A device and method for separating steel bars from reinforced concrete structure

Abstract

The present invention discloses a device and method for removing steel bars from a reinforced concrete structure. The device includes: a periodic load loading device and a hot and cold cycle device, which are arranged on the reinforced concrete structure. The periodic load loading device is used to load periodic loads on the reinforced concrete structure, and the hot and cold cycle device is used to perform hot and cold cycle treatment on the reinforced concrete structure to destroy the bite between the steel bars and concrete in the reinforced concrete structure; a tensioning device is arranged at both ends of the steel bars in the reinforced concrete structure to pull out the steel bars. First, the two ends of the reinforced concrete structure are fixed, and the two ends of the reinforced concrete structure are treated to expose a certain length of steel bars at both ends; the reinforced concrete structure is loaded with periodic loads, and then the steel bars are subjected to hot and cold cycle treatment to destroy the bite between the concrete and the steel bars contact surface, and then tensioning force is alternately applied to the exposed steel bars to pull out the steel bars, thereby reducing the breakage rate of the steel bars and effectively recycling the steel bars.

Description

Technical Field

[0001] The invention belongs to the technical field of steel bar recycling and relates to a device and method for separating steel bars from a reinforced concrete structure. Background Art

[0002] At present, the construction of houses and other infrastructure projects is approaching saturation. Now we are facing the demolition and reconstruction of old houses and other infrastructure projects. The demolition of reinforced concrete structures will produce a large amount of scrap steel bars. Therefore, it is necessary to recycle scrap steel bars from the demolished reinforced concrete structures. The existing methods of recycling steel bars from reinforced concrete mostly use machines to violently crush and cut concrete, so that the steel bars in the reinforced concrete are exposed to achieve the recycling effect. However, these methods will have the following disadvantages:

[0003] 1. It will generate huge noise, affecting the surrounding residents. Construction cannot be carried out at night, which is not conducive to the construction period requirements;

[0004] 2. It will generate a lot of smoke and dust, which will damage the environment and have a huge impact on the health of the workers;

[0005] 3. The breakage rate of steel bars in reinforced concrete is relatively high. Summary of the invention

[0006] The purpose of the embodiments of the present invention is to provide a device and method for removing steel bars from reinforced concrete structures, so as to solve the problem that the existing method of recovering steel bars from reinforced concrete structures by violently crushing and cutting concrete will generate huge noise and a large amount of smoke and dust, and the steel bar breakage rate is relatively high.

[0007] The technical solution adopted in the embodiment of the present invention is: a device for removing steel bars from a reinforced concrete structure, characterized in that it comprises:

[0008] The periodic load loading device and the hot and cold cycle device are arranged on the reinforced concrete structure. The periodic load loading device is used to load the periodic load on the reinforced concrete structure. The hot and cold cycle device is used to perform hot and cold cycle treatment on the reinforced concrete structure to destroy the bite between the steel bars and the concrete in the reinforced concrete structure.

[0009] The tensioning device is installed at both ends of the steel bars in the reinforced concrete structure and is used to pull the steel bars.

[0010] Furthermore, the hot and cold cycle device comprises:

[0011] An electric heater is arranged on the exposed steel bars at both ends of the reinforced concrete structure to heat the steel bars;

[0012] An electric heating controller, which is electrically connected to the electric heater and is used to control the heating process of the electric heater;

[0013] The insulation sleeve is installed on the reinforced concrete structure. The reinforced concrete structure is quickly cooled by filling it with flowing cooling medium, thereby indirectly cooling the steel bars in the reinforced concrete structure.

[0014] Furthermore, the periodic load loading device comprises:

[0015] Fixed seat, both ends of the reinforced concrete structure are fixed on corresponding fixed seats respectively;

[0016] A loading beam, the loading beam is arranged above the reinforced concrete structure, and a compression column located above the reinforced concrete structure is arranged at the bottom of the loading beam;

[0017] Cyclic load controller,The cyclic load controller is used to control the movement of the loading beam to control the cyclic loading process of the compression column.

