A reinforcement device and construction method for precise supplementary tensioning of external prestress

Abstract

The present invention discloses a reinforcement device and construction method for precise supplementary tensioning of external prestress. The device includes an anchoring structure, a supplementary tensioning structure, and prestressing tendons. The anchoring structures are symmetrically fixed at the bottom of the concrete beam. The supplementary tensioning structure is fixed on the beam and placed between the anchoring structures. Both ends of the prestressing tendons pass through the anchoring structures and pass between the supplementary tensioning structures. The supplementary tensioning structure includes a round rod, a scroll worm that moves up and down on the round rod, a duct assembly for the prestressing tendons to pass through, and a stress control assembly placed on the round rod. The rotation circumference of the stress control assembly is equal to the lifting height of the scroll worm. The construction method includes installing the anchoring structure, fixing the supplementary tensioning structure, performing initial tensioning on the prestressing tendons, fixing the supplementary tensioning structure and the prestressing tendons at the beam bottom, and making up the prestress through the supplementary tensioning structure. The present invention aims to provide a prestress reinforcement device that can be reused and can precisely control the supplementary tensioning force.

Description

Technical Field

[0001] The present invention relates to the technical field of concrete structure reinforcement, and particularly relates to a reinforcement device and construction method for precise supplementary tensioning of external prestress. Background Art

[0002] With the rapid development of China's social economy, the rapid increase in traffic volume will accelerate the deterioration rate of prestressed concrete beams. In addition, during the service process of bridges, due to the erosion of the external environment, the prestressed tendons inside the structure will inevitably rust, resulting in concrete cracking and internal prestress loss. To avoid excessive impact on the service performance and safety performance of bridges, scientific and effective reinforcement methods must be adopted to ensure the service safety of bridge structures.

[0003] The external prestress reinforcement technology is a commonly used reinforcement method. It anchors and connects a tie rod or strut arranged outside the beam to the reinforced beam body, and then applies prestress to improve the internal force distribution of the structure. Currently, the commonly used external prestress reinforcement technologies include the external prestressed steel wire bundle reinforcement method and the under-supported prestressed tie rod reinforcement method. When using the external prestressed steel wire bundle reinforcement method to reinforce with prestressed steel wire bundles, since setting and tensioning the steel wire bundles will increase the compressive stress on the upper edge of the beam end, it is easy to cause the concrete on the upper edge of the beam end to crack due to insufficient compressive strength. The under-supported prestressed tie rod reinforcement method can be divided into prestressed tie rod reinforcement and prestressed strut reinforcement. Among them, the prestressed tie rod reinforcement method is applicable to flexural members, while the prestressed strut reinforcement method is mostly used to improve the bearing capacity of axially compressed and eccentrically compressed reinforced concrete columns.

[0004] Most of the existing prestress reinforcement methods are one-time construction. For example, in the patent with the patent number 202120050815.6 and the patent name "A bonded prestress structure for hollow slab bridge reinforcement", it is recorded that: an anchoring tooth plate is installed at the bottom of the hollow slab of the bonded prestress structure; Φj8.6 three-strand steel strands are installed and tensioned; shear reinforcement is set at the bottom of the slab and wire mesh is installed; high-strength tensile mortar is sprayed in batches in the prestressed tendon and tooth plate area. After the construction is completed, the prestressed tendons will relax, and it is difficult to perform supplementary tensioning again or the supplementary tensioning construction is difficult. In addition, the existing external prestress reinforcement technology is difficult to accurately control the magnitude of prestress, and it is easy to have the situation of too small or too large tensioned prestress. Therefore, it is urgent to develop an external prestress reinforcement device that can effectively control the magnitude of prestress and has the ability of multiple supplementary tensionings. Summary of the Invention

[0005] The purpose of the invention is to provide a reinforcement device and construction method for precise supplementary tensioning of external prestress, which solves the problems that the traditional external prestress cannot accurately control the magnitude of the tensioning force and it is difficult to perform supplementary tensioning again after the tensioning is completed.

[0006] The present invention is implemented as follows. A reinforcement device for precise supplementary tensioning of external prestress, the reinforcement device includes an anchoring structure, a prestressing tendon, and a supplementary tensioning structure.

