Pier top embedded parts, eccentric force transmission parts and cantilever type anti-falling beam limit devices

Abstract

A pier-top embedded part, an eccentric force transmission part and a cantilever type anti-falling beam limiting device. The pier-top embedded part includes an embedded plate, on which a force transmission cylinder is provided. A first eccentric block is arranged in the inner cavity of the force transmission cylinder, and a through hole is provided on it. The axis line of the through hole is eccentric with the axis line of the force transmission cylinder. The eccentric force transmission part includes a force transmission cup body and a loading ring. A second eccentric block for inserting into the through hole on the first eccentric block is provided on the bottom surface of the force transmission cup body, and the loading ring is inserted into the inner cavity of the force transmission cup body. The cantilever type anti-falling beam limiting device includes a beam-bottom embedded sleeve assembly, a pier-top embedded part, an eccentric force transmission part connected to the pier-top embedded part, and a limiting tenon elastically installed between the beam-bottom embedded sleeve assembly and the loading ring of the eccentric force transmission part. The beam-bottom embedded sleeve assembly is embedded in the beam bottom plate concrete, and the pier-top embedded part is embedded on the surface of the pier top concrete. The structure of the present invention is simply designed, the installation of the limiting tenon can be smoothly realized, and in use, it can play a role in seismic isolation and vibration reduction and limiting, and can also improve the anti-falling beam ability.

Description

Technical Field

[0001] The present invention relates to the technical field of bridge seismic isolation and vibration reduction, and particularly relates to a pier top embedded part, an eccentric force transmission part and a cantilever type anti-falling beam limiting device. Background Art

[0002] During an earthquake, the falling of the beam body is one of the main forms of bridge earthquake damage. The falling beam will cause great damage to the bridge structure, and the difficulty of post-earthquake repair is also extremely high. Therefore, in bridge seismic design, preventing the earthquake-induced falling of the beam is a very important issue.

[0003] In the past bridge seismic design, a limiting block device was set between the beam body and the pier or abutment. When an earthquake occurs, after the support bolts are sheared, the limiting block will limit the excessive displacement between the beam body and the pier and abutment, playing a role in preventing the beam body from falling. At the same time, the limiting block directly transmits the seismic force of the main beam to the pier or abutment.

[0004] The block type limiting device is often used as an anti-falling beam device for bridges, especially railway bridges. However, the longitudinal and transverse directions of this limiting device are separated and made of profiled steel, with a relatively large volume. The deficiencies of the block type limiting device are as follows:

[0005] (1) Its working performance is controlled by the gap between the block and the bearing padstone. When the gap is small, the temperature force of the beam body cannot be effectively released. When the gap is large, there will be a collision between the block and the bearing padstone during an earthquake, thus affecting the anti-falling beam function;

[0006] (2) During an earthquake, the block basically does not have the function of seismic isolation and vibration reduction, and the force deformation of the block cannot be accurately calculated, and the collision effect and its damage are difficult to estimate;

[0007] (3) When the beam body displaces, only the block on one side plays a role, and the block is an anisotropic component with an obvious weak axis direction.

[0008] In recent years, the tenon-shaped anti-falling beam device promoted and used in railway bridges is a new type of anti-falling beam device with the function of seismic isolation and vibration reduction. A limiting steel tenon is set between the beam body and the pier and abutment. When an earthquake occurs, the plastic deformation of the limiting steel tenon plays an effect of extending the structural period and reducing vibration and consuming energy. At the same time, the limiting steel tenon plays a role in controlling the beam body from generating excessive post-earthquake displacement and preventing the beam from falling. It is a major technological progress in bridge seismic design.

[0009] The structural form of the tenon-shaped anti-falling beam device is: force transmission steel cylinders are respectively embedded at the beam bottom and the pier top, and both ends of the limiting steel tenon are respectively inserted into the two steel cylinders to realize the force transmission and deformation of the steel tenon.

