Method for accurately positioning embedded steel anchor box on space cable surface of steel box girder

Abstract

The invention relates to a method for accurately positioning an embedded steel anchor box on a steel box girder space cable plane. The method comprises the following steps: carrying out three-dimensional modeling on a steel anchor box in a full bridge range, and arranging a universal dummy shaft in a three-dimensional model; a bearing plate, a bearing plate and an anchor bearing plate of the steel anchor box are blanked through numerical control cutting equipment, grooves are formed after blanking is completed, and anchoring units are assembled and formed; the anchoring units, the tuyere bottom plate and the tuyere side plates are fixed through fixing devices, and each tuyere block body is provided with a plurality of fixing devices so as to limit the spatial position state of the anchoring units in the tuyere block body; fine adjustment is conducted on the anchoring unit on the fixing device, and welding of the anchoring unit and the tuyere block body and welding of the tuyere block body and the steel box girder box body are conducted; and the formed steel box girder is subjected to overall trial assembly, and the overall line shape of bridge position installation of the steel box girder and the installation precision of the steel anchor box are verified. The precision of the steel anchor box is ensured while the construction line shape of the steel box girder is ensured.

Description

Technical Field

[0001] This invention relates to the field of steel bridge anchor box manufacturing technology, and in particular to a method for precise positioning of a steel anchor box embedded in the spatial cable surface of a steel box girder. Background Technology

[0002] The spatial cable elliptical tower self-anchored suspension bridge is a structural system composed of a split steel box girder, elliptical towers, and cables, and is one of the most complex structural forms among various bridge types. Construction control of the embedded anchorage structure within the spatial cable plane of the substructure steel box girder is a key aspect in ensuring the internal force and alignment quality of the completed bridge. While the conventional method for anchoring the cable-stayed beam is to use external lugs for ease of measurement and positioning, embedded anchorage structures have become widely adopted in large-span suspension bridges in recent years.

[0003] The anchoring unit is a fully welded anchoring structure in the form of a pressure-bearing steel anchor box, installed inside the air nozzle of the steel box girder. The steel anchor box is welded to both sides of the air nozzle anchoring diaphragm. The anchoring unit mainly consists of anchoring diaphragms, anchor plates, pressure plates, and load-bearing plates. After the anchoring unit is manufactured, it participates in the assembly of the air nozzle block together with the top, bottom, sides, and diaphragms of the air nozzle. At this time, the anchoring unit is only used for positioning and is not welded to the air nozzle block. After the air nozzle block is manufactured, it participates in the overall pre-assembly of the split steel box girder.

[0004] This structural form has advantages such as high strength, high rigidity, and good force transmission; at the same time, the anchor box is placed inside the box, avoiding the problem of corrosion that is easily caused by traditional anchor boxes being exposed to humid air for a long time.

[0005] The anchorage unit, as the cable-stayed anchorage structure, is set within the steel box girder and is a crucial force transmission and connection structure. During construction, the diagonal tension of the cables is primarily borne by the steel anchor box, making it a key core component of the steel box girder with high installation precision requirements. Furthermore, due to the diverse on-site installation methods for girder segments, including side-span jacking, in-situ hoisting of the lower tower section, and mid-span cantilever hoisting, coupled with harsh construction conditions, numerous factors affect installation precision. How to precisely control the installation position of the steel anchor box during the steel girder manufacturing process is a pressing problem that needs to be solved. Therefore, it is necessary to propose methods for controlling the installation angle and alignment of the steel anchor box to address this issue. Summary of the Invention

[0006] Therefore, the present invention provides a method for precise positioning of steel anchor boxes embedded in the spatial cable surface of steel box girders. This method enables precise control of the positioning accuracy of the steel anchor boxes during the overall fabrication of steel box girder segments in the steel beam manufacturing process. It also enables precise positioning of the steel anchor boxes in three-dimensional space during installation, ensuring both the construction alignment of the steel box girder and the accuracy of the steel anchor boxes.

