Pier flexible anti-collision device and installation method thereof

Abstract

The application provides a bridge pier flexible anti-collision device and a mounting method thereof, wherein the device comprises: a steel wire rope fixed to a bridge pier in a tension state, the steel wire rope is configured to extend from a bottom of the bridge pier to a top of the bridge pier around the bridge pier in a vertical direction and is spaced apart from a circumferential surface of the bridge pier by a certain distance; a turning support device, the turning support device is spaced apart from the bridge pier; the turning support device comprises a connecting part for being fixed to the bridge pier and a supporting part for supporting the steel wire rope; and a pre-tightening device, the pre-tightening device is connected to the turning support device, and the pre-tightening device is used for fixing the steel wire rope and adjusting the pre-stress of the steel wire rope. According to the bridge pier flexible anti-collision device provided by the application, construction is simple, the device structure is simple, the cost is low, the device is easy to obtain and easy to repair.

Description

Technical Field

[0001] The present invention relates to the technical field of bridge pier protection, and in particular to a flexible anti-collision device for a bridge pier and an installation method thereof. Background Art

[0002] Bridge piers are crucial components of bridge structures. Damage to these piers can lead to the malfunction of the bridge structure. For mountain bridges exposed to rockfall impacts and urban cross-line bridges exposed to vehicle impacts, appropriate protective measures are generally required to ensure the safety of the bridge structure under extreme impact loads.

[0003] In the process of implementing the present invention, the inventors discovered that the prior art has at least the following problems:

[0004] Current bridge pier anti-collision solutions and methods can be divided into the following three categories according to their working mechanisms:

[0005] The first is resistance, which is to improve the structure's anti-collision ability by strengthening the original structure;

[0006] The second method is to intercept the impact object by setting up non-attached concrete crash barriers, steel pipes, steel cables, etc. to prevent the structure from directly bearing the impact.

[0007] The third type is energy dissipation, which is to absorb external collision energy and play a role in structural protection by adopting a single damper, metal material, composite material, foam material or a combination of several energy dissipation materials (components).

[0008] 1. Technical solutions for strengthening the structure to improve its anti-collision capability:

[0009] The invention patent "Impact-resistant and anti-collision bridge pier" (application number: 201510514955.3) discloses an impact-resistant and anti-collision bridge pier with a casing wrapped around the outside of the pier and an anti-collision device arranged outside the casing. The improvement of the impact resistance of the pier is mainly due to the increase in the cross-section of the pier column, and the anti-collision structure set up increases the energy consumption capacity of the structure.

[0010] The utility model patent "A bridge pier reinforcement structure for river sections in mountainous areas" (application number: 202123121088.7) discloses a technical solution that can improve the impact resistance of bridge piers. By setting steel casing outside the original bridge piers and pouring concrete between the piers and the steel casing, the impact resistance of the bridge piers is improved.

[0011] 2. Technical solutions for intercepting collision objects:

[0012] The utility model patent "A multi-stage energy-absorbing buffer interception device and its damper" (application number: 202120610562.3) discloses an anti-collision device suitable for protecting ships from collisions with bridges. The multi-stage energy-absorbing buffer device absorbs energy through its own large deformation and buffering, and stops the ship outside the bridge pier. This invention has a complex structure and large size. It requires a large space for actual installation and function, and is not very suitable for protection against car collisions or falling rocks hitting bridge piers. In addition, although this patent also uses steel cables, it only uses them as basic interception components. The energy dissipation function of the anti-collision device still depends mainly on the energy dissipation of the damper.

[0013] The invention patent "A Flexible Anti-Collision Device for a Rotating Drum Interception Station with a Damping Device" (Application No. 201810223849.3) discloses a flexible anti-collision device based on energy dissipation by a damping element and using steel cables for interception. This patent shares similar principles with the aforementioned utility model patent "A Multi-stage Energy Dissipation Buffer Interception Device and Damper Thereof." The anti-collision function primarily relies on the damper's energy dissipation mechanism and is applicable to ship-bridge collisions, but not to vehicles or falling rocks impacting bridge piers.