[0010] Since the steel cylinders embedded at the bottom of the beam are embedded in the beam yard when the beam body is precast, while the steel cylinders embedded at the pier top are embedded during the on-site construction of the pier and abutment. The current situation of off-site construction makes it very difficult to align the positions of the upper and lower steel cylinders, thus causing difficulties in installing the limiting steel tenons. Although the tenon-shaped anti-falling beam device is designed with an eccentric flange device, due to its small eccentric adjustment amount, it is still difficult to meet the needs of installing the limiting steel tenons. Therefore, in current actual engineering construction, the construction method of burying the steel cylinders embedded at the pier top by on-site alignment after the beam erection is mostly adopted, which not only increases the construction procedures and construction difficulties, but also increases the construction cost. Summary of the Invention

[0011] The purpose of the present invention is to provide a pier top embedded part, an eccentric force transmission part and a cantilever type anti-falling beam limiting device, whose structural design is simple, can smoothly realize the installation of the limiting tenon, can play a role in seismic isolation and vibration reduction and limiting during use, and can also improve the anti-falling beam ability.

[0012] In order to achieve the above purpose, the present invention provides a pier top embedded part, which includes an embedded plate, a force transmission cylinder is arranged on the embedded plate, a first eccentric block is arranged in the inner cavity of the force transmission cylinder, a through hole is arranged on the first eccentric block, and the axis line of the through hole is eccentrically arranged with the axis line of the force transmission cylinder.

[0013] Preferably, the through hole is a polygonal prism hole.

[0014] Preferably, a plurality of connecting bars for being embedded in the pier top concrete are arranged under the embedded plate.

[0015] An eccentric force transmission part, which includes a force transmission cup body and a loading ring. A second eccentric block for being inserted into the through hole on the first eccentric block of the pier top embedded part is arranged on the cup bottom surface of the force transmission cup body, and the loading ring is inserted into the inner cavity of the force transmission cup body.

[0016] Preferably, the second eccentric block is a polygonal prism body, and the outer side shape of the second eccentric block matches at least part of the inner side shape of the through hole.

[0017] A cantilever type anti-falling beam limiting device, which includes a beam bottom embedded sleeve assembly, the pier top embedded part, the eccentric force transmission part connected to the pier top embedded part, and a plastically deformable limiting tenon elastically installed between the beam bottom embedded sleeve assembly and the loading ring of the eccentric force transmission part. The beam bottom embedded sleeve assembly is embedded in the beam bottom plate concrete, and the pier top embedded part is embedded on the surface of the pier top concrete.

[0018] Preferably, the limiting tenon is a tenon body structure with a variable cross-section along the axial direction.

[0019] Preferably, the limiting tenon has a spindle-shaped structure with thin upper and lower parts and a thick middle part. The cross-section of the limiting tenon is circular, and the diameters of its upper and lower ends are 0.6 to 0.65 times the diameter of the middle part.

[0020] Preferably, the limiting tenon is made of carbon steel LY345Q.

[0021] Preferably, the beam bottom embedded sleeve assembly includes an upper sleeve and a lower sleeve. The upper sleeve is sleeved on the upper end of the lower sleeve. A limiting cover is installed at the upper end of the inner cavity of the lower sleeve. The upper end of the limiting tenon is inserted into the inner cavity of the limiting cover and abuts against the upper end of the inner cavity of the limiting cover. A first gap for releasing the horizontal displacement of the temperature force is formed between the inner cavity and the limiting tenon.

[0022] Preferably, a pressure-bearing ring is installed at the lower end of the inner cavity of the lower sleeve. The limiting tenon passes through the pressure-bearing ring, and the pressure-bearing ring supports the limiting tenon.

[0023] Preferably, a stiffening ring is arranged at the lower end of the outer surface of the lower sleeve. The stiffening ring is connected to the pressing plate below it by bolts, and the pressure-bearing ring is arranged on the pressing plate.

[0024] Preferably, a plurality of stiffening ribs are arranged along the circumferential direction at the lower part of the outer surface of the lower sleeve.

[0025] Preferably, a second gap for releasing the horizontal displacement of the temperature force is formed between the lower end of the limiting tenon and the loading ring.

[0026] After adopting the above scheme, the pier top embedded parts, eccentric force transmission parts and cantilever type anti-falling beam limiting device of the present invention have the following beneficial effects:

[0027] (1) The structural design of the pier top embedded parts and the eccentric force transmission parts of the present invention is simple and ingenious. Through the insertion angle cooperation between the second eccentric block on the rotatable eccentric force transmission part and the through hole on the first eccentric block of the pier top embedded part, the eccentric distance between the beam bottom embedded sleeve assembly and the pier top embedded part can be adjusted. When the offset is not greater than 80 mm, the purpose of successfully installing the limiting tenon in place can still be achieved;

