Temporary tensioning construction method for portal pier cap beam prefabricated segment

Abstract

The application discloses a temporary tension construction method of portal pier cap beam prefabricated segments, which is characterized by the following steps: setting temporary tension tools on the side tension holes in the longitudinal direction of the corresponding prefabricated segments, positioning the temporary tension tools by the embedded cooperation of the setting installation parts and the installation holes, adopting the first finish rolling threaded steel to pass through the side through holes of the temporary tension tools in the longitudinal direction, adopting the second finish rolling threaded steel to pass through the main tension plates in the transverse direction to realize the prestress setting mode between the prefabricated segments, replacing the post-cast concrete tooth blocks on the two sides of the original design portal pier cap beam, avoiding the risk of accidents caused by the easy falling of the post-cast concrete tooth blocks in the subsequent bridge use, and the temporary tension tools are convenient in material selection, simple in installation, solid and durable, can be used for I-beams and box beams respectively, and have wide applicability, and can still be sold as waste materials after use, so that the economic benefits are considerable.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of municipal bridge construction, and more particularly to a temporary tensioning construction method for a portal pier cap beam prefabricated segment. BACKGROUND

[0002] The lower structure portal pier prefabricated segment installation construction needs to apply temporary prestress in the beam splicing process. In actual construction, the top temporary prestress is applied through a hanging beam, and the bottom cavity is applied through post-poured concrete teeth. In order to ensure that the segment matching surface pressure reaches the design requirement, temporary prestress needs to be added on both sides of the segment. The I-beam type portal pier conflicts with the position of the original design post-poured concrete teeth due to the installation position of the I-beam, and the external leakage of the post-poured concrete teeth affects the appearance of the I-beam type and box beam type portal pier segment beam, which cannot meet the requirements of the site construction. Moreover, the original design post-poured concrete teeth need to be poured twice, which has low efficiency, increases the cost of raw materials such as steel and concrete, and the post-poured teeth are prone to fall off in the later use of the bridge. SUMMARY

[0003] An object of the present application is to solve at least the above problems and to provide at least the advantages to be described later.

[0004] Another object of the present application is to provide a temporary tensioning construction method for a portal pier cap beam prefabricated segment to solve the technical problem that the post-poured concrete teeth set by the prior art are troublesome to install and remove, and are not conducive to subsequent efficient construction.

[0005] In order to achieve these objects and other advantages according to the present application, a temporary tensioning construction method for a portal pier cap beam prefabricated segment is provided, comprising the following steps:

[0006] S1, prefabricate segments and cast-in-place segments of a portal pier cap beam, and set side tensioning holes in the middle of the prefabricated segments and cast-in-place segments along the longitudinal direction of the bridge, respectively, two groups of side tensioning holes are set in the vertical direction, and non-circular installation holes are symmetrically reserved in the middle of the upper and lower two side tensioning holes on the front and rear surfaces of the prefabricated segments and cast-in-place segments in the longitudinal direction of the bridge, and the opening direction of the installation hole faces the corresponding side surface;

[0007] S2, after the prefabricated segments are transported to the site, hang the temporary tensioning tool on the ground, and the temporary tensioning tool comprises:

[0008] A pair of fixed plates are oppositely and parallelly arranged, the fixed plates are in the shape of a cross as a whole in the plane, one pair of opposite sides are set as support portions, and the other pair of opposite sides are set as tensioning portions, the length of the support portion is greater than that of the tensioning portion, and a pair of through side holes are symmetrically set on each pair of tensioning portions, and the size and spacing of the two side holes are consistent with those of the two side tensioning holes in the vertical direction;

[0009] The support plate comprises a main support plate and a side support plate, the main support plate is connected between a pair of fixing plates along the length direction of the fixing plate and is symmetrically arranged on both sides of the support part, the length of the main support plate is consistent with the length of the fixing plate, a pair of side support plates is symmetrically connected between each pair of tensioning parts, a pair of side support plates is symmetrically connected between the middle part of a pair of main support plates and a pair of fixing plates, and the inner side of each side support plate is connected with the corresponding surface of the main support plate;

[0010] The main tensioning plate is provided in pairs, each main tensioning plate covers the end part of a pair of support parts and a pair of main support plates located on the same side, and a pair of main through holes is provided in the center of a pair of main tensioning plates;

[0011] The mounting part is fixed in the middle part of one of the fixing plates, and the mounting part is arranged in cooperation with the mounting hole;

[0012] When the temporary tensioning tool is installed, the length direction of the support part is aligned on the horizontal line, the mounting part is aligned and inserted into the mounting hole, at this time, the side through hole is aligned with the side tensioning hole on the corresponding prefabricated segment, a first finished rolled threaded steel is inserted into each group of side tensioning holes and side through holes located on the same longitudinal bridge direction, anchoring and tensioning are performed;

[0013] S3, in the transverse bridge direction, a second finished rolled threaded steel is inserted through the main through hole on the main tensioning plate to connect adjacent temporary tensioning tools, anchoring and tensioning are performed;

[0014] S4, after the construction of the bent cap is completed, the first finished rolled threaded steel and the second finished rolled threaded steel are removed, and the temporary tensioning tool is taken down for recycling, and the mounting hole is filled.

