A cantilever beam construction method based on outrigger reaction force adjustment

Abstract

The present invention belongs to the technical field of cantilever beam construction, and discloses a cantilever beam construction method based on leg reaction force adjustment, including a cantilever beam assembly stage and a bridge erection machine through-hole stage. In the cantilever beam assembly stage and the bridge erection machine through-hole stage, the leg supported on the cantilever end of the starting block or the segment beam on one side of the starting block always has a downward eccentric load pressure (i.e., the support reaction force of the leg) on ​​the cantilever beam. When the eccentric load pressure exceeds the safety threshold, it will cause the cantilever beam structure to have poor stability. Therefore, in the two construction stages, the support reaction force F1 of the leg supported on the cantilever end of the starting block or the segment beam on one side of the starting block is monitored in real time, and when the support reaction force F1 exceeds the safety threshold, the support reaction force F1 of the leg is reduced by lowering the height of the leg, thereby reducing the eccentric load pressure of the leg on the cantilever beam, and avoiding serious eccentric load phenomenon of the cantilever beam during construction.

Description

Technical Field

[0001] The invention relates to the technical field of cantilever beam construction, and in particular to a cantilever beam construction method based on outrigger reaction force adjustment. Background Art

[0002] In the current bridge construction projects, the span of bridges is getting larger and larger, and the single T-structure cantilever beam assembly process of the bridge erection machine is one of the construction processes for large-span bridges.

[0003] The main process of the single T-structure cantilever beam assembly process of the bridge erection machine is as follows: first, construct T-structure block No. 0 (starting block), use the T-structure and side piers to arrange the bridge erection machine and other cantilever assembly equipment, lift each prefabricated segment beam at the side span, transport them to the designed positions of the middle span and side span, rotate them and assemble them, and gradually extend the T-structure to both sides. After the rear T-structure is completed, the bridge erection machine passes through the hole to the front side, constructs the front T-structure, and finally completes the closure of the front T-structure and the rear T-structure.

[0004] However, during the erection and assembly of multiple segmental beams on both sides of the T-structure, the front legs of the bridge erector always acted on the cantilever end of the bridge mid-span, causing the T-structure to be in an eccentric load state. During the erection and assembly of segmental beams, the movement of the bridge erector legs, and the through-hole of the cantilever beam assembly equipment (the process of translation from the rear side to the front side), the pressure value under the front legs of the bridge erector continued to increase, that is, the pressure applied to the cantilever end of the bridge mid-span gradually increased, resulting in the aggravation of the eccentric load phenomenon of the T-structure, and in severe cases, the T-structure overturned. Summary of the invention

[0005] The purpose of the present invention is to provide a cantilever beam construction method based on leg reaction force adjustment, which can monitor and adjust the downward pressure of the front legs of the bridge erection machine on the cantilever end of the mid-span of the bridge in real time during the construction stage to avoid serious eccentric loading of the T-structure cantilever beam.

[0006] To achieve this object, the present invention adopts the following technical solutions:

[0007] Provided is a cantilever beam construction method based on outrigger reaction force adjustment, including a cantilever beam assembly stage and a bridge erection machine through-hole stage;

[0008] The cantilever beam assembly stage includes:

[0009] Three legs are arranged from front to back on the main truss of the bridge erecting machine, and the three legs are placed one by one at the center of the starting block of the cantilever beam, the cantilever end of the starting block or the segment beam on one side of the starting block, and the side span pier on one side of the cantilever beam, and the starting block is arranged on the middle span pier;

[0010] The first and second cars of the bridge erecting machine successively lift a segment beam from the same side of the starting block, and install the lifted segment beams on both sides of the starting block respectively;

[0011] The bridge erection machine through-hole stage includes:

[0012] After the construction of the rear cantilever beam is completed, the bridge erecting machine is translated from the rear construction position to the front construction position to carry out the construction of the front cantilever beam;

[0013] During the cantilever beam assembly stage and the bridge-building machine through-hole stage, the support reaction force F1 of the support leg supported on the cantilever end of the starting block or the segment beam on one side of the starting block is monitored in real time, and when the support reaction force F1 exceeds the safety threshold, the height of the support leg is lowered to reduce the support reaction force F1 of the support leg.

[0014] As a preferred solution of the cantilever beam construction method based on leg reaction force adjustment provided by the present invention, the cantilever beam assembly stage includes a rear cantilever beam assembly stage, the three legs are sequentially a first leg, a second leg and a third leg from front to back, the first leg is arranged on the cantilever end of the first starting block or on the segment beam in front of the first starting block, the second leg is arranged at the center position of the first starting block, the third leg is arranged on the rear side span pier, and the first starting block is the starting block in the rear cantilever beam;

[0015] The rear cantilever beam assembly stage includes:

[0016] S1, the first overhead crane lifts a segment of the beam, moves forward to between the first supporting leg and the second supporting leg, and then stops;

[0017] S2, the second car lifts a segment beam and moves forward to the rear side of the first starting block to be installed;

[0018] S3, lowering the height of the first supporting leg to reduce the supporting reaction force F1 of the first supporting leg;

[0019] S4, the first overhead crane moves forward with the segment beam to the front side of the first starting block to be installed;

[0020] S5. Synchronously and symmetrically install the segment beams hoisted by the first overhead traveling crane and the second overhead traveling crane.