[0007] To solve the above-mentioned technical problems, the present invention provides a method for precise positioning of a steel anchor box embedded in a spatial cable surface of a steel box girder, comprising: S1. Based on the manufacturing alignment of the steel box girder and parameters including the anchor box angle and the theoretical coordinates of the anchor points, a three-dimensional model of the steel anchor boxes within the entire bridge is created. A general dummy axis is arranged in the three-dimensional model, and the theoretical anchor points located inside the steel box girder are transformed and led out to the outside of the box through the dummy axis. The transformed theoretical coordinates of the anchor points are obtained on the dummy axis outside the box. The CNC precision cutting data of the anchor unit parts and the two-dimensional construction drawings of the anchor unit and the vent block are exported from the three-dimensional model as the basis for subsequent assembly and positioning. S2. Using CNC cutting equipment, the load-bearing plate, pressure plate, and anchor plate of the steel anchor box are cut and beveled. The structural assembly position lines of the load-bearing plate, pressure plate, and anchor plate are marked on the marking platform. The load-bearing plate and pressure plate are assembled and welded together according to the lines, and then the load-bearing surface is machined together with the anchor plate and the anchor holes are bored. The assembly position lines of the pressure plate and load-bearing plate and the anchor point projection are marked on the anchoring partition. The pressure plate and load-bearing plate welded parts and the anchor plate are assembled and welded according to the lines to form the anchoring unit. S3. The top plate, bottom plate, side plate, and partition of the nozzle are respectively made into plate units. The assembly position lines of the anchoring unit are engraved on the top plate, bottom plate, and side plate of the nozzle. While welding the nozzle blocks according to the process sequence, the positioning anchoring units are assembled according to the lines. After the anchoring unit is positioned, the anchoring unit is fixed to the bottom plate and side plate of the nozzle by the fixing device. Several fixing devices are set for each nozzle block to restrict the spatial position of the anchoring unit in the nozzle block. S4. In the assembly stage of the split steel box girder, the vent block is assembled with the steel box girder box body. Before welding the anchoring unit to the vent block, the actual spatial coordinates of the anchor points on the false axis outside the box are measured using a total station and compared with the theoretical coordinates of the anchor points on the false axis. The anchoring unit is finely adjusted by the fixing device so that the deviation between the measured anchor point coordinates and the theoretical anchor point coordinates meets the allowable value of the specification. Then, the welding of the anchoring unit to the vent block and the welding of the vent block to the steel box girder box body are carried out in sequence. S5. Perform an overall trial assembly of the formed steel box girder. Measure the spatial coordinates of all pseudo-axis anchor points of the assembled segment using a total station. Based on the coordinate data, calculate the lateral distance L between the steel anchor boxes of the left and right steel box girders, the longitudinal distance a between the steel anchor boxes of adjacent beam segments, and the longitudinal misalignment distance b between the left and right anchor boxes of the same segment. Compare the measured distances with the corresponding theoretical distances in the three-dimensional model to verify the overall alignment of the steel box girder bridge site installation and the installation accuracy of the steel anchor boxes.

[0008] In one embodiment of the present invention, in step S1, the dummy shaft is a circular rod, and a measuring point reflective sticker is pasted at the center of the end of the dummy shaft for automatic tracking measurement by the total station.

[0009] In one embodiment of the present invention, in step S2, the load-bearing plate, pressure plate, and anchor plate of the steel anchor box are cut using a CNC laser cutting machine.

[0010] In one embodiment of the present invention, in step S3, each nozzle block is provided with four sets of the fixing devices, which are respectively arranged on the nozzle bottom plate and nozzle side plate on both sides of the anchoring unit to limit the displacement and rotation of the anchoring unit relative to the nozzle block.

[0011] In one embodiment of the present invention, the fixing device includes a fixing device base, an adjusting angle steel, a screw support frame, an angle steel fixing bolt, a first fixing screw, and a second fixing screw; The fixing device base is used to fix it to the plate rib of the nozzle bottom plate or the nozzle side plate, and the screw support frame is set on the fixing device base; The two adjusting angle steels are connected to the base of the fixing device by the angle steel fixing bolts. The base of the fixing device is provided with an adjusting groove suitable for adjusting the position of the angle steel fixing bolts. The distance between the two adjusting angle steels is adjusted by the angle steel fixing bolts so as to be embedded between two adjacent ribs of the nozzle bottom plate or the nozzle side plate. The outer wall surface of the adjusting angle steel is suitable for being in close contact with the outer surface of the ribs of the nozzle bottom plate or the nozzle side plate. The base of the fixing device extends with support plates facing the outer wall surfaces of the two adjusting angle steels respectively; Each of the support plates is threadedly connected to the first fixing screw, which can abut against the inner side of the nozzle base plate or the nozzle side plate rib. The second fixing screw is threadedly connected to the screw support frame and can abut against the anchoring plate of the anchoring unit; Both the first fixing screw and the second fixing screw are fitted with locking nuts; The axis of the first fixing screw is parallel to the plane of the nozzle base plate or the nozzle side plate, and the axis of the second fixing screw is perpendicular to the plane of the anchor plate.