[0015] Preferably, after step S3 is completed, a protective cloth is arranged along the longitudinal bridge direction between adjacent prefabricated segments.

[0016] Preferably, the mounting part is a trapezoidal table structure arranged vertically outwardly from the fixing plate, the bottom surface of the mounting part is square and the larger end of the cross-sectional dimension is fixedly connected with the corresponding fixing plate, and the mounting part can slide relative to the mounting hole.

[0017] Preferably, the temporary tensioning tool is commonly connected with a lifting ring outwardly on the outer side of a pair of side support plates located on the same side, and the temporary tensioning tool is moved by grabbing the lifting ring when the temporary tensioning tool is installed and removed.

[0018] Preferably, when the temporary tensioning tool is installed, the lifting ring is located on the lower side of the fixing plate, and in step S4, the temporary tensioning tool is recycled by setting a hook recycling device below the prefabricated segment, and the hook recycling device comprises:

[0019] The bottom frame is provided longitudinally, and the bottom of the bottom frame is provided with traveling wheels at both ends downward respectively, and the upper end of the bottom frame is provided with a sleeve along the longitudinal direction, and the outer wall of the sleeve is provided with an outer limiting hole opposite along the radial direction, and the outer limiting hole is arranged along the length direction at intervals;

[0020] The C-shaped frame is provided with one corresponding to each end of the sleeve, and the opening faces the horizontal bridge direction of the central axis, and the C-shaped frame comprises a lower sliding rod, a connecting rod and an upper sliding rod which are connected in sequence, the lower sliding rod is horizontally provided, the connecting rod is downwardly provided and located outside the longitudinal direction of the prefabricated segment, and the upper sliding rod is upwardly and obliquely provided away from the connecting rod, the size of the outer end of the upper sliding rod is smaller than that of the lifting ring and is at the same height as the lifting ring, the end of the lower sliding rod facing the sleeve is provided with an inner limiting hole at intervals along the length direction, the inner limiting hole is provided through the radial direction of the lower sliding rod and is consistent with the size of the outer limiting hole, the end of the lower sliding rod facing the sleeve penetrates into the sleeve and is slidingly connected with the sleeve to adjust the distance between the two C-shaped frames, the minimum distance between the two connecting rods is greater than the maximum width of the prefabricated segment, the minimum distance between the outer ends of the pair of upper sliding rods is smaller than the width of the prefabricated segment at the position provided with the side tension hole, and a bolt is inserted into the pair of inner limiting holes and the pair of outer limiting holes to temporarily fix and limit the position of the lower sliding rod;

[0021] When the temporary tensioning tool is recovered, the hook recovery device is erected below the prefabricated segment and moved to the longitudinal position corresponding to the temporary tensioning tool along the horizontal bridge direction, then the bolt is removed, the C-shaped frame is moved along the sleeve in opposite directions until the outer end of the upper sliding rod enters the inner side of the lifting ring and the bolt is screwed, after the first finish rolling threaded steel and the second finish rolling threaded steel corresponding to the current temporary tensioning tool are disassembled, the temporary tensioning tool is hung on the outer end of the upper sliding rod and slides in the inclined direction, the recovery of the current temporary tensioning tool is completed, then the bolt is removed, the C-shaped frame is moved outward to leave a movement space to reach the outside of the next temporary tensioning tool, the bolt is screwed again, the whole hook recovery device is moved to the corresponding position of the next temporary tensioning tool, and the foregoing actions are repeated until the recovery of all the temporary tensioning tools is completed.

[0022] Preferably, the bottom of the prefabricated segment is provided with a mark corresponding to the position of the lifting ring of the temporary tensioning tool, and the hook recovery device is moved and positioned according to the mark.

[0023] Preferably, a camera is provided on the outer side of the bottom frame upward and toward the side where the temporary tensioning tool is located, and a display terminal is provided on the bottom frame, the camera is in communication connection with the display terminal and transmits the shooting image to the display terminal for display.

