Bending device and method for reducing prestress loss of broken line pre-tensioning method precast beam

Abstract

The invention relates to the technical field of prefabricated beam manufacturing, and particularly discloses a bending device and method for reducing the prestress loss of a broken line pre-tensioning method prefabricated beam, the bending device comprises a pedestal assembly, a clamping assembly is placed on the upper surface of the pedestal assembly, a bending assembly is fixedly installed on the upper surface of the clamping assembly, and a pre-tightening force rib is arranged in an inner cavity of the bending assembly; whether the table top is horizontal or not can be detected through the table base assembly, the levelness of the table top can be adjusted when the table top is inclined, so that the bending device keeps horizontal when bending the prestressed tendons, the bending device can be kept at a fixed position through the clamping assembly, the prestressed tendons are prevented from deviating from a preset track in the bending process, and the bending quality of the prestressed tendons is improved. According to the prestressed tendon bending device, the height of the bent prestressed tendons can be adjusted through the bending assembly, the prestressed tendons of various specifications can be bent, in addition, the bending assembly can be conveniently disassembled, meanwhile, an alarm can be given out when disassembly is not planned, and the maintenance efficiency of workers is improved.

Description

Technical Field

[0001] The present application relates to the technical field of prefabricated beam manufacturing, and in particular to a bending device and method for reducing the prestress loss of a prefabricated beam using a fold line pretensioning method. Background Art

[0002] In the field of bridge engineering, prestressed concrete beams are widely used due to their excellent structural performance and economic benefits. Among them, the zigzag prestressed concrete beam, as an innovative beam type, has gradually received attention in recent years. By adopting the zigzag reinforcement method, the zigzag prestressed beam can not only effectively reduce the principal tensile stress at the beam end and improve the structural performance, but also increase the span of the structure to meet the needs of modern bridge engineering for large spans and high durability. However, in the construction process of the zigzag prestressed concrete beam, the loss of prestress is an urgent problem to be solved. The loss of prestress is mainly caused by the bending device. These losses will not only affect the bearing capacity of the beam body, but also increase the construction difficulty and cost, and reduce the economic benefits of the project.

[0003] The existing technology still has the following problems:

[0004] 1. The existing bending devices are all placed on a table, and then the prestressed tendons are bent. In the prior art, the table is placed on a horizontal ground, while the ground of the construction site is mostly uneven, which causes the bending device to tilt, making it difficult to ensure that the prestressed tendons are in the correct position during the tensioning process, and the prestressed tendons may deviate from the designed position, resulting in uneven prestress distribution, thereby affecting the overall force performance and durability of the beam body. The uneven table may also cause the prestressed tendons to apply eccentric loads to the components, which will aggravate the stress concentration phenomenon of the components and increase the risk of cracking.

[0005] 2. When the bending device bends the prestressed tendon, the position of the bending device needs to be kept relatively fixed. In the prior art, the position of the bending device is easily offset during bending. The offset will cause the prestressed tendon to deviate from the predetermined trajectory during the bending process, resulting in the geometric shape after bending not meeting the design requirements.

[0006] 3. The existing bending devices are all fixed structures and cannot adjust the height of the prestressed tendons to be bent. When the design of the prefabricated beam changes, the height-unadjustable bender may not be able to meet the new requirements, resulting in increased construction difficulty. At the same time, the bending device needs to be replaced when bending prestressed tendons of different specifications. In addition, the bending assembly needs to be dismantled after bending the prestressed tendons. The existing bending devices are inconvenient to disassemble and difficult to reuse. Summary of the invention

[0007] The present application provides a bending device and method for reducing the loss of prestress in precast beams using the fold line pretensioning method, thereby solving the problems in the prior art that the bending device is tilted, the position of the bending device is easily offset during bending, and the bending assembly is inconvenient to disassemble and reuse. The application achieves the goal of keeping the bending device horizontal when bending the prestressed tendons, keeping the bending device in a fixed position, and facilitating the disassembly of the bending assembly.

[0008] The present application provides a bending device for reducing the prestress loss of prefabricated beams using a fold line pretensioning method, comprising a pedestal assembly, a clamping assembly placed on the upper surface of the pedestal assembly, a bending assembly fixedly mounted on the upper surface of the clamping assembly, an inner cavity of the bending assembly provided with pre-tightening tendons, the bending assembly comprising a second connecting plate, a fixing frame fixedly mounted on the upper surface of the second connecting plate, a second connecting frame provided on one side of the fixing frame, a bending mechanism slidably connected to the inner cavity of the fixing frame, an adjusting mechanism provided at the upper end of the fixing frame, a disassembly and assembly mechanism provided at the lower end of the fixing frame, and an alarm mechanism provided above the disassembly and assembly mechanism.

[0009] Furthermore, the bending mechanism includes a bending frame, the inner cavity of the bending frame is rotatably connected to a fourth threaded rod, the outer surface of the bending frame is provided with a bending rod, one bending frame has three bending rods, and the bending rod in the middle is fixedly connected to the bending frame, the bending rods at both ends are slidably connected to the bending frame, the fourth threaded rod is sleeved with the bending rod, and the bending rods at both ends are connected to the bending frame by threads, the threads at both ends of the fourth threaded rod are in opposite directions, the bending frame is slidably connected to the fixed frame and the second connecting frame, and the bending rod is slidably connected to the fixed frame.