[0014] 3. Anti-collision technology solutions based on energy-absorbing structures or materials:

[0015] The invention patent, "A Hybrid Anti-Collision Protection System Combining Steel Trusses and Composite Materials for Bridge Piers" (Application No. 201610191661.6), combines steel trusses with composite anti-collision rings to significantly absorb impact energy, improving the weak impact resistance of pier columns. While this patent does improve the impact resistance of bridge piers to a certain extent, the complex structure makes processing, installation, and maintenance difficult.

[0016] The utility model patent "A fixed bridge pier anti-collision device based on composite materials" (application number: 202122284761.2) improves the anti-collision ability of the bridge pier by setting polyurethane foam inside the anti-collision ring and anti-collision blocks outside the anti-collision ring.

[0017] The utility model patent "A unitized bridge pier anti-collision device" (application number: 20220321920.3) realizes the energy absorption protection function during collision by setting an outer steel component, an inner steel component and a plastic energy absorption component located in the middle layer.

[0018] The above are only some of the solutions similar to this technology. It should be noted that there are many different anti-collision and anti-collision solutions on the market. Different structures and materials can achieve a certain degree of anti-collision and anti-collision for bridge piers, but the overall working principles can be classified into the three categories mentioned above. A review of existing solutions shows that the current technical solutions cannot strike a balance between protective performance, manufacturing and processing costs, structural complexity, maintainability, and replaceability. This is also a major factor restricting the continued development of current anti-collision technology solutions.

[0019] Therefore, a flexible anti-collision device for a bridge pier and an installation method thereof are needed to at least partially solve the above technical problems. Summary of the Invention

[0020] The embodiment of the present invention provides a flexible anti-collision device for a bridge pier and an installation method thereof, which has simple construction, simple device structure, low cost, easy acquisition, and easy repair.

[0021] In a first aspect, the present invention provides a flexible anti-collision device for a bridge pier, the device comprising:

[0022] a steel wire rope fixed to the pier in a tensioned state, the steel wire rope being configured to extend vertically from the bottom of the pier to the top of the pier, surround the pier, and be spaced a certain distance from the circumference of the pier;

[0023] a steering support device, the steering support device being spaced apart from the bridge pier; the steering support device comprising a connecting portion for fixing to the bridge pier and a supporting portion for supporting the steel wire rope; and

[0024] A pre-tightening device is connected to the steering support device, and is used to fix the steel wire rope and adjust the prestress of the steel wire rope.

[0025] The flexible anti-collision device for bridge piers according to the present invention has a simple structure. It disperses the local impact of the colliding object on the collided object through the nonlinear elastic deformation of the pre-tightened steel wire rope under the action of collision. At the same time, the elastic retraction of the steel wire rope will change the movement path of the colliding object, further reducing the damage to the bridge piers.

[0026] Optionally, the connecting portion is constructed as a curved panel adapted to the peripheral shape of the pier, and the curved panel is fixed to the pier via fasteners.

[0027] Optionally, the support portion is constructed as an arc-shaped groove capable of accommodating the steel wire rope, with the groove opening facing the side away from the connecting portion.

[0028] Optionally, the steering support device further includes a middle portion, which is configured as an arched bridge structure, with an open side thereof connected to the connecting portion, and a side thereof facing away from the opening connected to the supporting portion.

[0029] Optionally, the device includes at least two groups of pre-tensioning devices distributed on the steering support device at the two ends of the steel wire rope, and the pre-tensioning device includes a fixed block fixed to the support part, a threaded hole is provided in the fixed block, an adjusting screw is threaded in the threaded hole, and the adjusting screw is connected to the steel wire rope.

[0030] Optionally, the steel wire ropes are arranged spirally around the pier, and the spacing between any adjacent steel wire ropes at the same vertical position is equal. And / or the connecting portion, the supporting portion and the middle portion are welded into an integrated structure.

