Self-floating pier anti-icing device and preparation method thereof

Abstract

This invention discloses a self-floating bridge pier anti-icing impact device and its manufacturing method. The device includes a casing body, which is composed of ice-breaking and flow-guiding segments, a middle segment, and a tail segment arranged longitudinally. The ice-breaking and flow-guiding segments are connected to the middle segment by an elastic connecting element with a preset critical trigger threshold. When the impact force exceeds the threshold, the elastic connecting element compresses and absorbs energy, and drives the ice-breaking and flow-guiding segments to automatically reset after the impact force is removed. The casing body is filled with energy-absorbing material. The manufacturing method is used to manufacture this self-floating bridge pier anti-icing impact device. This invention achieves sequential active protection with a "rigid first, flexible later" approach through the elastic connecting reset element, balancing efficient ice breaking and strong impact buffering. It also has automatic reset and adaptive water level change capabilities, significantly improving the ice impact resistance safety and life-cycle economy of bridges in cold regions.

Description

Technical Field

[0001] This invention relates to the field of bridge anti-collision technology, specifically to a self-floating bridge pier anti-icing device and its preparation method. Background Technology

[0002] Bridge construction is increasingly common on waterways in cold regions such as the Yellow River, Liao River, Songhua River, and Heilongjiang River. However, bridges located in cold regions are often severely threatened by drifting ice floes in spring. The direct impact of drifting ice on bridge piers can not only cause damage such as cracking and spalling of the piers themselves, but also cause disturbance and vibration of the bridge superstructure, seriously affecting traffic safety and structural durability.

[0003] To enhance the resistance of bridge piers to ice floe impacts, existing technologies typically involve installing icebreakers or anti-collision devices on the ice-facing side of the piers. Currently, common icebreakers are primarily pointed or curved solid structures made of high-strength reinforced concrete or concrete encased in steel plates. While these fixed icebreakers can resist ice floe impacts to some extent, they lack self-adjusting capabilities. In areas with significant variations in river water levels, especially for flexible high-pier bridges, using such solid icebreakers would require constructing structures tens of meters high, which is economically impractical. Furthermore, the large slenderness ratio of flexible high piers means that direct impacts from ice floes can cause significant displacement of the pier top, seriously threatening the structural safety of the bridge.

[0004] In recent years, self-floating anti-collision devices have emerged, which can automatically rise and fall with changes in water level, making them suitable for rivers with large water level fluctuations. However, existing self-floating anti-collision devices are mostly designed for ship collisions and are difficult to adapt to cold-region environments. The few devices designed for ice collisions generally adopt rigid or only-flexible structural forms: either the overall rigidity is too high, resulting in good ice-breaking performance but the impact force is directly transmitted to the bridge piers, failing to effectively buffer the impact; or the overall flexibility is too high, which, while absorbing impact energy, results in low ice-breaking efficiency, and large ice floes cannot be effectively broken up and diverted. Furthermore, existing devices often fail to automatically reset after impact due to accumulated plastic deformation and structural jamming, leading to a gradual decrease in protective capability, or even complete failure, requiring frequent replacements and incurring high life-cycle costs. More critically, existing technologies lack an ice-collision protection device that can actively switch between "rigid support" and "flexible energy dissipation" operating modes based on the magnitude of the ice floe impact force, failing to achieve time-controlled protection that is "rigid during ice breaking and flexible during buffering." Summary of the Invention

[0005] To address the shortcomings of existing technologies, the technical problem to be solved by this invention is to provide a self-floating bridge pier anti-icing device that can efficiently break up flowing ice, effectively buffer impact energy, automatically reset after impact, and has the ability to adapt to changes in water level.

[0006] To achieve the above objectives, the present invention provides the following technical solution: a self-floating bridge pier anti-icing collision device and its preparation method, comprising: The system includes a main casing that is fitted around the connecting pier. The main casing includes an ice-breaking guide segment, a middle segment, and a tail segment arranged longitudinally. The ice-breaking guide segment and the middle segment are connected by an elastic connecting element. The elastic connecting element has a preset critical trigger threshold, which is used to compress to absorb energy when the impact force exceeds the threshold and drive the ice-breaking guide segment to reset after the impact force is removed. The main casing is filled with energy-absorbing material.

[0007] Furthermore, the ice-breaking guide segment has a guide surface with a dual-angle composite geometry design, wherein the guide surface has an included angle of 70° to 110° in the horizontal plane to induce brittle fracture of the ice; and the guide surface has an inclination angle of 60° to 85° in the vertical direction to induce bending fracture of the ice.

[0008] Furthermore, the elastic connection recovery component includes a connecting rod and a self-resetting element. The self-resetting element is a pre-compression spring array, which is disposed within a mounting hole in the middle segment. The connecting rod is slidably inserted into the mounting hole, and one end of the connecting rod is fixedly connected to the ice-breaking guide segment, while the other end is connected to the pre-compression spring array. The pre-compression spring array has a preset critical trigger threshold, which is determined based on the critical reaction force required for the ice floe in the target river section to bend and break. Furthermore, the stiffness coefficient k of the pre-compression spring array satisfies both the upper limit constraint of the reaction force and the lower limit constraint of the energy. The upper limit constraint of the reaction force: at the extreme compression stroke S max The total reaction force F below max Less than the allowable bearing capacity threshold P of the bridge pier, i.e. Where F0 is the critical trigger threshold; The energy lower limit constraint: Under the extreme impact kinetic energy of the target, the compression stroke of the spring is not exhausted.

