A kind of debris flow blocking dam composite damping energy dissipation structure and design method for preventing large stone impact

Abstract

The application discloses a kind of mud-rock flow blocking dam composite shock-absorbing energy dissipation structures and design methods of preventing big stone block impact, the structure includes dam body, high damping rubber pad, composite shock absorber and impact-resistant steel plate, high damping rubber pad is fixed on dam body slope, its surface is provided with several composite shock absorbers, and impact-resistant steel plate is laid on the top of composite shock absorber;Composite shock absorber includes composite shock-absorbing unit, top plate and bottom plate, and top plate and bottom plate are fixedly connected with impact-resistant steel plate and high damping rubber pad respectively;Composite shock-absorbing unit includes composite material layer, disc spring layer, partition steel plate and compression spring, and the outside circumference of composite shock-absorbing unit is uniformly provided with several U-shaped dampers.The application cooperates high damping rubber pad, composite shock absorber and U-shaped damper to complete hierarchical energy dissipation and shock-absorbing, effectively absorbs and disperses the impact energy of big stone block in mud-rock flow, reduces dam stress concentration and damage risk, and can significantly improve the safety and service life of mud-rock flow defense system.

Description

Technical Field

[0001] This invention belongs to the field of debris flow prevention and control engineering technology, and in particular relates to a composite vibration reduction and energy dissipation structure and design method for debris flow retaining dams that are protected against the impact of large rocks. Background Technology

[0002] Debris flows are a serious threat prevalent in mountainous areas and regions prone to geological disasters, characterized by their sudden onset, large scale, and extreme destructive power. During their high-speed movement, debris flows often carry large amounts of mud, sand, gravel, and even large boulders, forming high-energy impact flows that cause significant damage to roads, bridges, dams, and various protective facilities along their path. In particular, when debris flows impact protective structures such as dams, they can trigger instantaneous and intense erosion and high-energy impacts, leading to the peeling of surface materials, the expansion of cracks, and the destruction of local components, thereby weakening the stability and reliability of the overall defense system.

[0003] Existing debris flow protection measures mainly include rigid retaining walls, reinforced concrete facing, riprap slope protection, or high wear-resistant steel plates. These methods improve structural strength and durability to some extent and can disperse some impact force, but they are mostly based on rigid impact resistance and lack systematic vibration reduction and energy dissipation mechanisms. When encountering high-energy debris flows with multiple impacts or large boulders, the concentrated impact energy can easily lead to brittle failure, causing local or even overall structural failure. At the same time, debris flow disasters are unpredictable and recurring. Protective structures often suffer fatigue damage under long-term and frequent impacts, with accelerated surface wear, expanded internal cracks, and a gradual decline in protective performance. Traditional methods relying on thick reinforcement or high-strength rigid facing can improve short-term impact resistance, but they are difficult to balance energy dissipation and buffering requirements, and have high maintenance costs. Summary of the Invention

[0004] In view of the technical problems and defects of existing debris flow protection structures, the purpose of this invention is to provide a new type of composite vibration reduction and energy dissipation structure, which can effectively absorb and disperse the impact energy of debris flow through multi-stage energy dissipation and elastic buffering while ensuring the overall strength of the retaining dam, reduce stress concentration and structural damage risk, and significantly enhance the safety and service life of the debris flow defense system.

[0005] To achieve the above objectives, the present invention provides the following technical solution:

[0006] A composite vibration damping and energy dissipation structure for debris flow retaining dams to prevent impact from large boulders includes a dam body, a high-damping rubber pad, composite dampers, and an impact-resistant steel plate. The high-damping rubber pad is laid on the sloping surface of the dam body, and several composite dampers are arranged on the surface of the high-damping rubber pad. The impact-resistant steel plate is laid on top of the composite dampers. Each composite damper includes a composite damping unit, with a top plate and a bottom plate respectively provided at the top and bottom. The top plate and bottom plate are fixedly connected to the impact-resistant steel plate and the high-damping rubber pad, respectively. Each composite damping unit includes several composite material layers, several disc spring layers, several partition steel plates, and a central compression spring. The composite material layers and disc spring layers are alternately stacked and separated by the partition steel plates. The central compression spring passes through the center of the composite material layers, disc spring layers, and partition steel plates, and its two ends are fixedly connected to the top plate and the bottom plate, respectively.

[0007] Preferably, the disc spring layer is a disc spring group composed of several large disc springs arranged longitudinally, the outer diameter of the large disc springs is the same as the outer diameter of the composite damping unit, and the central compression spring passes through the central hole of the large disc springs.