[0010] Furthermore, the adjusting mechanism includes a second connecting block, the second connecting block and the upper end of the bending frame are fixedly connected, the inner cavity of the second connecting block is slidably connected with a second plug rod, the outer surface of the second plug rod is sleeved with a first spring, the outer surface of the second plug rod is fixedly installed with a fixing ring, the fixing ring is located in the inner cavity of the second connecting block, the outer surface of the fixing frame is fixedly installed with a fixing strip, the outer surface of the fixing strip is provided with a second limiting hole, the second plug rod and the second limiting hole are inserted into each other, the first spring is located between the fixing ring and the inner wall of the second connecting block, and the second connecting block and the fixing frame are slidably connected.

[0011] Furthermore, the disassembly and assembly mechanism includes a fixing rod, which is fixedly connected to the bottom end of the second connecting frame, a card slot is opened at one end of the fixing rod away from the second connecting frame, a second fixing block is fixedly installed on the outer surface of the fixing frame, an elastic rod is slidably connected to the inner cavity of the second fixing block, a card block is fixedly installed on the bottom end of the elastic rod, a second spring is sleeved on the outer surface of the elastic rod, the second spring is located between the second fixing block and the card block, and the card block and the card slot are inserted into each other.

[0012] Furthermore, the alarm mechanism includes a slider, which is slidably connected to a fixed frame, a button is provided on the lower surface of the slider, an alarm is fixedly installed on the upper surface of the slider, the button and the alarm are electrically connected, a third fixed block is fixedly installed on the outer surface of the fixed frame, a third spring is fixedly connected to the outer surface of the third fixed block, the button is directly above the elastic rod, one end of the third spring away from the third fixed block is in contact with the slider, and pressing the button controls the alarm to sound an alarm.

[0013] Furthermore, the pedestal assembly includes a support platform, support legs are fixedly installed at the four corners of the support platform, a balance checking mechanism is arranged in the middle part of the support platform, a lifting mechanism is arranged on the lower surface of the support platform, and first limit holes are opened on both sides of the support platform.

[0014] Furthermore, the balance inspection mechanism includes a detection disk, a slide groove is provided on the lower surface of the detection disk, a slide is slidably connected to the inner cavity of the slide groove, a detection frame is fixedly installed in the middle part of the slide, a moving block is slidably connected to the inner cavity of the detection frame, a gravity block is fixedly installed at the bottom middle position of the moving block, a pointer is fixedly installed on the outer surface of the moving block, rollers are rotatably connected to both ends of the moving block, the rollers and the inner cavity of the detection frame are rotatably connected, a first threaded rod is rotatably connected to the inner cavity of the bottom end of the detection frame, the first threaded rod and the slide are rotatably connected, detection blocks are sleeved on both ends of the first threaded rod, the detection block and the first threaded rod are threadedly connected, and the threads at both ends of the first threaded rod are in opposite directions, a detection rod is fixedly installed on the outer surface of the detection block close to the middle side of the detection frame, the detection rod and the two ends of the moving block are in contact, and the pointer points to the middle part of the detection frame when the detection disk is horizontal.

[0015] Furthermore, the lifting mechanism includes a support plate, a first fixed block is fixedly installed on the upper surface of the support plate, two first fixed blocks are on one support plate, the first fixed blocks are symmetrically distributed on the support plate, the inner cavity of the first fixed block is slidably connected with the lifting block, the inner cavity of the first fixed block is sleeved with a second threaded rod, the second threaded rod and the first fixed block are threadedly connected, the threads at both ends of the second threaded rod are in opposite directions, the two ends of the lifting block are rotatably connected with the first connecting strip, the middle part of the first connecting strip is rotatably connected with the second connecting strip, the end of the second connecting strip away from the first connecting strip is rotatably connected to the support plate, the end of the first connecting strip away from the lifting block is rotatably connected to the first connecting block, the upper surface of the first connecting block is fixedly installed with the first connecting plate, the first connecting plate is fixedly connected to the support platform, and the support plate and the lower surface of the support leg are flush.

[0016] Furthermore, the clamping assembly includes a clamping frame, the inner cavity of the clamping frame is rotatably connected to a third threaded rod, the inner cavity of the clamping frame is slidably connected to an adjusting block, a clamping block is fixedly installed on the end of the adjusting block away from the clamping frame, a first insertion rod is fixedly installed on the outer surface of the clamping block, the first insertion rod is inserted into the first limiting hole, a first connecting frame is fixedly installed on the upper surface of the clamping frame, the first connecting frame is fixedly connected to the second connecting plate, the adjusting block and the third threaded rod are threadedly connected, and the thread directions at both ends of the third threaded rod are opposite.

[0017] A method for reducing the prestress loss of a precast beam using a fold line pretensioning method, performed by the above device, comprises the following steps:

[0018] S1. Optimize the bending device, and adjust the pedestal assembly to keep the bending assembly horizontal when bending the prestressing tendons, so as to ensure that the prestressing tendons are in the correct position during the tensioning process and the prestressing tendons are evenly distributed;

[0019] S2. Fix the position of the bending component by means of a clamping component to prevent the position of the bending component from shifting during bending, so that the preloaded reinforcement maintains a predetermined trajectory during the bending process, and the geometric shape after bending meets the design requirements;

[0020] S3. The bending assembly can be quickly installed and disassembled, which is convenient for reuse after the prestressing bars are bent. The bending height of the bending assembly can be adjusted, and different types of prestressing bars can be bent to improve the fault tolerance of the bending assembly. The optimized structure can reduce the prestress loss of the precast beam using the fold line pre-tensioning method.