[0009] Furthermore, it also includes a U-shaped energy-consuming element and a limiting rod; the U-shaped energy-consuming element is disposed between the inner wall of the main body of the casing and the pier; one end of the limiting rod is fixed to the middle segment, and the other end can slide into the positioning hole of the ice-breaking and guiding segment to constrain its lateral and vertical offset.

[0010] Furthermore, the outer shell of the main body of the casing is covered with an anti-compression buffer layer, which is a honeycomb hollow tubular buffer pad made of polymer rubber. Each hollow tubular unit has a sealing end face at both ends of the axial direction, forming an independent closed cavity.

[0011] Furthermore, the energy-absorbing filler material is a superhydrophobic porous cement-based composite material, the apparent density of which is adjustable, and the internal pore walls of which possess hydrophobic properties.

[0012] Furthermore, the system also includes a flexible waterproof fabric, which forms a dynamic seal at the longitudinal displacement gap between the ice-breaking guide segment and the middle segment.

[0013] A method for preparing a self-floating bridge pier anti-icing device based on the above includes the following steps: Step 1: Prepare the outer shell of the ice-breaking guide segment, the middle segment shell, and the tail segment shell with a preset geometry; Step 2: Prepare materials with an apparent density of 200–1000 kg / m³ 3 A continuously tunable superhydrophobic porous cement-based composite material within a certain range, used as an energy-absorbing filler material; Step 3: Based on the protection water level range and hydrological data of the target bridge, determine the design draft and stability requirements of the device, and determine the density distribution scheme of the energy-absorbing filling material in different areas inside the device through parametric iterative calculation. Step 4: According to the density distribution scheme, fill the corresponding chambers of the middle segment and the tail segment with energy-absorbing filling materials of different apparent densities respectively; Step 5: Connect the ice-breaking guide segment and the middle segment through the elastic connection restorer, assemble the middle segment and the tail segment through the connecting flange, and apply pre-pressure to the elastic connection restorer of the middle segment to set its critical trigger threshold. Step 6: Wrap and fix a compression-resistant buffer layer made of polymer rubber with a closed cavity on the outside of the outer shell.

[0014] Furthermore, the method for preparing superhydrophobic porous cement-based composite materials in step two includes: controlling its apparent density by adjusting the amount of foaming agent, and adding a hydrophobic agent to make the surface contact angle of the internal pore walls greater than 120°.

[0015] Furthermore, the method for determining the density distribution scheme in step three includes an active center of gravity control method using a mass moment balance compensation method and a parameterized linkage iterative algorithm. By filling the filling chambers on the ice-facing side and the ice-repelling side with energy-absorbing filling materials of different densities, a reverse mass moment is constructed to counteract the initial eccentric moment, so that the center of gravity projection of the device is located near the centroid of the waterline.

[0016] The beneficial effects of this invention are: The aforementioned self-floating bridge pier anti-icing device has at least the following advantages: 1) Adopting a "rigid first, flexible later" sequential active protection approach, balancing icebreaking efficiency and buffering performance. This invention, by setting an elastic connecting element with a preset critical trigger threshold between the ice-breaking and guiding segment and the middle segment, achieves for the first time active timing control of the mechanical response mode of the anti-collision device. Specifically: When encountering conventional ice flow impact (impact force below the threshold), the elastic connection restorer provides rigid support, making the ice-breaking and guiding segment equivalent to a rigid body, ensuring that it can effectively cut into the ice to complete the breaking and guiding action, thereby reducing the direct impact force of ice flow on the bridge pier from the source. When encountering extremely thick ice or large drifting objects (impact force exceeding the threshold), the system automatically switches to a flexible energy dissipation mode. The elastic connecting components undergo controllable compression, absorbing and buffering most of the impact kinetic energy, significantly extending the impact time, thereby effectively reducing the peak load transmitted to the bridge pier.

[0017] Compared to the single-mode design of existing technologies that are either fully rigid or fully flexible, this device achieves the organic unity and seamless switching of ice-breaking and buffering functions, ensuring efficient ice breaking under normal working conditions and providing reliable safety redundancy for extreme working conditions.

[0018] (2) It has automatic reset capability, enabling the device to be used cyclically. In this invention, the elastic connection recovery component can immediately release its stored elastic potential energy (including initial pre-compression potential energy and impact-added potential energy) after the impact force is removed, driving the ice-breaking guide segment to automatically return to its initial extended position, preparing for the next impact. This self-resetting characteristic transforms the anti-collision device from a traditional disposable "consumable facility" into a "recoverable asset" that can be used cyclically for a long time, significantly reducing the maintenance frequency and replacement cost of the device.

[0019] (3) Adaptive floating state is achieved through internal filling material to adapt to large changes in water level. This invention fills the interior of the casing with an energy-absorbing material. This material not only provides additional structural support and energy dissipation capacity, but more importantly, its adjustable density characteristics enable precise regulation of the overall buoyancy and stability of the device. The device can automatically adjust its draft according to the rise and fall of the river water level, always keeping the ice-breaking guide section at the optimal ice-facing height. It is particularly suitable for cold-region rivers with large water level fluctuations, solving the technical problems of limited protection range of fixed icebreakers and difficulty in controlling the buoyancy of self-floating devices.

