Curved variable cross-section concrete tower column of low-tower cable-stayed bridge and construction method thereof

Abstract

The present application relates to a low tower cable-stayed bridge curved variable cross-section concrete tower column and its construction method, characterized in that a combined connecting cross bar is arranged in the tower column support system; an adjustable temporary counter support frame is arranged; an adjustable assembly type unloading device is used in the tower column closure segment; and a quick connection technology is used in the tower column stiff skeleton segment. The main construction steps include: (1) tower column support arrangement, (2) stiff skeleton construction, (3) tower column steel bar binding, (4) tower column formwork engineering, (5) tower column concrete construction, (6) tower column temporary horizontal internal support construction, and (7) tower column closure segment construction. The low tower cable-stayed bridge variable cross-section arch tower column of the present application has the advantages of fast construction speed, high construction quality, effective cost reduction in practical application, and good technical and economic benefits.

Description

Technical Field

[0001] This invention relates to a variable cross-section concrete bridge tower, and more particularly to a curved variable cross-section concrete tower for a low-tower cable-stayed bridge and its construction method. Background Technology

[0002] With the continuous development of my country's economy and society, my country's bridge construction has achieved remarkable results. Low-tower cable-stayed bridges, due to their combination of rigidity and flexibility and beautiful design, have been widely used in bridge engineering. With the increasing application and development of low-tower cable-stayed bridge structures, more and more bridge projects are adopting variable cross-section arch towers, which places higher demands on quality control during the construction process of low-tower cable-stayed bridges.

[0003] During the construction of low-tower cable-stayed bridges, traditional temporary bracing cannot be dynamically and flexibly moved. During the closure section construction, the unloading device may introduce errors at both ends during unloading, posing certain construction risks. Furthermore, the welding of the concrete tower stiffening frame segments is challenging and requires high positioning accuracy. Therefore, it is essential to research a construction method for variable cross-section arched towers in low-tower cable-stayed bridges that offers fast construction speed, high construction quality, and low construction cost. Summary of the Invention

[0004] The purpose of this invention is to overcome the shortcomings of the prior art and provide a curved variable cross-section concrete tower column for a low-tower cable-stayed bridge and its construction method.

[0005] To achieve the above-mentioned technical objectives, the present invention adopts the following technical solution:

[0006] The construction method for curved variable cross-section concrete tower columns of low-tower cable-stayed bridges includes the following steps:

[0007] Step 1: Tower support arrangement:

[0008] As the tower construction progresses, the tower support erection height is adjusted accordingly; the tower support is placed on the already poured bridge deck, and according to construction requirements, a certain area below the center of the tower is designated as the pole reinforcement zone.

[0009] Step 2: Construction of the rigid frame:

[0010] The rigid frame is laid out and constructed at a 1:1 scale to form a horizontal tripod; the rigid frame is added section by section as the concrete segments of the tower column are raised.

[0011] During docking, the upper part of the front stiffening frame is equipped with a bottom positioning device, the upper part of the rear stiffening frame is equipped with an end positioning device, and the bottom is equipped with a middle positioning device.

[0012] The positioning threaded rod passes through the central positioning device, and both ends are equipped with connecting posts. It is connected and fixed to the sleeves on each positioning device by threads and bolts.

[0013] Among them, the bottom positioning device, the middle positioning device and the end positioning device are equipped with limit terminals on the L-shaped positioning plates and placed in the reserved limit groove of the rigid frame;

[0014] Step 3: Tower column reinforcement binding:

[0015] During the binding of steel bars, a tower crane is used to hoist each bundle onto the tower column using specialized lifting equipment.

[0016] Step 4: Tower Column Formwork Engineering:

[0017] The tower column formwork panel is made of Vesa board, the secondary back ribs of the tower column formwork are made of wooden beams, and the main back ribs of the tower column formwork are made of steel beams. The formwork system is tightened by the tower column support and diagonal bracing is set to support the tower column support.

[0018] Step 5: Concrete construction of the tower column:

[0019] The concrete is delivered using a truck pump, and water is sprayed for curing immediately after the concrete is poured.

[0020] Step Six: Construction of Temporary Horizontal Internal Bracing for the Tower Columns:

[0021] As the tower height increases, a temporary steel pipe brace is installed on the tower to prevent the tower from tilting inward.