[0031] Optionally, the steering support device is made of plastic material, so that under a large impact energy, the wire rope steering support device will undergo plastic deformation to further absorb the collision energy. And / or a protective tube is further provided on the outside of the device.

[0032] In a second aspect, the present invention further provides a method for installing a flexible anti-collision device for a bridge pier. The method comprises the following steps:

[0033] fixing the steering support devices to the bridge piers at intervals;

[0034] Fixing the pre-tightening device on the steering support device at least at the bottom end and the top end of the pier in the vertical direction, and placing the steel wire rope on the steering support device;

[0035] By adjusting the pre-tensioning device, the steel wire rope is tightened until a predetermined pre-stress is reached.

[0036] Optionally, the adjusting the pre-tightening device to tighten the steel wire rope until a predetermined pre-stress is reached specifically includes:

[0037] Obtaining initial impact parameters including impact mass and impact velocity of the collision object;

[0038] Initially establish the impact collision finite element model to obtain the design collision force;

[0039] Determine the size of the steering support device and the number, diameter, and vertical spacing parameters of the steel cables based on the designed collision force;

[0040] According to the layout parameters and impact deformation requirements of the above-mentioned wire rope, the design collision force is taken as the maximum interception force when the wire rope reaches the design deformation in the vertical direction to obtain the initial prestress of the wire rope;

[0041] Arrange the wire ropes according to their initial prestress, and verify the wire rope protection effect through the impact collision finite element model. If the impact force is reduced by more than 50%, the requirements are met. Otherwise, continue to adjust the wire rope arrangement parameters until the requirements are met.

[0042] Optionally, the adjusting the pre-tightening device to tighten the steel wire rope until a predetermined pre-stress is reached specifically includes:

[0043] Determine the mass of the collision object as m and the speed as v, and calculate the impact force F between the collision object and the pier column by simulating the finite element model of the collision object impacting the bridge pier. c ,in

[0044]

[0045] Δt is the duration of the impact process, h is the buffer thickness;

[0046] Taking n steel wire ropes intercepting a collision object as an example, the maximum interception force F of a single steel wire rope in the direction of the collision object is calculated. c / n;

[0047] Take the maximum deformation of the wire rope along the impact direction as a, the initial length L0, and the length after deformation as L1. According to the geometric relationship of wire rope deformation, we can get

[0048] From the stress-strain relationship of the wire rope, we can get

[0049] F0=ε0EA S ,

[0050] F1=ε1EA S , ΔL1=L1-L0+ΔL0, (2)

[0051] Combining formulas (1) and (2), we can get:

[0052] Where: △L0 is the initial elongation of the wire rope, △L1 is the total elongation of the wire rope after deformation, L0 is the initial length of the wire rope, L1 is the total length after deformation, F0 is the initial internal force of the wire rope, F1 is the internal force of the wire rope after elongation, E is the elastic modulus of the wire rope, As is the cross-sectional area of ​​a single strand of wire rope,

[0053] At this time, the horizontal tension provided by a single wire rope

[0054] Just That is, tension It can meet the requirement of reducing the impact force by 50%;

[0055] F0 can be obtained by substituting the F1 value that meets the requirements into formula (3). The initial prestress σ0 required for the wire rope can be calculated.

[0056] The method according to the present invention is simple to operate, and the diameter, arrangement density, pre-tensioning degree, etc. of the steel wire rope can be reasonably selected based on protection needs and supported by theoretical analysis, thus having good flexibility.

[0057] Additional advantages, objects, and features of the present invention will be set forth in part in the following description and will become apparent to those skilled in the art upon examination of the following or may be learned from practice of the present invention. The objects and other advantages of the present invention may be realized and obtained by the structures particularly pointed out in the description and drawings.