[0021] The technical solution provided by this application has at least the following technical effects or advantages:

[0022] 1. The use of a pedestal assembly effectively solves the problem that the existing bending devices are all placed on a table and then the prestressed tendons are bent. In the prior art, the table is placed on a horizontal ground, while the ground of the construction site is mostly uneven, which causes the bending device to tilt, making it difficult to ensure that the prestressed tendons are in the correct position during the tensioning process, and the prestressed tendons may deviate from the designed position, resulting in uneven distribution of prestress, thereby affecting the overall force-bearing performance and durability of the beam body. The uneven table surface may also cause the prestressed tendons to apply eccentric loads to the components, and the eccentric loads will aggravate the stress concentration phenomenon of the components and increase the risk of cracking. The present invention can detect whether the table is horizontal through the pedestal assembly, and can adjust the horizontality of the table when the table is tilted, so that the bending device keeps the prestressed tendons horizontal when bending, ensuring that the prestressed tendons are in the correct position during the tensioning process, avoiding the prestressed tendons from deviating from the designed position, ensuring uniform distribution of prestress, thereby improving the overall force-bearing performance and durability of the beam body, avoiding the prestressed tendons from applying eccentric loads to the components, and reducing the risk of cracking of the prefabricated beam.

[0023] 2. The use of the clamping assembly effectively solves the problem of keeping the bending device in a relatively fixed position when the bending device bends the prestressed tendon. In the prior art, the position of the bending device is easily offset during bending, and the offset will cause the prestressed tendon to deviate from the predetermined trajectory during the bending process, resulting in the geometric shape after bending not meeting the design requirements. The present invention can keep the bending device in a fixed position through the clamping assembly, preventing the prestressed tendon from deviating from the predetermined trajectory during the bending process, so that the geometric shape after bending meets the design requirements.

[0024] 3. The use of the bending assembly effectively solves the problem that the existing bending devices are all fixed structures and cannot adjust the height of the prestressed tendons that need to be bent. When the design of the prefabricated beam changes, the height-unadjustable bender may not be able to meet the new requirements, resulting in increased construction difficulty. At the same time, the bending device needs to be replaced when bending prestressed tendons of different specifications. In addition, the bending assembly needs to be dismantled after bending the prestressed tendons. The existing bending assemblies are inconvenient to disassemble and difficult to reuse. The present invention can adjust the height of the bent prestressed tendons through the bending assembly, which is convenient for adjusting the bending height of the prestressed tendons according to needs when the design of the prefabricated beam changes, and can bend prestressed tendons of various specifications, thereby improving the fault tolerance of the equipment. In addition, the bending assembly is easy to dismantle for subsequent reuse. At the same time, an alarm can be issued during unplanned dismantling to improve the maintenance of staff. BRIEF DESCRIPTION OF THE DRAWINGS

[0025] Figure 1 This is a schematic diagram of the overall structure of Example 1 of the present application;

[0026] Figure 2 This is a schematic diagram of the supporting leg structure in Example 1 of the present application;

[0027] Figure 3 This is a schematic diagram of the structure of the balance check mechanism in the first embodiment of the present application;

[0028] Figure 4 This is a schematic diagram of the structure of the detection frame in Example 1 of the present application;

[0029] Figure 5 This is a schematic diagram of the lifting mechanism structure in Example 1 of the present application;

[0030] Figure 6 This is a schematic diagram of the structure of the clamping assembly in Example 1 of the present application;

[0031] Figure 7 This is a schematic diagram of the structure of the first connecting frame in Embodiment 1 of the present application;

[0032] Figure 8 This is a schematic diagram of the bending assembly structure in Example 1 of the present application;

[0033] Fig. 9 This is a schematic diagram of the structure of the second connecting frame in the first embodiment of the present application;

[0034] Fig.10 This is a schematic diagram of the structure of the second connecting plate in Embodiment 1 of the present application;

[0035] Fig.11 For Example 1 of this application Fig.10 A schematic diagram of the structure enlargement at the center A;

[0036] Fig.12 This is a schematic diagram of the bending mechanism structure in Example 1 of the present application;

[0037] Fig.13 This is a schematic diagram of the structure of the alarm mechanism in Example 1 of the present application.

[0038] In the figure: 1, pedestal assembly; 11, support table; 12, support leg; 13, balance check mechanism; 131, detection plate; 132, slide; 133, slide; 134, detection frame; 135, moving block; 136, gravity block; 137, pointer; 138, roller; 139, first threaded rod; 1310, detection block; 1311, detection rod; 14, lifting mechanism; 141, support plate; 142, first fixed block; 143, lifting block; 144, second threaded rod; 145, first connecting strip; 146, second connecting strip; 147, first connecting block; 148, first connecting plate; 15, first limiting hole; 2, clamping assembly; 21, clamping frame; 22, third threaded rod; 23, adjustment block; 24, clamping block; 25, The first plug rod; 26, the first connecting frame; 3, the bending assembly; 31, the second connecting plate; 32, the fixing frame; 33, the second connecting frame; 34, the bending mechanism; 341, the bending frame; 342, the fourth threaded rod; 343, the bending rod; 35, the adjusting mechanism; 351, the second connecting block; 352, the second plug rod; 353, the first spring; 354, the fixing ring; 355, the fixing strip; 356, the second limiting hole; 36, the disassembly and assembly mechanism; 361, the fixing rod; 362, the slot; 363, the second fixing block; 364, the elastic rod; 365, the block; 366, the second spring; 37, the alarm mechanism; 371, the slider; 372, the button; 373, the alarm; 374, the third fixing block; 375, the third spring; 4, the preload rib. DETAILED DESCRIPTION

[0039] The table tops are all placed on the horizontal ground, while the ground of the construction site is mostly uneven, which causes the bending device to tilt. The present invention can detect whether the table top is horizontal through the base assembly, and can adjust the horizontality of the table top when the table top is tilted, so that the bending device can remain horizontal when bending the prestressed tendons; the position of the bending device is easy to shift during bending, and the present invention can keep the bending device in a fixed position through the clamping assembly; the bending assembly is inconvenient to disassemble and difficult to reuse, and the present invention facilitates the disassembly of the bending assembly through the bending assembly, so as to facilitate subsequent reuse.

