Segmented cylindrical array dam blast protection structure with self-erecting capability

Abstract

This invention relates to the field of safety protection for hydraulic structures, and in particular to a segmented cylindrical array blast-resistant protection structure for dams with self-erecting capability. It comprises multiple protective mechanisms positioned upstream of a concrete gravity dam, between a potential underwater blast source and the dam. These protective mechanisms are arranged in a pre-defined array, with lightweight connecting members between adjacent mechanisms to maintain the array arrangement. Each protective mechanism is a segmented, modular structure, including several axially arranged hollow short pipe sections connected by chains. This invention, by arranging an adjustable cylindrical array protective structure in front of the concrete gravity dam, utilizes the multiple reflections, scattering, and energy dissipation effects of the cylindrical array on the underwater blast shock wave, significantly reducing the impact intensity on the dam surface and thus decreasing the dam's dynamic response.

Description

Technical Field

[0001] This invention relates to the field of safety protection for hydraulic structures, and in particular to a segmented cylindrical array dam blast-resistant protection structure with self-erecting capability. Background Technology

[0002] Concrete gravity dams are widely used in water conservancy, hydropower, and flood control projects, primarily relying on their own weight to maintain overall stability. In situations such as war, underwater blasting, or extreme accidents, underwater explosions can generate high-intensity shock waves in the water. These shock waves are characterized by rapid propagation and high peak pressure. When acting on the upstream side of the dam, they can easily cause deformation and failure of spillway gates, expansion of cracks in the dam body, and amplification of the overall dynamic response of the dam, potentially endangering the structural safety of the dam in severe cases.

[0003] To mitigate the direct impact of underwater blast shock waves on concrete gravity dams, various protective measures have been proposed in existing technologies, such as installing protective piles, energy dissipation components, or thickening the upstream structure. However, these protective schemes generally suffer from the following shortcomings: First, the protective components are mostly fixed structures, making construction complex and involving a large amount of work, often requiring modifications to the original dam structure; second, the parameters of the protective components are poorly adaptable, making it difficult to flexibly adjust them for different blast yields and water depths; third, existing schemes generally neglect the attitude stability of the protective components in the water, making them prone to tipping over, floating, or becoming unstable under hydrodynamic or blast impacts, thus severely weakening the protective effect; fourth, traditional protective components are bulky and rigid cylindrical, making them extremely inconvenient for land transportation and water hoisting, and the rigid structure is prone to stress concentration under strong shock waves, leading to brittle fracture or overall breakage.

[0004] Furthermore, existing research largely focuses on the external geometry of protective components or the blast resistance of the materials themselves, with few systematic considerations of the impact of the internal mass distribution of protective components on their attitude evolution in water, self-stabilizing ability, and protective reliability. Therefore, a segmented cylindrical array blast-resistant protective structure with self-erecting capability is proposed. Summary of the Invention

[0005] In view of the problems existing in the above or prior art, the present invention is proposed.

[0006] Therefore, the purpose of this invention is to provide a segmented cylindrical array dam blast-resistant protection structure with self-erecting capability.

[0007] To solve the above-mentioned technical problems, the present invention provides the following technical solution: including, Multiple protective structures are located in the waters upstream of the concrete gravity dam, between the potential underwater explosive source and the concrete gravity dam; The multiple protective mechanisms are arranged in a preset array.

[0008] As a preferred embodiment of the segmented cylindrical array dam blast-resistant protection structure with self-standing capability of the present invention, a lightweight connecting member is provided between adjacent protection mechanisms to maintain the array arrangement structure.

[0009] As a preferred embodiment of the segmented cylindrical array dam blast-resistant protection structure with self-erecting capability of the present invention, wherein: the protection mechanism is a segmented modular structure.

[0010] As a preferred embodiment of the segmented cylindrical array dam blast-resistant protection structure with self-erecting capability of the present invention, the protection mechanism includes a number of hollow short pipe sections arranged along the axial direction, and a chain connects two adjacent hollow short pipe sections.

[0011] As a preferred embodiment of the segmented cylindrical array dam blast-resistant protection structure with self-standing capability of the present invention, wherein: the bottom hollow short pipe section of the protection mechanism is filled with high-density polymer crushed stone material.