[0020] (4) Improve bridge safety and life-cycle economy Through the integrated design of "rigid ice-breaking, flexible impact absorption, automatic reset, and adaptive floating state," this device effectively reduces the peak ice impact force, buffers impact energy, maintains structural integrity and protective functions, and significantly improves the safety and durability of bridge piers and superstructures in complex cold environments. Meanwhile, the modular, flexible connection design and automatic reset capability allow the device to withstand multiple repeated impacts without requiring complete replacement, resulting in a significantly lower life-cycle cost compared to existing disposable or easily damaged anti-collision devices. Attached Figure Description

[0021] To more clearly illustrate the specific embodiments of the present invention, the accompanying drawings used in the specific embodiments will be briefly described below. In all the drawings, the elements or parts are not necessarily drawn to scale.

[0022] Figure 1 This is a schematic diagram of a self-floating bridge pier anti-icing device according to an embodiment of the present invention; Figure 2 for Figure 1 The diagram shows the internal structure of the self-floating bridge pier anti-icing device. Figure 3 for Figure 1 Three-view diagram of the ice guide section of the self-floating bridge pier anti-icing device shown; Figure 4 for Figure 1 The diagram shows the multi-stage impact energy dissipation and automatic timing reset function of the self-floating bridge pier anti-icing device. Figure 5 for Figure 1 The working principle of the anti-compression buffer layer in the self-floating bridge pier anti-icing impact device shown; Figure 6 for Figure 1 The diagram shows the energy absorption principle of porous cement-based composite material in the self-floating bridge pier anti-icing device. Figure 7 This is a schematic diagram illustrating the vertical center of gravity adjustment principle in a method for preparing a self-floating bridge pier anti-icing collision device according to an embodiment of the present invention. Figure 8 This is a schematic diagram illustrating the horizontal center control principle in the preparation method of the self-floating bridge pier anti-icing device according to an embodiment of the present invention. Figure 9 This is a schematic diagram of a method for preparing a self-floating bridge pier anti-icing collision device according to an embodiment of the present invention; Figure label: 1. Ice guide segment; 2. Middle segment; 3. Tail segment; 4. Elastic connection restorer; 41. Connecting rod; 42. Self-resetting element; 5. U-shaped energy dissipation element; 6. Limiting rod; 7. Anti-compression buffer layer; 8. Energy-absorbing filling material; 9. Waterproof cloth. Detailed Implementation

[0023] To make the above-mentioned objects, features, and advantages of the present invention more apparent and understandable, specific embodiments of the present invention will be described in detail below with reference to the accompanying drawings. Many specific details are set forth in the following description to provide a thorough understanding of the present invention. However, the present invention can be practiced in many other ways different from those described herein, and those skilled in the art can make similar modifications without departing from the spirit of the invention; therefore, the invention is not limited to the specific embodiments disclosed below.

[0024] Please see Figures 1 to 2 This invention provides a self-floating bridge pier anti-icing device, mainly comprising a box-shaped main body. This box-shaped main body is fitted around the connecting bridge pier. Longitudinally (i.e., in the direction of water flow or from the pier's ice-facing side to the ice-repellent side), the box-shaped main body is composed of an ice-breaking and flow-guiding segment 1, a middle segment 2, and a tail segment 3. The middle segment 2 is the main structure, forming an internal cavity and providing the main buoyancy. The ice-breaking and flow-guiding segment 1 is located at the foremost end and is the core component that directly contacts the flowing ice and performs ice-breaking and flow-guiding functions. The tail segment 3 is located at the rear end.

[0025] The ice-breaking guide segment 1 and the middle segment 2 are not rigidly fixed, but are connected by an elastic connecting element. This elastic connecting element has a preset critical trigger threshold F0. Its operation consists of two stages: Rigid support stage (rigid icebreaking response before threshold triggering): When the impact force of the flowing ice is less than or equal to the critical threshold F0, the elastic connecting restorer maintains its initial compressed state, providing an approximately rigid support reaction force for the icebreaking guide segment 1. At this time, the entire icebreaking guide segment 1 is structurally equivalent to a rigid body, ensuring that it can effectively cut into the ice and complete the icebreaking action. This mechanism achieves active control over when the structure is rigid and when it is flexible by manually setting the structural response threshold.

[0026] Flexible energy dissipation and reset phase (stiffness-controlled flexible energy dissipation buffer): When the impact force exceeds the threshold F0 (e.g., encountering extremely thick ice or large drifting objects), the elastic connecting component undergoes controlled compression, absorbing and buffering most of the impact kinetic energy, significantly prolonging the impact duration, thereby reducing the peak load transmitted to the pier. After the impact force is removed, the elastic connecting component immediately releases its stored elastic potential energy (including initial pre-compression potential energy and impact-added potential energy), driving the ice-breaking guide segment 1 to automatically return to its initial extended position, preparing for the next impact.

[0027] The internal cavities of the ice-breaking and flow-guiding section 1, the middle section 2, and the tail section 3 (⑦) of the main body of the casing are filled with energy-absorbing filling material 8. This energy-absorbing filling material 8 provides structural support and additional energy dissipation capacity on the one hand, and achieves precise adjustment of the overall buoyancy and stability of the device on the other hand through its adjustable density.

[0028] This embodiment, by setting an elastic connection recovery component with a preset critical threshold, achieves for the first time active control over when a bridge anti-collision device is rigid and when it is flexible. Compared with the existing technology's approach of either being entirely rigid (which easily leads to damage to bridge piers) or entirely flexible (which has low ice-breaking efficiency), this device takes into account both the requirements of efficient ice breaking and strong impact buffering, and has automatic reset capability, allowing for cyclic service and significantly improving the device's overall life-cycle economy and protective reliability.