[0012] In one embodiment of the present invention, the screw support frame is provided in two sets, and each support plate is provided with two first fixing screws.

[0013] In one embodiment of the present invention, step S3, which involves fixing the anchoring unit to the nozzle base plate and the nozzle side plate using a fixing device, includes: Loosen the angle steel fixing bolts on the fixing device, adjust the adjusting angle steel so that the gap between the two adjusting angle steels can be embedded between the two adjacent plate ribs on the bottom plate or side plate of the air nozzle, and make the outer wall of the adjusting angle steel fit tightly against the outer side of the corresponding plate rib. Then tighten the angle steel fixing bolts. Adjust the first fixing screws on both sides so that the first fixing screws are pressed against the outer side of the corresponding plate rib; Adjust the second fixing screw at the top to make it press against the anchoring plate of the anchoring unit.

[0014] In one embodiment of the present invention, step S4, which involves fine-tuning the anchoring unit via the fixing device, includes: Based on the coordinate deviation value, determine the direction and amount of adjustment required for the anchoring unit. By rotating the second fixing screw on the fixing device, change the spatial position of the anchoring unit within the air nozzle block until the deviation between the measured coordinates and the theoretical coordinates of each dummy axis anchor point meets the allowable range specified in the standard.

[0015] The technical solution of the present invention has the following advantages compared with the prior art: This invention discloses a method for precise positioning of steel anchor boxes embedded in the spatial cable plane of steel box girders. Through precise control of the installation angle and alignment of the steel anchor boxes throughout the entire process of steel box girder unit fabrication, block fabrication, and overall assembly, the installation accuracy of the anchor boxes is improved. This avoids the traditional method of measuring within the narrow space of the box girder and manually adjusting the anchoring structure based on experience, reducing operational difficulty, minimizing human error, improving manufacturing efficiency, and making the steel anchor box installation process more standardized, modular, and repeatable.

[0016] This invention extends the anchor points inside the steel box girder to the outside of the girder via dummy axes, and calculates the converted anchor point coordinates using a 3D model. A total station can then be used to quickly measure the converted anchor point coordinates outside the box girder, allowing for the determination of the anchor box installation accuracy. This solves the problem of the inability to measure anchor points inside the box girder, and is simple and easy to implement. Attached Figure Description

[0017] To make the content of this invention easier to understand, the invention will be further described in detail below with reference to specific embodiments and accompanying drawings.

[0018] Figure 1 This is a schematic diagram of the anchoring unit according to an embodiment of the present invention.

[0019] Figure 2 This is a schematic diagram of the nozzle block according to an embodiment of the present invention.

[0020] Figure 3 This is a schematic diagram of a split steel box girder according to an embodiment of the present invention.

[0021] Figure 4 This is a schematic diagram of the pseudo-axis according to an embodiment of the present invention.

[0022] Figure 5 This is a right-view schematic diagram of a dummy axis according to an embodiment of the present invention.

[0023] Figure 6 This is a schematic diagram of the fixing device according to an embodiment of the present invention.

[0024] Figure 7 This is a side view of the mounting device according to an embodiment of the present invention.

[0025] Figure 8 This is a front view of the fixing device installed according to an embodiment of the present invention.

[0026] Figure 9 An oblique 45° view of the fixing device in an embodiment of the present invention.

[0027] Figure 10 yes Figure 9 A magnified view of a portion of the image.

[0028] Figure 11 This is a schematic diagram of the overall anchor point control item in an embodiment of the present invention.

[0029] Figure 12 for Figure 11 View along the AA direction.