[0024] Preferably, a shovel is arranged on the outer end of the upper slide rod in the vertical direction upward, the plane of the shovel is parallel to the transverse bridge direction, the shovel can extend into the inner side of the lifting ring, and a vertical telescopic mechanism is further arranged on the base frame, and the middle part of the sleeve pipe is connected to the telescopic end of the vertical telescopic mechanism;

[0025] The hook recovery device is moved to the temporary tensioning tool, the shovel is at the same height as the inner side of the lifting ring at this time, the C-shaped frame is moved inward until the shovel abuts against the surface of the precast segment on the inner side of the lifting ring, the sleeve pipe is jacked upward through the vertical telescopic mechanism after the first finish rolling threaded steel and the second finish rolling threaded steel are removed, the shovel is scooped into the upper end surface of the lifting ring on the side facing the precast segment, the temporary tensioning tool is separated from the corresponding precast segment and falls into the upper slide rod, slides in the inclined direction of the upper slide rod, and then the position of the C-shaped frame relative to the sleeve pipe is reset, the vertical telescopic mechanism is reset, and the hook recovery device is moved to the next temporary tensioning tool as a whole.

[0026] The present application at least includes the following beneficial effects:

[0027] (1) The temporary tensioning construction method of the portal pier cap beam precast segment of the present application sets a temporary tensioning tool on the side tensioning hole in the longitudinal bridge direction of the corresponding precast segment, the temporary tensioning tool is positioned through the embedded cooperation of the arranged mounting part and the mounting hole, the first finish rolling threaded steel is used to pass through the side of the temporary tensioning tool in the longitudinal bridge direction, and the second finish rolling threaded steel is used to pass through the main tensioning plate in the transverse bridge direction, thereby replacing the post-cast concrete tooth blocks on both sides of the original design portal pier cap beam, and avoiding the risk that the post-cast concrete tooth blocks are easily detached to cause accidents in subsequent bridge use.

[0028] (2) The temporary tensioning tool is removed after the permanent tensioning of the portal pier cap beam is completed, does not conflict with the installation position of the I beam, and after removal, the grouting material is used to adjust the color and fill the square hole, and has no influence on the appearance of the subsequent portal pier cap beam.

[0029] (3) The temporary tensioning tool is convenient to obtain materials, simple to install, solid and durable, can be used for I beams and box beams respectively, has wide applicability, and can still be sold as waste materials after use, and has considerable economic benefits.

[0030] Other advantages, objects, and features of the present application will be partly embodied by the following description, and partly understood by those skilled in the art through research and practice of the present application. BRIEF DESCRIPTION OF DRAWINGS

[0031] Figure 1 It is a front view of the temporary tensioning tool of the present application;

[0032] Figure 2A top view structural diagram of the temporary tensioning tool of the present application;

[0033] Figure 3 A side view structural diagram of the temporary tensioning tool of the present application installed on the bent cap;

[0034] Figure 4 A bottom view structural diagram of the temporary tensioning tool of the present application installed on the bent cap;

[0035] Figure 5 A structural diagram of the hook recycling device of one embodiment of the present application installed below the bent cap;

[0036] The description of the drawings: 1, bent cap, 2, temporary tensioning tool, 3, first finished threaded steel, 4, second finished threaded steel, 5, fixed plate, 6, support part, 7, tensioning part, 8, side through hole, 9, main support plate, 10, side support plate, 11, main tensioning plate, 12, main through hole, 13, installation part, 14, lifting ring, 15, bottom frame, 16, walking wheel, 17, sleeve, 18, outer limiting hole, 19, lower sliding rod, 20, connecting rod, 21, upper sliding rod, 22, inner limiting hole, 23, bolt, 24, camera, 25, shovel piece, 26, vertical telescopic mechanism, 27, display terminal. DETAILED DESCRIPTION

[0037] The present application will be further described in detail below with reference to the accompanying drawings, so that those skilled in the art can implement the present application according to the description.

[0038] It should be noted that the experimental methods described in the following embodiments are all conventional methods unless otherwise specified, and the reagents and materials can be obtained from commercial channels unless otherwise specified; in the description of the present application, the terms "lateral", "longitudinal", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer" and the like indicate the orientation or positional relationship shown in the drawings, which is only for the convenience of describing the present application and simplifying the description, and does not indicate or imply that the devices or elements referred to must have a particular orientation, be constructed and operated in a particular orientation, therefore it cannot be understood as a limitation on the present application.