[0018] Furthermore, the fixing seat includes a base and a pressure plate, the base and the pressure plate are provided with mounting holes, the end of the reinforced concrete structure is placed on the base, and the pressure plate is placed on the reinforced concrete structure, and the base and the pressure plate are detachably connected by bolts passing through the mounting holes thereon and located on the side of the reinforced concrete structure.

[0019] Furthermore, a vertical threaded column is provided on the top of the pressure plate of each fixed seat, the bottom of the threaded column is rotatably connected to the pressure plate, and both ends of the loading beam are respectively threadedly connected to the corresponding threaded columns, and the two threaded columns rotate synchronously to drive the loading beam and the pressure column to move up and down;

[0020] The periodic load controller is electrically connected to the servo system of the two threaded columns, and controls the rotation process of the two threaded columns by controlling the working process of the servo system of the two threaded columns, thereby controlling the periodic load loading process of the loading beam and the pressure column;

[0021] A first pressure sensor is installed at the bottom of the pressure column. The first pressure sensor is used to detect the axial force applied by the loading beam and the pressure column and feed it back to the periodic load controller. The periodic load controller controls the moving speed of the loading beam, i.e. the loading speed, in a closed-loop manner according to the axial force detected by the first pressure sensor.

[0022] Furthermore, the tensioning device comprises:

[0023] Tensioning pedestal, on which the reinforced concrete structure is placed horizontally;

[0024] Reinforced concrete piers, wherein two reinforced concrete piers are arranged on the tensioning pedestal at a certain distance, the distance between the reinforced concrete piers is greater than the length of the reinforced concrete structure, and first steel bar through-holes are arranged on both reinforced concrete piers;

[0025] A crossbeam, each crossbeam is arranged on the outside of the corresponding reinforced concrete pier, and a second steel bar through-hole is arranged on the crossbeam. The steel bars at any end of the reinforced concrete structure pass through the corresponding first steel bar through-hole and second steel bar through-hole in sequence, and are detachably fixedly connected to the crossbeam through a steel bar fixing structure;

[0026] Jacks, each jack is horizontally fixed on a corresponding reinforced concrete pier, and its loading end is fixedly connected to the crossbeam;

[0027] Tensioning controller: The tensioning controller is used to control the extension process of the jack to achieve control of the tensioning force.

[0028] Furthermore, a second pressure sensor is provided at the extension end of the jack, and the second pressure sensor feeds back the detected pressure value to the tensioning controller in real time. The tensioning controller is electrically connected to the jack, and controls the extension speed of the jack in a closed loop according to the pressure value detected by the second pressure sensor.

[0029] The crossbeam is slidably connected to the tensioning pedestal, and the steel bars at any end of the reinforced concrete structure pass through the corresponding first steel bar through-holes and second steel bar through-holes in sequence, and are detachably fixedly connected to the crossbeam through anchor clips.

[0030] Another technical solution adopted by the embodiment of the present invention is: a method for removing steel bars from a reinforced concrete structure, comprising the following steps:

[0031] Step S1, fixing both ends of the reinforced concrete structure, and processing both ends of the reinforced concrete structure so that a certain length of steel bars are exposed at both ends;

[0032] Step S2, applying a cyclic load to the reinforced concrete structure, and then subjecting the steel bars to a hot and cold cycle treatment of a preset number of times, a preset duration, and a preset temperature, so as to destroy the bite effect of the contact surface between the concrete and the steel bars;

[0033] Step S3, alternately applying tension force to the exposed steel bars at both ends of the reinforced concrete structure to pull the steel bars;

[0034] Step S4, collecting the applied tensile force in real time, and the computer automatically draws a curve of the relationship between the pulling force, i.e. the applied tensile force and time;

[0035] Step S5, determine whether the pull-out force peak value in the tensioning force versus time curve exceeds the pull-out force range that can be achieved by manpower or the tensioning device. If so, return to step S2, increase the loading force and loading time of the cyclic load, and increase the preset number, preset duration, and preset temperature of the hot and cold cycle treatment, and perform hot and cold cycle treatment on the reinforced concrete structure after loading the cyclic load until the pull-out force peak value in the tensioning force versus time curve appears in the pull-out force range that can be achieved by manpower or the tensioning device, and then pull the steel bars out of the reinforced concrete structure by the current pull-out force.