[0028] (2) The cantilever anti-falling beam limit device of the present invention has a simple design structure, clear force-bearing, simple construction and installation, easy replacement, and good seismic isolation and vibration reduction effects. By setting the limit tenon as a plastically deformable structure, it can bear the braking force of the vehicle transmitted from the beam body. After the braking force is eliminated, the elastic deformation of the limit tenon can be restored to the working state before the action of the braking force; the limit tenon can work cyclically, avoiding the possible collision with the bearing padstone of the device, improving the anti-falling beam ability. When an earthquake occurs, the device enters the plastic working section. Through the plastic energy dissipation of the limit tenon, the structural period can be extended, achieving the purpose of reducing seismic force and preventing the beam from falling. By designing the cross-section of the limit tenon as a circle, it can play a role in seismic isolation, vibration reduction and limitation for earthquakes in any horizontal direction;

[0029] (3) In the present invention, a first gap is formed between the upper end of the limit tenon and the inner cavity of the limit cover, and a second gap is formed between the lower end of the limit tenon and the loading ring. In this way, there is space for the upper and lower ends of the limit tenon to release temperature force. In the normal use state, the device is in an elastic working state and can freely and effectively release temperature force;

[0030] (4) In the present invention, by designing the length and diameter of the limit tenon, the seismic action effect can be accurately calculated, so as to realize the seismic isolation design and control of the bridge pier and foundation. Brief Description of the Drawings

[0031] Figure 1 It is a schematic structural diagram of an embodiment of the cantilever anti-falling beam limit device of the present invention;

[0032] Figure 2 It is a schematic structural diagram of the beam bottom embedded sleeve assembly of the present invention;

[0033] Figure 3 It is a front view structural diagram of the pier top embedded part of the present invention;

[0034] Figure 4 It is a top view structural diagram of the pier top embedded part of the present invention;

[0035] Figure 5 It is a front view structural diagram of the eccentric force transmission member of the present invention;

[0036] Figure 6 It is a bottom view structural diagram of the eccentric force transmission member of the present invention;

[0037] Figure 7 It is a structural diagram of the limit tenon of the present invention. Detailed Description of the Invention

[0038] The present invention will be described below according to the embodiments shown in the drawings. The embodiments disclosed this time can be considered illustrative in all aspects and are not restrictive. The scope of the present invention is not limited by the description of the following embodiments, but is only indicated by the scope of the claims, and includes all modifications within the same meaning as the scope of the claims and within the scope of the claims.

[0039] The pier top embedded parts, eccentric force transmission parts and cantilever anti-falling beam limit devices involved in the present invention and their installation methods will be specifically described below in conjunction with the drawings of the specification.

[0040] As Figure 1 shown in the schematic structural diagram of the embodiment of the cantilever anti-falling beam limit device of the present invention, it includes a beam bottom embedded sleeve assembly 1, a pier top embedded part 2, an eccentric force transmission part 3 connected to the pier top embedded part 2, and a plastically deformable limit tenon 4 elastically installed between the beam bottom embedded sleeve assembly and the eccentric force transmission part 3. The beam bottom embedded sleeve assembly 1 is embedded in the concrete of the beam bottom plate, and the pier top embedded part 2 is embedded on the surface of the pier top concrete. The upper end of the limit tenon 4 is inserted into the beam bottom embedded sleeve assembly 1 to achieve fixation, and the lower end of the limit tenon 4 is connected to the pier top embedded part 2 through the eccentric force transmission part 3.

