A method and system for continuous launching of a large-span curved steel beam

Abstract

This invention discloses a method and system for continuously jacking down a large-span curved steel beam. The method includes: G100, adjusting the positions of the first and last ends of the main beam using adjusting components to ensure the overall position of the main beam is directly above the designed position, with its posture identical to the designed posture; G200, adjusting the position of the main beam to shift forward by one end, using the adjusting component at the last permanent pier as the center, rotating the front end of the main beam downwards to land at the designed position, and connecting it to the foremost permanent pier with a hinged support; G300, using the hinged support at the foremost permanent pier as the fulcrum, controlling the adjusting components to rotate the rear end of the main beam downwards until all segments of the main beam are in the designed position; G400, verifying that the beam placement is correct and there is no residual stress between the main beam and all permanent piers, installing permanent supports between all permanent piers and the main beam, and removing the hinged supports and adjusting supports. This achieves precise control over the placement position of the curved steel beam, improving the efficiency and quality of the beam placement construction.

Description

Technical Field

[0001] This invention belongs to the field of bridge construction technology, and more specifically, relates to a method and system for continuously jacking down a long-span curved steel beam. Background Technology

[0002] The traditional method of high-level bridge girder lowering involves setting up girder lowering equipment (walking machines and jacks) on the piers. First, the walking machines are used to lower the girder. Since these machines are typically about 1 meter high, when only the height of one walking machine remains, the lowering equipment needs to be replaced with shorter jacks. At the bottom of the bridge, the construction space is confined, making the use of mechanized hoisting equipment impossible, significantly increasing manpower and safety risks. When using only jacks to lower the girder, it is impossible to accurately correct the bridge's deviation, requiring additional auxiliary facilities. High-level girder lowering also presents the challenge of the large height of the lowering piers, making the stability of the piers crucial to the construction. Traditional methods only offer one safety measure.

[0003] Chinese patent CN117926723A discloses a method for launching and lowering a small-radius curved steel box girder overpass. The method is as follows: 81. Remove the front guide beam, rear guide beam, and launching supports on the cast-in-place box girder; 82. Erect a working platform on the top of the main span piers. Divide the first steel pier into steel pier one and steel pier two, depending on whether a lifting cylinder needs to be installed. Use a walking-type launching device to extend the cylinder and lift the box girder support beam. Remove steel pier one to a set height. Then, install the lifting cylinder on steel pier one. Use the walking-type launching device to retract the cylinder and place the box girder support beam on steel pier two. Remove the longitudinal distribution beam and the walking-type launching device; 83. Extend the cylinder to lift the box girder support beam. Remove steel pier two to a set height. 84. Lower the box girder support beam onto the second steel pier by retracting the lifting cylinder at the set height; 85. Remove the first steel pier at the set height and reinstall the lifting cylinder on the first steel pier; 86. Repeat the process of extending and retracting the lifting cylinder and removing the steel pier until the box girder support beam falls to the position of the transverse distribution beam; 87. Move the position of the second steel pier to align it with the support column, cut off part of the transverse distribution beam, and place the lifting cylinder on the second steel pier below the cut position of the transverse distribution beam. Remove the second steel pier using the same method as the first steel pier until the box girder support beam falls to the support column; 88. Remove the box girder support beam and support column until the steel box girder is lowered to the design elevation.

[0004] However, the Chinese patent with publication number CN117926723A has the following drawbacks: When constructing a curved bridge, due to the inherent curvature of the beam and the inconsistent heights of the permanent piers, precise control of the beam's position during lowering is crucial. This method does not provide a precise control method for lowering the beam. Therefore, a method and system for continuously jacking down large-span curved steel beams is needed to achieve precise control of the lowering position, thereby improving construction efficiency and quality. Summary of the Invention

[0005] To address the aforementioned deficiencies or improvement needs of existing technologies, this invention provides a method and system for continuously jacking down a large-span curved steel beam. The method connects the beam to the foremost permanent pier via hinged supports and employs a method centered on the adjusting support of the last permanent pier, allowing the main beam to rotate along a predetermined path. This enables precise control of the curved steel beam's placement position, improving construction efficiency and quality. Furthermore, the load is gradually and smoothly transferred from the adjusting components to the permanent supports. The use of multiple lifting and lowering of the adjusting components ensures a uniform force transition, reduces the risk of stress concentration, and guarantees the stability and safety of the bridge structure throughout the entire process.