[0036] Furthermore, in step S4, when increasing the loading force and loading time of the cyclic load, and increasing the preset number, preset duration and preset temperature of the hot and cold cycle treatment, the loading process of the cyclic load and the hot and cold cycle treatment process can be graded according to the loading effect and the hot and cold cycle treatment effect. The higher the grade, the better the loading effect and the hot and cold cycle treatment effect, that is, the better the destructive effect on the bite between the steel bar and the concrete. When cyclic steps S2 to S5, the loading process of the cyclic load and the hot and cold cycle treatment process are increased by one level each time a cycle is performed.

[0037] Furthermore, in step S1, the two ends of the reinforced concrete structure are cut by a cutting machine in regions and blocks, so that a certain length of steel bars are exposed at the ends of the two ends;

[0038] When the steel bars are cooled in step S2, the reinforced concrete structure is firstly wrapped with an insulation sleeve, and then cold air is filled into the insulation sleeve and maintained for a set cooling time to cool the reinforced concrete structure, thereby indirectly cooling the steel bars;

[0039] In step S3, when the tensioning force is alternately applied to the exposed steel bars at both ends of the reinforced concrete structure, the steel bars at any end of the reinforced concrete structure are first fixedly connected to the corresponding beam in the tensioning device, and then the corresponding jack is used to extend the beam to apply the tensioning force, and then the connection between the steel bars at this end and the corresponding beam in the tensioning device is removed, and then the steel bars at the other end of the reinforced concrete structure are fixedly connected to another corresponding beam in the tensioning device, and then the corresponding jack is used to extend the beam to apply the tensioning force, completing one alternation.

[0040] The beneficial effects of the embodiments of the present invention are as follows: a method is proposed, in which a cyclic load loading device is used to load a cyclic load on a reinforced concrete beam, at which time the reinforced concrete beam is subjected to bending moment and shear force, and under the action of bending moment and shear force, the bite between the steel bar and the concrete is damaged to a certain extent; then a hot and cold cycle device is used to perform hot and cold cycle treatment on the reinforced concrete beam, and under the action of alternating hot and cold, the bite between the steel bar and the concrete is further damaged; then, tensile force is alternately applied to the exposed steel bars at both ends of the reinforced concrete beam to pull the steel bars, the magnitude of the applied tensile force is collected in real time, and a computer automatically draws a curve chart of the relationship between the pull-out force and time, and according to the relationship between the pull-out force and time Whether the peak value of the pull-out force in the curve graph is within the pull-out force range that can be achieved by manpower or the tensioning device can be used to judge whether the damage to the bite of the steel bar and the concrete is sufficient. If it is sufficient, the steel bar can be directly pulled out, and the complete steel bar can be recovered, which reduces the breakage rate of the steel bar, effectively recycles the steel bar, and increases the utilization of the steel bar. The construction noise is small, and the smoke and dust generated is also small. It effectively solves the existing problem of recovering steel bars from reinforced concrete structures by violent crushing and cutting concrete, which will generate huge noise and a large amount of smoke and dust, and the steel bar breakage rate is large. It can be constructed at night, is friendly to the construction period requirements, and is equipped with a corresponding steel bar detachment device in the reinforced concrete structure, which is highly practical. BRIEF DESCRIPTION OF THE DRAWINGS

[0041] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0042] Figure 1 The present invention is a flowchart of a method for removing steel bars from a reinforced concrete structure according to an embodiment of the present invention.