[0021] As a preferred solution of the cantilever beam construction method based on outrigger reaction force adjustment provided by the present invention, the rear cantilever beam assembly stage further includes the following steps:

[0022] The first leg is initially supported on the cantilever end of the first starting block. After each two segment beams are added to the front side of the first starting block, the first leg is moved to the frontmost segment beam and anchored.

[0023] As a preferred solution of the cantilever beam construction method based on outrigger reaction force adjustment provided by the present invention, the rear cantilever beam assembly stage also includes:

[0024] After four segment beams are installed on both sides of the front and rear of the first starting block, the main truss of the bridge erecting machine is moved forward to a set position.

[0025] As a preferred solution of the cantilever beam construction method based on outrigger reaction force adjustment provided by the present invention, the rear cantilever beam assembly stage further includes the following steps:

[0026] S6, nine segment beams are installed in sequence on both sides of the front and rear of the first starting block, and the first leg is supported on the eighth segment beam on the front side of the first starting block;

[0027] S7, installing a first auxiliary support on the sixth segment beam at the rear side of the first starting block;

[0028] S8, moving the second carriage forward to be close to the second supporting leg;

[0029] S9, remove the third leg, move the third leg forward and install it on the seventh segment beam at the rear side of the first starting block, and then remove the first auxiliary support;

[0030] S10, the second day vehicle lifts the tenth segment beam at the rear side of the first starting block to the position to be installed;

[0031] S20, installing the tenth segment beam on the rear side of the first starting block, and fixing the segment beam on the rear side side span pier.

[0032] As a preferred solution of the cantilever beam construction method based on leg reaction force adjustment provided by the present invention, the bridge erection machine through-hole stage includes the following steps:

[0033] W1, move the first leg forward to the ninth segment beam on the front side of the first starting block, move the third leg forward to the third segment beam on the rear side of the first starting block, and move the first overhead traveling vehicle and the second overhead traveling vehicle to between the second leg and the third leg;

[0034] W2, installing a second auxiliary support on the second starting block, wherein the second starting block is the starting block in the front cantilever beam;

[0035] W3, pushing the main girder of the bridge erecting machine forward until the front end of the main girder is placed on the second auxiliary support;

[0036] W4, remove the third leg and move the third leg forward to the center position of the second starting block;

[0037] W5. Push the main truss forward until the front end of the main truss is placed on the third leg;

[0038] W6. The first overhead crane hoists the second auxiliary support to the second segment beam on the front side of the first starting block;

[0039] W7. Push the main truss forward until the main truss is separated from the second leg;

[0040] W8. Remove the second leg and move the second leg forward to the front side span pier, where the front side span pier is located on the side of the second starting block facing away from the first starting block;

[0041] W9, move the second auxiliary support forward to the position of the first leg, and push the main truss forward until the front end of the main truss is placed on the second leg;

[0042] W10, moving the first leg forward to the overhanging end at the rear side of the second starting block;

[0043] W11. Push the main truss forward until the main truss reaches the front construction position.

[0044] As a preferred solution of the cantilever beam construction method based on support leg reaction force adjustment provided by the present invention, the second auxiliary support includes a connected vertical truss and an inclined truss, the top of the vertical truss is provided with a supporting crossbeam, and at least two jacking devices are arranged on the supporting crossbeam at intervals. In the W3, the main truss is jacked by the jacking device until there is no deflection, and the support reaction force F1 is monitored in real time to ensure that it does not exceed the safety threshold;

[0045] Between W5 and W6, it also includes: adjusting the height of the third leg to make the force of the second auxiliary support zero, and monitoring the support reaction force F1 in real time so that it does not exceed the safety threshold.

[0046] As a preferred solution of the cantilever beam construction method based on support leg reaction force adjustment provided by the present invention, in the W4 and the W5, the first overhead traveling vehicle and the second overhead traveling vehicle are symmetrically arranged at the front and rear sides of the second support leg.

[0047] As a preferred solution of the cantilever beam construction method based on support leg reaction force adjustment provided by the present invention, in W7, W8, W9, W10 and W11, the first overhead traveling vehicle and the second overhead traveling vehicle are symmetrically arranged on the front and rear sides of the third support leg.

[0048] As a preferred solution of the cantilever beam construction method based on leg reaction force adjustment provided by the present invention, a pressure sensor is arranged under the first leg, and the pressure sensor is used to detect the support reaction force F1. When the detection value of the pressure sensor exceeds the safety threshold, the control unit of the first leg controls the height of the first leg to drop.