[0040] In order to better understand the above technical solution, the above technical solution will be described in detail below in conjunction with the accompanying drawings and specific implementation methods.

[0041] Example

[0042] See also Figure 1 As shown, a bending device for reducing the prestress loss of precast beams by fold line pretensioning method comprises a pedestal assembly 1, a clamping assembly 2 is placed on the upper surface of the pedestal assembly 1, a bending assembly 3 is fixedly installed on the upper surface of the clamping assembly 2, a preloaded tendon 4 is arranged in the inner cavity of the bending assembly 3, the pedestal assembly 1 is used to keep the bending assembly 3 horizontal, the clamping assembly 2 is used to keep the position of the bending assembly 3 fixed, the bending assembly 3 is used to bend the preloaded tendon 4, and the bending assembly 3 can be quickly disassembled and assembled, so that the preloaded tendon 4 can be removed after being bent, the bending assembly 3 can adjust the bending height of the preloaded tendon 4, and can bend bending assemblies 3 of different specifications, the bender is optimized, and the pedestal assembly 1 is adjusted to make the bending assembly 3 have a certain bending height when bending the preloaded tendon 4 When bending, the bending component 3 remains horizontal to ensure that the prestressing tendons 4 are in the correct position during the tensioning process, so that the prestress of the prestressing tendons 4 is evenly distributed. The position of the bending component 3 is fixed by the clamping component 2 to prevent the position of the bending component 3 from shifting during the bending process, so that the prestressing tendons 4 maintain a predetermined trajectory during the bending process, and the geometric shape after bending meets the design requirements. The bending component 3 can be quickly installed and disassembled, which is convenient for reuse after the prestressing tendons 4 are bent. The bending height of the bending component 3 can be adjusted, and prestressing tendons 4 of different models can be bent, thereby improving the fault tolerance of the bending component 3. The optimized structure can reduce the prestress loss of precast beams using the fold line pre-tensioning method.

[0043] See also Figure 2As shown, the pedestal assembly 1 includes a support platform 11, support legs 12 are fixedly installed at the four corners of the support platform 11, a balance check mechanism 13 is arranged in the middle part of the support platform 11, a lifting mechanism 14 is arranged on the lower surface of the support platform 11, and first limiting holes 15 are opened on both sides of the support platform 11. The support legs 12 are used to support the support platform 11, the balance check mechanism 13 is used to detect the horizontality of the support platform 11, the lifting mechanism 14 is used to adjust the horizontality of the support platform 11 to keep the support platform 11 horizontal, and the first limiting hole 15 is used to be inserted into the clamping assembly 2 to keep the bending assembly 3 fixed.

[0044] See also Figure 3 and Figure 4As shown, the balance inspection mechanism 13 includes a detection plate 131, a slide groove 132 is provided on the lower surface of the detection plate 131, a slide 133 is slidably connected to the inner cavity of the slide groove 132, a detection frame 134 is fixedly installed in the middle part of the slide 133, a moving block 135 is slidably connected to the inner cavity of the detection frame 134, a gravity block 136 is fixedly installed at the bottom middle position of the moving block 135, the gravity block 136 is convenient for driving the moving block 135 to move in the inner cavity of the detection frame 134, so that the moving block 135 is kept in the middle part of the detection frame 134 in a horizontal position, and the outer surface of the moving block 135 is fixedly installed. A pointer 137 is fixedly installed, and rollers 138 are rotatably connected at both ends of the moving block 135. The rollers 138 are rotatably connected to the inner cavity of the detection frame 134. The inner cavity at the bottom end of the detection frame 134 is rotatably connected to a first threaded rod 139. The first threaded rod 139 is rotatably connected to the slide 133. Both ends of the first threaded rod 139 are sleeved with detection blocks 1310. The detection block 1310 and the first threaded rod 139 are connected by threads, and the threads at both ends of the first threaded rod 139 are in opposite directions. A detection rod 1311 is fixedly installed on the outer surface of the detection block 1310 close to the middle side of the detection frame 134. The two ends of the measuring rod 1311 and the moving block 135 fit together, and the detecting rod 1311 is driven to move by rotating the first threaded rod 139, so as to facilitate observation of the distance between the moving blocks 135 and the detecting rod 1311 at both ends of the detecting frame 134. When the detecting plate 131 is horizontal, the pointer 137 points to the middle part of the detecting frame 134. When the supporting platform 11 tilts, the detecting plate 131 is driven to tilt, and the tilting of the detecting plate 131 drives the sliding frame 133 to tilt, and the tilting of the sliding frame 133 drives the detecting frame 134 to tilt, and the tilting of the detecting frame 134 drives the moving block 135 to move in the inner cavity of the detecting frame 134. At this time, the pointer 137 points to the middle part of the detecting frame 134. 137 is offset, and the distance between the detection rod 1311 and the moving block 135 is changed. The gap between the moving block 135 and the detection rod 1311 and the direction of the pointer 137 above the detection frame 134 are observed to determine in which direction the support platform 11 is tilted. The lifting mechanism 14 is adjusted to replace the support legs 12 for support to keep the support platform 11 horizontal. The slide 133 slides on the slide groove 132 to rotate the slide 133 as a whole relative to the support platform 11. At this time, it is possible to observe whether the support platform 11 is horizontal in all directions, and then the bending component 3 is kept relatively horizontal through adjustment.