[0039] As Figures 1-4 shown, the present application provides a temporary tensioning construction method for a portal pier bent cap prefabricated segment, including the following steps, for the convenience of description, the arrangement and installation direction of the prefabricated segment along the bridge is the transverse bridge direction:

[0040] S1, the prefabricated segment and the cast-in-place segment of the construction portal pier cap beam 1 are provided with side tension holes penetrating in the longitudinal bridge direction in the middle of the prefabricated segment and the cast-in-place segment, respectively, two groups of side tension holes are provided in the vertical direction, the prefabricated segment and the cast-in-place segment are symmetrically reserved with non-circular mounting holes in the middle of the upper and lower side tension holes on the front and rear surfaces in the longitudinal bridge direction, and the opening direction of the mounting hole is outward to the corresponding side surface. The size and the spacing of the subsequently arranged temporary tensioning tool 2 and the side through hole 8 are matched with the position and the size of the side tension hole.

[0041] S2, after the prefabricated segment is transported to the site, the temporary tensioning tool 2 is hung on the ground, and the temporary tensioning tool 2 comprises:

[0042] a pair of fixed plates 5 are oppositely and parallelly arranged, the fixed plate 5 is in the form of a cross as a whole in the plane, one pair of opposite sides are provided as support portions 6, and the other pair of opposite sides are provided as tensioning portions 7, the length of the support portion 6 is greater than that of the tensioning portion 7, a pair of through side through holes 8 are symmetrically provided on each tensioning portion 7, and the size and the spacing of the side through holes 8 on the two sides are consistent with the size and the spacing of the two side tension holes in the vertical direction;

[0043] a support plate comprises a main support plate 9 and a side support plate 10, the main support plate 9 is connected between the pair of fixed plates 5 in the length direction of the fixed plate 5 and is symmetrically arranged on the two sides of the support portion 6, the length of the main support plate 9 is consistent with the length of the fixed plate 5, a pair of side support plates 10 are symmetrically connected between each pair of tensioning portions 7, a pair of side support plates 10 are symmetrically connected between the center of the pair of main support plates 9 and the pair of fixed plates 5, and the inner side of each side support plate 10 is connected with the corresponding surface of the main support plate 9;

[0044] a pair of main tensioning plates 11 are provided, each main tensioning plate 11 is connected at the end of the pair of support portions 6 and the pair of main support plates on the same side, and a pair of main through holes 12 are provided in the center of the pair of main tensioning plates 11;

[0045] an installation portion 13 is fixed in the middle of one of the fixed plates 5, and the installation portion 13 is matched with the mounting hole;

[0046] the fixed plate 5 and the main tensioning plate 11 on the outer side are made of 16mm steel plate, the support plate on the inner side is made of 10mm steel plate, and they are welded with each other, when the temporary tensioning tool 2 is installed, the length direction of the support portion 6 is aligned on the horizontal line, the installation portion 13 is aligned and inserted into the mounting hole, at this time, the side through hole 8 is aligned with the side tension hole on the prefabricated segment, one φ25 first finished rolling threaded steel 3 is inserted into each group of side tension holes and side through holes on the same longitudinal bridge direction, two φ25 first finished rolling threaded steels 3 are inserted into each temporary tensioning tool 2, anchoring and tensioning are performed, and the tension is 100KN.

[0047] S3, in the transverse bridge direction, a second φ32 finish rolling threaded steel 4 is passed through the main through hole 12 on the main tension plate 11 to connect the adjacent temporary tensioning tool 2, anchor and tension to the design value.

[0048] S4, after the construction of the bent cap 1 is completed, the first finish rolling threaded steel 3, the second finish rolling threaded steel 4 and the temporary tensioning tool 2 are removed for recycling, and the installation hole is filled with grouting material to have no influence on the appearance of the subsequent portal pier bent cap 1.

[0049] The temporary tensioning construction method of the portal pier bent cap 1 prefabricated segment of the application sets the temporary tensioning tool 2 on the side tensioning hole in the longitudinal bridge direction of the corresponding prefabricated segment, the temporary tensioning tool 2 is positioned by the embedded cooperation of the installation part 13 and the installation hole, in the longitudinal bridge direction, the first finish rolling threaded steel 3 is passed through the side through hole 8 of the temporary tensioning tool 2, in the transverse bridge direction, the second finish rolling threaded steel 4 is passed through the main tension plate 11 to realize the prestress setting mode between the prefabricated segments, replace the traditional original design of the post-cast concrete tooth block on both sides of the portal pier bent cap 1, avoid the risk of accidents caused by the easy falling of the traditional design of the post-cast concrete tooth block in the subsequent bridge use, and the temporary tensioning tool 2 is convenient to use, easy to install, durable, can be used for I-beam and box girder respectively, has wide applicability, the number of the original design of the post-cast tooth block is 1288 for I-beam and box girder, the unit price of single subcontracting and pouring is 320 yuan per piece, the material and labor cost of the temporary tensioning tool 2 of the present application is about 1000 yuan per piece, 56 pieces are needed in the present project, and after use, the waste can still be sold, through the comparison, the economic benefit is considerable.