[0012] As a preferred embodiment of the segmented cylindrical array dam blast-resistant protection structure with self-standing capability of the present invention, wherein: the upper hollow short pipe section is either empty or filled with low-density material.

[0013] As a preferred embodiment of the segmented cylindrical array dam blast-resistant protection structure with self-standing capability of the present invention, wherein: the center of gravity of the entire protection mechanism is located below its drainage volume center, i.e., the comprehensive buoyancy center.

[0014] As a preferred embodiment of the segmented cylindrical array dam blast-resistant protection structure with self-erecting capability of the present invention, wherein: the protection mechanism has self-erecting capability in water.

[0015] As a preferred embodiment of the segmented cylindrical array dam blast-resistant protection structure with self-standing capability of the present invention, wherein: the center distance between adjacent protection mechanisms is set to 2D to 3D based on the diameter D of the protection mechanism, and the lightweight connecting member is used to fix and maintain the center distance.

[0016] As a preferred embodiment of the segmented cylindrical array dam blast-resistant protection structure with self-erecting capability of the present invention, the protection mechanism is arranged in a single row or multiple rows; in the case of multiple rows, the arrangement includes orthogonal arrangement, staggered arrangement or other combination forms.

[0017] The beneficial effects of the segmented cylindrical array dam blast-resistant protection structure with self-erecting capability of the present invention are as follows: 1. The present invention arranges a cylindrical array protection structure with adjustable parameters in front of a concrete gravity dam, and utilizes the multiple reflections, scattering and energy dissipation effects of the cylindrical array on the underwater explosion shock wave to significantly reduce the impact intensity acting on the dam surface, thereby reducing the dynamic response of the dam.

[0018] 2. This invention regulates the material density distribution in the upper and lower regions of the protective mechanism and utilizes the mechanical principle of "center of gravity lower than center of buoyancy" to ensure that the protective component can automatically change from a horizontal to a vertical posture in water without the need for auxiliary equipment. It also has extremely strong anti-overturning stability and avoids instability under impact loads.

[0019] 3. The present invention adds lightweight connecting components between the protective mechanisms, which can effectively prevent the cylinders from drifting randomly under the disturbance of water flow or explosion shock waves, ensuring that the array structure always maintains the designed shape and spacing, and the lightweight material does not affect the self-standing ability of the individual units, thereby ensuring a stable and controllable energy dissipation and explosion protection effect.

[0020] 4. This invention adopts a design of hollow short pipe sections with segmented chain connections, combined with the on-site in-situ rapid filling process of polymer crushed stone, breaking down the whole into parts, which greatly reduces the difficulty of land transportation and hoisting of ultra-long components; the on-site rapid assembly and grouting method can be flexibly adjusted according to the water depth, and has excellent engineering adaptability.

[0021] 5. This invention introduces a parameterized array design method based on the cylinder diameter. By adjusting the cylinder array spacing, arrangement, and number of array rows, the protective effect can be flexibly controlled, which has good engineering adaptability.

[0022] 6. The present invention has a simple structure and can be prefabricated and deployed directly, which reduces the difficulty and cost of underwater construction. It can achieve underwater explosion protection without changing the original structure of the concrete gravity dam, and has high engineering application value. Attached Figure Description

[0023] To more clearly illustrate the technical solutions of the embodiments of the present invention, the drawings used in the following description of the embodiments will be briefly introduced. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0024] Figure 1 This is a schematic diagram of the array-protected dam body involved in an embodiment of the present invention; Figure 2 This is a schematic diagram illustrating the reduction of the reflection of the explosion shock wave by the array according to an embodiment of the present invention; Figure 3This is a top view of an array structure with a 3D cylinder spacing according to an embodiment of the present invention; Figure 4 This is a top view of an array structure with a cylindrical spacing of 2.5D according to an embodiment of the present invention; Figure 5 This is a top view of an array structure with a cylindrical spacing of 2D according to an embodiment of the present invention; Figure 6 This is a longitudinal cross-sectional schematic diagram of a protective mechanism with a segmented filling connection structure according to an embodiment of the present invention; Figure 7 This is a schematic diagram of a fillable protective mechanism according to an embodiment of the present invention; Figure 8 This is a schematic diagram of the initial state of the protective mechanism involved in the embodiment of the present invention when it enters the water body in a horizontal state. Figure 9 This is a schematic diagram illustrating the force distribution of the protective mechanism involved in the embodiment of the present invention as it gradually rotates from a horizontal state to an upright state in water under the action of buoyancy. Figure 10 This is a schematic diagram of the protective mechanism involved in the embodiment of the present invention, which is partially exposed above the water surface in a vertical state and remains stably suspended.