[0045] See also Figure 5As shown, the lifting mechanism 14 includes a support plate 141, a first fixed block 142 is fixedly installed on the upper surface of the support plate 141, two first fixed blocks 142 are on one support plate 141, and the first fixed blocks 142 are symmetrically distributed on the support plate 141, the inner cavity of the first fixed block 142 is slidably connected with a lifting block 143, the inner cavity of the first fixed block 142 is sleeved with a second threaded rod 144, the second threaded rod 144 and the first fixed block 142 are threadedly connected, and the threads at both ends of the second threaded rod 144 are in opposite directions, the two ends of the lifting block 143 are rotatably connected with a first connecting bar 145, the middle part of the first connecting bar 145 is rotatably connected with a second connecting bar 146, the end of the second connecting bar 146 away from the first connecting bar 145 is rotatably connected to the support plate 141, the end of the first connecting bar 145 away from the lifting block 143 is rotatably connected to the first connecting block 147, the upper surface of the first connecting block 147 is fixedly installed with a first connecting plate 148, the first connecting plate 148 and the support platform 11 is fixedly connected, and the lower surfaces of the support plate 141 and the support leg 12 are flush. When the support platform 11 tilts, the second threaded rod 144 can be rotated to drive the lifting block 143 to slide in the inner cavity of the first fixed block 142, and the lifting block 143 moves to drive the first connecting bar 145 to rotate, and the rotation of the first connecting bar 145 drives the second connecting bar 146 to rotate, and the rotation of the second connecting bar 146 and the first connecting bar 145 drives the height of the first connecting block 147 to change, thereby changing the height of the first connecting plate 148. That is, when the support platform 11 tilts, the lifting mechanism 14 at the position where the support leg 12 cannot stably support is adjusted to make the support plate 141 contact with the ground, so that the bending component 3 on the support platform 11 remains horizontal, ensuring that the prestressing bar 4 is in the correct position during the tensioning process, so that the prestress is evenly distributed, thereby improving the overall force performance and durability of the beam body, avoiding the prestressing bar 4 from applying eccentric loads to the precast beam components, and reducing the risk of cracking of the precast beam.

[0046] See also Figure 2 , Figure 6 and Figure 7As shown, the clamping assembly 2 includes a clamping frame 21, the inner cavity of the clamping frame 21 is rotatably connected to the third threaded rod 22, the inner cavity of the clamping frame 21 is slidably connected to the adjusting block 23, the end of the adjusting block 23 away from the clamping frame 21 is fixedly installed with a clamping block 24, the outer surface of the clamping block 24 is fixedly installed with a first plug rod 25, the first plug rod 25 and the first limiting hole 15 are inserted, the upper surface of the clamping frame 21 is fixedly installed with a first connecting frame 26, the first connecting frame 26 and the second connecting plate 31 are fixedly connected, and the adjusting block 23 and the third threaded rod 22 are connected. Through threaded connection, the thread directions of the two ends of the third threaded rod 22 are opposite. By rotating the third threaded rod 22, the adjusting block 23 is driven to move in the inner cavity of the clamping frame 21, so that the clamping block 24 is expanded, and then the third threaded rod 22 is rotated again to shrink the clamping block 24, and the first insertion rod 25 and the first limiting hole 15 are inserted into each other, so that the bending assembly 3 on the first connecting frame 26 is fixed in the fixed position of the support platform 11. After bending, the clamping assembly 2 can also be quickly removed from the pedestal assembly 1, and the pedestal assembly 1 can be used as a bottom template during subsequent pouring.

[0047] See also Figure 1 and Figure 8 As shown, the bending assembly 3 includes a second connecting plate 31, which is used to be fixedly connected to the first connecting frame 26. A fixing frame 32 is fixedly installed on the upper surface of the second connecting plate 31, and a second connecting frame 33 is arranged on one side of the fixing frame 32. The inner cavity of the fixing frame 32 is slidably connected with a bending mechanism 34, and the bending mechanism 34 can be used to bend the preload rib 4. An adjusting mechanism 35 is arranged at the upper end of the fixing frame 32, and a disassembly mechanism 36 is arranged at the lower end of the fixing frame 32. An alarm mechanism 37 is arranged above the disassembly mechanism 36. The fixing frame 32 and the second connecting frame 33 are connected by the disassembly mechanism 36, which facilitates the removal of the second connecting frame 33 so that the bending mechanism 34 can be moved out on one side of the preload rib 4. The adjusting mechanism 35 is used to adjust the height of the bending mechanism 34, and the alarm mechanism 37 is used to sound an alarm when the second connecting frame 33 and the fixing frame 32 are separated unplanned.