[0058] Those skilled in the art will understand that the purposes and advantages that can be achieved by the present invention are not limited to the above specific descriptions, and the above and other purposes that can be achieved by the present invention will be more clearly understood based on the following detailed description. BRIEF DESCRIPTION OF THE DRAWINGS

[0059] The drawings described herein are intended to provide a further understanding of the present invention, constitute a part of this application, and do not constitute a limitation of the present invention. The components in the drawings are not drawn to scale, but are merely for the purpose of illustrating the principles of the present invention. To facilitate the illustration and description of certain portions of the present invention, corresponding portions in the drawings may be exaggerated, that is, may be larger than other components in an exemplary device actually manufactured according to the present invention. In the drawings:

[0060] Figure 1 A schematic diagram of a flexible anti-collision device for a bridge pier according to an embodiment of the present invention;

[0061] Figure 2 This is a schematic diagram of a flexible anti-collision device for a bridge pier according to an embodiment of the present invention, with the protective tube omitted.

[0062] Figure 3 A schematic diagram of a steering support device in a flexible anti-collision device for a bridge pier according to an embodiment of the present invention;

[0063] Figure 4 This is a schematic diagram of the connection between the steering support device and the pre-tightening device in the flexible anti-collision device for a bridge pier according to one embodiment of the present invention;

[0064] Figure 5 This is a force analysis diagram of a steel wire rope in a flexible anti-collision device for a bridge pier according to an embodiment of the present invention when the steel wire rope reaches maximum deformation;

[0065] Figure 6 A flow chart of a method for installing a flexible anti-collision device for a bridge pier according to an embodiment of the present invention; and

[0066] Figure 7 This is a partial flow chart of a method for installing a flexible anti-collision device for a bridge pier according to an embodiment of the present invention.

[0067] Description of reference numerals:

[0068] 10. Bridge piers;

[0069] 100. Device;

[0070] 110. Wire rope;

[0071] 120. Steering support device; 121. Connecting portion; 122. Support portion; 123. Intermediate portion; 124. Fastener;

[0072] 130. Pre-tightening device; 131. Fixing block; 132. Adjusting screw;

[0073] 140. Protective tube. DETAILED DESCRIPTION

[0074] The objects and functions of the present invention, as well as methods for achieving these objects and functions, will be clarified with reference to exemplary embodiments. However, the present invention is not limited to the exemplary embodiments disclosed below; it can be implemented in various forms. The essence of the description is merely to help those skilled in the relevant art to comprehensively understand the specific details of the present invention.

[0075] It should be noted that the terms used herein are only for the purpose of describing specific embodiments and are not intended to limit exemplary embodiments according to the present invention. As used herein, unless the context clearly indicates otherwise, the singular form is also intended to include the plural form. In addition, it should also be understood that when the terms "comprise" and / or "include" are used in this specification, they indicate the presence of features, wholes, steps, operations, elements and / or components, but do not exclude the presence or addition of one or more other features, wholes, steps, operations, elements, components and / or combinations thereof.

[0076] Ordinal numbers such as "first" and "second" cited in the present invention are merely identifiers and do not have any other meanings, such as a specific order, etc. Moreover, for example, the term "first component" itself does not imply the existence of a "second component", and the term "second component" itself does not imply the existence of a "first component".

[0077] It should be noted that the terms "upper", "lower", "front", "back", "left", "right", "inside", "outside" and similar expressions used in this document are for illustrative purposes only and are not limiting.

[0078] The present invention provides a flexible anti-collision device 100 for a bridge pier and its installation method. The device 100 can be applied, for example, to the field of bridge pier 10 protection technology, effectively protecting the bridge pier 10 and reducing damage to the bridge pier 10 caused by falling rocks, vehicle collisions, and the like.

