Buffering device for tensioning fracture of prestressed steel strand of precast beam body

Abstract

The utility model discloses a buffering device for tensioning fracture of a prestressed steel strand of a precast beam body, and relates to the technical field of protection devices. The device structurally comprises a rectangular box body with a side opening, a main shaft, a buffer spiral pipe and a hoop mounted on the main shaft, the main shaft is vertically mounted between the upper surface and the lower surface in the rectangular box body through two mounted bearings; the buffer spiral pipe is connected with the hoop into a whole through a plurality of connecting pieces; the buffering spiral pipe comprises a spiral pipe section and a horn mouth section fixed to a lower end opening of the spiral pipe section. Kinetic energy of the broken steel strand is converted into gravitational potential energy and kinetic energy obtained by circular motion of the buffering spiral pipe and the main shaft through rotation of the buffering spiral pipe and the main shaft, impact force generated after the steel strand is broken is effectively relieved, and safety of field operation is improved. Compared with traditional rigid protection, a flexible buffering mode is adopted, impact energy is effectively absorbed and dispersed, and potential damage to personnel and equipment is reduced.

Description

Technical Field

[0001] The utility model belongs to the technical field of protective devices, in particular to a buffer device for tensioning and breaking of prestressed steel strands of prefabricated beams. Background Art

[0002] Prefabricated beam: The bridge structure generally consists of five major components: foundation, substructure, support system, superstructure, and bridge deck. With the improvement of production technology, during the bridge construction phase, the superstructure with simple structure and high repetition rate can be prefabricated in the prefabrication yard while the foundation and substructure are under construction. After the foundation and substructure are completed, it can be transported to the bridge site for hoisting, which greatly shortens the construction period. Each superstructure unit to be hoisted is called a prefabricated beam.

[0003] Prestressing is the compressive stress that is applied to the structure in advance during construction in order to improve the service performance of the structure. The prestressed compressive stress during the service life of the structure can fully or partially offset the tensile stress caused by the load and avoid structural damage. It is often used in concrete structures. Prestressed concrete structures are structures that are pre-pressed before the structure is subjected to loads, so that the internal force of the concrete in the tensile zone under the action of external loads produces compressive stress to offset or reduce the tensile stress caused by the external load, so that the structure will not crack or crack later under normal use.

[0004] Steel strand is a steel product composed of multiple steel wires twisted together. The tensile strength of the commonly used steel strand products has reached 1860MPa. Due to its extremely high tensile strength, it is often used to transmit prestress.

[0005] Prestressing: First bury the curved pipeline in the prefabricated beam. After the beam is prefabricated, insert a steel strand slightly longer than the pipeline so that both ends of the steel strand are exposed outside the pipeline. Use an anchoring device to anchor both ends of the steel strand to the jack and stretch the steel strand. The steel strand tends to return to a straight line after being stretched. The straight steel strand transfers the force transmitted by the jack to the curved pipeline, ultimately giving the beam prestress.

[0006] During the tensioning process of the steel strands, if there are slight rust or initial defects on the surface of the steel strands, or if the anchoring device is unreasonable, the steel strands may break. Because the steel strands are already in a high stress state, they will fly out from the breaking point to both ends at high speed, causing casualties and property. The prior art often uses multiple 1cm steel plates to overlap and stand behind the jack, or piles up sandbags for protection. Disadvantages: Because the steel strands fly out at high speed, it often penetrates the steel plates directly. To reduce the risk, the steel plates can only be stacked, which greatly increases the weight and makes transportation within the site very inconvenient. The situation of stacking sandbags is similar. The only way is to increase the number of sandbags, which will affect both cost and efficiency. In order to safely release the energy of the steel strands within a small range and short distance, the present application document provides a buffer device for the tensioning and fracture of prestressed steel strands of prefabricated beams. Utility Model Content

[0007] The utility model aims to provide a buffer device for the tension fracture of prestressed steel strands of prefabricated beams, which transforms the kinetic energy of the broken steel strands through a rectangular box, a main shaft, a buffer spiral tube and a clamp, thereby effectively mitigating the impact force after the steel strands are broken.