[0030] Explanation of reference numerals on the accompanying drawings: 1. Anchoring unit; 11. Anchoring diaphragm; 12. Bearing plate; 13. Anchor pad; 14. Embedded stiffener; 15. Load-bearing plate; 2. Nozzle block; 21. Nozzle top plate; 22. Nozzle bottom plate; 23. Nozzle partition; 24. Nozzle side plate; 25. Rib; 3. Split-type steel box girder; 31. Single-span steel box girder; 32. Crossbeam block; 33. Embedded anchoring unit; 4. Fixing device; 41. Fixing device base; 42. Adjusting angle steel; 43. Screw support frame; 44. Angle steel fixing bolt; 45. First fixing screw; 46. Second fixing screw; 47. Support plate; 48. Adjusting groove; 49. Locking nut; 5. False shaft. Detailed Implementation

[0031] The present invention will be further described below with reference to the accompanying drawings and specific embodiments, so that those skilled in the art can better understand and implement the present invention. However, the embodiments described are not intended to limit the present invention.

[0032] In this invention, when directions (up, down, left, right, front, and back) are described, it is only for the convenience of describing the technical solution of this invention, and does not indicate or imply that the technical features referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, it should not be construed as a limitation of this invention.

[0033] In this invention, "several" means one or more, "multiple" means two or more, "greater than," "less than," "exceeding," etc., are understood to exclude the stated number; "above," "below," "within," etc., are understood to include the stated number. In the description of this invention, the terms "first" and "second" are used only to distinguish technical features and should not be construed as indicating or implying relative importance, or implicitly indicating the number of indicated technical features, or implicitly indicating the order of the indicated technical features.

[0034] In this invention, unless otherwise explicitly defined, the terms "setting," "installing," and "connecting" should be interpreted broadly. For example, they can refer to a direct connection or an indirect connection through an intermediate medium; a fixed connection, a detachable connection, or an integrally formed connection; a mechanical connection, an electrical connection, or a connection capable of mutual communication; or the internal connection of two components or the interaction between two components. Those skilled in the art can reasonably determine the specific meaning of the above terms in this invention based on the specific content of the technical solution.

[0035] The present invention provides a method for precise positioning of a steel anchor box embedded in a spatial cable surface of a steel box girder, comprising: S1. Based on the manufacturing alignment of the steel box girder and parameters including anchor box angles and theoretical coordinates of anchor points, a three-dimensional model of the steel anchor boxes throughout the entire bridge is created. A general pseudo-axis 5 is then arranged in the three-dimensional model, referencing... Figure 4 , reference Figure 11 As shown, the theoretical anchor points located inside the steel box girder are transformed and led out to the outside of the box girder through the dummy axis 5. The transformed theoretical coordinates of the anchor points are obtained on the dummy axis 5 outside the box girder. The CNC precision cutting data of the anchor unit 1 parts and the two-dimensional construction drawings of the anchor unit 1 and the air nozzle block 2 are exported from the three-dimensional model as the basis for subsequent assembly and positioning.

[0036] Among them, reference Figure 1 As shown, anchoring unit 1 includes a steel anchor box and an anchoring partition 11; refer to Figure 2 As shown, the steel anchor box includes a pressure plate 12, a load-bearing plate 15, an anchor plate 13, and an embedded stiffener 14; the air nozzle block 2 includes an air nozzle top plate 21, an air nozzle bottom plate 22, an air nozzle partition 23, an air nozzle side plate 24, and an anchoring unit 1; refer to Figure 3 As shown, the split steel box girder 3 includes a single steel box girder 31, a crossbeam block 32, and an embedded anchoring unit 33.