[0029] Please see Figure 3 To improve ice-breaking efficiency, the geometry of the ice-breaking guide segment 1 was specially designed in this embodiment. This segment features a guide surface with a dual-angle composite geometry design: The included angle α in the horizontal plane: The included angle α of the guiding surface in the horizontal plane is preferably 70° to 110° (for example, 90° for typical ice conditions in the Inner Mongolia section of the Yellow River). This angle causes significant local stress concentration near the contact point when the ice floes collide, prompting the ice to quickly reach its tensile or bending strength limit, thereby initiating and propagating brittle cracks and achieving the initial breakage of the ice.

[0030] Vertical inclination angle φ: The vertical inclination angle φ of the guiding surface is preferably 60° to 85° (for example, 75° for the Songhua River basin where the ice thickness is large). This angle causes the advancing ice floe to experience an upward normal component force as it slides along the slope, generating a lifting moment. This moment couples with the gravitational bending moment of the ice body itself, significantly increasing the bending stress of the ice floe, causing large-scale bending fractures of the ice body, and breaking the large ice floe into fragments.

[0031] When ice floes impact, the dual-angle guiding surfaces work synergistically: the horizontal angle induces shear fracture (brittle fracture), and the vertical angle induces bending fracture. The kinetic energy of the broken ice is significantly dissipated due to internal friction and the formation of fracture surfaces, and is guided along the inclined guiding surfaces to flow towards both sides of the bridge pier. This effectively changes the original direction of movement and impact vector of the ice floe, thereby reducing the linear momentum and impulse directly transmitted to the bridge pier from the source. This process achieves dual regulation of energy and path from "impact-breaking-guiding". To ensure that the ice-breaking guiding segment 1 effectively breaks ice and guides flow without being easily deformed by the impact of the ice floe, its stiffness should be set greater than the stiffness of the ice floe (this data should be determined based on the extreme thickness of ice floes during the ice jam season in the relevant region).

[0032] This dual-angle design is not a simple geometric combination, but a "shear-bending" composite ice-breaking mechanism based on ice fracture mechanics. Compared with existing single-angled or arc-shaped icebreakers, this embodiment has higher ice-breaking efficiency, can decompose large-volume ice floes into harmless ice fragments, and simultaneously achieves a flow guiding function, effectively reducing the burden on subsequent energy dissipation systems.

[0033] In this embodiment, the elastic connection restorer 4 includes a force-transmitting connecting rod 41 and a self-resetting element 42. The self-resetting element 42 is a pre-compressed spring array, which is disposed in a dedicated mounting hole inside the middle segment 2. One end of the force-transmitting connecting rod 41 is fixedly connected to the rear end face of the ice-breaking guide segment 1, and the other end is slidably inserted into the mounting hole and connected to the pre-compressed spring array.

[0034] Threshold setting and stiffness design: The preset critical triggering threshold F0 of the preloaded spring array is not an empirical value, but is quantitatively determined based on the critical reaction force required for the ice floes in the target river section to bend and break. This critical reaction force is calculated by investigating the ultimate thickness of the ice floes and the bending strength of the ice during the local ice jam season, ensuring that only a force capable of causing the ice to fracture can trigger spring compression. To cope with extreme ice conditions, the stiffness coefficient k of the preloaded spring array must meet the following dual constraints, forming the "pier bearing capacity inversion method" design system: First constraint: Upper limit constraint of reaction force (ensuring the safety of the bridge pier), the spring at its limit compression stroke S max The total reaction force F at that time max It must be strictly less than the allowable bearing capacity threshold P of the bridge pier under ice impact conditions, that is, it must satisfy: F0 is the critical trigger threshold; this formula ensures that even when the spring is compressed to its limit due to the most extreme impact, the force transmitted to the pier will not exceed its structural safety limit, thus preventing damage to the pier.

[0035] The second constraint: energy lower limit constraint (to prevent rigid impact), must ensure that the spring system can withstand the extreme impact kinetic energy E at design limits. k Under input, its compression stroke is sufficient to absorb the energy, avoiding "rigid bottoming" damage to the structure due to stroke exhaustion.

[0036] By solving the above mechanical models simultaneously, the optimal range of spring stiffness values ​​can be determined.

[0037] During operation, when the ice impact force F < F0, the spring does not compress further, providing rigid support. When F ≥ F0, the system switches from the preset rigid ice-breaking mode to a flexible energy-dissipating mode, the spring begins to compress, and the impact kinetic energy is converted into spring potential energy. After the impact ends, the spring potential energy is released, driving the ice-breaking head to reset.

[0038] By correlating the critical reaction force required for ice breaking with the preload threshold of the spring and employing a precise stiffness matching formula, this embodiment achieves seamless switching between ice breaking and buffering functions. This quantitative design method based on a mechanical model is not available in existing crash protection devices designed based on experience, greatly improving the reliability and predictability of protection.

[0039] To achieve multi-path dissipation of impact energy and precise reset under eccentric impact, this embodiment also integrates a U-shaped energy dissipation element 5 and a limiting rod 6.

[0040] The U-shaped energy-dissipating element 5, made of high-polymer rubber, is disposed between the inner wall of the cofferdam body and the outer wall of the pier. During an impact, the entire cofferdam shifts relative to the pier, and the U-shaped energy-dissipating element 5 deforms under the combined action of shear and compression (the U-shaped structure provides a larger deformation stroke). Its viscoelastic properties can convert some of the impact energy into heat energy for dissipation. In addition, under normal conditions, this energy-dissipating element also serves as a flexible isolation element, reducing direct contact and wear between the cofferdam and the pier.

