A flexible protective device for attenuating the load of a waterborne blast wave

Abstract

The present application belongs to the field of engineering safety technology, and discloses a flexible protection device for weakening water explosion shock wave load. The disclosed flexible protection device for weakening water explosion shock wave load has a floating cylinder which can float in water; a bubble film is wound on the floating cylinder; the bubble film is wound in multiple layers on the floating cylinder, and the innermost layer of the bubble film is fixedly connected with the floating cylinder; the end of the innermost layer of the bubble film is connected with a counterweight clamp; the multiple layers of the bubble film are arranged vertically in water by using the gravity of the counterweight clamp and the buoyancy of the floating cylinder, and form an air layer for attenuating water explosion shock wave. The present application can protect the surrounding structure during underwater blasting demolition, and reduce the damage and destruction of the underwater components of high-pile wharf, caisson wharf, cross-sea bridge, river-crossing tunnel and other structures under accidental or intentional explosion load.

Description

TECHNICAL FIELD

[0001] The present application belongs to the field of engineering safety technology, and particularly relates to a flexible protection device for weakening water explosion shock wave load. BACKGROUND

[0002] According to the literature research and the relevant information query result, it is found that the existing underwater explosion protection technology measures mainly serve the warships, submarines and other weapon equipments, and the most commonly used protection forms mainly include the following three kinds. The first kind is to lay a large number of impact-resistant tiles with a cavity on the surface of the warship, which is composed of an inner surface layer and an outer surface layer with rubber material as a base material and a special cavity structure core layer sandwiched in the middle, and the inner surface is pasted with the outer plate of the warship through an adhesive. The second kind is to use a steel-foam sandwich plate or other special structure instead of the original steel structure as the outer plate of the ship body, so that the energy absorption effect of the foam or other special structure can be utilized. The third kind is to arrange a mine protection cabin on the side of the warship, and the outermost layer is a cavity, which can quickly attenuate the shock wave in the water and provide a space for the deformation of the outer plate; the second layer from the outside is a liquid cabin, which mainly serves to attenuate the speed of the explosion fragments and the outer plate fragments; and the third layer is a cavity to further block the damage of the shock wave to the basic protection plate.

[0003] However, the underwater explosion engineering protection technology research carried out at home and abroad for the coastal support platform and major water conservancy dams and other large-scale structure facilities is relatively few, and at present, the bubble curtain is mainly used to attenuate the underwater explosion shock wave, but the bubble curtain has many disadvantages for underwater explosion protection, such as the need for multiple high-power air compressors to work simultaneously for large-area protection, difficulty in laying and fixing in deep water, and most importantly, the time of underwater accidental explosion cannot be known, that is, the bubble curtain belongs to a continuous consumption type of protection technology measure, which has many limitations in engineering application. Therefore, it is of great significance and practical value to develop a convenient and non-continuous consumption type of underwater explosion shock wave weakening device. SUMMARY

[0004] In order to solve the above problems, the present application aims to provide a flexible protection device for weakening water explosion shock wave load.

[0005] The present application adopts the following technical scheme to achieve the above-mentioned purpose:

[0006] A flexible protection device for weakening underwater explosion shock wave load, the flexible protection device has a floating cylinder which can float in water; a bubble film is wound on the floating cylinder; the bubble film is wound in multiple layers on the floating cylinder, and the innermost layer of the bubble film is fixedly connected with the floating cylinder; an end of the innermost layer of the bubble film is connected with a counterweight clamp; the multiple layers of the bubble film are arranged vertically in water by using the gravity of the counterweight clamp and the buoyancy of the floating cylinder, and form an air layer for attenuating the underwater explosion shock wave; the bubble film wraps a large number of small-volume air bubbles which cannot freely float upwards due to the sealing limitation of the film and can long stay in the water body, so that the multiple layers of the bubble film can form an air layer with a certain thickness in water without external energy consumption; the underwater explosion shock wave is attenuated by using the wave impedance mismatch principle; in addition, the deformation energy absorption of the polyethylene film and the disturbance of the local turbulence generated by the dense bubbles to the propagation path of the shock wave can further weaken the intensity of the shock wave.