[0079] In a first aspect, the present invention provides a flexible anti-collision device 100 for a bridge pier. In a preferred embodiment, referring to Figures 1 to 4 As shown, Figure 1 Schematic diagram of a flexible anti-collision device 100 for a bridge pier according to an embodiment of the present invention. Figure 2 Schematic diagram of a flexible anti-collision device 100 for a bridge pier according to an embodiment of the present invention, wherein the protective tube 140 is omitted from the device 100 . Figure 3 Schematic diagram of the steering support device 120 in the flexible anti-collision device 100 of the bridge pier according to an embodiment of the present invention. Figure 4 This is a connection diagram of the steering support device 120 and the pre-tensioning device 130 in the flexible anti-collision device 100 of a bridge pier according to an embodiment of the present invention. The device 100 includes a steel wire rope 110, a steering support device 120 and a pre-tensioning device 130. The steel wire rope 110 is an important component of the device 100 and is used to directly bear the impact of the collision object. Among them, the steel wire rope 110, as the specific device 100 of the present invention, can also be replaced by a cable made of steel strands or carbon fiber reinforced composite materials. The steering support device 120 is used to install the steel wire rope 110. The pre-tensioning device 130 is used to fix the steel wire rope 110 and adjust the prestress of the steel wire rope 110.

[0080] Specifically, if Figure 2 As shown, a steel wire rope 110 is secured to the pier 10 and is in a tensioned state to meet certain prestressing requirements. The steel wire rope 110 is constructed to extend vertically from the bottom to the top of the pier 10, encircling the pier 10 and spaced a certain distance from the circumference of the pier 10 to allow space for deformation when an object strikes the steel wire rope 110.

[0081] In the illustrated embodiment, two steel cables 110 are shown spirally rising side by side around the bridge pier 10. It will be appreciated that, in embodiments not shown, a single steel cable 110 may be arranged around the bridge pier 10, or three or more steel cables 110 may be arranged around the bridge pier 10. To facilitate the arrangement of the steel cables 110 and enhance the protective effect, the steel cables 110 are arranged spirally around the bridge pier 10, with the spacing between any adjacent steel cables 110 at the same vertical position being equal, i.e., the steel cables 110 are evenly spaced, for example, at intervals of 2 cm, 3 cm, or 5 cm.

[0082] The steering support devices 120 are arranged at intervals on the pier 10. For example, the steering support devices 120 are arranged at intervals along the spiral ascending route of the steel wire rope 110. There is no limit on the number of steering support devices 120, and there are at least two of them. To improve the support effect on the steel wire rope 110, multiple steering support devices 120 can be reasonably arranged according to the actual size of the pier 10 to provide better support for the steel wire rope 110. In addition, there is no limit on the specific method of fixing the steering support device 120 to the pier 10. For example, the steering support device 120 can be fixed to the pier 10 by welding, bonding, or using fasteners 124, such as expansion bolts. The steering support device 120 can include a connecting portion 121 for fixing to the pier 10 and a supporting portion 122 for supporting the steel wire rope 110.

[0083] Among them, reference Figure 3 and Figure 4 The connecting portion 121 may be a plate-like structure, which may be fixed to the surface of the pier 10 by fasteners 124 (e.g., expansion bolts). Since the surface of the pier 10 (i.e., the circumference of the pier 10) is arc-shaped, in order to better fit and fix the connecting portion 121 to the pier 10, it is preferred that the connecting portion 121 adopts an arc-shaped plate that matches the shape of the circumference of the pier 10. The arc-shaped plate is fixed to the pier 10 by fasteners 124. In addition, in order to better support and accommodate the steel wire rope 110, and to facilitate the placement and replacement of the steel wire rope 110, the supporting portion 122 adopts an arc-shaped groove structure that can accommodate the steel wire rope 110, with the groove facing the side away from the connecting portion 121.