[0049] Beneficial effects of the present invention:

[0050] The present invention provides a cantilever beam construction method based on the adjustment of the reaction force of the outriggers, including the cantilever beam assembly stage and the bridge erection machine through-hole stage. In the cantilever beam assembly stage and the bridge erection machine through-hole stage, the outriggers supported on the cantilever end of the starting block or the segment beam on one side of the starting block always have a downward eccentric load pressure (i.e., the reaction force of the outriggers) on the cantilever beam. When the eccentric load pressure exceeds the safety threshold, the cantilever beam structure will be poorly stable. The main truss supported by three outriggers constitutes a primary hyperstatic, three-support point multi-span continuous beam system. According to the principle of the system, when the side support point height is reduced, its reaction force is reduced accordingly. Therefore, during the two construction stages, the support reaction force F1 of the support leg supported on the cantilever end of the starting block or the segmental beam on one side of the starting block is monitored in real time. When the support reaction force F1 exceeds the safety threshold, the support reaction force F1 of the support leg is reduced by lowering the height of the support leg, thereby reducing the eccentric load pressure of the support leg on the cantilever beam and avoiding serious eccentric load phenomenon of the cantilever beam during construction. BRIEF DESCRIPTION OF THE DRAWINGS

[0051] Figure 1 This is a first construction schematic diagram of the cantilever beam assembly stage provided by the present invention;

[0052] Figure 2 This is a second construction schematic diagram of the cantilever beam assembly stage provided by the present invention;

[0053] Figure 3 It is a third construction schematic diagram of the cantilever beam assembly stage provided by the present invention;

[0054] Figure 4 It is a fourth construction schematic diagram of the cantilever beam assembly stage provided by the present invention;

[0055] Figure 5 It is a fifth construction schematic diagram of the cantilever beam assembly stage provided by the present invention;

[0056] Figure 6 It is a sixth construction schematic diagram of the cantilever beam assembly stage provided by the present invention;

[0057] Figure 7 It is the seventh construction schematic diagram of the cantilever beam assembly stage provided by the present invention;

[0058] Figure 8 This is an eighth construction schematic diagram of the cantilever beam assembly stage provided by the present invention;

[0059] Fig. 9 It is a ninth construction schematic diagram of the cantilever beam assembly stage provided by the present invention;

[0060] Fig.10 It is the tenth construction schematic diagram of the cantilever beam assembly stage provided by the present invention;

[0061] Fig.11 This is a first construction schematic diagram of the bridge erection machine through-hole stage provided by the present invention;

[0062] Fig.12 This is a second construction schematic diagram of the bridge erection machine provided by the present invention at the hole-passing stage;

[0063] Fig.13 It is a third construction schematic diagram of the bridge erecting machine through-hole stage provided by the present invention;

[0064] Fig.14 It is a fourth construction schematic diagram of the bridge erecting machine through-hole stage provided by the present invention;

[0065] Fig.15 It is a fifth construction schematic diagram of the bridge erecting machine through-hole stage provided by the present invention;

[0066] Fig.16 It is a sixth construction schematic diagram of the bridge erecting machine through-hole stage provided by the present invention;

[0067] Fig.17 It is the seventh construction schematic diagram of the bridge erecting machine through-hole stage provided by the present invention;

[0068] Fig.18 It is an eighth construction schematic diagram of the bridge erecting machine through-hole stage provided by the present invention;

[0069] Fig.19 It is a ninth construction schematic diagram of the bridge erecting machine through-hole stage provided by the present invention;

[0070] Fig. 20 It is the tenth construction schematic diagram of the bridge erecting machine through-hole stage provided by the present invention;

[0071] Fig.21 This is the eleventh construction schematic diagram of the bridge erecting machine through-hole stage provided by the present invention;

[0072] Fig. 22 It is the twelfth construction schematic diagram of the bridge erecting machine through-hole stage provided by the present invention.

[0073] In the figure:

[0074] 1. Main truss; 2. First car; 3. Second car;

[0075] 41. first leg; 42. second leg; 43. third leg; 44. first auxiliary support; 45. second auxiliary support;

[0076] 51. First starting block; 52. Segmental beam; 53. Second starting block;

[0077] 61. Rear side span pier; 62. Rear middle span pier; 63. Front middle span pier; 64. Front side span pier. DETAILED DESCRIPTION

[0078] The present invention will be further described in detail below in conjunction with the accompanying drawings and embodiments. It is to be understood that the specific embodiments described herein are only used to explain the present invention, rather than to limit the present invention. It should also be noted that, for ease of description, only parts related to the present invention, rather than all structures, are shown in the accompanying drawings.

[0079] In the description of the present invention, unless otherwise clearly specified and limited, the terms "connected", "connected", and "fixed" should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection or an indirect connection through an intermediate medium, it can be the internal connection of two elements or the interaction relationship between two elements. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0080] In the present invention, unless otherwise clearly specified and limited, a first feature being "above" or "below" a second feature may include that the first and second features are in direct contact, or may include that the first and second features are not in direct contact but are in contact through another feature between them. Moreover, a first feature being "above", "above" and "above" a second feature includes that the first feature is directly above and obliquely above the second feature, or simply indicates that the first feature is higher in level than the second feature. A first feature being "below", "below" and "below" a second feature includes that the first feature is directly below and obliquely below the second feature, or simply indicates that the first feature is lower in level than the second feature.

[0081] In the description of this embodiment, the terms "upper", "lower", "left", "right" and other directions or positional relationships are based on the directions or positional relationships shown in the drawings, and are only for the convenience of description and simplification of operation, rather than indicating or implying that the device or element referred to must have a specific direction, be constructed and operate in a specific direction, and therefore cannot be understood as limiting the present invention. In addition, the terms "first" and "second" are only used to distinguish in the description and have no special meaning.