[0007] The anchoring structure is fixed at the bottom of the concrete beam and is symmetrically arranged. The supplementary tensioning structure is fixed on the concrete beam and is placed between the anchoring structures. Both ends of the prestressing tendon pass through the anchoring structure, and the prestressing tendon passes between the supplementary tensioning structures.

[0008] The supplementary tensioning structure includes a round rod, a scroll worm that moves up and down sleeved on the round rod, a hole component that is symmetrically arranged on the scroll worm and through which the prestressing tendon passes, and a stress control component arranged on the round rod. The stress control component includes a rotating turbine, and the rotating turbine meshes with the scroll worm. The rotation circumference of the rotating turbine is equal to the lifting height of the scroll worm.

[0009] Through the combination of the scroll worm and the stress control component, the distance between the prestressing tendon and the bottom of the concrete beam is precisely controlled, and further the magnitude of the prestress supplementary tensioning is precisely controlled, so as to achieve the problem of continuously and precisely compensating for the prestress loss of prestressed concrete.

[0010] The round rod is a solid round rod, and the round rod is directly fixed at the bottom of the concrete beam through a chassis.

[0011] A further technical solution of the present invention is: The stress control component further includes two vertical plates, a cylinder passing between the vertical plates, and a dial sleeved on the cylinder. The rotating turbine is placed between the two vertical plates. The cylinder passes through the rotating turbine and is fixedly connected to the rotating turbine. The cylinder is provided with a pry hole.

[0012] A further technical solution of the present invention is: Both ends of the vertical plate are respectively connected to the top and bottom of the round rod through fixing rings.

[0013] A further technical solution of the present invention is: The outer side of the round rod is provided with holes, and round beads are arranged in the holes. The round beads roll in place, and the scroll worm can move up and down on the round rod through the round beads.

[0014] The holes include several groups and are vertically arranged. The round beads are solid round beads, and the round beads can roll in place to ensure an appropriate gap and effective sliding between the solid round rod and the hollow scroll worm.

[0015] A further technical solution of the present invention is: The outer side of the round rod is provided with ratchet teeth, and a one-way rack that cooperates with the ratchet teeth is arranged on the inner wall of the scroll worm.

[0016] There are two ratchets, and rubber is provided at the ends to ensure that the ratchets are always in contact with the inside of the scroll worm; the cooperation of the ratchets and the one-way rack is adopted to effectively prevent the scroll worm from returning after the supplementary tensioning is completed.

[0017] A further technical solution of the present invention is that: the duct assembly includes a body with a duct opened therein, an elastic rubber placed above the inside of the duct, and a grooved ball placed inside the duct and connected to the lower part of the elastic rubber, and the prestressed tendon passes through the groove at the bottom of the grooved ball.

[0018] The duct through which the prestressed tendon passes adopts a combination of elastic rubber and a perforated grooved ball, effectively reducing the stress concentration generated by the duct squeezing the prestressed tendon.

[0019] A further technical solution of the present invention is that: the anchoring structure includes an anchor pad plate and bolts and nuts for fixing the anchor pad plate on the concrete beam, and the prestressed tendon passes through the anchor pad plate and is fixed by a wedge.

[0020] A further technical solution of the present invention is that: the anchor pad plate includes an anchor base plate and an anchor plate, the anchor plate is fixed to the concrete beam through the bolts and nuts, and the prestressed tendon passes through the anchor plate and is fixed by the wedge.

[0021] The present invention also provides a construction method for a reinforcement device for precise supplementary tensioning of external prestress. The reinforcement device includes the reinforcement device as described above. The construction method includes the following steps:

[0022] Step 1: Grind at the position corresponding to the installation of the anchoring structure on the concrete beam until the coarse aggregate is exposed, and drill holes for fixing the anchoring structure on the concrete beam where the anchoring structure is installed;

[0023] Step 2: Install the anchoring structure so that the anchoring structure is fixed to the concrete beam;

[0024] Step 3: Pass one end of the prestressed tendon through the anchoring structure and fix it. The other end of the prestressed tendon passes through the duct assembly of the supplementary tensioning structure, adjust the position of the supplementary tensioning structure on the concrete beam, and fix the supplementary tensioning structure;

[0025] Step 4: Tension the prestressed tendon so that the prestressed tendon is in a taut state, pass the prestressed tendon at the unfixed end through another anchoring structure and fix it, and perform initial tensioning on the prestressed tendon through an externally connected tensioning device;

[0026] Step 5: After the initial tensioning is completed, remove the tensioning device, and fix the supplementary tensioning structure and the prestressed tendon at the bottom of the concrete beam;

[0027] Step 6: When the prestressed tendon in the concrete beam undergoes prestress relaxation, the prestress can be compensated through the supplementary tensioning structure.