[0084] The pre-tensioning device 130 is connected to the steering support device 120. The pre-tensioning device 130 is used to fix the wire rope 110 and adjust the prestress of the wire rope 110. The tension of the wire rope 110 can be adjusted by the pre-tensioning device 130 until the required prestressed state is reached. In order to provide a reliable, practical and convenient pre-tensioning device 130, the pre-tensioning device 130 may include a fixing block 131. The fixing block 131 is fixed to the support portion 122. A threaded hole is provided in the fixing block 131. There is no restriction on the way the fixing block 131 is fixed to the support portion 122, and it can be welded or fixed by means of a fastener 124. The adjusting screw 132 is threaded into the threaded hole. The adjusting screw 132 is connected to the wire rope 110. The fixing block 131 can be a nut, which is easy to obtain and low in cost. Since the wire rope 110 has a certain tension after being tensioned, a tightening nut may be added to the adjusting screw 132 to improve the tightness between the fixing block 131 and the adjusting screw 132. This allows the adjusting screw 132 to be fixed after the wire rope 110 is adjusted to an appropriate prestress. There is no limit on the number of pretensioning devices 130, but at least two sets of pretensioning devices 130 are included, distributed on the steering support devices 120 at both ends of the wire rope 110. The prestress of the entire wire rope 110 can be adjusted by adjusting the pretensioning devices 130 on the steering support devices 120 at both ends of the wire rope 110. To improve the tensioning effect on the wire rope 110, multiple pretensioning devices 130 may be arranged in a reasonable manner according to the actual size of the pier 10 (or the length of the wire rope 110), and the pretensioning devices 130 may be arranged on the steering support devices 120 at appropriate locations.

[0085] According to the flexible anti-collision device 100 of the bridge pier 10 of the present invention, the structure is simple. The local impact of the colliding object on the collided object is dispersed through the nonlinear elastic deformation of the pre-tightened steel wire rope 110 under the action of collision. At the same time, the elastic retraction of the steel wire rope 110 will change the movement path of the colliding object, further reducing the damage to the bridge pier 10.

[0086] refer to Figure 3 and Figure 4In order to arrange the support portion 122 reasonably and provide a buffer distance for the steel wire rope 110 as much as possible while keeping the structure as simple as possible, the steering support device 120 also includes an intermediate portion 123. The intermediate portion 123 can be constructed as an arch bridge structure, with one side of its opening connected to the connecting portion 121, and the side away from the opening connected to the support portion 122. The intermediate portion 123 and the connecting portion 121, and the intermediate portion 123 and the support portion 122 can be connected and fixed by welding, or other connection methods can be used, which are not limited here. Preferably, the connecting portion 121, the support portion 122 and the intermediate portion 123 can be made into an integral structure by welding. In addition, the connecting portion 121, the support portion 122 and the intermediate portion 123, or at least the intermediate portion 123, are made of plastic material, so that under a large impact energy, the steel wire rope 110 steering support device 120 will undergo plastic deformation to further absorb the collision energy. For example, the connecting portion 121 , the supporting portion 122 and the middle portion 123 , or at least the middle portion 123 , are made of steel plates, which are easy to obtain, low in cost, and have a certain plastic deformation capability.

[0087] Further, refer to Figure 1 In order to further improve the protection capability of the device 100, a protective tube 140 may be provided on the outside of the device 100. For example, the protective tube 140 may be a metal tube (eg, made of steel plate, aluminum plate, etc.).

[0088] Second, reference Figure 6 The present invention also provides a method 200 for installing a flexible anti-collision device for a bridge pier. The flexible anti-collision device for a bridge pier based on the above technical solution comprises the following steps:

[0089] S210. Fix the steering support device to the bridge pier at intervals.

[0090] S220. Fix the pre-tightening device on the steering support device at least at the bottom and top ends of the pier in the vertical direction, and place the steel wire rope on the steering support device.

[0091] S230. Tighten the wire rope by adjusting the pre-tensioning device until the predetermined pre-stress is reached.

[0092] Wherein, in step S210, the steering support device is fixed to the bridge pier at intervals. Specifically, the steering support device can be fixed to the bridge pier at intervals by fasteners (such as expansion bolts).

[0093] The method according to the present invention is simple to operate, and the diameter, arrangement density, pre-tensioning degree, etc. of the steel wire rope can be reasonably selected based on protection needs and supported by theoretical analysis, thus having good flexibility.