[0048] See also Figure 8 and Fig.12As shown, the bending mechanism 34 includes a bending frame 341, the inner cavity of the bending frame 341 is rotatably connected to the fourth threaded rod 342, the outer surface of the bending frame 341 is provided with a bending rod 343, one bending frame 341 has three bending rods 343, the bending rod 343 is used as a support point for bending the preloaded tendon 4, and the bending rod 343 in the middle is fixedly connected to the bending frame 341, the bending rods 343 at both ends are slidably connected to the bending frame 341, and the fourth threaded rod 342 and the bending rod 343 are connected to the bending frame 341. 43 is sleeved, and the bending rods 343 and the bending frame 341 at both ends are connected by threads, the threads at both ends of the fourth threaded rod 342 are in opposite directions, the bending frame 341 is slidably connected with the fixing frame 32 and the second connecting frame 33, the bending rod 343 and the fixing frame 32 are slidably connected, and the bending rods 343 at the upper and lower ends are driven to move on the bending frame 341 by rotating the fourth threaded rod 342, so that the spacing between the bending rods 343 changes, which is convenient for bending preload reinforcement 4 of different specifications.

[0049] See also Fig.10 and Fig.11 As shown, the adjustment mechanism 35 includes a second connecting block 351, the second connecting block 351 and the upper end of the bending frame 341 are fixedly connected, the inner cavity of the second connecting block 351 is slidably connected with a second plug rod 352, the outer surface of the second plug rod 352 is sleeved with a first spring 353, the outer surface of the second plug rod 352 is fixedly installed with a fixing ring 354, the fixing ring 354 is located in the inner cavity of the second connecting block 351, the outer surface of the fixing frame 32 is fixedly installed with a fixing strip 355, the outer surface of the fixing strip 355 is provided with a second limiting hole 356, the second plug rod 352 and the second limiting hole 356 are inserted, the first spring 353 is located in the fixing ring 35 4 and the inner wall of the second connecting block 351, the second connecting block 351 and the fixing frame 32 are slidably connected. When adjusting the height of the bending mechanism 34, the second plug rod 352 is disengaged from the second limiting hole 356 by pulling the second plug rod 352. At this time, the second connecting block 351 is moved to drive the bending frame 341 to move. When it reaches a suitable position, the fixing ring 354 is moved toward the fixing strip 355 under the elastic force of the first spring 353, so that the second plug rod 352 is again engaged with the second limiting hole 356, so that the bending mechanism 34 is fixed on the fixing frame 32, so that the height of the bending mechanism 34 can be adjusted according to the bending requirements of the preloaded rib 4.

[0050] See also Fig.10 and Fig.13As shown, the disassembly mechanism 36 includes a fixing rod 361, which is fixedly connected to the bottom end of the second connecting frame 33, and a slot 362 is provided at one end of the fixing rod 361 away from the second connecting frame 33. A second fixing block 363 is fixedly installed on the outer surface of the fixing frame 32, and an elastic rod 364 is slidably connected to the inner cavity of the second fixing block 363. A block 365 is fixedly installed at the bottom end of the elastic rod 364. A second spring 366 is sleeved on the outer surface of the elastic rod 364. The second spring 366 is located between the second fixing block 363 and the block 365. The block 365 and the slot 362 are plugged together, and the alarm mechanism 37 The slider 371 includes a slider 371, the slider 371 is slidably connected to the fixing frame 32, a button 372 is provided on the lower surface of the slider 371, an alarm 373 is fixedly installed on the upper surface of the slider 371, the button 372 and the alarm 373 are electrically connected, a third fixing block 374 is fixedly installed on the outer surface of the fixing frame 32, a third spring 375 is fixedly connected to the outer surface of the third fixing block 374, the button 372 is directly above the elastic rod 364, one end of the third spring 375 away from the third fixing block 374 contacts the slider 371, the pressing of the button 372 controls the alarm 373 to sound an alarm, and the disassembly and assembly machine The structure 36 connects the fixing frame 32 and the second connecting frame 33, and can prevent unplanned removal at the same time. The alarm mechanism 37 can sound an alarm when unplanned removal occurs. When removing, the slider 371 is moved so that the button 372 is not directly above the elastic rod 364. At this time, the third spring 375 is compressed, and the slider 371 is close to the third fixing block 374. At this time, the elastic rod 364 is pulled to disengage the card block 365 and the card slot 362. At this time, the fixing rod 361 is taken out of the inner cavity of the fixing frame 32, that is, the second connecting frame 33 and the fixing frame 32 are separated, which is convenient for multiple use. When installing, the card slot needs to be 362 and the card block 365 can be plugged in, and the elastic force of the second spring 366 makes the elastic rod 364 move downward in the inner cavity of the second fixed block 363 to keep the card block 365 and the card slot 362 plugged in. When it is not planned to be dismantled, the slider 371 makes the button 372 just above the elastic rod 364 under the elastic force of the third spring 375. The movement of the elastic rod 364 will contact the button 372, so that the button 372 is pressed under the squeezing of the elastic rod 364, so that the alarm 373 sounds an alarm, which improves the staff's maintenance of the equipment and ensures the tightness of the connection between the second connecting frame 33 and the fixed frame 32.