[0006] To achieve the above objectives, according to a first aspect of the present invention, a method for continuously jacking down a large-span curved steel beam is provided, comprising the following steps:

[0007] G100. Adjust the position of the first and last ends of the main beam by adjusting the components so that the overall position of the main beam is directly above the design position and its posture is exactly the same as the design posture. Install permanent supports on all permanent piers.

[0008] G200. Adjust the position of the main beam and move it forward by one end. Using the adjustment component of the last permanent pier as the center, rotate the front end of the main beam downward to fall into the design position, and connect it to the last permanent pier with a hinge support.

[0009] G300, using the hinge support at the foremost permanent pier as the fulcrum, control the adjustment components to rotate the rear end of the main beam downwards until all segments of the main beam are in the design position.

[0010] G400, after verifying that the position of the dropped beam is correct and that there is no residual stress between the main beam and all permanent piers, fix the main beam to the permanent supports and remove the hinge supports and adjusting supports.

[0011] Furthermore, step G100 also includes the following steps:

[0012] G110. Obtain the position information of the main beam, compare it with the design position, and obtain the positional relationship between the current position and the design position of the main beam.

[0013] G120. Obtain the deviation data of the main beam based on the positional relationship. Based on the deviation data, adjust the height of each adjustment component so that the main beam is directly above its design position and its posture is exactly the same as the design posture.

[0014] Furthermore, step G200 also includes the following steps:

[0015] G210. Measure the straight-line distance between the front end of the main beam at its designed position and the current position, and the connection position of the adjustment component on the last permanent pier. Using this straight-line distance as the length standard, push the main beam forward a certain distance so that the distance between its front end and the connection position of the adjustment component on the last permanent pier is equal to this length standard.

[0016] G220, Install a hinge support at the connection position between the adjusted main beam and the adjustment component on the last permanent pier, shorten the other adjustment components except for the last end, and rotate the front end of the main beam downwards with the position of the hinge support as the center until the connection position with the adjustment component on the foremost permanent pier reaches the design position.

[0017] G230. Remove the hinge supports at the connection points of the adjustment components between the main beam and the last permanent pier. Check to ensure that the tops of all adjustment components are supported on the bottom surface of the main beam. The main beam is connected to the foremost permanent pier at the front end via hinge supports.

[0018] Furthermore, step G300 also includes the following steps:

[0019] G310. Remove the adjustment components and adjustment supports at the front end of the main beam, and check again the connection of the hinge support, the support of the adjustment components, and the overall posture of the main beam.

[0020] G320. Adjust the height and angle of the structure by adjusting the height of the adjustment components. Use the hinge support at the connection between the main beam and the foremost permanent pier as the fulcrum to rotate the rear end of the main beam downward to the design position.

[0021] G330. Based on the position of the main beam on the permanent pier in the design location, the main beam is divided into multiple drop beam segments, and the connection point of each drop beam segment is the connection point with the adjustment component.

[0022] G340. Determine the angular velocity of the main beam rotation. Calculate the height reduction speed of the corresponding height adjustment structure based on the length of each beam segment. Calculate the angle of the angle adjustment structure at the corresponding moment based on the curvature of each beam segment.

[0023] G350: Monitor the stress on each adjustment component to prevent uneven stress caused by uneven height reduction speed of the height adjustment structure, and adjust the height of the height adjustment structure according to the stress on the adjustment component.

[0024] Furthermore, in step G340, the angular velocity of the main beam rotation will be affected by external disturbances, therefore the actual change in angular velocity is as follows:

[0025]

[0026] Where I is the moment of inertia of the main beam.

[0027] θ is the rotation angle of the main beam.

[0028] B is the damping coefficient of the main beam.

[0029] K is the stiffness coefficient of the main beam.

[0030] M ext (t) represents the external moment of the main beam;

[0031] This yields the damping natural frequency of the main beam. That is, the angular velocity ω(t) is:

[0032]

[0033] Where C1 and C2 are both constants.

[0034] Furthermore, the height reduction speed of the height adjustment structure is:

[0035] v i (t)=ω(t)L i sin(θ i (t))+Δv el，i (t)+Δv nl，i (t),

[0036] Among them, v i (t) represents the rate at which the height of the i-th beam segment decreases within time t.

[0037] L i Let be the distance from the rear end of the i-th beam segment to the support point.

[0038] θ i (t) represents the angle of rotation of the i-th beam segment within time t.

[0039] Δv el，i (t) is the correction term caused by the elastic deformation of the main beam.

[0040] Δv nl，i (t) is the correction term for the main beam caused by the nonlinear behavior of the material.