[0022] Step 7: Construction of the tower column closure section:

[0023] During construction, the steel bracket support consists of, from bottom to top, the steel bracket, the adjustable assembly unloading device, and the longitudinal distribution beam;

[0024] Among them, the positioning plate of the steel bracket is connected to the pre-embedded threaded steel and welded with double-jointed I-beams, and at the same time, horizontal stiffening plates and vertical stiffening plates are set.

[0025] The adjustable modular unloading device has an insertion hole at the bottom of the top seat for inserting blocks into the top of the base; the two lead screws of the adjustable modular unloading device pass through the through holes on the trapezoidal slider and reach the lead screw collection box at the top of the base. Both lead screws have a drive shaft inside, which is connected to the first gear and the second gear respectively; slide rails are symmetrically arranged on both sides of the base, and a slide groove is provided at the bottom of the trapezoidal slider to control the movement trajectory of the trapezoidal slider.

[0026] After the unloading device is assembled, the position of the trapezoidal slider is moved by manually adjusting the drive shaft at one end, while the other end is automatically adjusted by using gears to drive the drive shaft.

[0027] A jack is installed at the top of the base. The relative height of the tower column template panel is roughly adjusted by using a screw rod. Then, the relative height of the tower column template panel is precisely positioned by using the jack.

[0028] Furthermore, in step one, the tower support adopts a combined connecting crossbar, including a lower crossbar, an upper crossbar, a connecting block, a crossbar, and a vertical plate;

[0029] Vertical plates are welded between the lower and upper horizontal plates, and each plate is equipped with limiting holes;

[0030] Both ends of the crossbar are threaded, and adjacent crossbars are connected and fixed by sleeves; a fixed column is installed on the crossbar, and the column is provided with an adjustment groove. A pin is welded to one end of the connecting shaft, and a connecting block is welded to the other end and placed in the adjustment groove.

[0031] The upper part of the connecting block is connected to the telescopic rod, and the lower part is connected to the spring. The relative length of the telescopic rod is adjusted by adjusting the knob. When the telescopic rod extends, the connecting block compresses the spring, causing the connecting shaft to move downward. When the telescopic rod shortens, the spring rebounds the connecting block, causing the connecting shaft to move upward, thereby flexibly adjusting the relative position of the pin inserted into the limiting hole.

[0032] Adjust the nuts on the screws on both sides of the vertical plate to make the arc-shaped limit block press against the connecting plate on the upright, and install a rubber pad between the screw and the arc-shaped limit block.

[0033] Furthermore, in step three, the joints of the reinforcing bars are staggered during installation, and the area of ​​the joints of the reinforcing bars in the same cross section does not exceed 50%.

[0034] Furthermore, in step six, an adjustable temporary support frame is used for internal support. One end of the steel pipe support is placed on the U-shaped plate of the first limiting device of the adjustable temporary support frame and fixed with bolts. The back of the positioning plate on the first limiting device is welded with embedded threaded steel, and the front is provided with a U-shaped plate. Several triangular connecting plates are welded to strengthen the connection of the device. A cover plate is installed at the end of the U-shaped plate and flipped through a rotating shaft.

[0035] A conical block is welded to the other end of the steel pipe support. The conical block is connected to the middle block, and a second slider is set on both sides. The second slider is placed in the second limiting device.

[0036] The positioning plate of the second limiting device has a pre-embedded threaded steel welded to its back and a second limiting track on its front. The relative position of the steel pipe support at this end is adjusted by the second slider, and the steel pipe support is fixed by bolts passing through the through holes on the second limiting track and the second slider in sequence.

[0037] Connecting rods are evenly distributed between adjacent steel pipe supports. The first slider is welded to both ends of the connecting rod and placed in the first limit track. The relative position between the connecting rods is adjusted according to the construction requirements, and diagonal bracing is also set.

[0038] The curved variable cross-section concrete tower column of the low-tower cable-stayed bridge is obtained through the above-mentioned construction of the curved variable cross-section concrete tower column of the low-tower cable-stayed bridge.

[0039] Compared with the prior art, the present invention has the following characteristics and beneficial effects:

[0040] 1. This invention features a modular connecting crossbar tower support system. The upper and lower positions of the pins can be flexibly adjusted using a knob, and the arc-shaped limiting block can be adjusted and tightened against the connecting plate using a screw. The length of the crossbar is flexibly adjustable using a sleeve, ensuring the stability of the tower support system and reducing construction risks.