[0037] S2. Using CNC cutting equipment, the load-bearing plate 15, pressure plate 12, and anchor plate 13 of the steel anchor box are cut and beveled. The structural assembly position lines of the load-bearing plate 15, pressure plate 12, and anchor plate 13 are marked on the marking platform. The load-bearing plate 15 and pressure plate 12 are assembled and welded together according to the lines, and then the load-bearing surface and anchor holes are machined together with the anchor plate 13. The assembly position lines of the pressure plate 12 and load-bearing plate 15 and the anchor point projection are marked on the anchoring partition 11. The welded parts of the pressure plate 12 and load-bearing plate 15 and the anchor plate 13 are assembled and welded according to the lines to form the anchoring unit 1. S3. Reference Figure 9 As shown, the top plate 21, bottom plate 22, side plate 24, and partition plate 23 of the nozzle are respectively made into plate units. The assembly position lines of the anchoring unit 1 are engraved on the top plate 21, bottom plate 22, and side plate 24. While welding the nozzle block 2 according to the process sequence, the positioning anchoring unit 1 is assembled according to the lines. After the anchoring unit 1 is positioned, it is fixed to the bottom plate 22 and side plate 24 of the nozzle by the fixing device 4. Several fixing devices 4 are set in each nozzle block 2 to restrict the spatial position of the anchoring unit 1 in the nozzle block 2. Note that after the anchoring block is positioned, it is fixed by the fixing device 4 and no welding is performed. S4. In the assembly stage of the split steel box girder 3, the air nozzle block 2 is assembled with the steel box girder box body. Before welding the anchoring unit 1 and the air nozzle block 2, the actual spatial coordinates of the anchor points on the external dummy axis 5 are measured using a total station and compared with the theoretical coordinates of the anchor points on the dummy axis 5. The anchoring unit 1 is finely adjusted by the fixing device 4 so that the deviation between the measured anchor point coordinates and the theoretical anchor point coordinates meets the allowable value of the specification. Then, the welding of the anchoring unit 1 and the air nozzle block 2 and the welding of the air nozzle block 2 and the steel box girder box body are carried out in sequence. S5. Reference Figure 11 , Figure 12As shown, the formed steel box girder underwent overall trial assembly. The spatial coordinates of all 5-anchor points of the pseudo-axis in this round of assembly were measured using a total station. Based on the coordinate data, the lateral distance L between the steel anchor boxes of the left and right steel box girders, the longitudinal distance a between the steel anchor boxes of adjacent beam segments, and the longitudinal misalignment distance b between the left and right anchor boxes of the same segment were calculated. The measured distances were compared with the corresponding theoretical distances in the 3D model to verify the overall alignment of the steel box girder bridge site and the installation accuracy of the steel anchor boxes. The lateral distance between the steel anchor boxes of the left and right box girders, the longitudinal distance between the steel anchor boxes of the box girder segments, and the longitudinal misalignment distance between the left and right anchor boxes of the same segment were verified. During the overall trial assembly of the steel box girder, the installation alignment accuracy of the bridge site was further verified. Using the spatial coordinate re-measurement method during the trial assembly stage, the lateral distance between the left and right box girders, the longitudinal distance between beam segments, and the longitudinal misalignment distance between the left and right anchor boxes were calculated by measuring the coordinates of the 5-anchor points of the pseudo-axis, achieving a systematic verification of the bridge site installation alignment and anchor box installation positions. This method not only verified the installation accuracy of anchoring unit 1, but also achieved the final closed-loop control of the overall alignment of the steel box girder.

[0038] By arranging a universal pseudo-axis 5 in the 3D model, the theoretical anchor points located inside the steel box girder are extended to the outside of the box, transforming the anchor points from unmeasurable closed spaces into measurable external spatial coordinates, thus realizing the digital and external measurement and control of the spatial position of the anchorage structure. This method eliminates the problems of difficult measurement inside the box and uncontrollable errors in traditional methods, making the inspection and calibration of the installation accuracy of anchorage unit 1 more intuitive and reliable.

[0039] In one embodiment, refer to Figure 4 , Figure 5 As shown, in step S1, the dummy shaft 5 is a circular rod, and a reflective measuring point sticker is pasted at the center of the end of the dummy shaft 5 for automatic tracking measurement by the total station.

[0040] In one embodiment, in step S2, the load-bearing plate 15, pressure plate 12, and anchor plate 13 of the steel anchor box are cut using a CNC laser cutting machine.

[0041] In one embodiment, refer to Figure 8 As shown, in step S3, each nozzle block 2 is equipped with four sets of the fixing devices 4, which are respectively arranged on the nozzle bottom plate 22 and nozzle side plate 24 on both sides of the anchoring unit 1 to limit the displacement and rotation of the anchoring unit 1 relative to the nozzle block 2.