[0082] This embodiment provides a cantilever beam construction method based on the adjustment of the reaction force of the outriggers, including the cantilever beam assembly stage and the bridge erection machine through-hole stage. The cantilever beam assembly stage includes the rear cantilever beam assembly stage and the front cantilever beam assembly stage. After the rear cantilever beam is assembled, the bridge erection machine passes through the hole to the front side to assemble the front cantilever beam. After the front cantilever beam is constructed, the rear cantilever beam and the front cantilever beam are joined. Figures 1 to 10 , which shows the construction diagram of the rear cantilever beam assembly stage, as shown in Figures 11 to 22 , which shows the construction diagram of the bridge-building machine's through-hole stage.

[0083] The cantilever beam assembly stage includes the following steps:

[0084] (1) Three legs are arranged from front to back on the main truss 1 of the bridge erecting machine, and the three legs are placed one by one at the center of the starting block of the cantilever beam, the cantilever end of the starting block or the segment beam 52 on one side of the starting block, and the side span pier on one side of the cantilever beam. The starting block is arranged on the middle span pier;

[0085] (2) The first and second carriages 2 and 3 of the bridge erecting machine successively lift a segment beam 52 from the same side of the starting block, and install the lifted segment beam 52 on both sides of the starting block respectively.

[0086] The cantilever beam includes a starting block located in the middle, namely block No. 0. During assembly, the first car 2 and the second car 3 sequentially lift multiple segment beams 52 to both sides of the starting block, and sequentially install multiple segment beams 52 on both sides of the starting block to form the entire cantilever beam. Since the segment beams 52 are placed centrally at the construction site, the first car 2 and the second car 3 lift the segment beams 52 from the same side.

[0087] The bridge machine through-hole stage includes:

[0088] After the construction of the rear cantilever beam is completed, the bridge erecting machine is moved from the rear construction position to the front construction position to carry out the construction of the front cantilever beam.

[0089] In this embodiment, during the cantilever beam assembly stage and the bridge crane passing stage, the support reaction force F1 of the support leg on the cantilever end of the starting block or the segmented beam 52 on one side of the starting block is monitored in real time, and when the support reaction force F1 exceeds the safety threshold, the height of the support leg is lowered to reduce the support reaction force F1 of the support leg.

[0090] During the cantilever beam assembly stage and the bridge erection machine through-hole stage, the outrigger supported on the cantilever end of the starting block or the segmented beam 52 on one side of the starting block always exerts a downward eccentric load pressure on the cantilever beam (i.e., the support reaction force of the outrigger). When the eccentric load pressure exceeds the safety threshold, it will cause poor structural stability of the cantilever beam. The main truss beam 1 supported by three outriggers constitutes an over-static, three-support point multi-span continuous beam system. According to the principle of the system, when the height of the side support point decreases, its support reaction force decreases accordingly. Therefore, in the two construction stages, the support reaction force F1 of the outrigger supported on the cantilever end of the starting block or the segmented beam 52 on one side of the starting block is monitored in real time, and when the support reaction force F1 exceeds the safety threshold, the height of the outrigger is lowered to reduce the support reaction force F1 of the outrigger, thereby reducing the eccentric load pressure of the outrigger on the cantilever beam and avoiding serious eccentric load phenomenon of the cantilever beam during construction.

[0091] See also Figure 1 The three legs are the first leg 41, the second leg 42 and the third leg 43 from front to back. The first leg 41 is arranged at the cantilever end of the first starting block 51 or the segment beam 52 (such as Figure 5 The second leg 42 is arranged at the center of the first starting block 51, and the third leg 43 is arranged on the rear side span pier 61. The first starting block 51 is the starting block in the rear cantilever beam, and the first starting block 51 is arranged on the rear side middle span pier 62, and the rear side middle span pier 62 is located on the front side of the rear side span pier 61.

[0092] The rear cantilever beam assembly stage includes the following steps:

[0093] S1, the first crane 2 lifts a segment beam 52, moves forward to between the first leg 41 and the second leg 42, and then stops;

[0094] S2, the second day vehicle 3 lifts a segment beam 52 and moves forward to the rear side of the first starting block 51 to be installed;

[0095] S3, lowering the height of the first supporting leg 41 to reduce the supporting reaction force F1 of the first supporting leg 41;

[0096] S4, the first car 2 moves forward with the segment beam 52 to the front side of the first starting block 51 to be installed;

[0097] S5. Synchronously and symmetrically install the segment beams 52 lifted by the first and second car 2 and 3.

[0098] When the first carriage 2 located between the first leg 41 and the second leg 42 moves forward with the segment beam 52 to cross the first leg 41, the support reaction force F1 of the first leg 41 will gradually increase, that is, the eccentric load pressure of the first leg 41 on the cantilever beam being assembled increases. Therefore, before this, the height of the first leg 41 is adaptively lowered to reduce the support reaction force F1 of the first leg 41, so as to avoid the support reaction force F1 of the first leg 41 exceeding the safety threshold during the forward movement of the first carriage 2 at this stage.