[0041] One end of the limiting rod 6 is fixed to the front end face of the middle segment 2, and the other end can slide into the positioning hole opened on the rear end face of the ice-breaking guide segment 1. A small gap is left between the positioning hole and the limiting rod 6, which allows longitudinal sliding but strictly restricts the relative movement of the lateral and vertical directions.

[0042] The system utilizes a synergistic energy dissipation mechanism, combining a self-resetting element 42 as the main energy storage unit with a U-shaped element as a secondary energy dissipation unit. The spring is responsible for storing and releasing the main kinetic energy, while the U-shaped element serves as a supplement, attenuating the peak impact force and reducing direct wear between the caisson and the pier.

[0043] When ice flows obliquely impact an iceberg, the impact force generates a torsional moment, which can easily cause the icebreaker head to twist or shift and jam during resetting. At this point, the cooperation between the limit rod 6 and the positioning hole plays a crucial guiding role. The rod converts the eccentric load into a lateral guiding force on the hole wall, forcing the icebreaker head to retract in a straight line. Combined with the elastic restoring force of the U-shaped energy-dissipating element 5 during unloading, the three elements work together to achieve anti-jamming, high-precision, and automated resetting of the icebreaker head under any eccentric condition. For the principle of the automated resetting mechanism, please refer to [link to relevant documentation]. Figure 4 To address the static expansion pressure of ice layers unique to cold regions, this embodiment incorporates a dedicated anti-compression buffer layer 7 covering the outer shell of the main body of the casing. Its working principle is described in [link to documentation]. Figure 5 The buffer layer is a honeycomb hollow tubular buffer pad made of polymer rubber. Its key innovation lies in the fact that each hollow tubular unit has a sealing end face at both ends of the axial direction, forming an independent closed cavity, thus constructing a rigid-flexible coupling protection system between the compression-resistant buffer layer 7 (outer flexible deformation layer) and the outer casing (inner rigid support layer).

[0044] The sealed cavity fundamentally prevents water (and subsequent ice and sediment) from intruding into the interior. This sealed structure is not simply a waterproofing measure, but a targeted design against the failure chain of "water intrusion → freezing expansion → loss of compressible space → structural failure" in cold regions. This avoids the "freezing blockage failure" caused by water ingress and freezing in cold regions—that is, the cavity is filled with ice, losing compressible space, and even cracking due to the expansion of ice.

[0045] Quasi-static energy absorption (displacement compensation and stress attenuation): When the surrounding ice expands due to temperature drop, exerting continuous and large-area static compression on the device, the honeycomb hollow tube undergoes quasi-static progressive collapse. This process produces two effects: 1) Displacement compensation effect: The compression of the buffer layer provides space for the expansion of the ice layer, fundamentally reducing the huge compressive potential energy generated by completely constraining the expansion of the ice layer; 2) Stress attenuation and redistribution: The extremely high concentrated compressive stress that originally acted directly on the rigid shell is attenuated through the buckling and flattening process of the hollow unit and transformed into a large-area distributed compressive load on the flexible structure.

[0046] Synergistic load-bearing through internal and external rigid-flexible coupling: The internal alloy steel outer shell is not a passive isolation layer, but rather a rigid load-bearing boundary serving as the anti-compression buffer layer 7. When the outer buffer layer collapses under pressure, the outer shell provides it with a solid normal support reaction force, ensuring that the buffer layer is fully compressed and absorbs energy radially, rather than undergoing ineffective penetrating collapse into the device. At the same time, the outer shell constitutes a second rigid line of defense against high-energy impacts.

[0047] To simultaneously address the three major issues of floating state regulation, freeze-thaw durability, and extreme energy consumption, the energy-absorbing filler material 8 in this embodiment is a superhydrophobic porous cement-based composite material. A schematic diagram of its energy absorption principle can be found here. Figure 6 This material possesses the following cross-scale design features, undertaking the triple core functions of floating state control, durability assurance, and extreme safety redundancy: Density adjustable (floating state and stability control): By adjusting the amount of foaming agent, its apparent density can be adjusted from 200 to 1000 kg / m³. 3 Continuous and precise control within a given range provides key variable parameters for floating design. Utilizing the controllable density characteristics of porous cement-based materials, this device achieves optimization of the center of gravity for the overall mass distribution.

[0048] Superhydrophobic and freeze-thaw resistant (ensuring freeze-thaw durability in extreme environments): Surface modification by incorporating hydrophobic agents imbues the internal pore walls with hydrophobic properties (surface contact angle greater than 120°), constructing a water-repellent barrier. Volumetric water absorption is less than 10%. During winter freezing, the extremely limited amount of free water within the pores fundamentally eliminates the source of frost heave stress, effectively preventing damage to the material's microstructure and endowing the device with exceptional freeze-thaw durability.

[0049] Ultimate compaction energy absorption (ultimate impact redundancy protection): When subjected to extreme impacts exceeding design conditions (such as impacts from large ships or impacts from giant floating objects during floods), the numerous micropores and macropores (porosity 50%~80%) within the material undergo irreversible collapse, compaction, and fragmentation under intense compression. This compaction process consumes enormous mechanical work, efficiently dissipating the remaining kinetic energy in the form of plastic deformation and fracture energy, serving as a safety redundancy to provide ultimate protection for the bridge piers.

[0050] Damage Stability Maintenance: When the outer casing of the device is accidentally damaged and water enters, the hydrophobic properties of the material effectively repel water intrusion through its internal pores, preventing water from filling the casing. This not only avoids a dramatic increase in draft due to the material absorbing water and increasing its weight, but also ensures the relative stability of the device's total mass and the volume of water discharged, preventing the device from tilting and sinking due to loss of buoyancy or shift in the center of gravity. This "damage-resistant, damage-resistant stability" design greatly enhances the device's survivability after sudden accidents.