[0050] In another technical solution, after step S3 is completed, a protective cloth is wrapped along the longitudinal bridge direction between the adjacent prefabricated segments.

[0051] By setting the protective cloth, the maintenance of the prefabricated segment is facilitated, and the position of the temporary tensioning tool 2 is protected to a certain extent.

[0052] In another technical solution, as shown in Figure 2 , 4 The installation part 13 is a trapezoidal table structure vertically outwardly arranged on the fixed plate 5, the bottom surface of the installation part 13 is square and the larger end of the cross-sectional dimension is fixedly connected with the corresponding fixed plate 5, and the installation part 13 can slide relative to the installation hole.

[0053] By setting the installation part 13 and the installation hole as a trapezoidal hole with a square bottom surface, the alignment of the installation direction of the temporary tensioning tool 2 is facilitated, the installation part 13 is slidably inserted into the installation hole, and when the fixing effect of the first finished threaded steel 3 and the second finished threaded steel 4 is lost, the temporary tensioning tool 2 is also facilitated to be removed. The originally designed post-poured concrete tooth block protrusion affects the appearance of the I-beam type and box-beam type portal pier cap beam 1, and after the temporary tensioning tool 2 is removed, the square hole is filled with grouting material to adjust the color, which has no effect on the appearance of the subsequent portal pier cap beam 1.

[0054] In another technical solution, as shown in Figures 1-2 the temporary tensioning tool 2 is commonly connected with a lifting ring 14 outside a pair of side support plates located on the same side. When the temporary tensioning tool 2 is installed and removed, the temporary tensioning tool 2 is moved by grabbing the lifting ring 14. By setting the lifting ring 14, the temporary tensioning tool 2 is facilitated to be lifted, transferred and installed.

[0055] In another technical solution, as shown in Figure 5 when the temporary tensioning tool 2 is installed, the lifting ring 14 is located below the fixing plate 5, and in step S4, the temporary tensioning tool 2 is recycled by setting a hook recycling device below the prefabricated segment. The hook recycling device comprises:

[0056] a chassis 15 is arranged in the longitudinal direction, and two walking wheels 16 are arranged at the bottom of the chassis 15, respectively. A sleeve 17 is arranged at the upper end of the chassis 15 in the longitudinal direction, and an outer limiting hole 18 is arranged on the outer wall of the sleeve 17 in the radial direction, and the outer limiting hole 18 is arranged in the length direction.

[0057] The C-shaped frame is provided with one at each end of the sleeve 17, and the opening faces the horizontal bridge direction central axis. The C-shaped frame comprises a lower sliding rod 19, a connecting rod 20 and an upper sliding rod 21 which are sequentially connected and arranged. The lower sliding rod 19 is horizontally arranged. The connecting rod 20 is vertically arranged and located at the outer side of the longitudinal bridge direction of the prefabricated segment. The upper sliding rod 21 is obliquely arranged upwards in the direction away from the connecting rod 20. The size of the outer end of the upper sliding rod 21 is smaller than the size of the lifting ring 14 and is at the same height as the lifting ring 14. An inner limiting hole 22 is arranged on the end of the lower sliding rod 19 facing the sleeve 17 and is spaced apart along the length direction. The inner limiting hole 22 is radially arranged through the lower sliding rod 19 and is consistent with the size of the outer limiting hole 18. The end of the lower sliding rod 19 facing the sleeve 17 penetrates into the sleeve 17 and is slidably connected with the sleeve 17, so as to adjust the distance between the two C-shaped frames. The minimum distance between the two connecting rods 20 is greater than the maximum width of the prefabricated segment. The minimum distance between the outer ends of the pair of upper sliding rods 21 is smaller than the width of the prefabricated segment at the position provided with the side tension hole. A bolt 23 is inserted into the pair of inner limiting holes 22 and the pair of outer limiting holes 18, so as to temporarily fix and limit the position of the lower sliding rod 19.