[0099] The support reaction force F1 of the first leg 41 is proportional to the height change value of the first leg 41 and inversely proportional to the distance between the first leg 41 and the second leg 42. When the height of the first leg 41 decreases, the support reaction force F1 of the first leg 41 decreases.

[0100] In this embodiment, a pressure sensor is provided below the first leg 41, and the pressure sensor is used to detect the pressure of the first leg 41 on the cantilever beam. Since the pressure of the first leg 41 on the cantilever beam and the support reaction force of the first leg 41 are a pair of interacting forces, the detection value of the pressure sensor is the support reaction force F1. When the detection value of the pressure sensor exceeds the safety threshold, the control unit of the first leg 41 controls the height of the first leg 41 to drop.

[0101] The following reference Figures 1 to 10 The construction process of the rear cantilever beam assembly stage is explained.

[0102] See also Figure 1 At this time, only the first starting block 51 is installed on the rear middle span pier 62, and both sides of the first starting block 51 are installed segment beams 52. The first leg 41 is supported on the cantilever end of the front side of the first starting block 51, the second leg 42 is supported at the center position of the first starting block 51, and the third leg 43 is supported on the rear side span pier 61.

[0103] Continue reading Figure 1 , the first car 2 is used to lift a segment beam 52, and rotates it 90° (so that the narrower side faces the front side), and then the first car 2 moves forward with the segment beam 52 rotated 90°. The purpose of rotating the segment beam 52 90° is to avoid interference with mechanical parts due to the excessive width of the segment beam 52 when it moves forward.

[0104] See also Figure 2 The first car 2 moves forward with the segment beam 52 to between the first leg 41 and the second leg 42 and then stops. Specifically, it stops moving forward after passing the second leg 42. Then, the second car 3 lifts a segment beam 52 and moves to the rear side of the first starting block 51 (i.e. Figure 2Since the second car 3 does not pass the first leg 41 and the second leg 42, the second car 3 does not rotate after lifting the segment beam 52, that is, the wider surface of the segment beam 52 carried by the second car 3 (the surface to be assembled with the first starting block 51) faces the front side.

[0105] Continue reading Figure 2 Before the first carriage 2 moves forward, the height of the first leg 41 is lowered in advance to reduce the support reaction force F1 of the first leg 41 and reduce the influence of the support reaction force F1 gradually increasing when the first carriage 2 moves forward on the cantilever beam.

[0106] See also Figure 3 After the support reaction force F1 is adjusted, the first car 2 continues to move forward to the installation position in front of the first starting block 51, and rotates the carried segment beam 52 in the opposite direction by 90 degrees so that the side of the segment beam 52 to be spliced ​​with the first starting block 51 faces the first starting block 51.

[0107] See also Figure 4 At this time, the first segment beams 52 on the front and rear sides of the first starting block 51 are in place, and then the two segment beams 52 can be installed synchronously.

[0108] In this embodiment, the rear cantilever beam assembly stage further includes the following steps:

[0109] The first leg 41 is initially supported on the cantilever end of the first starting block 51 (see Figure 1 ), after adding two segment beams 52 on the front side of the first starting block 51, the first leg 41 is moved to the frontmost segment beam 52 and anchored.

[0110] See also Figure 5 , continue to install the second segment beam 52 (corresponding to "2#" in the figure) on the front and rear sides of the first starting block 51 according to the above steps. After the installation is completed, move the first leg 41 to the segment beam 52 on the front side of the first starting block 51, that is, move it to the second segment beam 52 on the front side of the first starting block 51, and anchor it.

[0111] Then, the third and fourth segment beams 52 are installed on the front and rear sides of the first starting block 51 according to the above steps. Figure 5 What is shown is a schematic diagram of the four segment beams 52 on the front and rear sides after installation.

[0112] It should be emphasized that when the first carriage 2 lifts each segment beam 52, it first stops between the first leg 41 and the second leg 42. Then, the second carriage 3 lifts the segment beam 52 to the right side of the installation position and stops. After that, the height of the first leg 41 is lowered to adjust the support reaction force F1 of the first leg 41. After the support reaction force F1 is adjusted, the first carriage 2 continues to move forward to move the carried segment beam 52 to the front side of the installation position.

[0113] In this embodiment, the rear cantilever beam assembly stage also includes:

[0114] After four segment beams 52 are installed on both sides of the first starting block 51, the main truss beam 1 of the bridge erecting machine is moved forward to a set position.

[0115] See also Figure 6 After four segment beams 52 are installed on both sides of the front and rear of the first starting block 51, the first car 2 and the second car 3 are driven to the side span position. Then, the support reaction force F1 at the first support leg 41 is lowered, and the main truss 1 of the bridge erecting machine is moved forward to the set position to install the subsequent segment beams 52.

[0116] See also Figure 7 After the main truss 1 is moved forward, the segment beams 52 on both sides of the first starting block 51 are installed according to the above steps. At this time, the first leg 41 is supported on the fourth segment beam 52 on the front side. Figure 7 Shown is a schematic diagram of installing the fifth segment beam 52, ensuring that it is installed symmetrically after being in place.