[0041] 2. The present invention features an adjustable temporary support frame. One end of the steel pipe support is fixed, while the other end is flexibly adjusted using a slider. This makes operation convenient and improves construction efficiency.

[0042] 3. The present invention adopts an adjustable modular unloading device. By simply rotating one end of the drive shaft, the other end is driven to rotate by the gear, so that the relative unloading heights of the two ends of the unloading device are consistent, thus improving the construction quality.

[0043] 4. This invention adopts a rapid connection technology for rigid skeleton segments, and sets up end, middle and bottom positioning devices to accurately position the threaded rod, thereby improving the construction speed of rigid skeleton docking. Attached Figure Description

[0044] Figure 1 This is a plan view of the curved variable cross-section concrete tower column of a low-tower cable-stayed bridge;

[0045] Figure 2 This is a plan view of the construction of the tower column closure section;

[0046] Figure 3 This is a schematic diagram of the structure of the combined connecting crossbar;

[0047] Figure 4 This is a structural breakdown diagram of the combined connecting crossbar;

[0048] Figure 5 This is a sectional view of the combined connecting crossbar;

[0049] Figure 6 This is a structural schematic diagram of an adjustable temporary support frame;

[0050] Figure 7 This is a schematic diagram of the first limiting device;

[0051] Figure 8 This is a schematic diagram of the second limiting device;

[0052] Figure 9 This is a structural breakdown diagram of the adjustable modular unloading device;

[0053] Figure 10 This is a schematic diagram of the lead screw collection box;

[0054] Figure 11 This is a schematic diagram of the adjustable modular unloading device;

[0055] Figure 12 This is a schematic diagram of a structure for rapid connection of stiffness skeleton segments;

[0056] Figure 13 This is a schematic diagram of the bottom positioning device;

[0057] Figure 14 This is a schematic diagram of the end positioning device;

[0058] Figure 15 This is a schematic diagram of the central positioning device.

[0059] In the diagram: 1. Bridge deck; 2. Tower support; 3. Stiffened frame; 4. First limiting device; 5. Embedded threaded steel; 6. Transverse stiffening plate; 7. Longitudinal distribution beam; 8. Double-jointed I-beam; 9. Tower formwork panel; 10. Secondary back rib of tower formwork; 11. Main back rib of tower formwork; 12. Vertical stiffening plate; 13. Unloading device; 14. Positioning plate; 15. Steel pipe bracing; 16. Second limiting device; 7. Diagonal brace; 18. Concrete tower column; 19. Combined connecting crossbar; 20. Limiting hole; 21. Lower horizontal plate; 22. Upper horizontal plate; 23. Pin; 24. Connecting shaft; 25. Knob; 26. Connecting block; 27. Horizontal bar; 28. Vertical plate; 29. ​​Screw rod; 30. Fixed column; 31. Sleeve; 32. Adjusting groove; 33. Rubber pad; 34. Arc-shaped limiting block; 35. Telescopic rod 36. Connecting plate; 37. Upright pole; 38. Spring; 39. U-shaped plate; 40. Triangular connecting plate; 41. Rotating shaft; 42. Cover plate; 43. Through hole; 44. Connecting rod; 45. First limiting track; 46. First slider; 47. Second limiting track; 48. Second slider; 49. Intermediate block; 50. Conical block; 51. Insert block; 52. Lead screw collection box; 53. Base; 54. Jack; 55. Slide rail; 56. Slide groove; 57. Trapezoidal slider; 58. Insertion hole; 59. Top seat; 60. Drive shaft; 61. Lead screw; 62. First gear; 63. Second gear; 64. Bottom positioning device; 65. Positioning threaded rod; 66. Middle positioning device; 67. End positioning device; 68. Connecting column; 69. L-shaped positioning plate; 70. Limiting terminal; 71. Reserved limiting groove. Detailed Implementation

[0060] The present invention will be further described below with reference to embodiments, wherein traditional construction methods such as welding and installation will not be described in detail. The following description of the embodiments is only for the purpose of helping to understand the present invention. It should be noted that for those skilled in the art, several improvements and modifications can be made to the present invention without departing from the principle of the present invention, and these improvements and modifications also fall within the protection scope of the claims of the present invention.

[0061] Those skilled in the art should understand that, in the disclosure of this application, the terms "longitudinal," "lateral," "upper," "lower," "front," "rear," "left," "right," "vertical," "horizontal," "top," "bottom," "inner," and "outer," etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are only for the convenience of describing this application and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, the above terms should not be construed as limitations on this application.