[0042] In one embodiment, refer to Figure 6 As shown, the fixing device 4 includes a fixing device base 41, an adjusting angle steel 42, a screw support frame 43, an angle steel fixing bolt 44, a first fixing screw 45, and a second fixing screw 46; The fixing device base 41 is used to fix the nozzle bottom plate 22 or the nozzle side plate 24 to the plate rib 25, and the screw support frame 43 is set on the fixing device base 41. The two adjusting angle steels 42 are connected to the fixing device base 41 by the angle steel fixing bolts 44. The fixing device base 41 is provided with adjusting grooves 48 suitable for adjusting the position of the angle steel fixing bolts 44. The distance between the two adjusting angle steels 42 is adjusted by the angle steel fixing bolts 44 so as to be embedded between two adjacent plate ribs 25 of the air nozzle bottom plate 22 or the air nozzle side plate 24. The outer wall surface of the adjusting angle steel 42 is suitable to be in close contact with the outer surface of the plate ribs 25 of the air nozzle bottom plate 22 or the air nozzle side plate 24. The base 41 of the fixing device extends with support plates 47 facing the outer wall surfaces of the two adjusting angle steels 42 respectively; Each of the support plates 47 is threadedly connected to the first fixing screw 45, and the first fixing screw 45 can abut against the inner side of the rib 25 of the nozzle bottom plate 22 or the nozzle side plate 24. The second fixing screw 46 is threaded to the screw support frame 43 and can press against the anchoring plate 11 of the anchoring unit 1; Both the first fixing screw 45 and the second fixing screw 46 are fitted with locking nuts 49; The axis of the first fixing screw 45 is parallel to the plane of the nozzle bottom plate 22 or the nozzle side plate 24, and the axis of the second fixing screw 46 is perpendicular to the plane of the anchoring plate 11.

[0043] In one embodiment, the screw support frame 43 is provided in two sets, and each of the support plates 47 is provided with two first fixing screws 45.

[0044] In one embodiment, step S3, fixing the anchoring unit 1 to the nozzle base plate 22 and the nozzle side plate 24 by the fixing device 4, includes: Loosen the angle steel fixing bolts 44 on the fixing device 4, adjust the adjusting angle steel 42 so that the gap between the two adjusting angle steels 42 can be embedded between the two adjacent plate ribs 25 on the nozzle bottom plate 22 or the nozzle side plate 24, and make the outer wall of the adjusting angle steel 42 fit tightly against the outer side of the corresponding plate rib 25, and then tighten the angle steel fixing bolts 44. Adjust the first fixing screws 45 on both sides so that the first fixing screws 45 are pressed against the outer side of the corresponding plate rib 25; Adjust the upper second fixing screw 46 so that the second fixing screw 46 presses against the anchoring partition 11 of the anchoring unit 1.

[0045] During the assembly stage of the nozzle block 2, several fixing devices 4 are set up. Through the base, adjusting angle steel 42, first fixing screw 45, second fixing screw 46, plate rib 25, and anchoring partition 11, a three-dimensional support and six-degree-of-freedom constraint are formed, so that the lateral, longitudinal, vertical, and angular posture of the anchoring unit 1 inside the nozzle block 2 are stably restricted. Compared with the traditional welding point positioning method, the positioning process of the present invention has strong controllability, high stability, and good repeatability.

[0046] In one embodiment, step S4, fine-tuning the anchoring unit 1 via the fixing device 4, includes: Based on the coordinate deviation value, determine the direction and amount of adjustment required for the anchoring unit 1. By rotating the second fixing screw 46 on the fixing device 4, change the spatial position of the anchoring unit 1 within the air nozzle block 2 until the deviation between the measured coordinates and the theoretical coordinates of each dummy shaft 5 anchor point meets the allowable range specified in the standard.

[0047] By fine-tuning the screw of the fixing device 4, the anchoring unit 1 can be slightly adjusted according to the anchor point coordinates converted by the dummy axis 5 measured by the total station before welding the nozzle block 2. This can eliminate manufacturing and assembly errors during the overall assembly stage of the steel box girder, realize the accurate verification and real-time correction of the anchoring unit 1, and greatly improve the overall positioning accuracy.

[0048] Precise control of the installation angle and alignment of the steel anchor boxes is achieved throughout the entire process of steel box girder unit fabrication, block fabrication, and overall assembly, thereby improving the installation accuracy of the anchor boxes. By extending the anchor points inside the steel box girder to the outside of the girder via a dummy axis 5, the converted anchor point coordinates are calculated using a 3D model. A total station can then be used to quickly measure the converted anchor point coordinates outside the box girder, allowing for the determination of the anchor box installation accuracy. This method solves the problem of the inability to measure anchor points inside the box girder and is simple and easy to implement.

[0049] Finally, it should be noted that the above specific embodiments are only used to illustrate the technical solutions of the present invention and not to limit it. Although the present invention has been described in detail with reference to examples, those skilled in the art should understand that modifications or equivalent substitutions can be made to the technical solutions of the present invention without departing from the spirit and scope of the technical solutions of the present invention, and all such modifications or substitutions should be covered within the scope of the claims of the present invention.