[0041] Referring to Figure 2 shown, the beam bottom embedded sleeve assembly 1 includes an upper sleeve 5 and a lower sleeve 6. The upper sleeve 5 is sleeved on the upper end of the lower sleeve 6, and the upper end of the upper sleeve 5 is flush with the top surface of the box girder bottom plate. A limit cover 7 is installed at the upper end of the inner cavity of the lower sleeve 6. The upper end of the limit tenon 4 is inserted into the inner cavity 8 of the limit cover 7, and the upper end of the limit tenon 4 abuts against the upper end of the inner cavity 8. The inner cavity 8 is a cylindrical cavity. Referring to Figure 7 shown, the limit tenon 4 is a tenon body structure with a variable cross-section along the axial direction. It is a fusiform shape with thin upper and lower parts and a thick middle part. The cross-section of the limit tenon 4 adopts a linear change law. The cross-section of the limit tenon 4 is preferably circular. The diameters of both ends of the limit tenon 4 are 0.6 - 0.65 times the diameter of the middle part, preferably 0.63 times, to obtain the best plastic deformation effect. The limit tenon 4 is made of high-quality carbon steel LY345Q for earthquake resistance with good plasticity and toughness. A first gap for releasing the horizontal displacement of temperature force is formed between the inner cavity 8 and the upper end of the limit tenon 4, that is, the diameter of the inner cavity 8 is larger than the cross-sectional diameter of the upper end part of the limit tenon 4, forming a deformation gap for the limit tenon 4, so that the upper end of the limit tenon 4 has a space for releasing the horizontal movement of temperature force in the inner cavity 8. A pressure-bearing ring 9 is installed at the lower end of the inner cavity of the lower sleeve 6. The middle part of the limit tenon 4 passes through the pressure-bearing ring 9, and the pressure-bearing ring 9 plays a role in supporting the limit tenon 4. A stiffening ring 10 is provided at the lower end of the outer surface of the lower sleeve 6. The stiffening ring 10 is fixedly connected to the pressing plate 12 located below it through bolts 11, and the pressure-bearing ring 9 is arranged on the upper surface of the pressing plate 12. A plurality of stiffening ribs 13 are arranged along the circumferential direction at the lower part of the outer surface of the lower sleeve 6.

[0042] The above-mentioned upper sleeve 5, lower sleeve 6, stiffening ring 10 and stiffening rib 13 are all made of ordinary carbon structural steel Q235 or low alloy steel Q345.

[0043] The pressure-bearing ring 9 and the limit cover 7 are made of materials with higher strength and hardness than the limit tenon 4 according to the stress they bear. In this embodiment, 45# steel or 40Cr steel with a higher strength grade is used.

[0044] Reference Figure 3 and Figure 4 As shown, the pier top embedded part 2 includes an embedded plate 14. In this embodiment, the embedded plate 14 is rectangular. A force-transfer cylinder 15 is provided on the upper surface of the embedded plate 14. In this embodiment, the force-transfer cylinder 15 is fixed to the bottom surface of the embedded plate 14 by welding. A first eccentric block 16 is installed in the inner cavity of the force-transfer cylinder 15. The first eccentric block 16 matches the shape of the inner cavity of the force-transfer cylinder 15 and is inserted into the inner cavity of the force-transfer cylinder 15. A through hole 17 is provided on the first eccentric block 16. The through hole 17 is a polygonal prism hole. In this embodiment, the through hole 17 is a 12-sided through hole. The through hole 17 is an eccentric hole, and its axis line is eccentrically arranged with the axis line of the force-transfer cylinder 15. A plurality of connecting bars 18 for embedding and fixing in the pier top concrete are provided below the embedded plate 14, which can meet the needs of transmitting horizontal force and bending moment.

[0045] The pier top embedded part 2 is embedded on the surface of the pier top concrete during the construction of the pier. The embedded plate 14 is flush with the pier top surface. The pier top embedded part 2 is anchored in the concrete through a plurality of connecting bars 18 to realize the force transmission of the anti-falling beam device.

[0046] An eccentric force-transfer member 3 is inserted into the through hole 17 of the first eccentric block 16. Reference Figure 5 and Figure 6 As shown, the eccentric force-transfer member 3 includes a force-transfer cup body 19 and a loading ring 20. A second eccentric block 21 for inserting together with the through hole 17 of the first eccentric block 16 is provided on the cup bottom surface of the force-transfer cup body 19. The second eccentric block 21 is a polygonal prism body. The shape of the outer side surface of the second eccentric block 21 corresponds to at least part of the shape of the inner side surface of the through hole 17. In this embodiment, the second eccentric block 21 is a hexagonal prism body. The second eccentric block 21 matches the 12-sided through hole 17 of the first eccentric block 16 and can realize a rotation with a step of 30°, that is, the second eccentric block 21 can be inserted into the through hole 17 at a step of 30°, and then combined with the rotation of the first eccentric block 16 to meet different eccentricity requirements.

[0047] The loading ring 20 is inserted into the inner cavity of the force - transmitting cup body 19. The lower end of the limit tenon 4 extends into the

[22] of the loading ring 20. The

[22] is a round hole. A second gap for releasing the horizontal displacement of the temperature force is formed between the lower end of the limit tenon 4 and the

[22] of the loading ring 20, that is, the diameter of the

[22] is larger than the cross - sectional diameter of the lower part of the limit tenon 4, forming a deformation gap for the limit tenon 4, so that the lower end of the limit tenon 4 has a space for releasing the horizontal movement of the temperature force within the

[22] , and the lower end of the limit tenon 4 forms a cantilever structure.