[0117] In this embodiment, the rear cantilever beam assembly stage further includes the following steps:

[0118] S6. Nine segment beams 52 are installed in sequence on both sides of the front and rear of the first starting block 51. At this time, the first leg 41 is supported on the eighth segment beam 52 on the front side of the first starting block 51.

[0119] like Figure 8 As shown, the installation is continued according to the installation steps of the segment beam 52 until the installation of nine segment beams 52 on the front and rear sides is completed. After the installation is completed, the first car 2 is located above the ninth segment beam 52 on the front side, and the second car 3 is located above the ninth segment beam 52 on the rear side.

[0120] S7, install the first auxiliary support 44 on the sixth segment beam 52 behind the first starting block 51, such as Fig. 9 At the same time, the first leg 41 can be moved to the sixth segment beam 52 on the front side to make the support symmetrical.

[0121] S8, move the second carriage 3 forward to be close to the second leg 42. Fig. 9As shown, the second car 3 is moved forward from above the ninth segment beam 52 on the rear side to above the first segment beam 52 on the rear side.

[0122] S9, remove the third leg 43, and move the third leg 43 forward to install it on the seventh segment beam 52 behind the first starting block 51, and then remove the first auxiliary support 44. Fig. 9 As shown, the third leg 43 is transferred to the seventh segment beam 52 on the rear side, freeing up supporting space for the rear side span pier 61 .

[0123] S10 , on the second day, the vehicle 3 lifts the tenth segment beam 52 at the rear side of the first starting block 51 to the position to be installed, and the tenth segment beam 52 is not installed at the front side of the first starting block 51 .

[0124] S20, install the tenth segment beam 52 on the rear side of the first starting block 51, and fix the segment beam 52 on the rear side span pier 61, as shown in FIG. Fig.10 As shown, the rear side span pier 61 supports the edge of the assembled cantilever beam.

[0125] In S9 , S10 , and S20 , the first car 2 is located above the ninth front segment beam 52 to serve as a counterweight.

[0126] The following reference Figures 11 to 22 Describe the construction process of the bridge-building machine's through-hole stage.

[0127] The bridge machine through-hole stage includes the following steps:

[0128] W1. Adjust the bridge erector before passing the hole. For details, see Fig.11 , move the first leg 41 forward to the ninth segment beam 52 on the front side of the first starting block 51, move the third leg 43 forward to the third segment beam 52 on the rear side of the first starting block 51, and move the first car 2 and the second car 3 between the second leg 42 and the third leg 43.

[0129] W2, see Fig.11 , the second auxiliary support 45 is installed on the second starting block 53, and the second starting block 53 is the starting block in the front cantilever beam. The front of the rear middle span pier 62 is the front middle span pier 63 and the front side span pier 64, and the second starting block 53 is installed on the front middle span pier 63. Further, the second auxiliary support 45 is installed on the overhanging end of the rear side of the second starting block 53.

[0130] W3, see Fig.12 and Fig.13, the main girder 1 of the bridge erecting machine is pushed forward until the front end of the main girder 1 is placed on the second auxiliary support 45. In the process of pushing the main girder 1 forward, the pressure sensor is used to monitor and control the support reaction force F1 at the first support leg 41 in real time so that it does not exceed the safety threshold.

[0131] In this embodiment, the second auxiliary support 45 includes a connected vertical truss and an oblique truss, and a supporting crossbeam is provided at the top of the vertical truss, and at least two jacking devices are provided on the supporting crossbeam at intervals, and illustratively, the jacking device is a jack. In W3, after the front end of the main truss 1 is placed on the second auxiliary support 45, the main truss 1 is jacked by the jacking device until there is no deflection, and the support reaction force F1 is monitored in real time to ensure that it does not exceed the safety threshold.

[0132] W4, see Fig.14 , remove the third leg 43, move the third leg 43 forward to the center of the second starting block 53, and anchor it. The third leg 43 on the second starting block 53 serves as the central support point of the main truss beam 1 of the bridge erecting machine during the assembly stage of the front cantilever beam.

[0133] W5, see Fig.15 , pushing the main truss 1 forward until the front end of the main truss 1 rests on the third leg 43. In the process of the main truss 1 moving toward the third leg 43, the second auxiliary support 45, the first leg 41 and the second leg 42 serve as three fulcrums of the main truss 1.

[0134] In W4 and W5 , the first car 2 and the second car 3 are symmetrically arranged at the front and rear sides of the second support leg 42 to ensure the balance of the main truss 1 .

[0135] Between W5 and W6 described below, it also includes: adjusting the height of the third leg 43 to make the force on the second auxiliary support 45 zero, and monitoring the reaction force F1 in real time to ensure that it does not exceed the safety threshold, so as to subsequently remove the second auxiliary support 45 safely and reliably.

[0136] W6, see Fig.16 and Fig.17 The first car 2 lifts the second auxiliary support 45 to the second segment beam 52 on the front side of the first starting block 51 and installs it.

[0137] W7, see Fig.18 , continue to push the main truss 1 forward until the main truss 1 is separated from the second leg 42. The second auxiliary support 45 is located on the second segment beam 52 in front of the first starting block 51, so that the third leg 43, the first leg 41 and the second auxiliary support 45 serve as three support points after the main truss 1 is separated from the second leg 42.