[0028] A further technical solution of the present invention is as follows: There are two supplementary tensioning structures. After the initial tensioning is completed in Step 5, record the initial tensile force F, measure the distance h1 from the prestressed tendon at the tensioning device end to the bottom of the beam, and the distance h2 from the prestressed tendons of the two end anchoring devices to the bottom of the beam. Measure the horizontal distance B between the supplementary tensioning structure and the anchoring end to obtain the initial length l of 1 / 2 of the prestressed tendon.

[0029] In Step 6, if the required supplementary tensile prestress magnitude is ΔF, then the height by which the scroll worm of the supplementary tensioning structure descends where A is the cross-sectional area of the steel bar after re-tensioning, and E is the elastic modulus of the prestressed tendon. Operate the supplementary tensioning structure and read the reading on the corresponding stress control component to obtain the height Δh by which the scroll screw descends, thereby controlling the precise tensioning of the supplementary tensioning structure.

[0030] A further technical solution of the present invention is as follows: In Step 1, at the position where the prestressed tendon anchoring structure is installed, grind the concrete beam body flat, and at the same time grind off the surface mortar layer until the coarse aggregate is exposed. Drill holes corresponding to the bolt holes on the anchoring structure in the concrete beam where the anchoring structure is installed; remove the dust from the bolt holes and the concrete grinding surface.

[0031] A further technical solution of the present invention is as follows: In Step 2, first install the anchor pad plate in the anchoring structure, and then install the corresponding bolts and tighten the nuts.

[0032] A further technical solution of the present invention is as follows: In Step 3, pass one end of the prestressed tendon through the hole of the anchor pad plate in the anchoring structure and fix it on the anchoring plate through the wedge in the anchoring structure; pass the other end of the prestressed tendon through the hole of the supplementary tensioning structure, and the two prestressed tendons pass through the supplementary tensioning structure in sequence. After the prestressed tendon passes through the hole, adjust the position of the supplementary tensioning structure at the bottom of the beam. After adjusting the position, mark the installation position, grind and drill holes. Then move the supplementary tensioning structure to the marked position again and install bolts to fix the supplementary tensioning structure at the bottom of the beam.

[0033] A further technical solution of the present invention is as follows: In Step 4, keep the prestressed tendon in a taut state, pass the unfixed end of the prestressed tendon through the anchoring structure at the other end, connect and fix the prestressed tendon with the wedge in the anchoring structure, and use a hydraulic tensioning machine to connect one end of the prestressed tendon for initial tensioning.

[0034] A further technical solution of the present invention is as follows: The specific operation method for operating the supplementary tensioning structure in Step 6 is as follows: Insert a crowbar into the crowbar hole in the cylinder of the stress control component, rotate the crowbar, and read the reading on the dial of the corresponding stress control component. The circumference of the rotation of the dial is the height Δh by which the scroll screw descends, thereby controlling the precise tensioning of the tensioning device.

[0035] Beneficial effects of the present invention: The present invention provides an external prestressed reinforcement device which is permanently installed on a prestressed concrete beam. The device accurately controls the distance between the prestressed tendons and the bottom of the concrete beam through the combination of a vortex worm and a stress control component, thereby accurately controlling the size of the prestressed reinforcement, thereby achieving the problem of sustainable and accurate compensation for the prestress loss of the prestressed concrete, thereby solving the problem of one-time tensioning of the traditional external prestressed concrete and difficulty in tensioning.

[0036] Elastic rubber and round balls are arranged in the hole of the hole assembly, and the prestressed tendons pass through the round balls. During the pulling process of the prestressed tendons, the round balls can move slightly and cooperate with the elastic rubber, thus avoiding stress concentration and effectively extending the service performance of the prestressed beam;

[0037] The ratchet structure is used inside the tensioning structure to effectively prevent the worm from returning to its original position after the tensioning is completed, thus ensuring the stability of the reinforced concrete beam.