Claims

1. A method for precise positioning of a steel box girder space cable plane embedded steel anchor box, characterized in that, The method comprises the following steps: S1, according to the linear shape of the steel box girder and parameters including the anchor box angle and the anchor point theoretical coordinates, a three-dimensional model of the steel anchor box in the whole bridge range is established, a general dummy shaft (5) is arranged in the three-dimensional model, the theoretical anchor point located in the steel box girder box is converted and led out to the outside of the box through the dummy shaft (5), the converted anchor point theoretical coordinates are obtained on the dummy shaft (5) outside the box, and the numerical control precision cutting blanking data of the anchoring unit (1) part and the two-dimensional construction drawing of the anchoring unit (1) and the tuyere block body (2) are derived from the three-dimensional model, which serves as the basis for subsequent assembly positioning; S2, the load-bearing plate (15), the pressure-bearing plate (12) and the anchor pad plate (13) of the steel anchor box are cut and blanked by using a numerical control cutting equipment, and the beveling is completed, the structure assembly position lines of the load-bearing plate (15), the pressure-bearing plate (12) and the anchor pad plate (13) are marked on a marking platform, the load-bearing plate (15) and the pressure-bearing plate (12) are assembled and welded into an integrated body according to the lines, and the load-bearing surface of the anchor pad plate (13) is machined and the anchor hole is bored; the assembly position lines of the pressure-bearing plate (12) and the load-bearing plate (15) and the anchor point projection are marked on the anchor partition plate (11), the pressure-bearing plate (12) and the load-bearing plate (15) are assembled and welded according to the lines, and the anchor pad plate (13) is formed to form the anchoring unit (1); S3, the tuyere top plate (21), the tuyere bottom plate (22), the tuyere side plate (24) and the tuyere partition plate (23) are respectively made into plate units, the assembly position lines of the anchoring unit (1) are marked on the tuyere top plate (21), the tuyere bottom plate (22) and the tuyere side plate (24), the tuyere block body (2) is assembled and welded according to the process sequence, the anchoring unit (1) is assembled and positioned according to the lines, after the positioning of the anchoring unit (1) is completed, the anchoring unit (1) is fixed with the tuyere bottom plate (22) and the tuyere side plate (24) through the fixing device (4), and a plurality of fixing devices (4) are arranged in each tuyere block body (2) to limit the spatial position of the anchoring unit (1) in the tuyere block body (2); S4, during the overall assembly of the split type steel box girder (3), the tuyere block body (2) is assembled with the steel box girder box body, before the anchoring unit (1) and the tuyere block body (2) are welded, the actual spatial coordinates of the anchor points on the dummy shaft (5) outside the box are measured by using a total station instrument, and are compared with the theoretical coordinates of the anchor points on the dummy shaft (5), the anchoring unit (1) is finely adjusted through the fixing device (4), so that the deviation between the measured anchor point coordinates and the theoretical anchor point coordinates satisfies the allowable value specified in the specification, and then the welding of the anchoring unit (1) and the tuyere block body (2) and the welding of the tuyere block body (2) and the steel box girder box body are sequentially implemented; S5, the overall assembly of the formed steel box girder is tested, the spatial coordinates of all the anchor points of the dummy shaft (5) of the total assembly segment of this round are measured by using a total station instrument, the transverse distance L between the steel anchor boxes of the left and right spans of the steel box girder, the longitudinal distance a between the steel anchor boxes of adjacent beam segments and the longitudinal displacement distance b between the steel anchor boxes of the left and right spans of the same segment are calculated based on the coordinate data, and the measured distances are compared with the corresponding theoretical distances in the three-dimensional model, so as to verify the overall linear shape of the steel box girder bridge installation and the installation precision of the steel anchor box.

2. The method for precise positioning of the steel anchor box embedded in the spatial cable plane of the steel box girder according to claim 1, characterized in that, In step S1, the dummy shaft (5) is a round rod, and a reflective sticker is pasted at the center of the end of the dummy shaft (5) for automatic tracking measurement of the total station.

3. The method for precise positioning of the steel anchor box embedded in the spatial cable plane of the steel box girder according to claim 1, characterized in that, In step S2, the blanking of the load-bearing plate (15), the pressure-bearing plate (12) and the anchor pad (13) of the steel anchor box is performed by a numerical control laser cutting machine.