[0138] At the same time, the first carriage 2 and the second carriage 3 move to both sides of the third leg 43 and are symmetrically arranged to ensure the balance of the main truss 1.

[0139] W8, see Fig.19 , remove the second leg 42, and move the second leg 42 forward to the front side span pier 64, which is located on the side of the second starting block 53 facing away from the first starting block 51, and serves as a support for the edge of the front cantilever beam. That is, after the front cantilever beam is assembled, the tenth segment beam 52 on the front side is supported on the front side span pier 64, and the tenth segment beam 52 is not installed on the rear side of the front cantilever beam.

[0140] W9, see Fig. 20 , move the second auxiliary support 45 forward to the position of the first leg 41, and push the main truss 1 forward until the front end of the main truss 1 rests on the second leg 42. The second auxiliary support 45 can be transferred and installed on the eighth segment beam 52 on the front side of the first starting block 51, ensuring that the second auxiliary support 45 can always serve as the rightmost fulcrum of the main truss 1 during the movement before the front end of the main truss 1 rests on the second leg 42, avoiding only two supporting points, the third leg 43 and the first leg 41, during the movement.

[0141] Furthermore, a translation device may be provided at the bottom end of the second auxiliary support 45 , so that the second auxiliary support 45 can be moved to the eighth segment beam 52 on the front side of the first starting block 51 .

[0142] W10, see Fig.21 and Fig. 22 , move the first leg 41 forward to the overhanging end on the rear side of the second starting block 53. At this time, the three legs are all moved.

[0143] W11, push the main truss 1 forward until the main truss 1 reaches the front construction position. At this point, the bridge erection machine through-hole stage is completed, and then the front cantilever beam assembly operation can be carried out. During the front cantilever beam assembly operation, it is still necessary to monitor and adjust the support reaction force F1 of the first leg 41 in real time to avoid serious eccentric loading of the cantilever beam.

[0144] See also Figures 18 to 22 In W7, W8, W9, W10 and W11, the first car 2 and the second car 3 are symmetrically arranged on the front and rear sides of the third support leg 43 to ensure the balance of the main truss 1 when moving.

[0145] Exemplarily, during the process of pushing the main truss 1 forward in step W11, the first car 2 and the second car 3 continue to synchronously retreat relative to the main truss 1, so that the first car 2 and the second car 3 always remain on the front and rear sides of the third leg 43 and are symmetrically distributed until the main truss 1 reaches the front construction position.

[0146] It should be noted that in the accompanying drawings provided in this embodiment, 1#, 2#, 3#, ..., 9#, 10#, etc. represent the first segment beam, the second segment beam, the third segment beam, ..., the ninth segment beam, the tenth segment beam, etc. on the corresponding side of the first starting block.

[0147] Obviously, the above embodiments of the present invention are merely examples for clearly illustrating the present invention, and are not intended to limit the embodiments of the present invention. For those skilled in the art, various obvious changes, readjustments and substitutions can be made without departing from the protection scope of the present invention. It is not necessary and impossible to list all the embodiments here. Any modifications, equivalent substitutions and improvements made within the spirit and principles of the present invention should be included in the protection scope of the claims of the present invention.