[0038] According to the method of the present invention, the force can be further transmitted to the beam during the tensioning process, thereby reducing the mid-span deflection; the construction cost is low, and the construction is simple and convenient. BRIEF DESCRIPTION OF THE DRAWINGS

[0039] Figure 1 This is a front view of a reinforcement device for external prestressed precise tensioning provided by the present invention connected to a concrete beam;

[0040] Figure 2 is a structural schematic diagram of the anchoring structure provided by the present invention;

[0041] Figure 3 is a front view of the tensioning structure provided by the present invention;

[0042] Figure 4 is a side view of the tensioning structure provided by the present invention;

[0043] Figure 5 It is a schematic diagram of the structure of the internal connection between the round rod and the vortex worm provided by the present invention;

[0044] Figure 6 It is a schematic diagram of the internal structure of the channel in the channel assembly provided by the present invention;

[0045] Figure 7 It is a schematic structural diagram of a grooved round ball provided by the present invention;

[0046] Figure 8 It is a structural schematic diagram of the connection between the prestressed tendons and the tensioning structure provided by the present invention.

[0047] Reference numerals: 1. concrete beam; 2. anchoring structure; 201. bolt; 202. nut; 203. wedge; 204. anchor pad plate; 3. prestressed tendon; 4. supplementary tensioning structure; 401. round bar; 402. scroll worm; 403. fixing ring; 404. rotating turbine; 405. vertical plate; 406. cylinder; 407. duct assembly; 408. ratchet tooth; 409. rubber; 410. ball; 411. dial; 407-1. grooved ball; 407-2. elastic rubber; 407-3. body. Detailed implementation mode

[0048] The following uses specific specific examples to illustrate the implementation mode of the present invention. Those skilled in the art can easily understand other advantages and effects of the present invention from the content disclosed in this specification. The present invention can also be implemented or applied through other different specific implementation modes. Various details in this specification can also be modified or changed based on different viewpoints and applications without departing from the spirit of the present invention.

[0049] It should be noted that the structures, proportions, sizes, etc. shown in the drawings of this specification are only used to cooperate with the content disclosed in the specification for those skilled in this technology to understand and read, and are not used to limit the limiting conditions under which the present invention can be implemented. Therefore, they do not have technical substance. Any modification of the structure, change of the proportional relationship, or adjustment of the size should still fall within the scope that can be covered by the technical content disclosed in the present invention without affecting the effects that the present invention can produce and the purposes that can be achieved. At the same time, the terms such as "upper", "lower", "left", "right", "middle", and "one" cited in this specification are only for the convenience of clear description and are not used to limit the scope under which the present invention can be implemented. The change or adjustment of their relative relationships should also be regarded as the scope under which the present invention can be implemented without substantial change in technical content.

[0050] Example 1:

[0051] Figures 1-7 There is shown a reinforcement device for precise supplementary tensioning of external prestress. The reinforcement device includes an anchoring structure 2, a prestressed tendon 3, and a supplementary tensioning structure 4.

[0052] The anchoring structure 2 is fixed at the bottom of the concrete beam 1 and is symmetrically arranged. The supplementary tensioning structure 4 is fixed on the concrete beam 1 and is placed between the anchoring structures 2. Both ends of the prestressed tendon 3 pass through the anchoring structure 2, and the prestressed tendon 3 passes between the supplementary tensioning structures 4.

[0053] The supplementary tensioning structure 4 includes a round rod 401, a scroll worm 402 sleeved on the round rod 401 and moving up and down, a duct assembly 407 symmetrically arranged on the scroll worm 402 and through which the prestressed tendon 3 passes, and a stress control assembly arranged on the round rod 401. The stress control assembly includes a rotating turbine 404, the rotating turbine 404 meshes with the scroll worm 402, and the rotation circumference of the rotating turbine 404 is equal to the lifting height of the scroll worm 402.

[0054] Through the combination of the scroll worm and the stress control assembly, the distance between the prestressed tendon and the bottom of the concrete beam is precisely controlled, and then the size of the prestress supplementary tensioning is precisely controlled, so as to achieve the problem of continuously and precisely compensating for the prestress loss of the prestressed concrete.