[0051] In summary, the position of the bending component 3 is kept fixed by the clamping component 2, the bending component 3 is used to bend the preloaded rib 4, and the bending component 3 can be quickly disassembled and assembled, so that the preloaded rib 4 can be removed after being bent. The bending component 3 can adjust the bending height of the preloaded rib 4, and bend bending components 3 of different specifications. The support legs 12 are used to support the support platform 11, the balance inspection mechanism 13 is used to detect the horizontality of the support platform 11, and the lifting mechanism 14 is used to adjust the horizontality of the support platform 11 to keep the support platform 11 horizontal. The first limiting hole 15 is used to be plugged into the clamping component 2 to keep the bending component 3 fixed, and the adjusting block 23 is driven to move in the inner cavity of the clamping frame 21 by rotating the third threaded rod 22. , after the clamping block 24 is expanded, the third threaded rod 22 is rotated again to shrink the clamping block 24, and the first insertion rod 25 and the first limiting hole 15 are inserted into each other, so that the bending assembly 3 on the first connecting frame 26 is fixed at a fixed position of the support platform 11. After bending, the clamping assembly 2 can also be quickly removed from the pedestal assembly 1, and the pedestal assembly 1 can be used as a bottom template during subsequent pouring. The fixing frame 32 and the second connecting frame 33 are connected by the disassembly and assembly mechanism 36, which facilitates the removal of the second connecting frame 33, so that the bending mechanism 34 can be moved out on one side of the preload reinforcement 4. The adjustment mechanism 35 is used to adjust the height of the bending mechanism 34, and the alarm mechanism 37 is used to sound an alarm when the second connecting frame 33 and the fixing frame 32 are separated unplanned.

[0052] Obviously, those skilled in the art can make various changes and modifications to the present invention without departing from the spirit and scope of the present invention. Thus, if these modifications and variations of the present invention fall within the scope of the claims of the present invention and their equivalents, the present invention is also intended to include these modifications and variations.

[0053] What has been described above are only preferred specific implementation methods of the embodiments of the present application, but the protection scope of the present application is not limited thereto. Any technician familiar with the technical field can make equivalent substitutions or changes based on the technical solution and concept of the present application within the technical scope disclosed in the present application, which should be covered by the protection scope of the present application.

Claims

1. A bending device for reducing the prestress loss of a precast beam using a fold line pretensioning method, comprising a pedestal assembly (1), characterized in that: A clamping assembly (2) is placed on the upper surface of the pedestal assembly (1), a bending assembly (3) is fixedly mounted on the upper surface of the clamping assembly (2), and a pre-tightening rib (4) is provided in the inner cavity of the bending assembly (3); The bending assembly (3) comprises a second connecting plate (31), a fixing frame (32) is fixedly mounted on the upper surface of the second connecting plate (31), a second connecting frame (33) is arranged on one side of the fixing frame (32), a bending mechanism (34) is slidably connected to the inner cavity of the fixing frame (32), an adjusting mechanism (35) is arranged at the upper end of the fixing frame (32), a disassembly mechanism (36) is arranged at the lower end of the fixing frame (32), and an alarm mechanism (37) is arranged above the disassembly mechanism (36).

2. A bending device for reducing the prestress loss of a precast beam using a fold line pretensioning method as claimed in claim 1, characterized in that: The bending mechanism (34) comprises a bending frame (341), the inner cavity of the bending frame (341) is rotatably connected with a fourth threaded rod (342), the outer surface of the bending frame (341) is provided with a bending rod (343), one bending frame (341) has three bending rods (343), the bending rod (343) in the middle portion is fixedly connected to the bending frame (341), the bending rods (343) at both ends are slidably connected to the bending frame (341), the fourth threaded rod (342) and the bending rod (343) are sleeved, and the bending rods (343) at both ends are connected to the bending frame (341) by threads, the threads at both ends of the fourth threaded rod (342) are in opposite directions, the bending frame (341) is slidably connected to the fixed frame (32) and the second connecting frame (33), and the bending rod (343) is slidably connected to the fixed frame (32).

3. A bending device for reducing the prestress loss of a precast beam using a fold line pretensioning method as claimed in claim 2, characterized in that: The adjusting mechanism (35) comprises a second connecting block (351), the second connecting block (351) and the upper end of the bending frame (341) are fixedly connected, the inner cavity of the second connecting block (351) is slidably connected with a second plug rod (352), the outer surface of the second plug rod (352) is sleeved with a first spring (353), the outer surface of the second plug rod (352) is fixedly installed with a fixing ring (354), the fixing ring (354) is located in the inner cavity of the second connecting block (351), the outer surface of the fixing frame (32) is fixedly installed with a fixing strip (355), the outer surface of the fixing strip (355) is provided with a second limiting hole (356), the second plug rod (352) and the second limiting hole (356) are inserted into each other, the first spring (353) is located between the fixing ring (354) and the inner wall of the second connecting block (351), and the second connecting block (351) and the fixing frame (32) are slidably connected.

4. The bending device for reducing the prestress loss of the precast beam by the fold line pretensioning method according to claim 1, characterized in that: The disassembly and assembly mechanism (36) comprises a fixing rod (361), wherein the fixing rod (361) is fixedly connected to the bottom end of the second connecting frame (33), a clamping groove (362) is provided at one end of the fixing rod (361) away from the second connecting frame (33), a second fixing block (363) is fixedly installed on the outer surface of the fixing frame (32), an inner cavity of the second fixing block (363) is slidably connected to an elastic rod (364), a clamping block (365) is fixedly installed at the bottom end of the elastic rod (364), a second spring (366) is sleeved on the outer surface of the elastic rod (364), the second spring (366) is located between the second fixing block (363) and the clamping block (365), and the clamping block (365) and the clamping groove (362) are plugged into each other.

5. A bending device for reducing the prestress loss of a precast beam using a fold line pretensioning method as claimed in claim 4, characterized in that: The alarm mechanism (37) comprises a slider (371), the slider (371) and the fixing frame (32) are slidably connected, a button (372) is arranged on the lower surface of the slider (371), an alarm (373) is fixedly mounted on the upper surface of the slider (371), the button (372) and the alarm (373) are electrically connected, a third fixing block (374) is fixedly mounted on the outer surface of the fixing frame (32), a third spring (375) is fixedly connected to the outer surface of the third fixing block (374), the button (372) is located directly above the elastic rod (364), one end of the third spring (375) away from the third fixing block (374) contacts the slider (371), and pressing the button (372) controls the alarm (373) to sound an alarm.