[0062] Figure 1 This is a plan view of the curved variable cross-section concrete tower column of a low-tower cable-stayed bridge; Figure 2 This is a plan view of the construction of the tower column closure section; Figure 3 This is a schematic diagram of the structure of the combined connecting crossbar; Figure 4 This is a structural breakdown diagram of the combined connecting crossbar; Figure 5 This is a sectional view of the combined connecting crossbar; Figure 6 This is a structural schematic diagram of an adjustable temporary support frame; Figure 7 This is a schematic diagram of the first limiting device; Figure 8 This is a schematic diagram of the second limiting device; Figure 9 This is a structural breakdown diagram of the adjustable modular unloading device; Figure 10 This is a schematic diagram of the lead screw collection box; Figure 11 This is a schematic diagram of the adjustable modular unloading device; Figure 12 This is a schematic diagram of a structure for rapid connection of stiffness skeleton segments; Figure 13 This is a schematic diagram of the bottom positioning device; Figure 14 This is a schematic diagram of the end positioning device; Figure 15 This is a schematic diagram of the central positioning device.

[0063] Example 1

[0064] Referring to the figures, the construction structure of the curved variable cross-section concrete tower column of the low-tower cable-stayed bridge includes a combined connecting crossbar adjustable temporary support frame; an adjustable assembly unloading device; and a rapid connection technology for stiffened frame segments.

[0065] The combined connecting crossbar consists of: a vertical plate 28 welded between the lower crossbar 21 and the upper crossbar 22, both of which are provided with limiting holes 20; both ends of the crossbar 27 are threaded, and adjacent crossbars 27 are connected and fixed by sleeves 31; a fixed column 30 is installed on the crossbar 27, and the column is provided with an adjusting groove 32; a pin 23 is welded to one end of the connecting shaft 24, and a connecting block 26 is welded to the other end and placed in the adjusting groove 32; the upper part of the connecting block 26 is connected to the telescopic rod 35, and the lower part is connected to the spring 38, and the relative length of the telescopic rod 35 is adjusted by adjusting the knob 25; when extended... When the telescopic rod 35 extends, the connecting block 26 compresses the spring 38, causing the connecting shaft 24 to move downwards; when the telescopic rod 35 shortens, the spring 38 rebounds the connecting block 26, causing the connecting shaft 24 to move upwards, thereby flexibly adjusting the relative position of the pin 23 inserted into the limiting hole 20; in addition, by adjusting the nuts on the screw 29 on both sides of the vertical plate 28, the arc-shaped limiting block 34 is pressed against the connecting plate 36 on the upright 37, and a rubber pad 33 is installed between the screw 29 and the arc-shaped limiting block 34 to reduce frictional resistance and ensure the overall stability of the support structure.

[0066] The adjustable temporary support frame consists of: one end of the steel pipe support 15 is placed on the U-shaped plate 39 of the first limiting device 4 and fixed with bolts; the positioning plate 14 on the first limiting device 4 has a pre-embedded threaded steel 5 welded to its back, and a U-shaped plate 39 is provided on its front, with several triangular connecting plates 40 welded to reinforce the connection of the device; a cover plate 42 is installed at the end of the U-shaped plate 39, which is connected to the rotating shaft 41 for easy positioning and fixing; a conical block 50 is welded to the other end of the steel pipe support 15, the conical block 50 is connected to the middle block 49, and a second slider 48 is provided on both sides, which is used to position the support. Within the second limiting device 16; the back of the positioning plate 14 on the second limiting device 16 is also welded with pre-embedded threaded steel 5, and the front is provided with a second limiting track 47. The relative position of the steel pipe support 15 at this end is adjusted by the second slider 48, and the steel pipe support 15 is fixed by bolts passing through the through holes on the second limiting track 47 and the second slider 48 in sequence; connecting rods 44 are evenly distributed between adjacent steel pipe supports 15, and the two ends of the connecting rods 44 are welded with first sliders 46 and placed in the first limiting track 45. The relative position between the connecting rods 44 can be flexibly adjusted according to the construction requirements.