[0051] To protect the internal force transmission mechanism from corrosion by the mixture of ice and water in cold regions, this embodiment also incorporates a dynamic sealing structure. Specifically, a flexible waterproof cloth is installed at the gap between the ice-breaking guide section 1 and the middle section 2, which is reserved for longitudinal displacement. This flexible waterproof cloth forms a dynamic seal at the longitudinal displacement gap between the ice-breaking guide section 1 and the middle section 2.

[0052] Specifically, one end of the high-strength waterproof fabric 9 is fixed to the rear end face of the ice-breaking guide segment 1, and the other end is fixed to the front end face of the middle segment 2, transforming the open physical gap into a closed, flexible protective cavity. The waterproof fabric 9 is made of flexible, wear-resistant polyethylene material, possessing excellent ductility and fatigue resistance. When the ice-breaking guide segment 1 is impacted and retracts, the waterproof fabric 9 folds synchronously (like accordion pleats); when the segment resets, the waterproof fabric 9 unfolds synchronously. This dynamic seal always follows the movement of the mechanism, effectively preventing ice, silt, and water from intruding into the gap, without increasing any mechanical resistance or affecting the timing reset accuracy.

[0053] With its extremely low cost and minimalist structure, this design solves the long-standing problems of ice jamming and frost heave damage that have plagued mobile mechanisms in cold regions, ensuring the long-term reliability of the core transmission connecting rod 41 and the self-resetting element 42 in harsh environments.

[0054] Please see Figure 9 In addition, the present invention also provides a method for preparing a self-floating bridge pier anti-icing collision device, comprising the following steps: S110 (Shell Preparation): Based on the design drawings, high-energy-absorbing alloy steel is used to prepare the ice-breaking guide segment 1, the middle segment 2, and the tail segment 3, each with a predetermined geometric shape, through processes such as cutting, rolling, and welding. A composite material anti-corrosion coating and warning paint are applied to the surface of the shells.

[0055] S120 (Preparation of Filler Material): Based on buoyancy and strength requirements, prepare materials with an apparent density of 200–1000 kg / m³. 3 A continuously adjustable superhydrophobic porous cement-based composite material within a certain range is used as an energy-absorbing filler material.

[0056] S130 (Floating and Stability Parametric Design): Based on the protection water level range of the target bridge and historical hydrological data, determine the design draft h of the device. d And stability requirements (such as the initial stability height GM value). Through parametric iterative calculations, the density distribution scheme of the energy-absorbing filling material 8 in different regions (such as upper and lower layers, left and right sides) inside the device is determined.

[0057] Specifically, using Archimedes' principle of buoyancy, buoyancy and gravity are balanced: Right now: In the formula: ρ 水 The density of the local water body (1000 kg / m³ for freshwater) 3 ); V 排 For the device at a draft depth h d The drainage volume; m 壳 The total mass (kg) of the steel structure shell, all functional components and accessories of the device. m 内 Total mass (kg) of energy-absorbing material filling the inside of the device; The mass of the internal energy-absorbing material is determined by the following formula: ρ 填 The apparent density of superhydrophobic porous cement-based composite materials can range from 200 to 1000 kg / m³, depending on the material mix design. 3 Continuous regulation within a specified range; V 填 The effective volume (m³) available for filling inside the device. 3 ).

[0058] At a draft of h d The drainage volume V below 排 Calculate using the following formula: In the formula: A ω This is the cross-sectional area of ​​the device at the waterline; During the design phase, based on the protected water level range and the bridge foundation elevation, the draft h of the device is first determined. d The optimal ice-resistant draft h can be derived by pre-calculating ice discharge elevations from historical hydrological data. d Therefore, the specific density ρ of the porous cement-based composite material was determined. 填 ,Right now: In actual production, by adjusting the foaming agent dosage ratio of porous cement-based composite materials, a filler with the target apparent density can be precisely prepared, thereby locking the actual draft of the device near the preset design value and ensuring that the ice-breaking guide section 1 is always in the effective ice-facing height range under different river water levels.

[0059] S140 (gradient filling): According to the density distribution scheme determined in S130, energy-absorbing filling materials 8 with different apparent densities are filled into the corresponding cavities of the middle segment 2 and the tail segment 3, and then cured and formed.

[0060] S150 (Modular Assembly): The ice-breaking guide segment 1 and the middle segment 2 are movably connected by the force transmission connecting rod 41 and the pre-compression spring array, and the pre-compression pressure is applied to set its critical trigger threshold F0. The middle segment 2 and the tail segment 3 are fastened together by the connecting flange and high-strength bolts.

[0061] S160 (Buffer Layer Covering): On the outside of the outer shell, a compression-resistant buffer layer 7 made of polymer rubber with a closed cavity is covered and fixed.

[0062] This preparation method combines advanced materials science (porous cement-based composite materials) with traditional mechanical manufacturing. Through parametric design, it achieves quantitative customization of device performance, ensuring that the final product can accurately match the anti-icing requirements of the target bridge.

[0063] In S120, the specific method for preparing superhydrophobic porous cement-based composite materials is as follows: using ordinary silicate cement as the matrix, appropriate amounts of fly ash and silica fume are added, and a foaming agent (such as hydrogen peroxide) is added. The apparent density of the material is precisely adjusted by controlling its dosage (e.g., 0.5%~5%). Simultaneously, calcium stearate or silane powder with a mass fraction of 1%~3% is added as a hydrophobic agent. After uniform stirring, pouring, and curing, superhydrophobic properties with an internal pore wall surface contact angle greater than 120° can be obtained.