[0008] Preferably, the disc spring layer includes several disc spring groups, which are arranged horizontally in a circular array. Each disc spring group is composed of several small disc springs arranged longitudinally, and the outer diameter of each small disc spring is smaller than the radius of the composite damping unit.

[0009] Preferably, the composite damping unit further includes several thin compression springs, which pass through the central hole of the disc spring assembly and are fixedly connected at both ends to the top plate and the bottom plate, respectively.

[0010] Preferably, a plurality of U-shaped dampers are evenly arranged on the outer circumference of the composite damping unit, and the upper and lower side plates of the U-shaped dampers are respectively connected to the top plate and the bottom plate.

[0011] Preferably, the upper side plate, top plate, and impact-resistant steel plate of the U-shaped damper are fixedly connected by bolts; anchor bolts are pre-embedded on the inclined surface of the dam body, and the lower side plate, bottom plate, and high-damping rubber pad of the U-shaped damper are fixedly connected by the anchor bolts and nuts.

[0012] Preferably, the outer circumference of the composite damping unit is wrapped with a rubber protective layer.

[0013] This invention further proposes a design method for a composite vibration reduction and energy dissipation structure for debris flow retaining dams to prevent impact from large rocks. The method includes the following steps:

[0014] S1. Based on historical debris flow data of the debris flow gully, the debris flow impact energy is roughly calculated, and a safety margin is introduced to further determine the design energy of the composite vibration reduction and energy dissipation structure of the retaining dam; the formula for calculating the debris flow impact energy is:

[0015] ;

[0016] The design energy of the composite vibration reduction and energy dissipation structure of the retaining dam is:

[0017] ;

[0018] in, The first in the mudslide The quality of the stone block For the first The speed of the stone blocks The instantaneous impact pressure of the mudflow. Let be a function of mudflow velocity as a function of time. This represents the total number of rocks in the debris flow. The design energy of the composite vibration reduction and energy dissipation structure for retaining dams. For safety margin, This refers to the impact energy of a debris flow.

[0019] S2. The design energy of the composite vibration reduction and energy dissipation structure of the retaining dam is weighted and distributed to the high-damping rubber pad, composite damper and U-shaped damper. The energy absorption formulas of the high-damping rubber pad, composite damper and U-shaped damper are determined by force analysis. The structural parameters are initially designed according to the energy absorption formulas of each part and the energy distribution.

[0020] S3. Establish a finite element model of the composite vibration reduction and energy dissipation structure of the debris flow barrier dam, apply debris flow impact load, and analyze the stress, deformation and energy distribution of each layer; adjust the structural parameters of the high-damping rubber pad, composite damper and U-shaped damper to make the instantaneous stress peak less than the allowable stress; and verify the structural recovery ability after multiple impacts to ensure that the structure can be reused.

[0021] Further, in step S2, the energy absorption formula of the high-damping rubber pad is:

[0022] ;

[0023] in, To distribute the energy to the high-damping rubber pad, The equivalent stiffness of the high-damping rubber pad. The thickness of the high-damping rubber pad, The compression ratio of the high-damping rubber pad material;

[0024] The energy absorption formula of the composite shock absorber is:

[0025] ; ;

[0026] in, The energy borne by a single composite shock absorber The number of composite shock absorbers, The energy allocated to the composite shock absorber, The number of layers in the composite layer and disc spring layer. For the first The equivalent stiffness of the composite material layers in the layered composite structure, For the first The deformation of the composite material layer in the layered composite structure. For the first The stiffness of the disc spring layer in the layered composite structure. For the first The compression of the disc spring layer in the layered composite layer;

[0027] The energy absorption formula of the U-shaped damper is:

[0028] ; ;

[0029] in, The energy borne by a single U-shaped damper. The energy allocated to the U-shaped damper, The number of U-shaped dampers installed on a single composite shock absorber. This represents the maximum stroke of the U-shaped damper. The damping coefficient of the U-shaped damper. For the compression rate of the U-shaped damper, The stiffness of the U-shaped damper.