[0058] When the temporary tensioning tool 2 is recovered, the hook recovery device is erected below the prefabricated segment, the walking wheel 16 can be locked to fix the position, which is common and does not need to be repeated here. Initially, the distance between the two C-shaped frames is relatively large, so that the C-shaped frame on the base frame 15 can be erected to cross the widest part of the prefabricated segment downward and reach the vertical plane where the temporary tensioning tool 2 is located, and will not be interfered by the first finished threaded steel 3 during the lateral movement. Then, the hook recovery device is moved to the corresponding longitudinal position of the temporary tensioning tool 2, the bolt 23 is removed, the two C-shaped frames are moved towards each other along the sleeve 17, until the outer end of the upper sliding rod 21 enters the inner side of the lifting ring 14, the bolt 23 is screwed, and the relative position of the C-shaped frame at this time is temporarily fixed. After the first finished threaded steel 3 and the second finished threaded steel 4 corresponding to the current temporary tensioning tool 2 are removed, the temporary tensioning tool 2 is hung on the outer end of the upper sliding rod 21 and slides towards the connecting rod 20 in an inclined direction, the mounting portion 13 is separated from the mounting hole, and the height of the sleeve 17 on the base frame 15 can be adjusted to cooperate with the sliding of the temporary tensioning tool 2. The recovery of the current temporary tensioning tool 2 is completed, then the bolt 23 is removed, the C-shaped frame is moved outward to leave space for reaching the next temporary tensioning tool 2, the bolt 23 is screwed again, the hook recovery device is moved to the corresponding position of the next temporary tensioning tool 2, and the above-mentioned actions are repeated until the recovery of all temporary tensioning tools 2 is completed. By setting the hook recovery device to recover the temporary tensioning tool 2, a pair of temporary tensioning tools 2 on both sides can be recovered at a time, without the need to frequently start and adjust the crane to transport construction personnel to the high place to collect, and the risk of falling of the temporary tensioning tool 2 on the other side or the need for additional construction personnel to cooperate with the removal is avoided, which significantly improves the recovery efficiency and construction safety.

[0059] In another technical solution, a mark is arranged on the bottom of the prefabricated segment corresponding to the position of the lifting ring 14 of the temporary tensioning tool 2, and the hook recovery device is moved and positioned according to the mark. By setting the mark or symbol, the hook recovery device can be quickly moved to the specified position, further improving the recovery efficiency of the temporary tensioning tool 2.

[0060] In another technical solution, as shown in Figure 5 The outer side of the base frame 15 is provided with a camera 24 upward and towards the side where the temporary tensioning tool 2 is located, and a display terminal 27 is arranged on the base frame 15. The camera 24 is in communication connection with the display terminal 27 and transmits the photographed image to the display terminal 27 for display.

[0061] The installation position of the display terminal 27 is set according to construction requirements, and can be arranged at the middle part of the sleeve pipe 17, so that the construction personnel can observe the display terminal 27, and better master the position of the outer end of the upper slide rod 21, i.e. the end far away from the connecting rod 20, relative to the lifting ring 14.

[0062] In another technical solution, as shown in the drawings, a shovel blade 25 is arranged at the outer end of the upper slide rod 21 in the vertical upward direction, the plane of the shovel blade 25 is parallel to the horizontal bridge direction, the shovel blade 25 can extend into the inner side of the lifting ring 14, and a vertical telescopic mechanism 26 is further arranged on the base frame 15, and the middle part of the sleeve pipe 17 is connected to the telescopic end of the vertical telescopic mechanism 26. Figure 5

[0063] The hook recovery device is moved to the temporary tensioning tool 2, at this time, the shovel blade 25 is at the same height as the inner side of the lifting ring 14, the C-shaped frame is moved to the inner side, until the shovel blade 25 abuts against the surface of the precast segment located at the inner side of the lifting ring 14, after the first finish rolling threaded steel 3 and the second finish rolling threaded steel 4 are removed, the sleeve pipe 17 is jacked upward by the vertical telescopic mechanism 26, the shovel blade 25 is scooped into the side of the upper end surface of the lifting ring 14 facing the precast segment, so that the temporary tensioning tool 2 is separated from the corresponding precast segment and falls into the upper slide rod 21, slides along the inclined direction of the upper slide rod 21, and then the position of the C-shaped frame relative to the sleeve pipe 17 is reset, and the vertical telescopic mechanism 26 is reset, and the hook recovery device is moved to the next temporary tensioning tool 2.

[0064] The vertical telescopic mechanism 26 can be a small-sized jack, a push oil cylinder or the like, by arranging the shovel blade 25, when the C-shaped frame is telescopically moved, the shovel blade 25 can better abut against the corresponding surface of the precast segment, so that the orientation of the shovel blade 25 is vertical and parallel to the lifting ring 14, and then the shovel blade 25 is moved upward to hook the lifting ring 14, so that the temporary tensioning tool 2 is hung on the upper slide rod 21 after leaving the installation part 13, the operability of the temporary tensioning tool 2 is improved, and the recovery speed is faster and more stable.