Claims

1. A cantilever beam construction method based on outrigger reaction force adjustment, characterized in that: It includes the cantilever beam assembly stage and the bridge erection machine through-hole stage; The cantilever beam assembly stage includes: Three legs are arranged from front to back on the main truss (1) of the bridge erecting machine, and the three legs are placed one by one at the center of the starting block of the cantilever beam, the cantilever end of the starting block or the segment beam (52) on one side of the starting block, and the side span pier on one side of the cantilever beam, and the starting block is arranged on the middle span pier; The first car (2) and the second car (3) of the bridge erecting machine successively lift a segment beam (52) from the same side of the starting block, and install the lifted segment beam (52) on both sides of the starting block respectively; The bridge erection machine through-hole stage includes: After the construction of the rear cantilever beam is completed, the bridge erecting machine is translated from the rear construction position to the front construction position to carry out the construction of the front cantilever beam; During the cantilever beam assembly stage and the bridge erection machine through-hole stage, the support reaction force F1 of the support leg supported on the cantilever end of the starting block or the segment beam (52) on one side of the starting block is monitored in real time, and when the support reaction force F1 exceeds a safety threshold, the height of the support leg is lowered to reduce the support reaction force F1 of the support leg; The cantilever beam assembly stage includes a rear cantilever beam assembly stage, wherein the three legs are, from front to rear, a first leg (41), a second leg (42), and a third leg (43), wherein the first leg (41) is arranged on the cantilever end of the first starting block (51) or on the segment beam (52) in front of the first starting block (51), the second leg (42) is arranged at the center of the first starting block (51), and the third leg (43) is arranged on the rear side span pier (61), and the first starting block (51) is the starting block in the rear cantilever beam; The rear cantilever beam assembly stage includes: S1, the first overhead crane (2) lifts a segment beam (52), moves forward to between the first supporting leg (41) and the second supporting leg (42), and then stops; S2, the second car (3) lifts a segment beam (52) and moves forward to the rear side of the first starting block (51) to be installed; S3, lowering the height of the first supporting leg (41) to reduce the supporting reaction force F1 of the first supporting leg (41); S4, the first overhead travelling crane (2) moves forward with the segment beam (52) to a position to be installed in front of the first starting block (51); S5, synchronously and symmetrically installing the segment beams (52) hoisted by the first overhead traveling vehicle (2) and the second overhead traveling vehicle (3); A pressure sensor is provided below the first supporting leg (41), and the pressure sensor is used to detect the supporting reaction force F1. When the detection value of the pressure sensor exceeds a safety threshold, the control unit of the first supporting leg (41) controls the height of the first supporting leg (41) to decrease; The rear cantilever beam assembly stage also includes the following steps: S6, nine segment beams (52) are installed in sequence on both sides of the front and rear of the first starting block (51), and at this time, the first leg (41) is supported on the eighth segment beam (52) on the front side of the first starting block (51); S7, installing a first auxiliary support (44) on the sixth segment beam (52) at the rear side of the first starting block (51); S8, moving the second carriage (3) forward to be close to the second supporting leg (42); S9, removing the third supporting leg (43), and moving the third supporting leg (43) forward to install it on the seventh segment beam (52) at the rear side of the first starting block (51), and then removing the first auxiliary support (44); S10, the second vehicle (3) hoists the tenth segment beam (52) on the rear side of the first starting block (51) to a position to be installed; S20, installing the tenth segment beam (52) on the rear side of the first starting block (51), and fixing the segment beam (52) on the rear side side span pier (61); The bridge erection machine through-hole stage comprises the following steps: W1, move the first leg (41) forward to the ninth segment beam (52) on the front side of the first starting block (51), move the third leg (43) forward to the third segment beam (52) on the rear side of the first starting block (51), and move the first overhead traveling vehicle (2) and the second overhead traveling vehicle (3) between the second leg (42) and the third leg (43); W2, installing a second auxiliary support (45) on a second starting block (53), wherein the second starting block (53) is a starting block in the front cantilever beam; W3, pushing the main girder (1) of the bridge erecting machine forward until the front end of the main girder (1) rests on the second auxiliary support (45); W4. Remove the third supporting leg (43) and move the third supporting leg (43) forward to the center position of the second starting block (53); W5. Pushing the main truss (1) forward until the front end of the main truss (1) rests on the third leg (43); W6. The first overhead crane (2) hoists the second auxiliary support (45) to the second segment beam (52) on the front side of the first starting block (51); W7. Pushing the main truss (1) forward until the main truss (1) is separated from the second leg (42); W8. Remove the second supporting leg (42), and move the second supporting leg (42) forward to the front side span pier (64), wherein the front side span pier (64) is located on the side of the second starting block (53) facing away from the first starting block (51); W9, moving the second auxiliary support (45) forward to the position of the first leg (41), and pushing the main truss (1) forward until the front end of the main truss (1) rests on the second leg (42); W10, moving the first leg (41) forward to the overhanging end on the rear side of the second starting block (53); W11, pushing the main truss (1) forward until the main truss (1) reaches the front construction position; The second auxiliary support (45) comprises a connected vertical truss and an oblique truss, the top of the vertical truss is provided with a supporting crossbeam, and at least two jacking devices are arranged on the supporting crossbeam at intervals. In the W3, the main truss (1) is jacked up by the jacking device until there is no downward deflection, and the support reaction force F1 is monitored in real time to ensure that it does not exceed the safety threshold; Between W5 and W6, it also includes: adjusting the height of the third support leg (43) so that the force on the second auxiliary support (45) is zero, and monitoring the support reaction force F1 in real time to ensure that it does not exceed the safety threshold; In W4 and W5, the first overhead traveling vehicle (2) and the second overhead traveling vehicle (3) are symmetrically arranged at the front and rear sides of the second supporting leg (42); In W7, W8, W9, W10 and W11, the first overhead traveling vehicle (2) and the second overhead traveling vehicle (3) are symmetrically arranged at the front and rear sides of the third supporting leg (43); During the process of pushing the main truss (1) forward in step W11, the first overhead traveling vehicle (2) and the second overhead traveling vehicle (3) continue to synchronously retreat relative to the main truss (1), so that the first overhead traveling vehicle (2) and the second overhead traveling vehicle (3) always remain on the front and rear sides of the third supporting leg (43) and are symmetrically distributed until the main truss (1) reaches the front construction position.

2. The cantilever beam construction method based on outrigger reaction force adjustment according to claim 1, characterized in that: The rear cantilever beam assembly stage also includes the following steps: The first supporting leg (41) is initially supported on the cantilever end of the first starting block (51). After each two segment beams (52) are added to the front side of the first starting block (51), the first supporting leg (41) is moved to the frontmost segment beam (52) and anchored.

3. The cantilever beam construction method based on outrigger reaction force adjustment according to claim 1, characterized in that: The rear cantilever beam assembly stage also includes: After four segment beams (52) are installed on both sides of the first starting block (51), the main truss beam (1) of the bridge erection machine is moved forward to a set position.

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