[0055] As a preferred embodiment, the round rod is a solid round rod, and the round rod is directly fixed to the bottom of the concrete beam through a chassis.

[0056] In this embodiment, the stress control assembly further includes two vertical plates 405, a cylinder 406 passing between the vertical plates 405, and a scale disk 411 sleeved on the cylinder 406. The rotating turbine 404 is arranged between the two vertical plates 405. The cylinder 406 passes through the rotating turbine 404 and is fixedly connected to the rotating turbine 404. The cylinder 406 is provided with a pry hole.

[0057] In this embodiment, the two ends of the vertical plate 405 are respectively connected to the top and bottom of the round rod 401 through fixing rings 403.

[0058] In this embodiment, holes are provided on the outer side of the round rod 401, round beads 410 are arranged in the holes, the round beads 410 roll in place, and the scroll worm 402 can move up and down on the round rod 401 through the round beads 410.

[0059] The holes include several groups and are arranged vertically. The round beads are solid round beads and can roll in place, ensuring an appropriate gap and effective sliding between the solid round rod and the hollow scroll worm.

[0060] In this embodiment, ratchet teeth 408 are provided on the outer circumference of the round rod 401, and a one-way rack matching with the ratchet teeth 408 is provided on the inner wall of the scroll worm 402.

[0061] As a preferred embodiment, there are two ratchet teeth, and rubber 409 is provided at the end of the ratchet teeth 408 to ensure that the ratchet teeth are always in contact with the inside of the scroll worm; the cooperation of the ratchet teeth and the one-way rack effectively prevents the scroll worm from returning after the supplementary tensioning is completed.

[0062] In this embodiment, the duct assembly 407 includes a body 407-3 with a duct formed therein, an elastic rubber 407-2 disposed above the interior of the duct, and a grooved ball 407-1 disposed within the duct and connected to the lower portion of the elastic rubber 407-2. The prestressing tendon 3 passes through the groove at the bottom of the grooved ball 407-1.

[0063] The duct through which the prestressing tendon passes adopts a combination of elastic rubber and a perforated grooved ball, effectively reducing the stress concentration generated by the duct squeezing the prestressing tendon.

[0064] In this embodiment, the anchoring structure 2 includes an anchor plate block 204, bolts 201 and nuts 202 for fixing the anchor plate block 204 to the concrete beam 1. The prestressing tendon 3 passes through the anchor plate block 204 and is fixed by wedge-shaped grip 203.

[0065] In this embodiment, the anchor plate block 204 includes an anchor plate and an anchor block. The anchor block is fixed to the concrete beam 1 by the bolts 201 and nuts 202. The prestressing tendon 3 passes through the anchor block and is fixed by the wedge-shaped grip 203.

[0066] Embodiment 2:

[0067] A construction method for a reinforcement device for precise supplementary tensioning of external prestressing. The reinforcement device includes the reinforcement device described in Embodiment 1. The construction method includes the following steps:

[0068] Step 1: Grind the position on the concrete beam corresponding to the installation of the anchoring structure until the coarse aggregate is exposed, and drill holes for fixing the anchoring structure on the concrete beam where the anchoring structure is to be installed.

[0069] Step 2: Install the anchoring structure so that the anchoring structure is fixed to the concrete beam.

[0070] Step 3: Pass one end of the prestressing tendon through the anchoring structure and fix it. Pass the other end of the prestressing tendon through the duct assembly of the supplementary tensioning structure, adjust the position of the supplementary tensioning structure on the concrete beam, and fix the supplementary tensioning structure.

[0071] Step 4: Tension the prestressing tendon so that the prestressing tendon remains in a taut state, pass the prestressing tendon at the unfixed end through another anchoring structure and fix it, and perform initial tensioning on the prestressing tendon through a tensioning device.

[0072] Step 5: After the initial tensioning is completed, remove the tensioning device, and fix the supplementary tensioning structure and the prestressing tendon to the bottom of the concrete beam.

[0073] Step 6: When prestress relaxation occurs in the prestressing tendon in the concrete beam, the prestress can be compensated through the supplementary tensioning structure.

