RU2375518C2 - Device for protecting coastal areas against floods - Google Patents

Abstract

FIELD: construction industry.

SUBSTANCE: invention refers to protection means of cities located by the sea and adjacent areas against floods and other natural hazards. Device consists of units-shutters located at the bottom in initial state. Lower angles of units are fixed at bottom supports with possibility of being turned. Units-shutters are made in the form of cast concrete designs of rectangular configuration with closed air cavities offset to upper floating edge of the unit, which compensate gravitation component of the unit at maintaining small negative floatation and which are made with the possibility of being lifted across the flow, pressed to limit stops and kept in inclined position with incoming flow. Upper floating edge of units-shutters is made in the form of inclined hydrodynamic visor directed opposite the flow induced with piled up wave.

EFFECT: invention allows decreasing construction and operational costs.

6 cl, 2 dwg

Description

The invention relates to means of protecting coastal cities from floods caused by surge waves or tsunamis with the help of dams and other engineering structures.

The city of St. Petersburg suffers from flood surges. At present, the construction of the St. Petersburg Flood Protection Complex (GLC) is nearing completion.

The complex will consist of two ship passage structures, six water passage structures, 11 protective dams stretching across the top of the Gulf of Finland from Izhora to Sestroretsk (Gorskaya village), through the island of Kotlin, on which the city of Kronstadt is located. The total length of the protective structures of St. Petersburg is 25.4 km. During the largest flood that St. Petersburg has ever experienced, the water level was 4.2 meters above the ordinary.

The maximum height of water rise that a complex of protective structures can withstand is 4.5 meters. Within three hours after the flood warning system has been triggered, these gates will be completely closed, so the possibility of flooding the coastal territories will be 100% excluded.

Another city in Europe, Venice, also suffers from devastating floods.

Finally, work began on the construction of a system of mobile dams to protect the wettest city in Europe from flooding. The grandiose project is called "Moses." Despite the fact that construction will begin only now, the project cannot be called new - it began to be developed 30 years ago.

The construction of the entire structure will cost about $ 7 billion.

It is known that over the past 100 years, Venice plunged into the water by 23 centimeters. In 1973, a unique city was declared a zone of national interest. The Moses project has been under development since 1966. The final construction plan was agreed only now.

Under normal weather conditions, when there is no surge wave from the sea, there is a normal flow of water through the canals of Venice into the lagoon. When a surge wave appears, the flows change direction, and the water entering the canals raises the water level in the city up to 2 meters. To create an obstacle for reverse waters in the city, a system of 79 blocks will be built on the Adriatic coast that will hold the rising sea and maintain an acceptable water level in the Venetian lagoon. Each block is 20 meters wide, from 20 to 30 meters high and 4 to 5 meters thick. These "pillows", until the sea level exceeds a certain limit, will lie on the bottom, filled with water. In the case of a rise of a meter or more, air is pumped into the blocks and thereby one of the edges is lifted. In all likelihood, it will be necessary to blow this temporary dam 50 times a year - approximately at such a frequency floods have occurred in Venice over the past two decades. By all accounts, she will be able to protect the city from a two-meter rise in water level.

Now Venice is subject to small and large flooding for about 200 days a year, and at the beginning of the 20th century this figure was 7 days.

Mankind in its arsenal in the fight against floods and floods has accumulated constructive experience. In the fight against this natural phenomenon, earthen dams and fence structures are used. But these structures impede normal ecology and often do not withstand the pressure of the elements, which leads to numerous irreparable human and material losses.

A device for flood protection is known, consisting of gate blocks lying on the bottom in the initial state, the lower corners of which are fixed in the bottom supports with the possibility of a turn, equipped with air cavities offset to the upper, pop-up edge of the block and providing positive buoyancy (see Smirnov G.N. et al. Ports and Port Structures, Moscow, Stroyizdat, 1979, p.303-310, Fig. XIV.7a). This known technical tool is the closest analogue (prototype) of the claimed invention, because has the largest number of matching features.

The aim of the claimed invention is to minimize the cost of the protective structure while maintaining high efficiency of protection against flooding and floods of coastal territories of coastal cities.

The essence of the invention lies in the fact that the gate blocks are provided with closed air cavities in the upper lifting part with respect to the bottom of the sea, and the upper part of the block is made in the form of an inclined hydrodynamic visor directed against the flow of water, the upper part of which is made with shock-absorbing edges, with reflective edges coating, and is also equipped with aerodynamic slots to mitigate the impact of the wave, and the base of the block has a limiting underwater stops that hold the block-valves in a predetermined position with rahovochnymi chains and optionally equipped belay latches preventing random oscillations of lock blocks and the blocks themselves-gates in the original, a submerged position designated signal buoys with autonomous lighting instruments.