[0064] This method is mature and cost-controllable, and can stably prepare filling materials that combine low density, high hydrophobicity and sufficient strength, providing a material basis for precise control of the floating state and freeze-thaw resistance of the device.

[0065] To address the potential initial mass imbalance of the device (especially due to the eccentric arrangement or internal structural asymmetry of the ice-breaking guide segment 1), in step three, when determining the density distribution scheme, a center of gravity active control method combining the mass moment balance compensation method and the parameterized linkage iterative algorithm is specifically adopted. This method utilizes the adjustable density characteristics of the energy-absorbing filling material 8 and the partitioned filling process. By filling the filling chambers on the ice-facing and ice-repelling sides with energy-absorbing filling material 8 of different densities, a reverse mass moment is constructed to offset the initial eccentric moment, ensuring that the device's center of gravity projection is located near the centroid of the waterline. This achieves three-dimensional precise control of the device's center of gravity position, ensuring that the device maintains an effective protective height and a stable floating attitude under conditions of significant water level changes. Specifically: Vertical center of gravity adjustment: The self-buoyancy stability of this device requires sufficient restoring moment after being disturbed by waves, currents, or ice impacts to prevent capsizing or excessive tilting. According to the theory of buoyancy stability, its initial stability height GM should satisfy: In the formula: Let I be the distance from the center of buoyancy to the center of stability. WL The moment of inertia of the waterline surface area about the longitudinal central axis KB is the height of the center of buoyancy, which is the centroid of the displaced volume, approximately... ; KG represents the height of the system's center of gravity from the baseline. For this device, the position of the center of buoyancy (KB) and the value of BM are determined by the outer shell geometry and the shape of the waterline, and are essentially fixed during the structural design phase. Therefore, actively adjusting the center of gravity height (KG) is a key means to optimize floating stability.

[0066] This embodiment utilizes the adjustable density of the energy-absorbing filler material 8 and a zoned filling process to achieve precise control of the center of gravity height. The specific method is as follows: 1) Vertical Center of Gravity Adjustment (see schematic diagram 8): The device is divided into lower, middle, and upper sections. By filling different heights with composite materials of varying densities, the overall center of gravity (kg) can be significantly lowered without changing the total drainage volume and weight. For example: The lower part uses a high-density material with an apparent density ranging from 500 to 1000 kg / m³. 3 To lower the center of gravity; The upper part uses a low-density material with an apparent density ranging from 200 to 400 kg / m³. 3 To reduce the mass of the upper part.

[0067] With the center of gravity lowered, the GM value increases (due to the decrease in KG), and the roll stiffness and anti-overturning ability of the device are improved simultaneously.

[0068] 2) Horizontal center of gravity adjustment (see schematic diagram 8): based on the mass moment balance compensation method To address the issue of uneven mass distribution on the left and right sides of the device caused by the eccentric arrangement of the ice-breaking guide segment 1 or the asymmetry of its internal structure, this embodiment employs a mass moment balance compensation method for regulation.

[0069] The specific implementation method is as follows: First, the initial mass eccentricity of the computing device about the vertical axis: in: G is the total weight of the device (N); e represents the distance (m) of each infinitesimal mass from the central longitudinal section, i.e., the eccentricity.

[0070] If the center of gravity is biased towards the ice-facing side, then a higher density material (e.g., 800–1000 kg / m³) should be used in the filling chamber on the ice-repelling side. 3 Alternatively, use lower density materials (such as 200–400 kg / m³) on the ice-facing side. 3 ).

[0071] By using this differential density filling process, reverse mass moments are constructed on the left and right sides to counteract the initial eccentric moment, so that the final center of gravity projection is strictly located near the centroid of the waterline, thereby avoiding the device from tilting initially in still water and ensuring that the ice-breaking guide segment 1 is always in the designed orientation.

[0072] 3) Optimization of the linkage between the center of buoyancy and the center of gravity: Parametric iterative design process: After initially determining the outer shell geometry and design draft, parametric iterative calculations are required to determine the optimal stability scheme. The specific steps are as follows: Step a: Preliminary calculation of geometric parameters: Calculate the drainage volume V based on the shell profile diagram. 排 The centroid, i.e., the height of the center of buoyancy KB0, is given by the moment of inertia I at the waterline. WL Thus, the geocentric radius BM0 is obtained.

[0073] Step b: Center of gravity prediction: Based on the mass distribution of the steel structure and the initially set homogeneous filling density, estimate the initial center of gravity height KG0.

[0074] Step c: Stability check: Calculate the initial stability height GM0 = BM0 + KB0 - KG0, and determine whether it meets the safety threshold required by the specification.

[0075] Step d: Coordinated Adjustment: If GM0 is insufficient, prioritize initiating the center of gravity downward shift strategy, reducing KG by increasing the bottom filling density; if center of gravity adjustment is limited, trigger the buoyancy and center of gravity lifting strategy, appropriately widening the waterline width or adding lateral stabilizing wings to increase I. WL This will increase the BM value.

[0076] Step e: Through the iterative process of “vertical adjustment of center of gravity” and “geometric correction of waterline” mentioned above, until the GM value and roll period both meet the design specifications, the final shell size and internal density distribution scheme are formed.