[0094] Continue from above, reference Figure 7In step S230, the steel wire rope is tightened by adjusting the pre-tensioning device until a predetermined pre-stress is reached. Specifically, the following contents are included:

[0095] Obtain the initial impact parameters including the impact mass and impact velocity of the collision object.

[0096] A preliminary impact collision finite element model is established to obtain the design collision force. The impact collision finite element model is an existing model, and when obtaining the design collision force, it can also be studied and calculated in conjunction with relevant industry standards.

[0097] The size of the steering support device and the number, diameter and vertical spacing parameters of the steel cables are determined according to the design collision force.

[0098] Based on the aforementioned wire rope layout parameters and impact deformation requirements, the design impact force is taken as the maximum interception force when the wire rope reaches the design deformation in the vertical direction to obtain the initial prestress of the wire rope. The vertical direction is the direction of travel of the impact object when the wire rope is hit by the impact object.

[0099] Arrange the wire ropes according to their initial prestress, and verify the wire rope protection effect through the impact collision finite element model. If the impact force is reduced by more than 50%, the requirements are met. Otherwise, continue to adjust the wire rope arrangement parameters until the requirements are met.

[0100] refer to Figure 5 and Figure 7 Specifically, the steel wire rope is tightened by adjusting the pre-tensioning device until a predetermined pre-stress is reached, which specifically includes:

[0101] First, determine the mass of the collision object as m and the speed as v. Then, calculate the impact force F between the collision object and the pier column by simulating the finite element model of the collision object impacting the bridge pier. c ;in

[0102]

[0103] Δt is the duration of the impact process; h is the buffer thickness.

[0104] Secondly, taking n steel wire ropes intercepting a collision object as an example, the maximum interception force F of a single steel wire rope in the direction of the collision object is calculated. c / n.

[0105] Then, take the maximum deformation of the wire rope along the impact direction as a, the initial length L0, and the length after deformation as L1. According to the geometric relationship of wire rope deformation, we can get

[0106] Then, the stress-strain relationship of the wire rope can be obtained

[0107] F0=ε0EA S ;

[0108] F1=ε1EA S ; ΔL1=L1-L0+ΔL0; (2)

[0109] Combining formulas (1) and (2), we can get:

[0110] Where: △L0 is the initial elongation of the wire rope, △L1 is the total elongation of the wire rope after deformation, L0 represents the initial length of the wire rope, L1 is the total length after deformation, F0 is the initial internal force of the wire rope, F1 is the internal force of the wire rope after elongation, E is the elastic modulus of the wire rope, and As is the cross-sectional area of ​​a single strand of wire rope;

[0111] At this time, the horizontal tension provided by a single wire rope

[0112] Just That is, tension This can meet the requirement of reducing the impact force by 50%.

[0113] Finally, the F1 value that meets the requirements can be substituted into formula (3) to obtain F0, which is The initial prestress σ0 required for the wire rope can be calculated. During the actual installation process, the prestress of the wire rope can be measured in real time using existing measuring devices to determine whether the prestress of the wire rope reaches σ0.

[0114] Other embodiments of the present invention will be readily apparent to those skilled in the art from the description and practice of the invention disclosed herein. The description and embodiments are intended to be exemplary only, and the true scope and spirit of the present invention are defined by the claims.

Claims

1. A flexible anti-collision device for a bridge pier, characterized in that: The device comprises: a steel wire rope fixed to the bridge pier and in a tensioned state, the steel wire rope being configured to extend vertically from the bottom of the bridge pier to the top of the bridge pier in a spiral manner and surround the bridge pier, the steel wire rope being spaced a certain distance from the circumference of the bridge pier; A steering support device, the steering support device is spaced apart from the bridge pier; the steering support device comprises a connecting portion for fixing to the bridge pier, a supporting portion for supporting the steel wire rope, and an intermediate portion; wherein the connecting portion is constructed as a curved plate adapted to the circumferential shape of the bridge pier, and the curved plate is fixed to the bridge pier by fasteners; the supporting portion is constructed as an arcuate groove capable of accommodating the steel wire rope, with the groove opening facing away from the connecting portion; the intermediate portion is constructed as an arched bridge structure, with one open side of the intermediate portion connected to the connecting portion and the side away from the opening connected to the supporting portion, and the connecting portion, the supporting portion, and the intermediate portion are welded to form an integral structure; and A pre-tightening device is connected to the steering support device, and is used to fix the steel wire rope and adjust the prestress of the steel wire rope.