[0074] In this embodiment, there are two supplementary tensioning structures. After the initial tensioning in Step 5 is completed, record the initial tension force F, measure the distance h1 from the prestressed tendon at the tensioning device end to the bottom of the beam, and the distances h2 from the prestressed tendons at the two anchoring devices to the bottom of the beam. Measure the horizontal distance B between the supplementary tensioning structure and the anchoring end to obtain the initial length l of 1 / 2 of the prestressed tendon; as Figure 8 shown;

[0075] In Step 6, if the required supplementary tension prestress magnitude is ΔF, then the height by which the scroll worm of the supplementary tensioning structure descends where A is the cross-sectional area of the steel bar after re-tensioning, and E is the elastic modulus of the prestressed tendon. Operate the supplementary tensioning structure and read the readings on the corresponding stress control component to obtain the height Δh by which the scroll screw descends, thereby controlling the precise tensioning of the supplementary tensioning structure.

[0076] In this embodiment, in Step 1, at the position where the prestressed tendon anchoring structure is installed, grind the concrete beam body flat, and at the same time grind off the surface mortar layer until the coarse aggregate is exposed. Drill holes corresponding to the bolt holes on the anchoring structure in the concrete beam where the anchoring structure is installed; remove the dust from the bolt holes and the concrete grinding surface;

[0077] In this embodiment, in Step 2, first install the anchor pad plate in the anchoring structure, and then install the corresponding bolts and tighten the nuts.

[0078] In this embodiment, in Step 3, pass one end of the prestressed tendon through the hole of the anchor pad plate in the anchoring structure and fix it on the anchoring plate through the wedge-shaped clip in the anchoring structure; pass the other end of the prestressed tendon through the hole of the supplementary tensioning structure, and the two prestressed tendons pass through the supplementary tensioning structure in sequence. After the prestressed tendon passes through the hole, adjust the position of the supplementary tensioning structure at the bottom of the beam. After adjusting the position, mark the installation position, grind and drill holes. Then move the supplementary tensioning structure to the marked position again and install bolts to fix the supplementary tensioning structure at the bottom of the beam.

[0079] In this embodiment, in Step 4, keep the prestressed tendon in a taut state, pass the unfixed end of the prestressed tendon through the anchoring structure at the other end, connect and fix the prestressed tendon with the wedge-shaped clip in the anchoring structure, and connect one end of the prestressed tendon with a hydraulic tensioning machine for initial tensioning.

[0080] In this embodiment, the specific operation method for operating the supplementary tensioning structure in Step 6 is: insert a crowbar into the crowbar hole in the cylinder of the stress control component, rotate the crowbar, and read the readings on the dial of the corresponding stress control component. The circumference by which the dial rotates is the height Δh by which the scroll screw descends, thereby controlling the precise tensioning of the tensioning device.

[0081] The above are only the preferred embodiments of the present invention and are not intended to limit the present invention. Any modifications, equivalent replacements, improvements, etc. made within the spirit and principle of the present invention shall be included within the protection scope of the present invention.

Claims

1. A reinforcement device for precise supplementary tensioning of external prestress, characterized in that: The reinforcement device includes an anchoring structure (2), a prestressed tendon (3), and a supplementary tensioning structure (4). The anchoring structure (2) is used to be fixed at the bottom of the concrete beam (1) and is symmetrically arranged. The supplementary tensioning structure (4) is used to be fixed on the concrete beam (1) and is placed between the anchoring structures (2). Both ends of the prestressed tendon (3) pass through the anchoring structure (2), and the prestressed tendon (3) passes between the supplementary tensioning structures (4). The supplementary tensioning structure (4) includes a round rod (401), a scroll worm (402) sleeved on the round rod (401) and moving up and down, a hole channel assembly (407) symmetrically arranged on the scroll worm (402) and for the prestressed tendon (3) to pass through, and a stress control assembly placed on the round rod (401). The stress control assembly includes a rotating turbine (404), and the rotating turbine (404) meshes with the scroll worm (402). The rotation circumference of the rotating turbine (404) is equal to the lifting height of the scroll worm (402). The stress control assembly further includes two vertical plates (405), a cylinder (406) passing between the vertical plates (405), and a dial (411) sleeved on the cylinder (406). The rotating turbine (404) is placed between the two vertical plates (405). The cylinder (406) passes through the rotating turbine (404), and the cylinder (406) is fixedly connected to the rotating turbine (404). The cylinder (406) is provided with a pry hole. Both ends of the vertical plate (405) are respectively connected to the top and bottom of the round rod (401) through fixing rings (403). Through the combination of the scroll worm and the stress control assembly, the distance between the prestressed tendon and the bottom of the concrete beam is accurately controlled, and then the size of the supplementary prestress tensioning is accurately controlled, so as to achieve the problem of continuously and accurately compensating for the prestress loss of prestressed concrete.