6. The bending device for reducing the prestress loss of the precast beam by the fold line pretensioning method according to claim 1, characterized in that: The pedestal assembly (1) comprises a support platform (11), support legs (12) are fixedly mounted at four corners of the support platform (11), a balance check mechanism (13) is arranged in the middle of the support platform (11), a lifting mechanism (14) is arranged on the lower surface of the support platform (11), and first limit holes (15) are arranged on both sides of the support platform (11).

7. A bending device for reducing the prestress loss of a precast beam using a fold line pretensioning method as claimed in claim 6, characterized in that: The balance inspection mechanism (13) comprises a detection plate (131), a slide groove (132) is provided on the lower surface of the detection plate (131), a slide frame (133) is slidably connected to the inner cavity of the slide groove (132), a detection frame (134) is fixedly installed in the middle part of the slide frame (133), a moving block (135) is slidably connected to the inner cavity of the detection frame (134), a gravity block (136) is fixedly installed in the middle position of the bottom of the moving block (135), a pointer (137) is fixedly installed on the outer surface of the moving block (135), rollers (138) are rotatably connected to the two ends of the moving block (135), and the rollers (138) are rotatably connected to the inner cavity of the detection frame (134). The inner cavity at the bottom end of the detection frame (134) is rotatably connected to a first threaded rod (139), the first threaded rod (139) and the slide (133) are rotatably connected, the two ends of the first threaded rod (139) are sleeved with detection blocks (1310), the detection block (1310) and the first threaded rod (139) are connected by threads, and the threads at the two ends of the first threaded rod (139) are in opposite directions, a detection rod (1311) is fixedly installed on the outer surface of the detection block (1310) close to the middle of the detection frame (134), the detection rod (1311) and the two ends of the moving block (135) are in contact, and when the detection plate (131) is horizontal, the pointer (137) points to the middle part of the detection frame (134).

8. A bending device for reducing the prestress loss of a precast beam using a fold line pretensioning method as claimed in claim 7, characterized in that: The lifting mechanism (14) comprises a support plate (141), a first fixing block (142) is fixedly mounted on the upper surface of the support plate (141), two first fixing blocks (142) are arranged on one support plate (141), the first fixing blocks (142) are symmetrically distributed on the support plate (141), a lifting block (143) is slidably connected to the inner cavity of the first fixing block (142), a second threaded rod (144) is sleeved on the inner cavity of the first fixing block (142), the second threaded rod (144) and the first fixing block (142) are connected by threads, the threads at two ends of the second threaded rod (144) are in opposite directions, and the lifting block (143) is slidably connected to the inner cavity of the first fixing block (142), and the lifting block (143) is slidably connected to the inner cavity of the first fixing block (142). The two ends of the lifting block (143) are rotatably connected to the first connecting strips (145), the middle part of the first connecting strip (145) is rotatably connected to the second connecting strip (146), the end of the second connecting strip (146) away from the first connecting strip (145) is rotatably connected to the support plate (141), the end of the first connecting strip (145) away from the lifting block (143) is rotatably connected to the first connecting block (147), the upper surface of the first connecting block (147) is fixedly installed with a first connecting plate (148), the first connecting plate (148) and the support platform (11) are fixedly connected, and the lower surfaces of the support plate (141) and the support leg (12) are flush.

9. The bending device for reducing the prestress loss of the precast beam by the fold line pretensioning method as claimed in claim 1, characterized in that: The clamping assembly (2) comprises a clamping frame (21), the inner cavity of the clamping frame (21) is rotatably connected to a third threaded rod (22), the inner cavity of the clamping frame (21) is slidably connected to an adjusting block (23), one end of the adjusting block (23) away from the clamping frame (21) is fixedly mounted with a clamping block (24), the outer surface of the clamping block (24) is fixedly mounted with a first insertion rod (25), the first insertion rod (25) is inserted into a first limiting hole (15), the upper surface of the clamping frame (21) is fixedly mounted with a first connecting frame (26), the first connecting frame (26) is fixedly connected to a second connecting plate (31), the adjusting block (23) and the third threaded rod (22) are connected by threads, and the threads at both ends of the third threaded rod (22) are in opposite directions.

10. A method for reducing the prestress loss of a precast beam using a fold line prestressing method, performed by a bending device for reducing the prestress loss of a precast beam using a fold line prestressing method according to any one of claims 1 to 9, characterized in that: The following steps are involved: S1. Optimizing the bending device, by adjusting the pedestal assembly (1), the bending assembly (3) is kept horizontal when bending the prestressing tendon (4), ensuring that the prestressing tendon (4) is in the correct position during the tensioning process, and making the prestress of the prestressing tendon (4) evenly distributed; S2. Fixing the position of the bending component (3) by means of the clamping component (2) to prevent the bending component (3) from being offset when the bending component (3) is being bent, so that the preloaded rib (4) maintains a predetermined trajectory during the bending process, and the geometric shape after bending complies with the design requirements; S3. The bending assembly (3) can be quickly installed and disassembled, which facilitates the reuse of the prestressing bar (4) after bending. The bending height of the bending assembly (3) can be adjusted, and different types of prestressing bars (4) can be bent, thereby improving the fault tolerance of the bending assembly (3). The optimized structure can reduce the prestress loss of the precast beam using the fold line prestressing method.

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