[0043] Figure 2 It is a schematic structural diagram of a periodic load loading device and a hot and cold cycle device according to an embodiment of the present invention.

[0044] Figure 3 It is a schematic structural diagram of a fixing base according to an embodiment of the present invention.

[0045] Figure 4 It is a schematic diagram of the front view of the structure of the tensioning device according to an embodiment of the present invention.

[0046] Figure 5 It is a schematic top view of the structure of the tensioning device according to an embodiment of the present invention.

[0047] Figure 6 It is a schematic structural side view of a tensioning device according to an embodiment of the present invention.

[0048] In the figure, 1. fixed seat, 1-1. base, 1-2. pressure plate, 1-3. bolt, 2. loading beam, 3. periodic load controller, 4. pressure column, 5. threaded column, 6. electric heater, 7. electric heating controller, 8. tensioning base, 9. reinforced concrete pier, 10. cross beam, 11. jack, 12. anchor clip, 13. protective net, 14. tensioning controller. DETAILED DESCRIPTION

[0049] The following will be combined with the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0050] Example 1

[0051] This embodiment provides a device for removing steel bars from a reinforced concrete structure. The reinforced concrete structure in this embodiment is exemplified by a reinforced concrete beam, such as Figure 2~3 As shown, including:

[0052] The periodic load loading device and the hot and cold cycle device are arranged on the reinforced concrete structure. The periodic load loading device is used to load the periodic load on the reinforced concrete structure. The hot and cold cycle device is used to perform hot and cold cycle treatment on the reinforced concrete structure to destroy the bite between the steel bars and the concrete in the reinforced concrete structure.

[0053] The tensioning device is installed at both ends of the steel bars in the reinforced concrete structure and is used to pull the steel bars.

[0054] The periodic load loading device, such as Figure 2 As shown, including:

[0055] Fixed seat 1, both ends of the reinforced concrete beam are fixed on the corresponding fixed seats 1 respectively;

[0056] A loading beam 2, the loading beam 2 is arranged above the reinforced concrete beam, and a compression column 4 is arranged at the bottom of the loading beam 2 and is located just above the reinforced concrete beam;

[0057] The periodic load controller 3 is used to control the movement of the loading beam 2 to control the periodic load process of the pressure column 4.

[0058] In some embodiments, Figure 3As shown, the fixing seat 1 includes a base 1-1 and a pressure plate 1-2, and mounting holes are provided on the base 1-1 and the pressure plate 1-2. The end of the reinforced concrete beam is placed on the base 1-1 to ensure that the reinforced concrete is more stable even under the action of the loading load. The pressure plate 1-2 is placed on the top of the reinforced concrete beam. The base 1-1 and the pressure plate 1-2 are detachably connected by bolts 1-3 that pass through the mounting holes thereon and are located on the side of the reinforced concrete beam.

[0059] In some embodiments, a vertical threaded column 5 is provided on the top of the pressure plate 1-2 of each fixed seat 1, and the bottom of the threaded column 5 is rotatably connected to the pressure plate 1-2, and the two ends of the loading beam 2 are respectively threadedly connected to the corresponding threaded columns 5, and the two threaded columns 5 rotate synchronously to drive the loading beam 2 and the pressure column 4 to move up and down; the periodic load controller 3 is electrically connected to the servo system of the two threaded columns 5, and controls the rotation process of the two threaded columns 5 by controlling the working process of the servo system of the two threaded columns 5, thereby controlling the periodic load loading process of the loading beam 2 and the pressure column 4, including the start, end, loading speed and loading time.

[0060] In some embodiments, a first pressure sensor is installed at the bottom of the pressure column 4. The first pressure sensor is used to detect the axial force applied by the loading beam 2 and the pressure column 4 and feed back to the periodic load controller 3. The periodic load controller 3 controls the moving speed of the loading beam 2, that is, the loading speed, in a closed-loop manner according to the axial force detected by the first pressure sensor.