[0007] The counterweight clamp is a stainless steel plate clamped at the lower part of the bubble film.

[0008] The floating cylinder is a PVC plastic pipe with sealed two ends.

[0009] The two ends of the counterweight clamp are respectively connected with floating balls through traction ropes.

[0010] The flexible protection device for weakening underwater explosion shock wave load is proposed, which can limit a certain amount of air in water by multiple layers of polyethylene bubble film to form an air layer; since the wave impedance of air is much smaller than that of water, when the underwater explosion shock wave propagates to the interface between air and water, the underwater shock wave will mainly be reflected at the medium interface, and the transmission coefficient is small, only a small part of energy is transmitted to the air medium, so the underwater shock wave can be effectively buffered to weaken the explosion damage effect.

[0011] Compared with the free bubble curtain, the device does not need to continuously input pressure gas to maintain the proportion of air in water, and is green and non-consumable; in addition, the vertical length of the bubble film can be changed according to different water depths, the number of layers of the bubble film can be designed according to the predicted load, and multiple devices can be arranged side by side for a larger protection surface width; when used, the device is placed on the water surface after the binding rope is untied, the counterweight clamp sinks under the action of gravity, the bubble film roll column can be rotated and unfolded, and the position of the device can be adjusted through the traction rope, so that the device is very convenient and efficient to arrange.

[0012] The present application can protect surrounding structures during underwater blasting demolition, and reduce damage and destruction of underwater components of high-pile wharfs, caisson wharfs, sea-crossing bridges and river-crossing tunnels under accidental or intentional explosion load. BRIEF DESCRIPTION OF DRAWINGS

[0013] Figure 1 A schematic diagram of the deployed state of the underwater explosion shock wave weakening device designed for the present application.

[0014] Figure 2 A front view of the storage state of the underwater explosion shock wave weakening device designed for the present application.

[0015] Figure 3 A Figure 2 side view.

[0016] In the figure: 1, bubble film; 2 floating cylinder; 3 counterweight clamping plate; 4 traction rope; 5 floating ball. DETAILED DESCRIPTION

[0017] In order to facilitate those skilled in the art to understand and implement the present patent, the present application will be further described in detail below in conjunction with the drawings and specific embodiments.

[0018] As Figure 1As shown, a flexible protection device for weakening the water explosion shock wave load, which is composed of bubble film 1, floating cylinder 2, counterweight clamp plate 3, traction rope 4 and floating ball 5. The bubble film 1 is a multi-layer conventional and customized thickened polyethylene air flexible bubble film, which has good buffering and energy absorption effect, and is usually used as packaging material for goods to reduce or prevent damage caused by falling and extrusion; the polyethylene bubble film wraps a large number of independent small-volume air, which cannot freely float upward due to the sealing limitation of the film and can be long-term stagnant in the water body, so the multi-layer bubble film superposition can form an air separation layer with a certain thickness in the water without external energy-consuming air supply; the shock wave in the water is attenuated by using the wave impedance mismatch principle; in addition, the deformation of the polyethylene film and the local turbulence generated by the dense bubbles can further weaken the intensity of the shock wave; the relatively large width of the polyethylene bubble film on the market is about 1m, if a larger protection surface width is needed, a wider bubble film can be customized or a transparent tape can be used to splice multiple bubble films; or multiple protection devices with insufficient width are arranged side by side. The floating cylinder 2 is usually composed of a PVC plastic pipe with a diameter of 100mm and sealed at both ends, which can provide additional buoyancy in the water to increase the stability of the bubble film against water flow impact, and can also serve as a reel core to provide stress support for storage; when in use, the bubble film is wound about two turns on it, and then fixed by uniformly perforating and bundling with plastic straps, ropes or steel wires, etc. The counterweight clamp plate 3 is usually processed from a long strip-shaped stainless steel plate with a cross-sectional thickness of 15mm and a height of 40mm, and the length of the steel plate is determined according to the protection width of the device; usually, holes with a spacing of 150mm are reserved on the steel plate, and transverse serrations are usually arranged on the inner surface of the steel plate to increase the clamping effect of the steel plate; after two steel plates clamp the multi-layer bubble film, the bolts are tightened or other fastening methods are used for fixation; the traction rope 4 is usually made of water-resistant soft rope, and the length is appropriately determined according to the water depth; one end is tied to the counterweight clamp plate, which is used to bundle the entire device in the storage state, and the free end is tied or buckled to the floating ball in the expanded use state to prevent the traction rope from falling to the bottom of the water and facilitate finding; if you want to adjust the position of the device, you can drag the counterweight clamp plate on the bottom of the water through the traction rope; if you want to take away the used device, you can take out the counterweight clamp plate from the water surface and then store it. The floating ball 5 is usually a closed plastic ball or other small floating objects, usually with holes or buckles to facilitate connection with the traction rope.