2. The reinforcement device for precise supplementary tensioning of external prestress according to claim 1, characterized in that, Holes are provided on the outer side of the round rod (401), and round beads (410) are arranged in the holes. The round beads (410) roll in place, and the scroll worm (402) can move up and down on the round rod (401) through the round beads (410).

3. The reinforcement device for precise supplementary tensioning of external prestress according to claim 1, wherein Ratchet teeth (408) are provided on the outer circumference of the round rod (401), and a one-way rack cooperating with the ratchet teeth (408) is provided on the inner wall of the scroll worm (402).

4. The reinforcement device for precise supplementary tensioning of external prestress according to claim 1, characterized in that, The hole channel assembly (407) includes a body (407-3) provided with a hole channel, an elastic rubber (407-2) placed above the inside of the hole channel, and a grooved round bead (407-1) placed inside the hole channel and connected to the lower part of the elastic rubber (407-2). The prestressed tendon (3) passes through the groove at the bottom of the grooved round bead (407-1).

5. The reinforcement device for precise supplementary tensioning of external prestress according to claim 1, characterized in that, The anchoring structure (2) includes an anchor pad plate (204), bolts (201) and nuts (202) for fixing the anchor pad plate (204) on the concrete beam (1). The prestressed tendon (3) passes through the anchor pad plate (204) and is fixed by wedge-shaped jaws (203).

6. The reinforcement device for precise supplementary tensioning of external prestress according to claim 5, characterized in that, The anchor pad plate block (204) includes an anchor backing plate and an anchor block. The anchor block is fixed to the concrete beam (1) by the bolts (201) and nuts (202). The prestressed tendon (3) passes through the anchor block and is fixed by the wedge grips (203).

7. Construction method of a reinforcement device for precise supplementary tensioning of external prestress, characterized in that, The reinforcement device includes the reinforcement device according to any one of claims 1-6. The construction method includes the following steps: Step 1: Grind at the position corresponding to the installation of the anchoring structure on the concrete beam until the coarse aggregate is exposed, and drill holes for fixing the anchoring structure on the concrete beam; Step 2: Install the anchoring structure so that the anchoring structure is fixed to the concrete beam; Step 3: Pass one end of the prestressed tendon through the anchoring structure and fix it. The other end of the prestressed tendon passes through the duct assembly of the supplementary tensioning structure. Adjust the position of the supplementary tensioning structure on the concrete beam and fix the supplementary tensioning structure; Step 4: Tension the prestressed tendon so that the prestressed tendon remains in a taut state, pass the prestressed tendon at the unfixed end through another anchoring structure and fix it, and perform initial tensioning on the prestressed tendon; Step 5: After the initial tensioning is completed, the supplementary tensioning structure and the prestressed tendon are fixed to the bottom of the concrete beam; Step 6: When prestress relaxation occurs in the prestressed tendon in the concrete beam, the prestress can be compensated by the supplementary tensioning structure.

8. The construction method of a reinforcement device for precise supplementary tensioning of external prestress according to claim 7, characterized in that, There are two supplementary tensioning structures. After the initial tensioning in Step 5 is completed, record the initial tension F, measure the distance h1 from the prestressed tendon at the tensioning device end to the beam bottom, the distance h2 from the prestressed tendons of the two end anchoring devices to the beam bottom, and measure the horizontal distance B between the supplementary tensioning structure and the anchoring end to obtain the initial length l of 1 / 2 of the prestressed tendon; In step six, if the known additional prestress magnitude requirement is ΔF, the height by which the additional tensioning structure's scroll worm descends where A is the cross-sectional area of the steel bar after re-tensioning, E is the elastic modulus of the prestressed tendon. Operate the additional tensioning structure, read the reading on the corresponding stress control component, and obtain the height Δh by which the scroll screw descends, thereby controlling the precise tensioning of the additional tensioning structure.

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