[0030] Compared with the prior art, the present invention has the following advantages:

[0031] This invention utilizes a tiered combination of "high-damping rubber pads - composite shock absorbers - impact-resistant steel plates" to dissipate impact energy step by step, preventing brittle failure of the dam body and significantly improving the dam's resistance and energy dissipation effect against large rock impacts, thereby enhancing structural safety and durability. The composite shock absorber employs a combination of a disc-shaped composite material layer, a spring layer, and a vertical compression spring, combining flexible energy dissipation with strong vertical support to achieve tiered energy absorption and efficient buffering. The U-shaped damper arrangement enhances energy dissipation capacity and limits relative displacement, effectively controlling instantaneous stress peaks. Attached Figure Description

[0032] Figure 1 This is a schematic diagram of the overall structure of Embodiment 1 of the present invention;

[0033] Figure 2 This is a partial connection diagram of Embodiment 1 of the present invention;

[0034] Figure 3 This is a schematic diagram of the overall structure of Embodiment 2 of the present invention;

[0035] Figure 4 This is a partial connection diagram of Embodiment 2 of the present invention;

[0036] Attached reference numerals: 1. Dam body; 2. High-damping rubber pad; 3. Composite damper; 31. Composite damping unit; 311. Composite material layer; 312. Disc spring layer; 313. Dividing steel plate; 314. Central compression spring; 315. Fine compression spring; 32. Top plate; 33. Bottom plate; 34. Rubber protective layer; 4. Impact-resistant steel plate; 5. U-shaped damper; 6. Anchor bolt; 7. Bolt. Detailed Implementation

[0037] To make the objectives, technical solutions, and advantages of this invention clearer, the invention will be further described in detail below with reference to the accompanying drawings and specific embodiments.

[0038] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some, not all, of the embodiments of the present invention. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0039] Example 1:

[0040] like Figure 1 and Figure 2 As shown, a composite vibration damping and energy dissipation structure for debris flow retaining dams to prevent impact from large rocks includes a dam body 1, a high-damping rubber pad 2, composite dampers 3, U-shaped dampers 5, and an impact-resistant steel plate 4. The high-damping rubber pad 2 is made of polymer damping material and is tightly attached to the surface of the dam body 1. Several composite dampers 3 are installed on the high-damping rubber pad 2, and the impact-resistant steel plate 4 is laid on top of the composite dampers 3.

[0041] The composite damper 3 includes a composite damping unit 31, a base plate 33, and a top plate 32. The composite damping unit 31 is cylindrical, with its bottom and top connected to the base plate 33 and the top plate 32, respectively. Several U-shaped dampers 5 are evenly distributed on the outer circumference of the composite damping unit 31. The upper side plate of the U-shaped damper 5 is fixedly connected to the top plate 32 and the impact-resistant steel plate 4 by bolts 7. Anchor bolts 6 are pre-embedded on the inclined surface of the dam body 1. The lower side plate of the U-shaped damper 5 is fixedly connected to the base plate 33 and the high-damping rubber pad 2 by anchor bolts 6 and nuts.

[0042] The composite damping unit 31 consists of a composite material layer 311, a partition steel plate 313, a disc spring layer 312, and a central compression spring 314. The composite material layer 311, the partition steel plate 313, and the disc spring layer 312 are each provided with several layers. The composite material layer 311 and the disc spring layer 312 are stacked alternately, and the partition steel plate 313 separates the composite material layer 311 and the disc spring layer 312. The central compression spring 314 passes through the center of the composite material layer 311, the partition steel plate 313, and the disc spring layer 312, and its two ends are fixedly connected to the top plate 32 and the bottom plate 33, respectively.

[0043] Among them, the disc spring layer 312 is a disc spring group, which is composed of multiple large disc springs arranged longitudinally. The outer diameter of the large disc springs is consistent with the outer diameter of the composite damping unit 31, and the central compression spring passes through the central hole of the large disc spring.

[0044] Among them, the outer circumference of the composite damping unit 31 is also wrapped with a rubber protective layer 34.

[0045] Example 2:

[0046] like Figure 3 and Figure 4 As shown, a composite vibration damping and energy dissipation structure for debris flow retaining dams to prevent impact from large rocks includes a dam body 1, a high-damping rubber pad 2, composite shock absorbers 3, and an impact-resistant steel plate 4. The high-damping rubber pad 2 is made of polymer damping material and is tightly attached to the surface of the dam body 1. Several composite shock absorbers 3 are installed on the high-damping rubber pad 2, and the impact-resistant steel plate 4 is laid on top of the composite shock absorbers 3.

[0047] The composite damper 3 includes a composite damping unit 31, a base plate 33, and a top plate 32. The composite damping unit 31 is cylindrical, with its bottom and top connected to the base plate 33 and the top plate 32, respectively. The top plate 32 is fixedly connected to the impact-resistant steel plate 4 by bolts 7. Anchor bolts 6 are pre-embedded on the inclined surface of the dam body 1. The base plate 33 is fixedly connected to the high-damping rubber pad 2 by anchor bolts 6 and nuts.