[0067] The adjustable assembly-type unloading device consists of: a top seat 59 with an insert block 51 at its bottom that inserts into the insertion hole 58 at the top of the base 53; two lead screws 61 passing through the through holes 43 on the trapezoidal slider 57 and reaching the lead screw collection box 52 at the top of the base 53; each lead screw 61 has a drive shaft 60 inside, which is connected to the first gear 62 and the second gear 63 respectively; symmetrical slide rails 55 are provided on both sides of the base 53, and a slide groove 56 is provided at the bottom of the trapezoidal slider 57 to control the movement trajectory of the trapezoidal slider 57; after the unloading device is assembled, the position of the trapezoidal slider 57 can be moved by manually adjusting the drive shaft 60 at one end, while the other end is automatically adjusted by the gear driving the drive shaft 60, eliminating the need for manual adjustment at both ends and solving the problem of different operating precision when adjusting at both ends; in addition, a jack 54 is provided at the top of the base 53, which can be used to coarsely adjust the relative height of the top seat 59 during construction by using the lead screws 61, and then precisely position the relative height of the top seat 59 by using the jack 54, thus improving the accuracy of construction.

[0068] The rapid connection technology for stiffened frame segments is as follows: the stiffened frame 3 is connected segment by segment as the tower column concrete segments rise; during connection, a bottom positioning device 64 is set on the upper part of the previous stiffened frame segment 3, an end positioning device 67 is set on the upper part of the subsequent stiffened frame segment 3, and a middle positioning device 66 is set on the bottom; the positioning threaded rod 65 passes through the middle positioning device 66, and both ends are equipped with connecting columns 68, which are connected and fixed to the sleeves 31 on each positioning device by threads and bolts; among them, the L-shaped positioning plates 69 of the bottom positioning device 64, the middle positioning device 66 and the end positioning device 67 are equipped with limit terminals 70, which are placed in the reserved limit grooves 71 of the stiffened frame 3 to facilitate the positioning and installation of the device and improve construction efficiency.

[0069] Example 2

[0070] The construction method and steps for the curved variable cross-section concrete tower columns of this low-tower cable-stayed bridge are as follows:

[0071] Step 1: Arrangement of Tower Support 2:

[0072] As the tower construction progresses, the tower support 2 is erected in a timely manner; the tower support is placed on the already poured bridge deck 1, and according to the construction requirements, a certain area below the center of the tower is the reinforcement zone for poles 37.

[0073] Among them, the tower column support 2 adopts the combined connecting crossbar of Embodiment 1.

[0074] Step 2, Construction of the rigid frame 3:

[0075] The rigid frame 3 is laid out and manufactured at a 1:1 scale to form a horizontal tripod; the rapid connection technology of the rigid frame segments in Example 1 is used for construction.

[0076] Step 3: Tower column reinforcement binding:

[0077] When tying reinforcing bars, a tower crane is used to hoist each bundle onto the tower column using specialized lifting equipment. During installation, care must be taken to stagger the joints, and the area of ​​joints in the same cross-section of the reinforcing bars should not exceed 50%.

[0078] Step 4: Tower Column Formwork Engineering:

[0079] Because the bridge tower column has a variable cross-section and a small cross-sectional size, the tower column formwork panel 9 is made of Vesa board, the tower column formwork secondary back rib 10 is made of wooden beams, and the tower column formwork main back rib 11 is made of steel beams. The formwork system is tightened by the tower column support and diagonal bracing is set to support the tower column support 2.

[0080] Step 5: Concrete construction of the tower column:

[0081] The concrete is delivered using a truck pumping process, with flexible hoses for placement and a duct for placement. The laboratory strictly controls the concrete mix ratio and slump during production. After the concrete is poured, it is promptly watered for curing.

[0082] Step Six: Construction of Temporary Horizontal Internal Bracing for the Tower Columns:

[0083] As the tower height increases, a temporary steel pipe brace 15 needs to be installed on the tower to prevent the tower from tilting inward; the adjustable temporary brace frame of Example 1 allows for flexible construction of the horizontal internal bracing.

[0084] Step 7: Construction of the tower column closure section:

[0085] During the construction of the tower column closure section, the support structure from bottom to top consists of steel brackets, adjustable assembly unloading device 13, and longitudinal distribution beam 7.

[0086] The positioning plate 14 of the steel bracket is connected to the pre-embedded threaded steel 5 and welded with double-jointed I-beams 8. At the same time, horizontal stiffening plates 6 and vertical stiffening plates 12 are set to ensure the stability of the bracket structure connection. The adjustable assembly type unloading device 13 has a bottom of the top seat 59 with an insert block 51 that inserts into the insertion hole 58 at the top of the base 53. The two end screw rods 61 pass through the through holes 43 on the trapezoidal slider 57 and reach the screw rod collection box 52 at the top of the base 53. Both screw rods 61 are equipped with a drive shaft 60, which is connected to the first gear 62 and the second gear 63 respectively. The base 53 is symmetrically provided with slide rails 55 on both sides. The bottom of the trapezoidal slider 57 is provided with a slide groove 56 to control the movement trajectory of the trapezoidal slider 57.