[0061] The hot and cold cycle device comprises:

[0062] An electric heater 6 is arranged on the exposed steel bars at both ends of the reinforced concrete beam to heat the steel bars;

[0063] An electric heating controller 7, which is electrically connected to the electric heater 6 and is used to control the heating process of the electric heater 6;

[0064] The insulation sleeve is installed on the reinforced concrete beam. The reinforced concrete beam is quickly cooled by filling it with flowing cooling medium, thereby indirectly cooling the steel bars in the reinforced concrete beam.

[0065] like Figures 4 and 5 As shown, the tensioning device comprises:

[0066] A tensioning pedestal 8, on which the reinforced concrete beam is horizontally placed;

[0067] Reinforced concrete piers 9, two reinforced concrete piers 9 are relatively arranged on the tensioning pedestal 8 at a certain distance, the distance between the reinforced concrete piers 9 is greater than the length of the reinforced concrete beam, and the two reinforced concrete piers 9 are both provided with first steel bar through-holes, and the reinforced concrete volume of the reinforced concrete piers 9 needs to be able to withstand the pressure of the jack 11 and the reinforced concrete beam when the steel bars are tensioned. Therefore, the reinforced concrete piers 9 and the tensioning pedestal 8 are formed as one piece as possible to improve the ability of the reinforced concrete piers 9 to resist pressure;

[0068] The cross beam 10, each cross beam 10 is arranged on the outer side of the corresponding reinforced concrete pier 9, and a second steel bar through hole is arranged thereon, and the steel bars at any end of the reinforced concrete beam are sequentially passed through the corresponding first steel bar through hole and the second steel bar through hole, and then are detachably fixedly connected with the cross beam 10 through a steel bar fixing structure;

[0069] Jacks 11, each jack 11 is horizontally fixed on the corresponding reinforced concrete pier 9, and its loading end is fixedly connected to the crossbeam 10;

[0070] The tensioning controller 14 is used to control the extension process of the jack 11 to achieve control of the tensioning force.

[0071] In some embodiments, a second pressure sensor is provided at the extension end of the jack 11, and the second pressure sensor feeds back the detected pressure value to the tensioning controller 14 in real time. The tensioning controller 14 is electrically connected to the jack 11, and controls the extension speed, i.e., the tensioning speed, of the jack 11 in a closed loop according to the pressure value detected by the second pressure sensor.

[0072] In some embodiments, a protective net 13 is installed on the top of the reinforced concrete pier 9 to prevent the steel bars from being suddenly broken and ejected from the end to injure workers.

[0073] In some embodiments, the cross beam 10 is slidably connected to the tensioning pedestal 8, and the steel bars at either end of the reinforced concrete beam are sequentially passed through the corresponding first steel bar perforations and second steel bar perforations, and then detachably fixedly connected to the cross beam 10 through the anchor clip 12, such as Figure 6 As shown, after the steel bars at one end are tensioned, the anchor clip 12 for fixing the steel bars is removed, the reinforced concrete beam is moved to the reinforced concrete pier 9 at the other end of the tensioning pedestal 8, and the steel bars at the right end are fixed and tensioned by the same method.

[0074] In some embodiments, the periodic load controller 3, the electric heating controller 7, and the tensioning controller 14 are all implemented by computers.