[0048] The composite damping unit 31 consists of a composite material layer 311, a partition steel plate 313, a disc spring layer 312, a central compression spring 314, and a fine compression spring 315. The composite material layer 311, the partition steel plate 313, and the disc spring layer 312 are each provided with several layers. The composite material layer 311 and the disc spring layer 312 are stacked alternately, and the partition steel plate 313 separates the composite material layer 311 and the disc spring layer 312. The central compression spring 314 passes through the center of the composite material layer 311, the partition steel plate 313, and the disc spring layer 312, and its two ends are fixedly connected to the top plate 32 and the bottom plate 33, respectively.

[0049] The disc spring layer 312 consists of several disc spring groups arranged horizontally in a circular array. Each disc spring group is composed of several small disc springs arranged vertically, and the outer diameter of the small disc springs is smaller than the radius of the composite damping unit 31. The number of fine compression springs 315 is the same as the number of disc spring groups in the disc spring layer 312. The fine compression springs 315 penetrate the composite material layer 311, the disc spring layer 312, and the partition steel plate 313, and their two ends are connected to the top plate 32 and the bottom plate 33, respectively. The fine compression springs 315 pass through the holes in the disc spring groups in the disc spring layer 312.

[0050] Among them, the outer circumference of the composite damping unit 31 is also wrapped with a rubber protective layer 34.

[0051] The working principle of this invention is as follows: When a debris flow carrying large rocks impacts a retaining dam, the impact energy is transmitted and dissipated sequentially. Specifically, the impact-resistant steel plate 4 bears and disperses the initial impact energy, the partition steel plate 313 and the central compression spring 314 inside the composite shock absorber 3 provide rigid support, the disc spring layer 312 and the composite material layer 311 absorb energy through deformation, the disc spring layer 312 and the compression spring work together to buffer the impact in stages, the U-shaped damper 5 generates additional damping force, and the high-damping rubber pad 2 further reduces the remaining impact energy, preventing brittle failure of the dam body 1 and improving the safety and service life of the debris flow retaining dam.

[0052] A design method for a composite vibration-damping and energy-dissipating structure for debris flow retaining dams to withstand the impact of large boulders, the method comprising the following steps:

[0053] S1. Based on historical debris flow data of the debris flow gully, the debris flow impact energy is roughly calculated. A safety margin is then introduced to further determine the design energy of the composite vibration reduction and energy dissipation structure of the retaining dam. The formula for calculating the debris flow impact energy is:

[0054] ;

[0055] The design energy of the composite vibration reduction and energy dissipation structure of the retaining dam is:

[0056] ;

[0057] in, The first in the mudslide The quality of the stone block For the first The speed of the stone blocks The instantaneous impact pressure of the mudflow. Let be a function of mudflow velocity as a function of time. This represents the total number of rocks in the debris flow. The design energy of the composite vibration reduction and energy dissipation structure for retaining dams. For safety margin, This refers to the impact energy of a debris flow.

[0058] S2. The design energy of the composite vibration reduction and energy dissipation structure of the retaining dam is weighted and distributed to the high-damping rubber pad, composite damper and U-shaped damper. The energy absorption formulas of the high-damping rubber pad, composite damper and U-shaped damper are determined by force analysis. The structural parameters are initially designed according to the energy absorption formulas of each part and the energy distribution.

[0059] The energy absorption formula for the high-damping rubber pad is as follows:

[0060] ;

[0061] in, To distribute the energy to the high-damping rubber pad, The equivalent stiffness of the high-damping rubber pad. The thickness of the high-damping rubber pad, The compression ratio of the high-damping rubber pad material;

[0062] The energy absorption formula for the composite shock absorber is as follows:

[0063] ; ;

[0064] in, The energy borne by a single composite shock absorber The number of composite shock absorbers, The energy allocated to the composite shock absorber, The number of layers in the composite layer and disc spring layer. For the first The equivalent stiffness of the composite material layers in the layered composite structure, For the first The deformation of the composite material layer in the layered composite structure. For the first The stiffness of the disc spring layer in the layered composite structure. For the first The compression of the disc spring layer in the layered composite layer;

[0065] The energy absorption formula for the U-shaped damper is as follows:

[0066] ; ;

[0067] in, The energy borne by a single U-shaped damper. The energy allocated to the U-shaped damper, The number of U-shaped dampers installed on a single composite shock absorber. This represents the maximum stroke of the U-shaped damper. The damping coefficient of the U-shaped damper. For the compression rate of the U-shaped damper, The stiffness of the U-shaped damper.

[0068] S3. Establish a finite element model of the composite vibration reduction and energy dissipation structure of the debris flow barrier dam, apply debris flow impact load, and analyze the stress, deformation and energy distribution of each layer; adjust the structural parameters of the high-damping rubber pad, composite damper and U-shaped damper to make the instantaneous stress peak less than the allowable stress; and verify the structural recovery ability after multiple impacts to ensure that the structure can be reused.