[0087] After the unloading device is assembled, the position of the trapezoidal slider 57 can be moved by manually adjusting the drive shaft 60 at one end, while the other end can be automatically adjusted by using gears to drive the drive shaft 60. This eliminates the need for manual adjustment at both ends, solving the problem of different operating precision that may occur when adjusting at both ends. In addition, a jack 54 is provided on the top of the base 53. During construction, the relative height of the tower column template panel 9 can be roughly adjusted by using the screw rod 61, and then the relative height of the tower column template panel 9 can be precisely positioned by using the jack 54, thus improving the construction accuracy.

[0088] The parts not described in detail in this application are prior art, and therefore are not described in detail in this application.

[0089] It is understood that the term "a" should be understood as "at least one" or "one or more", that is, in one embodiment, the number of an element can be one, while in another embodiment, the number of the element can be multiple, and the term "a" should not be understood as a limitation on the number.

[0090] Although this document uses a significant amount of technical terminology, the possibility of using other terms is not excluded. These terms are used merely to facilitate the description and explanation of the nature of this application; interpreting them as any additional limitation would be contrary to the spirit of this application.

[0091] This application is not limited to the above-described preferred embodiments. Anyone can derive other products in various forms under the guidance of this application. However, regardless of any changes made to their shape or structure, any technical solution that is the same as or similar to that of this application falls within the protection scope of this application.

Claims

1. A construction method of a curved variable cross-section concrete tower column of a low tower cable-stayed bridge, characterized by, Includes the following steps: Step 1, Tower Support (2) Layout: As the tower construction progresses, the tower support (2) is erected in a timely manner; the tower support (2) is placed on the already poured bridge deck (1), and according to the construction requirements, a certain area below the center of the tower is the reinforcement zone for the uprights (37); Step 2, Construction of the rigid frame (3): The rigid frame (3) is laid out and made at a 1:1 scale to form a horizontal tripod; the rigid frame (3) is joined up section by section as the concrete segments of the tower column rise; During docking, a bottom positioning device (64) is set on the upper part of the front stiffening frame (3), an end positioning device (67) is set on the upper part of the rear stiffening frame (3), and a middle positioning device (66) is set on the bottom. The positioning threaded rod (65) passes through the central positioning device (66), and both ends are provided with connecting posts (68). It is connected and fixed to the sleeve (31) on each positioning device by threads and bolts. Among them, the bottom positioning device (64), the middle positioning device (66) and the end positioning device (67) are equipped with limit terminals (70) on the L-shaped positioning plates (69) and placed in the reserved limit groove (71) of the rigid frame (3); Step 3: Tower column reinforcement binding: During the binding of steel bars, a tower crane is used to hoist each bundle onto the tower column using specialized lifting equipment. Step 4: Tower Column Formwork Engineering: The tower column formwork panel (9) is made of Vesa board, the secondary back rib (10) of the tower column formwork is made of wooden beams, and the main back rib (11) of the tower column formwork is made of steel beams. The formwork system is tightened by the tower column support and diagonal bracing is set on the tower column support (2). Step 5: Concrete construction of the tower column: The concrete is delivered using a truck pump, and water is sprayed for curing immediately after the concrete is poured. Step Six: Construction of Temporary Horizontal Internal Bracing for the Tower Columns: As the tower height increases, a temporary steel pipe brace (15) is installed on the tower to prevent the tower from tilting inward; Step 7: Construction of the tower column closure section: During construction, the steel bracket support consists of, from bottom to top, the steel bracket, the adjustable assembly unloading device (13), and the longitudinal distribution beam (7); Among them, the positioning plate (14) of the steel bracket is connected to the pre-embedded threaded steel (5) and welded with double-jointed I-beams (8), and at the same time, horizontal stiffening plates (6) and vertical stiffening plates (12) are set. The adjustable modular unloading device (13) has a bottom of the top seat (59) with a plug (51) inserted into the insertion hole (58) at the top of the base (53); the two ends of the adjustable modular unloading device (13) have screws (61) passing through the through hole (43) on the trapezoidal slider (57) and reaching the screw collection box (52) at the top of the base (53); both screws (61) have a drive shaft (60) inside, which is connected to the first gear (62) and the second gear (63) respectively; the base (53) has symmetrical slide rails (55) on both sides, and the bottom of the trapezoidal slider (57) has a groove (56) to control the movement trajectory of the trapezoidal slider (57); After the unloading device is assembled, manually adjust the position of the trapezoidal slider (57) by adjusting the drive shaft (60) at one end, and automatically adjust the other end by using gears to drive the drive shaft (60). A jack (54) is set on the top of the base (53). The relative height of the tower column template panel (9) is roughly adjusted by the screw rod (61), and then the relative height of the tower column template panel (9) is precisely positioned by the jack (54).