4. The method for precise positioning of the steel anchor box embedded in the spatial cable plane of the steel box girder according to claim 1, characterized in that, In step S3, four sets of the fixing device (4) are arranged on the wind nozzle bottom plate (22) and the wind nozzle side plate (24) on both sides of the anchoring unit (1) for limiting the displacement and rotation of the anchoring unit (1) relative to the wind nozzle block (2).

5. The method for precise positioning of the steel anchor box embedded in the spatial cable plane of the steel box girder according to claim 1, characterized in that, The fixing device (4) comprises a fixing device base (41), an adjusting angle steel (42), a screw rod support frame (43), an angle steel fixing bolt (44), a first fixing screw rod (45) and a second fixing screw rod (46). The fixing device base (41) is used for fixing on the plate rib (25) of the wind nozzle bottom plate (22) or the wind nozzle side plate (24), and the screw rod support frame (43) is arranged on the fixing device base (41). Two adjusting angle steels (42) are connected with the fixing device base (41) through the angle steel fixing bolt (44), and an adjusting groove (48) suitable for adjusting the position of the angle steel fixing bolt (44) is formed in the fixing device base (41), the spacing between the two adjusting angle steels (42) is adjusted through the angle steel fixing bolt (44) to be embedded between the adjacent two plate ribs (25) of the wind nozzle bottom plate (22) or the wind nozzle side plate (24), and the outer wall surface of the adjusting angle steel (42) is suitable for closely contacting the outer side surface of the plate rib (25) of the wind nozzle bottom plate (22) or the wind nozzle side plate (24). The fixing device base (41) respectively extends a support plate (47) facing the outer wall surface of each of the two adjusting angle steels (42). Each support plate (47) is threadedly connected with the first fixing screw rod (45), and the first fixing screw rod (45) can abut against the inner side surface of the plate rib (25) of the wind nozzle bottom plate (22) or the wind nozzle side plate (24). The second fixing screw rod (46) is threadedly connected with the screw rod support frame (43) and can abut against the anchor partition plate (11) of the anchoring unit (1). The first fixing screw rod (45) and the second fixing screw rod (46) are both matched with a locking nut (49). The axis of the first fixing screw rod (45) is parallel to the plane of the wind nozzle bottom plate (22) or the wind nozzle side plate (24), and the axis of the second fixing screw rod (46) is perpendicular to the plane of the anchor partition plate (11).

6. The method for precise positioning of the steel anchor box embedded in the spatial cable plane of the steel box girder according to claim 5, characterized in that, The screw rod support frame (43) is provided with two groups, and each support plate (47) is provided with two first fixing screw rods (45).

7. The method for precise positioning of the steel anchor box embedded in the spatial cable plane of the steel box girder according to claim 5, characterized in that, In step S3, the anchoring unit (1) is fixed with the wind nozzle bottom plate (22) and the wind nozzle side plate (24) through the fixing device (4), which comprises: Loosen the angle steel fixing bolt (44) on the fixing device (4), adjust the adjusting angle steel (42), so that the distance between the two adjusting angle steels (42) can be embedded between the adjacent two plate ribs (25) on the tuyere bottom plate (22) or the tuyere side plate (24), and the outer wall of the adjusting angle steel (42) is in close contact with the outer side surface of the corresponding plate rib (25), and then tighten the angle steel fixing bolt (44); Adjust the first fixing screw rod (45) on both sides, so that the first fixing screw rod (45) tightly presses the outer side surface of the corresponding plate rib (25); Adjust the second fixing screw rod (46) on the upper part, so that the second fixing screw rod (46) tightly presses the anchoring partition plate (11) of the anchoring unit (1).

8. The method for precise positioning of the steel anchor box embedded in the spatial cable plane of the steel box girder according to claim 5, characterized in that, In step S4, the anchoring unit (1) is fine adjusted through the fixing device (4), including: According to the coordinate deviation value, determine the direction and adjustment amount of the anchoring unit (1) to be adjusted, rotate the second fixing screw rod (46) on the fixing device (4), change the spatial position of the anchoring unit (1) in the tuyere block (2), until the deviation between the measured coordinates of each dummy shaft (5) anchor point and the theoretical coordinates meets the specification allowable range.

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