[0048] Setting the eccentric force - transmitting member 3 between the limit tenon 4 and the pier - top embedded part 2 as described above can ensure that when the position difference between the beam - bottom embedded sleeve assembly 1 and the pier - top embedded part 2 does not exceed 80 mm, the limit tenon 4 can still be successfully installed in place.

[0049] The above - mentioned embedded plate 14 and force - transmitting cup body 19 are made of ordinary carbon structural steel Q235 or low - alloy steel Q345. The loading ring 20, the first eccentric block 16 and the second eccentric block 21 are made of materials with higher strength and hardness than the limit tenon 4 according to the stress they bear. In this embodiment, they are made of No. 45 steel or 40Cr steel with a higher strength grade.

[0050] Reference Figure 1 As shown, the beam - bottom embedded sleeve assembly 1 of the present invention is embedded in the beam - end bottom - plate concrete 23 during the pre - casting of the beam body, and the pier - top embedded part 2 is embedded on the surface of the pier - top concrete 24 during the construction of the bridge pier. After the beam is in place, the limit tenon 4 is hoisted and passed through the inner cavity 8 of the limit cover 7 of the lower sleeve 6, and the insertion angle between the second eccentric block 21 of the eccentric force - transmitting member 3 and the 12 - sided through - hole 17 on the first eccentric block 16 of the pier - top embedded part 2 is adjusted so that the lower end of the limit tenon 4 is inserted into the

[22] of the loading ring 20 of the eccentric force - transmitting member 3.

[0051] After the above installation is completed, the upper sleeve 5 of the beam - bottom embedded sleeve assembly 1 is filled with foamed polyurethane and the surface is leveled with mortar.

[0052] Under the normal use state (during the bridge operation stage), the limit tenon 4 can freely release the temperature force through the first gap between it and the beam - bottom embedded sleeve assembly 1 and the second gap between it and the eccentric force - transmitting member 3; when a high - intensity earthquake occurs, the limit tenon 4 enters the plastic energy - dissipation working state, realizes the consumption of seismic energy and the extension of the structural period, and achieves the purpose of reducing the seismic force. At the same time, the limit tenon 4 has the function of restricting the displacement of the bridge and preventing the occurrence of the beam - falling accident during an earthquake. The present invention has prominent advantages such as clear concept, definite principle, simple production, convenient installation and replacement.

[0053] The structural design of the pier top embedded part 2 and the eccentric force transmission part 3 of the present invention is simple and ingenious. By the insertion angle cooperation between the second eccentric block 22 on the rotatable eccentric force transmission part 3 and the through hole 17 on the first eccentric block 16 of the pier top embedded part 2, the eccentric distance between the beam bottom embedded sleeve assembly 1 and the pier top embedded part 2 can be adjusted. When the offset is not greater than 80 mm, the purpose of successfully installing the limit tenon 4 in place can still be achieved.

[0054] The cantilever type anti-falling beam limit device of the present invention has a simple design structure, clear force transmission, convenient construction and installation, easy replacement, and good seismic isolation and vibration reduction effects. By setting the limit tenon 4 as a plastically deformable structure, it can bear the vehicle braking force transmitted by the beam body. After the braking force is eliminated, the elastic deformation of the limit tenon 4 can be restored to the working state before the action of the braking force; the limit tenon 4 can work cyclically, avoiding the situation that the device may collide with the bearing pad stone, improving the anti-falling beam ability. When an earthquake occurs, the device enters the plastic working section, and the plastic energy dissipation of the limit tenon 4 can extend the structural period, achieving the purpose of reducing seismic force and preventing the beam from falling. By designing the cross-section of the limit tenon 4 as a circle, it can play a role in seismic isolation, vibration reduction and limit for earthquakes in any horizontal direction.

[0055] In the present invention, a first gap is formed between the upper end of the limit tenon 4 and the inner cavity 8 of the limit cover 7, and a second gap is formed between the lower end of the limit tenon 4 and the 22 of the loading ring 20. In this way, there is space for the upper and lower ends of the limit tenon 4 to release the temperature force. Under normal use conditions, the device is in an elastic working state and can freely and effectively release the temperature force.