2. The flexible anti-collision device for bridge piers according to claim 1 is characterized in that: The pre-tightening device comprises at least two groups of pre-tightening devices distributed on the steering support device at the two ends of the steel wire rope, and the pre-tightening device comprises a fixed block fixed to the support part, a threaded hole is provided in the fixed block, an adjusting screw is threaded in the threaded hole, and the adjusting screw is connected to the steel wire rope.

3. The flexible anti-collision device for bridge piers according to claim 2, characterized in that: The steel wire ropes are arranged in a spiral manner around the bridge pier, and the spacing between any adjacent steel wire ropes at the same vertical position is equal.

4. The flexible anti-collision device for bridge piers according to claim 3 is characterized in that: The steering support device is made of plastic material; and / or A protective tube is also provided on the outside of the device.

5. A method for installing a flexible anti-collision device for a bridge pier, based on the flexible anti-collision device for a bridge pier according to any one of claims 1 to 4, characterized in that: The method comprises the following steps: fixing the steering support devices to the bridge piers at intervals; Fixing the pre-tightening device on the steering support device at least at the bottom end and the top end of the pier in the vertical direction, and placing the steel wire rope on the steering support device; By adjusting the pre-tensioning device, the steel wire rope is tightened until a predetermined pre-stress is reached.

6. The method for installing a flexible anti-collision device for a bridge pier according to claim 5, characterized in that: The method of tightening the steel wire rope until a predetermined prestress is reached by adjusting the prestressing device specifically includes: Obtaining initial impact parameters including impact mass and impact velocity of the collision object; Initially establish the impact collision finite element model to obtain the design collision force; Determine the size of the steering support device and the number, diameter, and vertical spacing parameters of the steel cables based on the designed collision force; According to the layout parameters and impact deformation requirements of the above-mentioned wire rope, the design collision force is taken as the maximum interception force when the wire rope reaches the design deformation in the vertical direction to obtain the initial prestress of the wire rope; Arrange the wire ropes according to their initial prestress, and verify the protective effect of the wire ropes through the impact collision finite element model. If the impact force is reduced by more than 50%, the requirements are met. Otherwise, continue to adjust the wire rope arrangement parameters until the requirements are met.

7. The method for installing a flexible anti-collision device for a bridge pier according to claim 6, characterized in that: The method of tightening the steel wire rope until a predetermined prestress is reached by adjusting the prestressing device specifically includes: Determine the mass of the collision object as , the speed is The impact force between the collision object and the pier column is determined by simulating the finite element model of the collision object and calculating the impact force between the collision object and the pier column. ,in is the duration of the impact process, is the buffer thickness; by Take the example of a steel wire rope intercepting a collision object to calculate the maximum interception force of a single steel wire rope on the impact direction of the collision object. ; The maximum deformation of the wire rope along the impact direction is , initial length , the length after deformation is , through the geometric relationship of wire rope deformation, we can get ; From the stress-strain relationship of the wire rope, we can get （1） （2） Combining formulas (1) and (2), we can get: , (3) Where: is the initial wire rope elongation, is the total elongation of the wire rope after deformation, Indicates the initial wire rope length, is the total length after deformation, is the initial internal force of the wire rope, is the internal force of the wire rope after extension, is the elastic modulus of the wire rope, is the cross-sectional area of ​​a single strand wire rope, At this time, the horizontal tension provided by a single wire rope , Just , that is, tension It can meet the requirement of reducing the impact force by 50%; Can be met by Substitute the value into formula (3) to obtain ,Depend on , the initial prestress required for the wire rope can be calculated .

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