[0008] In order to solve the above technical problems, the utility model is realized by the following technical solutions:

[0009] The utility model discloses a buffer device for the tension fracture of prestressed steel strands of a prefabricated beam body, comprising a rectangular box body with a side opening, a main shaft, a buffer spiral tube and a clamp installed on the main shaft; the main shaft is vertically installed between the upper and lower surfaces inside the rectangular box body through two seat bearings; the buffer spiral tube is connected to the clamp as a whole through a plurality of connecting pieces; the buffer spiral tube comprises a spiral tube section and a bell-mouth section fixed at the lower end of the spiral tube section.

[0010] As a preferred technical solution of the utility model, at least four self-locking universal wheels are installed at the bottom of the rectangular box, which can be turned and locked at will to facilitate movement within the venue.

[0011] As a preferred technical solution of the present utility model, the connecting piece is a steel pipe, and the diameter of the steel pipe is 1-3 cm.

[0012] As a preferred technical solution of the utility model, the main shaft is a steel pipe, and the diameter of the steel pipe is 3-5 cm.

[0013] As a preferred technical solution of the present utility model, the five walls of the rectangular box are all made of 3-5 mm steel plates.

[0014] As a preferred technical solution of the utility model, the wall thickness of the spiral pipe section is 3-5 mm, and the spiral pipe section spirals upward around the main axis.

[0015] The utility model has the following beneficial effects:

[0016] 1. The utility model converts the kinetic energy of the broken steel strand into gravitational potential energy and the kinetic energy obtained by the circular motion of the buffer spiral tube and the main shaft through the rotation of the buffer spiral tube and the main shaft, which effectively reduces the impact force after the steel strand is broken and improves the safety of on-site operations.

[0017] 2. Compared with traditional rigid protection, the device of the utility model adopts a flexible buffering method, which can more effectively absorb and disperse the impact energy and reduce potential damage to personnel and equipment.

[0018] 3. The utility model can adjust the height of the buffer device by loosening the clamp to adapt it to steel strands of different lengths, thereby increasing the applicability of the device.

[0019] 4. The self-locking universal wheels installed at the bottom of the rectangular box of the utility model enable the device to be easily moved and positioned in the venue, thereby improving work efficiency.

[0020] 5. The whole device of the utility model is composed of a rectangular box, a main shaft, a buffer spiral tube and a clamp and other components, and has a simple structure and is easy to manufacture and maintain.

[0021] Of course, any product implementing the present invention does not necessarily need to achieve all of the advantages described above at the same time. BRIEF DESCRIPTION OF THE DRAWINGS

[0022] In order to more clearly illustrate the technical solutions of the embodiments of the utility model, the drawings required for describing the embodiments are briefly introduced below. Obviously, the drawings described below are only some embodiments of the utility model. For ordinary technicians in this field, other drawings can be obtained based on these drawings without creative work.

[0023] Figure 1 It is a schematic diagram of the implementation of the buffer device for the tension fracture of prestressed steel strands of a prefabricated beam according to the utility model.

[0024] In the accompanying drawings, the components represented by the reference numerals are listed as follows:

[0025] 1-rectangular box, 2-spindle, 3-buffer spiral tube, 4-hoop, 5-seat bearing, 6-connector, 7-universal wheel, 31-spiral tube section, 32-bell mouth section. DETAILED DESCRIPTION

[0026] The following will be combined with the drawings in the embodiments of the utility model to clearly and completely describe the technical solutions in the embodiments of the utility model. Obviously, the described embodiments are only part of the embodiments of the utility model, not all of the embodiments. Based on the embodiments of the utility model, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the utility model. Specific embodiment one:

[0028] See also Figure 1 As shown, the utility model is a buffer device for the tension fracture of prestressed steel strands of prefabricated beams, comprising a rectangular box 1 with a side opening, a main shaft 2, a buffer spiral tube 3, and a hoop 4 installed on the main shaft 2. The five walls of the rectangular box 1 are made of 3-5mm steel plates. The main shaft 2 is made of a steel pipe, and the diameter of the steel pipe is 3-5cm. The main shaft 2 is vertically installed between the upper and lower surfaces inside the rectangular box 1 through two seat bearings 5. The buffer spiral tube 3 is connected to the hoop 4 as a whole through a plurality of connectors 6. The connector 6 is made of a steel pipe, and the diameter of the steel pipe is 1-3cm.