A blocking valve for flood protection dam is offered. The device is a cast concrete structure of a rectangular configuration, with closed air cavities to compensate for the gravitational component of the block, while maintaining a small negative buoyancy. Air cavities are shifted to the upper, pop-up edge of the block, which is made in the form of a visor directed at an angle upward. The lower corners of the bolt block are fixed in the bottom supports in one way or another. In the initial state, the blocks lie at the bottom, without interfering with the natural flow of water from canals or rivers and without interfering with navigation. At the beginning of the flood, a surge wave moving from the side of the lagoon or gulf causes a backward movement of the water flow, which begins to put pressure on the inclined shutter visor, creating a lifting force, which sets the unit in motion, causing it to turn and ascend. The incoming flow, as the angle of inclination of the gate block increases, finally raises the gate block, which sits on the stops and remains in a vertical position, preventing the movement of the water flow of the surge wave until it is weakened. When the pressure from the side of the lagoon on the gate blocks weakens, they will again fall to the bottom of the bay under the influence of gravitational forces, without interfering with the natural flow of water from rivers and canals and without interfering with free navigation.

The positive effect of the use of shutter blocks of the proposed design is that there is no need to build compressor stations, communications and equipment to control and control the position of the shutter blocks, as well as significantly reduce the subsequent constant costs of electricity and maintenance of the entire protective structure.

Figure 1 and 2 shows the design of the protective structure, where the following notation is used:

1. Ground support.

2. Block shutter.

3. The air cavity.

4. Inclined hydrodynamic peak.

5. Shock absorbing edge.

6. Signal buoy.

7. Aerodynamic cracks.

8. Restrictive emphasis.

9. Safety chain.

10. Reflective coating.

11. Free flow.

12. Latch.

Figure 1 shows a fragment of a flood protection structure, where the bottom support (1), block gate (2), limit stop (8), safety chain (9), signal buoy (6).

Figure 2 shows the design of the shutter block (2) for the protective structure, where the air cavity (3), the inclined hydrodynamic peak (4), the aerodynamic cracks (7), the shock-absorbing edge (5), the reflective coating (10), the latch ( 12).

The proposed protective structure based on block valves (2) works as follows. In the initial state, the gate blocks (2) lie on the bottom of the bay, without creating obstacles to the natural flow of water from canals and / or rivers and the movement of ships. During a flood, a surge wave moving from the side of the lagoon causes a backward movement of the water flow, which begins to put pressure on the inclined hydrodynamic visor (4) and sets the block-gate (2) in motion, causing it to turn in the bottom supports (1) and emerge. The incoming flow (11) raises the block-valve (2) and presses it to the restrictive stops (8), holding it in an inclined position until the surge wave attenuates. When the pressure from the water flow to the blocking valve weakens, it will again fall to the bottom of the bay under the influence of gravitational forces, without interfering with the natural flow of water.

The position of the protective gate blocks (2) at the bottom of the bay is indicated by signal buoys (6), and when leaving the water, in the protective position, also visually due to the reflective coating (10) applied to the shock-absorbing edge (5).

Aerodynamic cracks (7) play a dual role, on the one hand, they increase the lifting tractive force acting, with a weak surge wave, on the pop-up edge of the bolt block, and on the other, relieves excessive pressure on the upper edge of the bolt block at a high speed of incoming flow, which allows you to reduce the requirements for the strength of the bolt blocks, and therefore save consumables.

The proposed “Device for the protection of coastal territories of the city from floods” reduces overall costs when designing a protective structure, does not require changes to the existing technology for the production of shut-off units, and also reduces costs during their subsequent operation.

Claims (6)

1. A device for protecting coastal territories from floods, consisting of gate blocks lying on the bottom in the initial state, the lower corners of which are fixed in the bottom supports with the possibility of a turn, equipped with air cavities offset to the upper, pop-up edge of the block, characterized in that shutter blocks are made in the form of cast concrete structures of a rectangular configuration with closed air cavities that compensate for the gravitational component of the block while maintaining a small negative buoyancy and GOVERNMENTAL raisably across the flow, being pressed against the limit stop and retention in the oblique incident flow position, the upper edge of the pop-gate units configured as a hydrodynamic oblique visor directed against flow induced surge wave. 2. The device according to claim 1, characterized in that aerodynamic cracks are made in the upper ends of the gate blocks. 3. The device according to claim 1, characterized in that the upper ends of the gate blocks are connected to the underwater supports by safety chains located against the incoming flow. 4. The device according to claim 1, characterized in that shock absorbing edges are installed on the upper edges of the gate blocks. 5. The device according to claim 1, characterized in that the position of the gate blocks in the initial state is indicated by signal buoys with light devices with autonomous non-volatile power supply. 6. The device according to claim 1, characterized in that the upper edges of the gate blocks are coated with reflective material.

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