[0065] Although the embodiments of the present application have been disclosed as above, they are not limited to the application listed in the specification and the embodiments, and can be fully applied to various fields suitable for the present application, and other modifications can be easily realized by those skilled in the art, and therefore the present application is not limited to specific details and the drawings shown and described herein, without departing from the general concept defined by the claims and the equivalent scope.​

Claims

1. A temporary tensioning construction method for precast segments of portal pier cap beams, characterized in that, Includes the following steps: S1. For the precast and cast-in-place segments of the construction portal pier cap beam, side tensioning holes are respectively provided in the middle of the precast and cast-in-place segments along the longitudinal direction of the bridge. Two sets of side tensioning holes are arranged vertically at intervals. Non-circular installation holes are symmetrically reserved in the middle of the upper and lower side tensioning holes on the front and rear surfaces of the precast and cast-in-place segments in the longitudinal direction of the bridge. The opening direction of the installation holes faces outwards from the corresponding side. S2. After the precast segments are transported to the site, temporary tensioning tools are installed while they are suspended on the ground. The temporary tensioning tools include: The fixing plates are arranged in pairs opposite and parallel to each other. The fixing plates are cross-shaped in their plane. One pair of opposite sides are set as support parts, and the other pair of opposite sides are set as tensioning parts. The length of the support parts is greater than that of the tensioning parts. Each pair of tensioning parts is symmetrically provided with through holes on the sides. The size and spacing of the through holes on both sides are the same as the size and spacing of the two vertical side tensioning holes. The support plate includes a main support plate and side support plates. The main support plate is connected between a pair of fixed plates along the length of the fixed plates and is symmetrically arranged on both sides of the support. The length of the main support plate is the same as the length of the fixed plates. A pair of side support plates are symmetrically connected between each pair of tensioning parts. A pair of side support plates are symmetrically connected between the middle of a pair of main support plates and a pair of fixed plates. The inner side of each side support plate is connected to the corresponding surface of the main support plate. The main pull plate is provided in pairs, each main pull plate covering and connecting the ends of a pair of support parts and a pair of main support plates located on the same side, and a pair of main through holes are opened through the center of the pair of main pull plates; The mounting part is fixed in the middle of one of the fixing plates. The mounting part is configured to cooperate with the mounting hole and can slide relative to the mounting hole. The temporary tensioning tool has a lifting ring connected to the outside of a pair of side support plates on the same side. When installing and removing the temporary tensioning tool, the tool is moved by grabbing the lifting ring. When installing the temporary tensioning tool, align the length direction of the support part to be on the horizontal line, align the installation part with the insertion hole, and at this time, the side through hole is aligned with the side tensioning hole on the corresponding precast segment. The lifting ring is located on the lower side of the fixing plate. A first fine-rolled threaded steel bar is inserted into each group of side tensioning holes and side through holes located in the same longitudinal direction of the bridge for anchoring and tensioning. S3. On the transverse bridge, a second high-strength threaded steel bar is passed through the main through hole on the main tensioning plate to connect the adjacent temporary tensioning tool, anchor it, and then tension it. S4. After the cap beam construction is completed, the first and second precision-rolled threaded steel bars are removed. Temporary tensioning tools are then removed and reused by using a hook-and-retrieve device installed below the precast segment. The hook-and-retrieve device includes: The base frame has a sleeve installed at its upper end along the longitudinal bridge direction. The outer wall of the sleeve has radially opposite external limiting holes, which are arranged at intervals along the length direction. A C-shaped frame is provided at each end of the sleeve, with the opening facing the central axis of the transverse bridge. The upper end of the C-shaped frame is inclined upward. The outer end of the upper sliding rod is smaller than the size of the lifting ring and is at the same height as the lifting ring. The lower end of the C-shaped frame is provided with inner limiting holes spaced apart along the length direction. The inner limiting holes are the same size as the outer limiting holes. The lower end of the C-shaped frame passes into the sleeve and slides between the sleeve. Bolts are inserted into one pair of inner limiting holes and one pair of outer limiting holes to temporarily fix and limit the position of the lower sliding rod. When retrieving the temporary tensioning tool, the hook retrieval device is set up below the precast segment and moved along the transverse bridge direction to the corresponding longitudinal bridge position of the temporary tensioning tool. The outer end of the upper sliding rod enters the inner side of the lifting ring, and the bolt is tightened. After disassembling the first and second fine-rolled threaded steel bars, the temporary tensioning tool is hung on the outer end of the upper sliding rod and slides along the inclined direction to complete the retrieval of the current temporary tensioning tool and fill the installation hole.