[0029] The buffer spiral tube 3 comprises a spiral tube section 31 and a bell mouth section 32 fixed to the lower end of the spiral tube section 31. The wall thickness of the spiral tube section 31 is 3-5 mm, and the spiral tube section 31 spirals upward around the main shaft 2.

[0030] The broken steel strand enters from the bell mouth section 32 and then spirals upward along the spiral pipe section 31. Under the impact force of the broken steel strand, the buffer spiral pipe 3, i.e., the main shaft 2, will rotate. By decomposing the kinetic energy of the steel strand into the gravitational potential energy of the steel strand and the kinetic energy of the buffer steel pipe and the main shaft, a flexible buffer device is formed, breaking the traditional concept of rigid protection and greatly improving the buffer efficiency.

[0031] At least four self-locking universal wheels 7 are installed at the bottom of the rectangular box 1, which can be turned and locked at will, making it convenient to move around the venue.

[0032] A specific application of this embodiment is: place the buffer device on site, loosen the clamp 4, move it up and down, adjust the height, and align the bell mouth of the bell mouth section 32 with the steel strand. When the steel strand breaks and flies out, it flies into the buffer steel pipe from the bell mouth, and after contacting the inner wall of the spiral pipe section 31, it flies vertically upward along the inner spiral of the spiral pipe section 31. Because the steel strand contacts the inner wall of the spiral pipe section 31, the spiral pipe section 31 will drive the main shaft to rotate and perform planar circular motion. The kinetic energy of the steel strand is converted into the gravitational potential energy obtained after the steel strand spirals vertically upward, and the kinetic energy obtained by the circular motion of the buffer spiral tube 3 and the main shaft 2. The rectangular box 1 plays a secondary buffering role, and can also play a buffering role if the steel strand passes through the spiral pipe section 31.

[0033] In the description of this specification, the description with reference to the terms "one embodiment", "example", "specific example", etc. means that the specific features, structures, materials or characteristics described in conjunction with the embodiment or example are included in at least one embodiment or example of the utility model. In this specification, the schematic representation of the above terms does not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials or characteristics described can be combined in any one or more embodiments or examples in a suitable manner.

[0034] The preferred embodiments of the utility model disclosed above are only used to help explain the utility model. The preferred embodiments do not describe all the details in detail, nor do they limit the utility model to the specific implementation methods described. Obviously, many modifications and changes can be made according to the content of this specification. This specification selects and specifically describes these embodiments in order to better explain the principles and practical applications of the utility model, so that technicians in the relevant technical field can well understand and use the utility model. The utility model is limited only by the claims and their full scope and equivalents.

Claims

1. A buffer device for the tension fracture of prestressed steel strands in prefabricated beams, characterized in that: It comprises a rectangular box body (1) with a side opening, a main shaft (2), a buffer spiral tube (3), and a clamp (4) installed on the main shaft (2); The main shaft (2) is vertically mounted between the upper and lower surfaces inside the rectangular box (1) via two seat bearings (5); The buffer spiral tube (3) is connected to the clamp (4) as a whole via a plurality of connecting pieces (6); The buffer spiral tube (3) comprises a spiral tube section (31) and a bell mouth section (32) fixed to the lower end of the spiral tube section (31).

2. The buffer device for the tension fracture of prestressed steel strands of prefabricated beams according to claim 1 is characterized in that: At least four self-locking universal wheels (7) are installed at the bottom of the rectangular box (1).

3. The buffer device for preventing the prestressed steel strands from being stretched and broken according to claim 1 is characterized in that: The connecting piece (6) is a steel pipe, and the diameter of the steel pipe is 1-3 cm.

4. The buffer device for preventing the prestressed steel strands from being stretched and broken according to claim 1 is characterized in that: The main shaft (2) is a steel pipe, and the diameter of the steel pipe is 3-5 cm.

5. The buffer device for preventing the prestressed steel strands from being stretched and broken according to claim 1 is characterized in that: The five walls of the rectangular box (1) are all made of 3-5 mm steel plates.

6. The buffer device for preventing the prestressed steel strands from being stretched and broken according to claim 1 is characterized in that: The wall thickness of the spiral tube section (31) is 3-5 mm, and the spiral tube section (31) spirals upward around the main axis (2).

Images