[0019] The air bubble film has light self-weight and large buoyancy in water. In order to smoothly deploy the air bubble film in water, a certain counterweight is arranged at the lower part of the air bubble film. The counterweight adopts two stainless steel plates clamping the lower part of the air bubble film, and the steel plates are uniformly and spacedly provided with holes which can be fastened by bolts. If the number of layers of the air bubble film is increased to need a larger mass of the counterweight, the number of the modular steel plates can be increased according to the need, and the corresponding length of the bolts is used for fastening.

[0020] Before deployment, the device is in a storage state for the convenience of storage and space saving. In the storage state, the floating cylinder is used as a reel, the air bubble film is entirely rolled up along the longitudinal direction until the counterweight clamping plate is close to the air bubble film cylinder, at this time, the two traction ropes of the counterweight clamping plate just serve as the binding ropes to bundle and fix the whole device.

[0021] The above example is only one embodiment of the present application. The specific structure and size can be adjusted according to the actual need. It should be pointed out that for ordinary skilled in the art, without departing from the concept of the present application, a number of modifications and improvements can be made, which are all within the protection scope of the present application.

Claims

1. A flexible protective device for weakening the load of an underwater explosion shock wave, characterized in that: The flexible protective device has a floating cylinder that can float in water; the floating cylinder is wrapped with bubble film; the bubble film is multiple layers wrapped around the floating cylinder, and the innermost bubble film is fixedly connected to the floating cylinder; the end of the innermost bubble film is connected to a counterweight plate; the multiple layers of bubble film are positioned vertically in the water using the weight of the counterweight plate and the buoyancy of the floating cylinder, forming an air gap to attenuate the explosive shock wave in the water; the bubble film encapsulates a large number of independent small volumes of air, which cannot float freely when in the water due to the sealing restriction of the film, and can remain stationary in the water for a long time. Therefore, the multiple layers of bubble film can form an air gap of a certain thickness in the water without the need for external energy supply; the principle of wave impedance mismatch is used to attenuate the explosive shock wave in the water; in addition, while the shock wave is squeezing the bubbles to burst, the deformation and energy absorption of the polyethylene film, as well as the disturbance of the shock wave propagation path by the local turbulence generated by the dense bubbles, can further weaken the intensity of the shock wave; the bubble film is a multi-layered conventional and custom-made thickened polyethylene flexible bubble film.

2. The flexible protective device for weakening the load of an underwater explosion shock wave as described in claim 1, characterized in that: The counterweight clamp is a stainless steel plate that is clamped under the bubble wrap.

3. A flexible protective device for weakening the load of an underwater explosion shock wave as described in claim 1, characterized in that: The floating cylinder is a PVC plastic pipe sealed at both ends.

4. A flexible protective device for weakening the load of an underwater explosion shock wave as described in claim 1, characterized in that: The two ends of the counterweight clamp are each connected to a floating ball by a traction rope.

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