[0075] Example 2

[0076] This embodiment provides a method for removing steel bars from a reinforced concrete structure. Figure 1As shown, the following steps are included, and the reinforced concrete structure in this embodiment is exemplified as a reinforced concrete beam:

[0077] Step S1, fixing both ends of the reinforced concrete beam, and processing both ends of the reinforced concrete beam so that a certain length of steel bars are exposed at both ends;

[0078] Step S2, applying a cyclic load to the reinforced concrete beam, and then subjecting the steel bars to a hot and cold cycle treatment of a preset number of times, a preset duration, and a preset temperature, so as to destroy the bite effect of the contact surface between the concrete and the steel bars;

[0079] Step S3, applying tensioning force alternately to the exposed steel bars at both ends of the reinforced concrete beam to pull the steel bars, and when the steel bars are alternately stretched, the steel bars at the other end that are not tensioned are not subject to any fixed constraints;

[0080] Step S4, collecting the applied tensile force in real time, and the computer automatically draws a curve of the relationship between the pulling force, i.e. the applied tensile force and time;

[0081] Step S5, determine whether the pull-out force peak value in the tensioning force versus time curve exceeds the pull-out force range that can be achieved by manpower or the tensioning device. If so, return to step S2, increase the loading force and loading time of the cyclic load, and increase the preset number, preset duration, and preset temperature of the hot and cold cycle treatment, and perform hot and cold cycle treatment on the reinforced concrete beam after loading the cyclic load until the pull-out force peak value in the tensioning force versus time curve appears in the pull-out force range that can be achieved by manpower or the tensioning device, and then pull the steel bars out of the reinforced concrete beam by the current pull-out force.

[0082] In some embodiments, in step S1, the two ends of the reinforced concrete beam are respectively fixed on the fixing seat 1, and the two ends of the reinforced concrete beam are cut in regions and blocks by a cutting machine so that a certain length of steel bars are exposed at the ends of the two ends.

[0083] In some real-time examples, step S2 uses a periodic load loading device to load a periodic load on a reinforced concrete beam. At this time, the reinforced concrete beam is subjected to bending moment and shear force. Under the action of bending moment and shear force, the bite of the steel bar and concrete is damaged to a certain extent; then a hot and cold cycle device is used to perform hot and cold cycle treatment on the steel bar. Specifically, the electric heater 6 is first used to heat the steel bar, and then the insulation sleeve is used to wrap the reinforced concrete beam, and cold air is filled into the insulation sleeve and maintained for a set cooling time to cool the reinforced concrete beam, thereby indirectly cooling the steel bar. Under the alternating action of hot and cold, the bite of the steel bar and concrete is further damaged.

[0084] In some real-time examples, in step S3, a tensioning device is used to alternately apply tensioning force to the exposed steel bars at both ends of the reinforced concrete beam to pull the steel bars. When the tensioning force is alternately applied to the exposed steel bars at both ends of the reinforced concrete beam, the steel bars at any end of the reinforced concrete beam are first fixedly connected to the corresponding crossbeam 10 in the tensioning device, and then the crossbeam 10 is stretched by the corresponding jack 11 to apply tensioning force, and then the connection between the steel bars at this end and the corresponding crossbeam 10 in the tensioning device is removed, and then the steel bars at the other end of the reinforced concrete beam are fixedly connected to another corresponding crossbeam 10 in the tensioning device, and then the crossbeam 10 is stretched by the corresponding other jack 11 to apply tensioning force, and one alternation is completed.

[0085] In some embodiments, in step S4, when increasing the loading force and loading time of the cyclic load, and increasing the preset number, preset duration, and preset temperature of the hot and cold cycle treatment, the loading process of the cyclic load and the hot and cold cycle treatment process can be divided into levels according to the loading effect and the hot and cold cycle treatment effect. The higher the level, the better the loading effect and the hot and cold cycle treatment effect, that is, the better the destructive effect on the bite between the steel bar and the concrete. When cyclic steps S2~S5, the loading process of the cyclic load and the hot and cold cycle treatment process are increased by one level each time a cycle is performed.

[0086] The above description is only a preferred embodiment of the present invention and is not intended to limit the protection scope of the present invention. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present invention are included in the protection scope of the present invention.