[0025] In the diagram: 100, protective mechanism; 101, hollow short pipe section; 102, chain. Detailed Implementation

[0026] To make the above-mentioned objects, features and advantages of the present invention more apparent and understandable, the specific embodiments of the present invention will be described in detail below with reference to the accompanying drawings.

[0027] Example 1, referring to Figures 1-7 This is the first embodiment of the present invention, which provides a segmented cylindrical array dam blast-resistant protection structure with self-erecting capability, which includes a protection mechanism 100.

[0028] Specifically, the segmented cylindrical array dam blast protection structure includes several protection mechanisms 100, which are set in the upstream waters of the concrete gravity dam, located between the potential underwater blast source and the concrete gravity dam. The protection mechanisms 100 are arranged in a preset array, and lightweight connecting components are provided between adjacent protection mechanisms 100 to maintain the array arrangement structure. The protective mechanism 100 is a segmented modular structure that is quickly assembled on-site from multiple hollow short pipe sections 101 along the axial direction using chains 102.

[0029] Preferably, the bottom pipe section of the protective mechanism 100 is filled with high-density polymer crushed stone material in situ on site, while the upper pipe section is left empty or filled with low-density material, so that the center of gravity of the protective mechanism 100 is located below its drainage volume center, i.e., the overall center of buoyancy; when the protective mechanism 100 is in a free-floating state, its total weight G and its maximum drainage buoyancy F when fully submerged are... max Satisfies: 0.6≤G / F max ≤1.0.

[0030] Furthermore, the protective mechanism 100 has the ability to stand upright in the water. When the protective mechanism 100 is deployed into the water in a horizontal or inclined posture, since the overall center of gravity is located below the overall center of buoyancy, when the center of buoyancy and the center of gravity do not coincide, the buoyancy and gravity form a restoring torque, which drives the segmented pipe sections of the protective mechanism 100 to automatically rotate and coordinate to change to a vertical posture until a stable equilibrium state is reached.

[0031] In the cylindrical array, the center distance between adjacent protective mechanisms 100 is set to 2D to 3D based on the diameter D of the protective mechanism 100, and a lightweight connecting member is used to fix and maintain this center distance.

[0032] Cylindrical arrays can be arranged in single or multiple rows; in the case of multiple rows, the arrangement can be orthogonal, staggered, or other combinations.

[0033] Example 2, refer to Figures 1-7 This is the second embodiment of the present invention. Unlike the previous embodiment, this embodiment provides a parameterized design method for a cylindrical array protective structure with self-standing capability, including the following steps: By adjusting the outer diameter, total length, wall thickness, and filling state of each segment of the cylindrical unit, the cylindrical unit can meet one of the following conditions in a vertical position: (1) Floating mode: The total weight G of the cylindrical unit and the maximum displacement buoyancy F max The ratio ranges from 0.6 to 0.8, allowing it to retain a certain amount of reserve buoyancy in equilibrium, with the top part protruding above the water surface; (2) Suspension mode: The total weight G of the cylindrical unit and the maximum displacement buoyancy F max The ratio ranges from 0.9 to 1.0, which puts it in a critical suspension state of full immersion in water.

