formed in the basin itself. At this time, a section of the channel in the basin shows higher velocities than at the approach to the threshold. This is guaranteed by the slope between the threshold and the edge of the weir, which, compared to the false tone above the threshold, is much larger. Under these conditions, a continuous transition of large factions begins across the entire basin, through the spillway and further down the river.

Subject invention

An application for determining the flow of water on mountain rivers, carrying into the flood a significant amount of suspended and drawn sediments, a spillway measuring device, for which the latter is performed as a control threshold with a horizontal ridge serving for halogen fix measurements of floodwaters, thin-walled measured weirs with replaceable spillway shields, a settling basin located between the measured weir and the poro ™ control and the burned sloping drain pipes.