Claims

1. A device for removing steel bars from a reinforced concrete structure, characterized in that: include: The periodic load loading device and the hot and cold cycle device are arranged on the reinforced concrete structure. The periodic load loading device is used to load the periodic load on the reinforced concrete structure. The hot and cold cycle device is used to perform hot and cold cycle treatment on the reinforced concrete structure to destroy the bite between the steel bars and the concrete in the reinforced concrete structure. A tensioning device is provided at both ends of the steel bars in the reinforced concrete structure and is used to pull the steel bars; The periodic load loading device comprises: A fixing seat (1), with both ends of the reinforced concrete structure being fixed to corresponding fixing seats (1) respectively; A loading beam (2), the loading beam (2) being arranged above the reinforced concrete structure, and a compression column (4) located above the reinforced concrete structure being arranged at the bottom of the loading beam (2); A periodic load controller (3), the periodic load controller (3) is used to control the movement of the loading beam (2) to control the periodic load process of the pressure column (4); The fixing seat (1) comprises a base (1-1) and a pressing plate (1-2), the base (1-1) and the pressing plate (1-2) being provided with mounting holes, the end of the reinforced concrete structure being placed on the base (1-1), the pressing plate (1-2) being placed on the reinforced concrete structure, and the base (1-1) and the pressing plate (1-2) being detachably connected via bolts (1-3) passing through the mounting holes thereon and located on the side of the reinforced concrete structure; A vertical threaded column (5) is provided on the top of the pressure plate (1-2) of each fixed seat (1), the bottom of the threaded column (5) is rotatably connected to the pressure plate (1-2), and both ends of the loading beam (2) are respectively threadedly connected to the corresponding threaded columns (5), and the two threaded columns (5) rotate synchronously to drive the loading beam (2) and the pressure column (4) to move up and down; The periodic load controller (3) is electrically connected to the servo system of the two threaded columns (5), and controls the rotation process of the two threaded columns (5) by controlling the working process of the servo system of the two threaded columns (5), thereby controlling the periodic load loading process of the loading beam (2) and the pressure column (4); A first pressure sensor is installed at the bottom of the pressure column (4). The first pressure sensor is used to detect the axial force applied by the loading beam (2) and the pressure column (4) and to feed back to the periodic load controller (3). The periodic load controller (3) controls the movement speed of the loading beam (2), i.e., the loading speed, in a closed loop according to the axial force detected by the first pressure sensor.

2. A device for removing steel bars from a reinforced concrete structure according to claim 1, characterized in that: The hot and cold cycle device comprises: An electric heater (6), the electric heater (6) being arranged on the steel bars exposed at both ends of the reinforced concrete structure, and being used to heat the steel bars; An electric heating controller (7), the electric heating controller (7) being electrically connected to the electric heater (6) and being used to control a heating process of the electric heater (6); The insulation sleeve is installed on the reinforced concrete structure. The reinforced concrete structure is quickly cooled by filling it with flowing cooling medium, thereby indirectly cooling the steel bars in the reinforced concrete structure.

3. A device for removing steel bars from a reinforced concrete structure according to claim 1 or 2, characterized in that: The tensioning device comprises: A tensioning pedestal (8), on which the reinforced concrete structure is horizontally placed; Reinforced concrete piers (9), wherein two reinforced concrete piers (9) are arranged on the tensioning pedestal (8) at a certain distance from each other, the distance between the reinforced concrete piers (9) is greater than the length of the reinforced concrete structure, and first steel bar through holes are provided on both reinforced concrete piers (9); A crossbeam (10), each crossbeam (10) is arranged on the outside of a corresponding reinforced concrete pier (9), and is provided with a second steel bar through-hole, and the steel bars at any end of the reinforced concrete structure are sequentially passed through the corresponding first steel bar through-hole and second steel bar through-hole, and then are detachably fixedly connected to the crossbeam (10) through a steel bar fixing structure; Jacks (11), each jack (11) is horizontally fixed on a corresponding reinforced concrete pier (9), and a loading end thereof is fixedly connected to a crossbeam (10); A tensioning controller (14) is used to control the extension process of the jack (11) to achieve control of the tensioning force.