[0034] To further demonstrate the convenience of segmented modular design in engineering implementation, the protective mechanism 100 in this embodiment adopts a construction process of on-site assembly and partition filling. The specific deployment process is as follows: (1) Lightweight transportation: The unfilled aluminum alloy hollow short pipe section 101, chains and counterweight materials were transported to the dam or construction water site respectively. The hollow short pipe section 101 effectively solved the problem of limited land transportation of traditional ultra-large protective components; (2) On-site flexible splicing: On the shore assembly site or construction vessel, multiple hollow short pipe sections 101 are arranged in sequence according to the preset total length, and the ends of adjacent pipe sections are reliably hinged by short metal chains to form the main body of the multi-segment flexible protection mechanism 100. (3) Filling of the bottom pipe section: According to the design requirements of the water depth and explosion-proof parameters on site, inject precisely measured high-density counterweight material (such as polymer crushed stone) into several designated pipe sections located at the bottom of the array, and strictly waterproof and seal the injection port; the upper pipe section is kept empty and sealed (or filled with low-density foam) to provide the necessary drainage buoyancy. (4) Self-erecting deployment upon entering the water: Using ordinary on-site lifting equipment or a slide, the assembled and filled protective mechanism 100 is directly deployed to the target water area in a horizontal or any tilted posture. Relying on the "center of gravity shifting downward" effect formed by the high-density filling of the bottom pipe section, the protective mechanism 100 can automatically rotate and be firmly locked in a vertical floating or suspended posture under the combined action of gravity and buoyancy after entering the water, thus completing the deployment.

[0035] Assume that the water depth at the site requires a protection unit with a total effective protection length of L=10m.

[0036] The protective mechanism 100 adopts a segmented modular design, consisting of multiple hollow short aluminum alloy tube segments 101 with an outer diameter D=1m and a wall thickness δ=10mm (material density approximately 2700kg / m3), and the short tube segments are connected by lightweight metal short chains.

[0037] Total volume of the cylinder when fully submerged:

[0038] Maximum displacement buoyancy equivalent mass:

[0039] To retain 20% reserve buoyancy (i.e., G / F) max ≈0.8), The system's target total mass is set as follows:

[0040] Total mass of aluminum alloy pipe section:

[0041] Total mass of aluminum alloy connecting chain:

[0042] The required mass of high-density filler material is

[0043] To ensure the multi-section flexible system remains upright in water, polymer crushed stone (density approximately 2300 kg / m³) was selected. 3 As a counterweight, it is concentrated in the bottom few pipe sections.

[0044] The required volume of polymer crushed stone can be calculated to be approximately:

[0045] Equivalent fill height:

[0046] Under stable floating conditions (total draft 8m), the overall buoyancy height of the system is:

[0047] After calculation, the overall center of gravity height of the system is...

[0048] By H G ≪H B Even if the component is launched horizontally, gravity and buoyancy will generate a strong positive restoring torque, pulling the multi-segment chain structure to automatically complete the vertical deployment. The cylindrical unit exhibits a bottom-heavy and top-light mass distribution (e.g., Figure 6 , Figure 7 As shown) to ensure the center of gravity is always below the overall center of buoyancy, when the cylindrical unit enters the water in a horizontal or inclined manner (such as... Figure 8 As shown) the driving unit gradually rotates in the water (as shown) Figure 9 As shown), until a stable vertical equilibrium state is achieved ( Figure 10 ).

[0049] Furthermore, the protective mechanism 100 adopts a construction process of on-site partitioned filling and flexible assembly; during the transportation phase, the hollow short pipe sections 101, chains 102 and filling materials are independent components to achieve lightweight transportation; during the installation phase, multiple hollow short pipe sections 101 are sequentially hinged together using chains 102, and according to the depth of the service water area and the explosion-proof requirements, only a specified number of hollow short pipe sections 101 at the bottom are filled with high-density materials and sealed to achieve on-site adjustment and attitude locking of the center of gravity and buoyancy position.

[0050] In addition to being used for the protection of concrete gravity dams, the protective structure can also be applied to the blast and collision protection of hydraulic structures such as bridge piers, port terminals, underwater tunnels, or offshore platforms by adjusting the arrangement geometry and individual parameters of the cylindrical array.

[0051] Example 3 like Figure 2 and Figure 3 As shown, three rows of cylindrical array protective structures are arranged in the upstream waters of a concrete gravity dam. The cylindrical array consists of multiple protective mechanisms 100, all with the same diameter D. The center-to-center distance between adjacent protective mechanisms 100 is set to three times the diameter of the cylinder (3D). Figure 3 As shown, the various protective mechanisms 100 are connected by lightweight constraint rods or rope nets to form a stable grid topology. The lightweight connecting material is only used to maintain the relative position between the cylinders and does not increase the upper counterweight of the system.