2. The construction method of a curved variable cross-section concrete tower column of a low tower cable-stayed bridge according to claim 1, characterized in that, In step one, the tower support (2) adopts a combined connecting crossbar including a lower crossbar (21), an upper crossbar (22), a connecting block (26), a crossbar (27), and a vertical plate (28); A vertical plate (28) is welded between the lower horizontal plate (21) and the upper horizontal plate (22), and both are provided with limiting holes (20); Both ends of the crossbar (27) are threaded, and adjacent crossbars (27) are connected and fixed by sleeves (31); a fixed column (30) is installed on the crossbar (27), and an adjustment groove (32) is provided on the column (30); a pin (23) is welded to one end of the connecting shaft (24), and a connecting block (26) is welded to the other end and placed in the adjustment groove (32); The upper part of the connecting block (26) is connected to the telescopic rod (35), and the lower part is connected to the spring (38). The relative length of the telescopic rod (35) can be adjusted by adjusting the knob (25). When the length of the telescopic rod (35) is extended, the connecting block (26) compresses the spring (38), causing the connecting shaft (24) to move downward. When the length of the telescopic rod (35) is shortened, the spring (38) rebounds the connecting block (26), causing the connecting shaft (24) to move upward, thereby flexibly adjusting the relative position of the pin (23) inserted into the limiting hole (20). By adjusting the nuts on the screw rods (29) on both sides of the vertical plate (28), the arc-shaped limiting block (34) is pressed against the connecting plate (36) on the upright (37), and a rubber pad (33) is installed between the screw rod (29) and the arc-shaped limiting block (34).

3. The construction method of a curved variable cross-section concrete tower column of a low tower cable-stayed bridge according to claim 1, characterized in that, In step three, the joints of the reinforcing bars are staggered during installation, and the area of ​​the joints of the reinforcing bars in the same cross section does not exceed 50%.

4. The construction method for curved variable cross-section concrete tower columns of a low-tower cable-stayed bridge as described in any one of claims 1-3, characterized in that, In step six, the steel pipe bracing (15) is internally supported by an adjustable temporary bracing frame. One end of the steel pipe bracing (15) is placed on the U-shaped plate (39) of the first limiting device (4) of the adjustable temporary bracing frame and fixed with bolts. The positioning plate (14) on the first limiting device (4) has a pre-embedded threaded steel (5) welded to its back and a U-shaped plate (39) on its front. Several triangular connecting plates (40) are welded to reinforce the connection of the device. The end of the U-shaped plate (39) is fitted with a cover plate (42) and is connected to flip through a rotating shaft (41). The steel pipe brace (15) has a conical block (50) welded to the other end. The conical block (50) is connected to the middle block (49), and a second slider (48) is provided on both sides. The second slider (48) is placed in the second limiting device (16). The positioning plate (14) on the second limiting device (16) has a pre-embedded threaded steel (5) welded on the back and a second limiting track (47) on the front. The relative position of the steel pipe support (15) at this end is adjusted by the second slider (48), and the steel pipe support (15) is fixed by bolts passing through the through holes on the second limiting track (47) and the second slider (48) in sequence. Connecting rods (44) are evenly distributed between adjacent steel pipe supports (15). First sliders (46) are welded to both ends of the connecting rods (44) and placed in the first limiting track (45). The relative positions between the connecting rods (44) are adjusted according to the construction requirements, and diagonal bracing (17) is set at the same time.

5. A curved variable cross-section concrete tower column for a low-tower cable-stayed bridge, characterized in that: The structure is obtained by constructing the curved variable cross-section concrete tower column of the low-tower cable-stayed bridge as described in any one of claims 1-4.

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