[0077] The above-mentioned quantitative control method for buoyancy and stability highly depends on the apparent density of the superhydrophobic porous cement-based composite material in this invention being between 200 and 1000 kg / m³. 3 The device exhibits continuously adjustable characteristics. Existing homogeneous filling or fixed counterweight methods cannot achieve the refined iterative solution and physical manufacturing of the above parameters. This method enables the quantitative and precise design of draft and initial stability height (GM), ensuring that the device is always in the optimal working position under different river water levels.

[0078] 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 the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some or all of the technical features therein. Such modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the embodiments of the present invention, and they should all be covered within the scope of the claims and specification of the present invention.

Claims

1. A self-floating bridge pier anti-icing collision device, characterized in that, The system includes a main casing that is fitted around the connecting pier. The main casing includes an ice-breaking guide segment, a middle segment, and a tail segment arranged longitudinally. The ice-breaking guide segment and the middle segment are connected by an elastic connecting element. The elastic connecting element has a preset critical trigger threshold, which is used to compress to absorb energy when the impact force exceeds the threshold and drive the ice-breaking guide segment to reset after the impact force is removed. The main casing is filled with energy-absorbing material.

2. The self-floating bridge pier anti-icing collision device according to claim 1, characterized in that, The ice-breaking guide segment has a guide surface with a dual-angle composite geometry design. The guide surface has an included angle of 70° to 110° in the horizontal plane to induce brittle fracture of the ice. The guide surface has an inclination angle of 60° to 85° in the vertical direction to induce bending fracture of the ice.

3. The self-floating bridge pier anti-icing collision device according to claim 1, characterized in that, The elastic connection recovery component includes a connecting rod and a self-resetting element. The self-resetting element is a pre-compression spring array, which is disposed in a mounting hole within the middle segment. The connecting rod is slidably inserted into the mounting hole, with one end fixedly connected to the ice-breaking guide segment and the other end connected to the pre-compression spring array. The pre-compression spring array has a preset critical trigger threshold, which is determined based on the critical reaction force required for the ice floe in the target river section to bend and break. Furthermore, the stiffness coefficient k of the pre-compression spring array satisfies both the upper limit constraint of the reaction force and the lower limit constraint of the energy. The upper limit constraint of the reaction force: at the extreme compression stroke S max The total reaction force F below max Less than the allowable bearing capacity threshold P of the bridge pier, i.e. Where F0 is the critical trigger threshold; The energy lower limit constraint: Under the extreme impact kinetic energy of the target, the compression stroke of the spring is not exhausted.

4. The self-floating bridge pier anti-icing collision device according to claim 1, characterized in that, It also includes a U-shaped energy-consuming element and a limiting rod; the U-shaped energy-consuming element is disposed between the inner wall of the main body of the casing and the pier; one end of the limiting rod is fixed to the middle segment, and the other end can slide into the positioning hole of the ice-breaking and guiding segment to constrain its lateral and vertical offset.

5. The self-floating bridge pier anti-icing collision device according to claim 1, characterized in that, The outer shell of the main body of the casing is covered with an anti-compression buffer layer, which is a honeycomb hollow tubular buffer pad made of polymer rubber. Each hollow tubular unit has a sealing end face at both ends of the axial direction, forming an independent closed cavity.

6. The self-floating bridge pier anti-icing collision device according to claim 1, characterized in that, The energy-absorbing filler material is a superhydrophobic porous cement-based composite material. The apparent density of the superhydrophobic porous cement-based composite material is adjustable, and the internal pore walls of the superhydrophobic porous cement-based composite material have hydrophobic properties.

7. The self-floating bridge pier anti-icing collision device according to claim 1, characterized in that, The system also includes a flexible waterproof fabric, which forms a dynamic seal at the longitudinal displacement gap between the ice-breaking guide segment and the middle segment.

8. A method for preparing a self-floating bridge pier anti-icing collision device based on any one of claims 1 to 7, characterized in that, Includes the following steps: Step 1: Prepare the outer shell of the ice-breaking guide segment, the middle segment shell, and the tail segment shell with a preset geometry; Step 2: Prepare materials with an apparent density of 200–1000 kg / m³ 3 A continuously tunable superhydrophobic porous cement-based composite material within a certain range, used as an energy-absorbing filler material; Step 3: Based on the protection water level range and hydrological data of the target bridge, determine the design draft and stability requirements of the device, and determine the density distribution scheme of the energy-absorbing filling material in different areas inside the device through parametric iterative calculation. Step 4: According to the density distribution scheme, fill the corresponding chambers of the middle segment and the tail segment with energy-absorbing filling materials of different apparent densities respectively; Step 5: Connect the ice-breaking guide segment and the middle segment through the elastic connection restorer, assemble the middle segment and the tail segment through the connecting flange, and apply pre-pressure to the elastic connection restorer of the middle segment to set its critical trigger threshold. Step 6: Wrap and fix a compression-resistant buffer layer with a closed cavity made of polymer rubber to the outside of the outer shell.

9. The method for preparing the self-floating bridge pier anti-icing collision device according to claim 8, characterized in that, The method for preparing superhydrophobic porous cement-based composite materials in step two includes: controlling the apparent density by adjusting the amount of foaming agent, and adding a hydrophobic agent to make the surface contact angle of the internal pore walls greater than 120°.

10. The method for preparing the self-floating bridge pier anti-icing collision device according to claim 8, characterized in that, The method for determining the density distribution scheme in step three includes an active center of gravity control method using a mass moment balance compensation method and a parameterized linkage iterative algorithm. By filling the filling chambers on the ice-facing side and the ice-repelling side with energy-absorbing filling materials of different densities, a reverse mass moment is constructed to counteract the initial eccentric moment, so that the center of gravity projection of the device is located near the centroid of the waterline.

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