[0056] In the present invention, by designing the length and diameter of the limit tenon 4, the seismic action effect can be accurately calculated, so as to realize the seismic isolation design and control of the bridge pier and foundation.

[0057] After considering the specification and practicing the invention disclosed herein, those skilled in the art will readily conceive of other embodiments of the present invention. This application is intended to cover any variations, uses, or adaptations of the present invention, which follow the general principles of the present invention and include known common knowledge or conventional technical means in the technical field not disclosed herein. The specification and examples are only regarded as exemplary, and the true scope and spirit of the present invention are pointed out by the following claims.

[0058] It should be understood that the present invention is not limited to the exact structure described above and shown in the drawings, and various modifications and changes can be made without departing from its scope. The scope of the present invention is only limited by the appended claims.

Claims

1. A cantilever type anti-falling beam limiting device, characterized in that, It includes a sleeve assembly embedded at the bottom of the beam, a pre-embedded part at the top of the pier, an eccentric force transfer member connected to the pre-embedded part at the top of the pier, and a plastically deformable limit tenon elastically installed between the sleeve assembly embedded at the bottom of the beam and the loading ring of the eccentric force transfer member. The pre-embedded part at the top of the pier includes a pre-embedded plate, on which a force transfer cylinder is provided. A first eccentric block is arranged in the inner cavity of the force transfer cylinder. A through hole is provided on the first eccentric block, and the axis line of the through hole is eccentrically arranged with respect to the axis line of the force transfer cylinder; the through hole is a polygonal prism hole; a plurality of connecting bars for being embedded in the pier top concrete are provided on the lower surface of the pre-embedded plate; the eccentric force transfer member includes a force transfer cup body and the loading ring. A second eccentric block for being inserted into the through hole on the first eccentric block is provided on the cup bottom surface of the force transfer cup body. The loading ring is inserted into the inner cavity of the force transfer cup body; the second eccentric block is a polygonal prism body, and the shape of the outer side surface of the second eccentric block matches at least part of the shape of the inner side surface of the through hole. The sleeve assembly embedded at the bottom of the beam is embedded in the beam bottom plate concrete, and the pre-embedded part at the top of the pier is embedded on the surface of the pier top concrete.

2. The cantilever type anti-falling beam limiting device according to claim 1, characterized in that, The limit tenon is a tenon structure with a variable cross-section along the axial direction.

3. The cantilever type anti-falling beam limiting device according to claim 2, characterized in that, The limit tenon is a spindle-shaped structure that is thin at the upper and lower parts and thick in the middle. The cross-section of the limit tenon is circular, and the diameters of its upper and lower ends are 0.6 to 0.65 times the diameter of the middle part.

4. The cantilever type anti-falling beam limiting device according to any one of claims 1-3, characterized in that, The limit tenon is made of carbon steel LY345Q.

5. The cantilever type anti-falling beam limiting device according to claim 1, characterized in that, The sleeve assembly embedded at the bottom of the beam includes an upper sleeve and a lower sleeve. The upper sleeve is sleeved on the upper end of the lower sleeve. A limit cover is installed at the upper end of the inner cavity of the lower sleeve. The upper end of the limit tenon is inserted into the inner cavity of the limit cover and abuts against the upper end of the inner cavity of the limit cover. A first gap for releasing the horizontal displacement of the temperature force is formed between the inner cavity and the limit tenon.

6. The cantilever type anti-falling beam limiting device according to claim 5, characterized in that, A pressure-bearing ring is installed at the lower end of the inner cavity of the lower sleeve. The limit tenon passes through the pressure-bearing ring, and the pressure-bearing ring supports the limit tenon.

7. The cantilever type anti-falling beam limiting device according to claim 6, wherein, A stiffening ring is arranged at the lower end of the outer surface of the lower sleeve. The stiffening ring is connected to the pressing plate below it by bolts, and the pressure-bearing ring is arranged on the pressing plate.

8. The cantilever type anti-falling beam limiting device according to claim 7, characterized in that, A plurality of stiffening ribs are arranged along the circumferential direction at the lower part of the outer surface of the lower sleeve.

9. The cantilever type anti-falling beam limiting device according to claim 1, characterized in that, A second gap for releasing the horizontal displacement of the temperature force is formed between the lower end of the limit tenon and the loading ring.

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