4. A device for removing steel bars from a reinforced concrete structure according to claim 3, characterized in that: A second pressure sensor is provided at the extension end of the jack (11), and the second pressure sensor feeds back the detected pressure value to the tensioning controller (14) in real time. The tensioning controller (14) is electrically connected to the jack (11), and controls the extension speed of the jack (11) in a closed loop according to the pressure value detected by the second pressure sensor. The crossbeam (10) is slidably connected to the tensioning pedestal (8), and the steel bars at any end of the reinforced concrete structure are sequentially passed through the corresponding first steel bar through-holes and second steel bar through-holes, and then detachably fixedly connected to the crossbeam (10) through anchor clips (12).

5. A method for removing steel bars from a reinforced concrete structure, characterized in that: The following steps are involved: Step S1, fixing both ends of the reinforced concrete structure, and processing both ends of the reinforced concrete structure so that a certain length of steel bars are exposed at both ends; Step S2, applying a cyclic load to the reinforced concrete structure, and then subjecting the steel bars to a hot and cold cycle treatment of a preset number of times, a preset duration, and a preset temperature, so as to destroy the bite effect of the contact surface between the concrete and the steel bars; Step S3, alternately applying tension force to the exposed steel bars at both ends of the reinforced concrete structure to pull the steel bars; Step S4, collecting the applied tensile force in real time, and the computer automatically draws a curve of the relationship between the pulling force, i.e. the applied tensile force and time; Step S5, determine whether the pull-out force peak value in the tensioning force versus time curve exceeds the pull-out force range that can be achieved by manpower or the tensioning device. If so, return to step S2, increase the loading force and loading time of the cyclic load, and increase the preset number, preset duration, and preset temperature of the hot and cold cycle treatment, and perform hot and cold cycle treatment on the reinforced concrete structure after loading the cyclic load until the pull-out force peak value in the tensioning force versus time curve appears in the pull-out force range that can be achieved by manpower or the tensioning device, and then pull the steel bars out of the reinforced concrete structure by the current pull-out force.

6. A method for removing steel bars from a reinforced concrete structure according to claim 5, characterized in that: In step S4, when the loading force and loading time of the cyclic load are increased, and the preset number, preset duration and preset temperature of the hot and cold cycle treatment are increased, the loading process of the cyclic load and the hot and cold cycle treatment process can be divided into levels according to the loading effect and the hot and cold cycle treatment effect. The higher the level, the better the loading effect and the hot and cold cycle treatment effect, that is, the better the destructive effect on the bite between the steel bar and the concrete. When the steps S2 to S5 are cyclically performed, the loading process of the cyclic load and the hot and cold cycle treatment process are increased by one level each time a cycle is performed.

7. A method for removing steel bars from a reinforced concrete structure according to claim 5, characterized in that: In step S1, the two ends of the reinforced concrete structure are cut by a cutting machine in sections and blocks, so that a certain length of steel bars are exposed at the ends of the two ends; When the steel bars are cooled in step S2, the reinforced concrete structure is firstly wrapped with an insulation sleeve, and then cold air is filled into the insulation sleeve and maintained for a set cooling time to cool the reinforced concrete structure, thereby indirectly cooling the steel bars; In step S3, when the tensioning force is alternately applied to the exposed steel bars at both ends of the reinforced concrete structure, the steel bars at any end of the reinforced concrete structure are first fixedly connected to the corresponding crossbeam (10) in the tensioning device, and then the crossbeam (10) is extended by the corresponding jack (11) to apply the tensioning force, and then the connection between the steel bars at this end and the corresponding crossbeam (10) in the tensioning device is removed, and then the steel bars at the other end of the reinforced concrete structure are fixedly connected to another corresponding crossbeam (10) in the tensioning device, and then the crossbeam (10) is extended by the corresponding other jack (11) to apply the tensioning force, completing one alternation.

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