[0052] In this embodiment, the protective mechanism 100 is designed in a "floating mode". By adjusting the counterweight, the self-weight G of the protective mechanism 100 is controlled to be approximately equal to its maximum displacement buoyancy F. max 80% (i.e., G / F) max ≈0.8). When an underwater explosion occurs, the shock wave first interacts with the cylindrical array during its propagation, and the shock wave is reflected and scattered on the cylindrical surface. Since the top part of the protective mechanism 100 is exposed above the water surface, it is convenient for construction personnel to observe and maintain it, and the reserved buoyancy allows it to quickly return to a vertical and stable state after an instantaneous swaying caused by the impact.

[0053] Example 4 like Figure 4 and Figure 5 As shown, in another embodiment, the cylindrical array is arranged in a staggered manner, with the center distance between adjacent protective mechanisms 100 set to 2.5 times (2.5D) and 2 times (2D) the diameter of the cylinder, respectively. Similarly, lightweight fixed connections are evenly distributed between adjacent protective mechanisms 100 to ensure that the multiple rows of cylinders will not collide with each other or deform due to hydrodynamic forces in the suspended state.

[0054] In this embodiment, the protective mechanism 100 is designed in a "floating mode". By precisely adjusting the internal filling material, the maximum buoyancy of the protective mechanism 100 is made approximately equal to its own weight (G / F). max (≈0.9~1.0). At this time, the protective mechanism 100 is in a critically suspended state of full immersion, with only the top slightly exposed or completely submerged below the water surface. This staggered arrangement combined with the suspended state not only provides strong concealment and is less affected by the dynamic effects of water surface waves, but also makes the underwater explosion shock wave form a more complex propagation path in the array, significantly enhancing the overall energy dissipation capacity of the cylindrical array.

[0055] It should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention and are not intended to limit it. Although the present invention has been described in detail with reference to preferred embodiments, those skilled in the art should understand that modifications or equivalent substitutions can be made to the technical solutions of the present invention without departing from the spirit and scope of the technical solutions of the present invention, and all such modifications or substitutions should be covered within the scope of the claims of the present invention.

Claims

1. A segmented cylindrical array dam blast-resistant protection structure with self-erecting capability, characterized in that: include, Multiple protective structures (100) are located in the waters upstream of the concrete gravity dam, between the potential underwater blast source and the concrete gravity dam; The multiple protective mechanisms (100) are arranged in a preset array.

2. The segmented cylindrical array dam blast-resistant protection structure with self-erecting capability as described in claim 1, characterized in that: Lightweight connecting members are provided between adjacent protective mechanisms (100) to maintain the array arrangement structure.

3. The segmented cylindrical array dam blast-resistant protection structure with self-erecting capability as described in claim 2, characterized in that: The protective mechanism (100) is a segmented modular structure.

4. The segmented cylindrical array dam blast-resistant protection structure with self-erecting capability as described in claim 3, characterized in that: The protective mechanism (100) includes a plurality of hollow short pipe sections (101) arranged along the axial direction, and a chain (102) connects two adjacent hollow short pipe sections (101).

5. The segmented cylindrical array dam blast-resistant protection structure with self-erecting capability as described in claim 4, characterized in that: The bottom hollow short tube section (101) of the protective mechanism (100) is filled with high-density polymer crushed stone material.

6. The segmented cylindrical array dam blast-resistant protection structure with self-erecting capability as described in claim 5, characterized in that: The upper hollow short tube section (101) is either empty or filled with low-density material.

7. The segmented cylindrical array dam blast-resistant protection structure with self-erecting capability as described in claim 6, characterized in that: The center of gravity of the protective mechanism (100) is located below its drainage volume center, i.e., the overall buoyancy center.

8. The segmented cylindrical array dam blast-resistant protection structure with self-erecting capability as described in claim 7, characterized in that: The protective mechanism (100) has the ability to stand upright in water.

9. The segmented cylindrical array dam blast-resistant protection structure with self-erecting capability as described in claim 8, characterized in that: The center distance between adjacent protective mechanisms (100) is set to 2D to 3D based on the diameter D of the protective mechanism (100), and the lightweight connecting member is used to fix and maintain this center distance.

10. The segmented cylindrical array dam blast-resistant protection structure with self-erecting capability as described in claim 9, characterized in that: The protective mechanism (100) is arranged in a single row or multiple rows; in the case of multiple rows, the arrangement includes orthogonal arrangement, staggered arrangement or other combination forms.

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