[0069] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions, and improvements made within the spirit and principles of the present invention should be included within the protection scope of the present invention.

Claims

1. A design method for a composite vibration reduction and energy dissipation structure for debris flow retaining dams designed to withstand the impact of large boulders, characterized in that, The composite vibration damping and energy dissipation structure of the debris flow barrier dam for preventing large rock impacts includes a dam body, a high-damping rubber pad, composite shock absorbers, and impact-resistant steel plates. The high-damping rubber pad is laid on the sloping surface of the dam body, and several composite shock absorbers are arranged on the surface of the high-damping rubber pad. The impact-resistant steel plates are laid on top of the composite shock absorbers. The composite shock absorber includes a composite damping unit, a bottom plate, and a top plate. The top plate and bottom plate are respectively located at the top and bottom of the composite damping unit, and the top plate and bottom plate are respectively connected to the impact-resistant steel plates and the high-damping rubber pad. The damping rubber pads are fixedly connected. Several U-shaped dampers are evenly arranged on the outer circumference of the composite damping unit. The upper and lower side plates of the U-shaped dampers are respectively connected to the top plate and the bottom plate. The composite damping unit includes several composite material layers, several disc spring layers, several partition steel plates and a central compression spring. The composite material layers and disc spring layers are alternately stacked and separated by the partition steel plates. The central compression spring passes through the center of the composite material layers, disc spring layers and partition steel plates, and its two ends are fixedly connected to the top plate and the bottom plate respectively. The design methodology includes the following steps: S1. Based on historical debris flow data of the debris flow gully, the debris flow impact energy is roughly calculated, and a safety margin is introduced to further determine the design energy of the composite vibration reduction and energy dissipation structure of the retaining dam; the formula for calculating the debris flow impact energy is: ； The design energy of the composite vibration reduction and energy dissipation structure of the retaining dam is: ； in, The first in the mudslide The quality of the stone block For the first The speed of the stone blocks The instantaneous impact pressure of the mudflow. Let be a function of mudflow velocity as a function of time. This represents the total number of rocks in the debris flow. The design energy of the composite vibration reduction and energy dissipation structure for retaining dams. For safety margin, This refers to the impact energy of a debris flow. S2. The design energy of the composite vibration reduction and energy dissipation structure of the retaining dam is weighted and distributed to the high-damping rubber pad, composite damper and U-shaped damper. The energy absorption formulas of the high-damping rubber pad, composite damper and U-shaped damper are determined by force analysis. The structural parameters are initially designed according to the energy absorption formulas of each part and the energy distribution. S3. Establish a finite element model of the composite vibration reduction and energy dissipation structure of the debris flow barrier dam, apply debris flow impact load, and analyze the stress, deformation and energy distribution of each layer; adjust the structural parameters of the high-damping rubber pad, composite damper and U-shaped damper to make the instantaneous stress peak less than the allowable stress; and verify the structural recovery ability after multiple impacts to ensure that the structure can be reused.

2. The design method for the composite vibration reduction and energy dissipation structure of debris flow retaining dams according to claim 1, characterized in that, The disc spring layer is a disc spring group composed of several large disc springs arranged longitudinally. The outer diameter of the large disc spring is the same as the outer diameter of the composite damping unit, and the central compression spring passes through the central hole of the large disc spring.

3. The design method for the composite vibration reduction and energy dissipation structure of debris flow retaining dams according to claim 1, characterized in that, The disc spring layer includes several disc spring groups, which are arranged horizontally in a circular array. Each disc spring group is composed of several small disc springs arranged longitudinally, and the outer diameter of each small disc spring is smaller than the radius of the composite damping unit.

4. The design method for the composite vibration reduction and energy dissipation structure of debris flow retaining dams according to claim 3, characterized in that, The composite damping unit also includes several fine compression springs, which pass through the central hole of the disc spring assembly and are fixedly connected at both ends to the top plate and the bottom plate, respectively.

5. The design method for the composite vibration reduction and energy dissipation structure of the debris flow retaining dam according to claim 1, characterized in that, The upper side plate, top plate, and impact-resistant steel plate of the U-shaped damper are fixedly connected by bolts; anchor bolts are pre-embedded on the inclined surface of the dam body, and the lower side plate, bottom plate, and high-damping rubber pad of the U-shaped damper are fixedly connected by the anchor bolts and nuts.

6. The design method for the composite vibration reduction and energy dissipation structure of the debris flow retaining dam according to claim 1, characterized in that, The outer circumference of the composite damping unit is wrapped with a rubber protective layer.

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