2. The temporary tensioning construction method for precast segments of portal pier cap beams as described in claim 1, characterized in that, After step S3 is completed, protective cloth is installed along the longitudinal bridge direction between adjacent prefabricated segments.

3. The temporary tensioning construction method for precast segments of portal pier cap beams as described in claim 1, characterized in that, The mounting part is a trapezoidal platform structure arranged vertically outward along the fixing plate. The bottom surface of the mounting part is square and the end with the larger cross-sectional dimension is fixedly connected to the corresponding fixing plate.

4. The temporary tensioning construction method for precast segments of portal pier cap beams as described in claim 3, characterized in that, The base frame is arranged along the longitudinal direction of the bridge, and the bottom ends of the base frame are respectively provided with downward-facing wheels; The C-shaped frame includes a lower sliding rod, a connecting rod, and an upper sliding rod connected in sequence. The lower sliding rod is horizontally positioned, the connecting rod is downwardly positioned and located on the outer side of the precast segment in the longitudinal direction, and the upper sliding rod is inclined upwards in a direction away from the connecting rod. The outer end of the upper sliding rod is smaller than the size of the lifting ring and is at the same height as the lifting ring. The lower sliding rod has the inner limiting holes spaced apart along its length at one end facing the sleeve. The lower sliding rod passes into the sleeve and is slidably connected to the sleeve to adjust the spacing between the two C-shaped frames. The minimum distance between the two connecting rods is greater than the maximum width of the precast segment, and the minimum distance between the outer ends of the pair of upper sliding rods is less than the width of the precast segment at the location where the side tensioning hole is provided. When retrieving the temporary tensioning tool, the hook retrieval device is set up below the precast segment and moved along the transverse bridge direction to the corresponding longitudinal bridge position of the temporary tensioning tool. Then, the bolts are removed, and the C-shaped frame is moved towards each other along the sleeve until the outer end of the upper sliding rod enters the inner side of the lifting ring and the bolts are tightened. After disassembling the first and second precision-rolled threaded steel bars corresponding to the current temporary tensioning tool, the temporary tensioning tool is hung on the outer end of the upper sliding rod and slides in the inclined direction to complete the retrieval of the current temporary tensioning tool. Then, the bolts are removed, and the C-shaped frame is moved outward to leave space for movement to reach the outer side of the next temporary tensioning tool. The bolts are tightened again, and the entire hook retrieval device is moved to the corresponding position of the next temporary tensioning tool. The aforementioned actions are repeated until all temporary tensioning tools are retrieved.

5. The temporary tensioning construction method for precast segments of portal pier cap beams as described in claim 4, characterized in that, The bottom of the precast segment is marked at the corresponding position of the lifting ring of the temporary tensioning tool. When the hook and retrieval device is moved, it is moved and positioned according to the marks.

6. The temporary tensioning construction method for precast segments of portal pier cap beams as described in claim 4, characterized in that, A camera is installed on the outer side of the base frame, facing upwards and toward the temporary tensioning tool. A display terminal is installed on the base frame. The camera is connected to the display terminal and transmits the captured images to the display terminal for display.

7. The temporary tensioning construction method for precast segments of portal pier cap beams as described in claim 4, characterized in that, A shovel is provided vertically upward at the outer end of the upper sliding rod. The plane of the shovel is parallel to the transverse direction of the bridge. The shovel can extend into the inner side of the lifting ring. A vertical telescopic mechanism is also provided on the base frame. The middle part of the sleeve is connected to the telescopic end of the vertical telescopic mechanism. Move the hook and retrieval device to the temporary tensioning tool. At this time, the shovel blade and the inner side of the lifting ring are at the same height. Move the C-shaped frame inward until the shovel blade abuts against the surface of the precast segment located on the inner side of the lifting ring. After disassembling the first and second precision-rolled threaded steel bars, lift the sleeve upward through the vertical telescopic mechanism. The shovel blade shovels into the upper end of the lifting ring facing the precast segment, so that the temporary tensioning tool completes the separation from the corresponding precast segment and falls onto the upper sliding rod. Slide along the inclined direction of the upper sliding rod. Then reset the position of the C-shaped frame relative to the sleeve, reset the vertical telescopic mechanism, and move the hook and retrieval device as a whole to the next temporary tensioning tool.

Images