[0041] Further, in step R350, the standard deviation of each adjustment component is calculated to determine whether the height reduction speed or angle change of each adjustment component needs to be adjusted. The standard deviation σ F (t) is:

[0042]

[0043] Where N is the number of adjustment components.

[0044] F i(t) represents the force on the i-th adjustment component.

[0045] This represents the average force applied to all adjustment components.

[0046] like Then it is necessary to adjust the height reduction speed or angle change of each adjustment component to make the overall force more uniform, where e is the safety factor.

[0047] Furthermore, the adjusted height reduction speed v′ of the i-th height adjustment structure h，i (t) is:

[0048] v′ h，i (t)=v h，i (t)+Δv a，i (t),

[0049] Among them, v h，i (t) represents the initial height reduction speed of the i-th height adjustment structure.

[0050] Δv a，i (t) represents the adjustment amount of the height reduction speed of the i-th height adjustment structure.

[0051] The height reduction speed adjustment amount Δv of the i-th height adjustment structure a，i (t) Specifically:

[0052]

[0053] Where, k v This is a proportional constant used to control the adjustment range.

[0054] F i (t) represents the force on the i-th adjustment component.

[0055] This represents the average force applied to all regulating components.

[0056] The adjusted i-th angle adjustment structure's angle θ′ i (t) is:

[0057] θ′ i (t)=θ i (t)+Δθ a，i (t),

[0058] Where, θ i (t) The original angle of the structure is adjusted at the i-th angle.

[0059] Δθ a,i (t) The angle adjustment amount of the i-th angle adjustment structure.

[0060] The angle adjustment amount Δθ of the i-th angle adjustment structure a，i (t) Specifically:

[0061]

[0062] Where kθ is a proportionality constant used to control the adjustment range.

[0063] F i (t) represents the force on the i-th adjustment component.

[0064] This represents the average force applied to all regulating components.

[0065] Furthermore, step G400 specifically includes:

[0066] G410. After the adjustment components have finished operating, check that all parts of the main beam have reached the design position and that the deviation from the design position is within the allowable error range.

[0067] G420. Install permanent supports on each permanent pier. After the lower support plate of the permanent support is fixed to the upper surface of the permanent pier, remove the hinge support at the front end of the main beam.

[0068] G430, lower all adjusting components slightly at the same speed until all adjusting components are no longer under force, at which point the force on the main beam is borne by the permanent support;

[0069] G440. Raise all the adjustment components slightly at the same speed until they collectively support the main beam. At this point, the permanent support does not bear the force of the permanent support.

[0070] G450, again lower all the adjustment components slightly at the same speed until all the adjustment components are no longer under force, so that the permanent support can support the main beam;

[0071] G460. Fix the upper support plate of the permanent support to the bottom surface of the main beam, remove the adjustment components and adjustment supports, and complete the lowering of the main beam.

[0072] According to a second aspect of the present invention, a continuous jacking system for large-span curved steel beams is provided, comprising:

[0073] The adjustment module is used to adjust the position of the first and last ends of the main beam by adjusting the components, so that the overall position of the main beam is directly above the design position and its posture is exactly the same as the design posture.

[0074] The first rotating module is used to adjust the position of the main beam and move it forward by one end. With the adjustment component of the last permanent pier as the center, the front end of the main beam is rotated downward to fall to the design position, and is connected to the last permanent pier by a hinge support.

[0075] The second rotation module is used to control the adjustment component to rotate the rear end of the main beam downwards, using the hinge support at the foremost permanent pier as the fulcrum, until all segments of the main beam are in the designed position.

[0076] The fixed module is used to verify that the position of the dropped beam is correct, that there is no residual stress between the main beam and all permanent piers, that permanent supports are installed between all permanent piers and the main beam, and that hinge supports and adjusting supports are removed.

[0077] In summary, compared with the prior art, the above-described technical solutions conceived by this invention can achieve the following beneficial effects:

[0078] 1. The beam lowering method of the present invention achieves connection with the foremost permanent pier through hinged supports, and adopts a method with the adjusting support of the last permanent pier as the center, so that the main beam can rotate along a predetermined path, thereby avoiding unnecessary stress concentration. This phased and well-controlled beam lowering method not only improves construction efficiency, but also greatly reduces the impact on the surrounding environment, and ensures the stability and safety of the bridge structure throughout the process.

[0079] 2. After the main beam is placed, the beam placement method of the present invention confirms through testing that it is accurately placed on each permanent pier without residual stress. This method greatly improves the safety and durability of the bridge and simplifies the later maintenance work.

[0080] 3. The beam lowering method of the present invention gradually and smoothly transfers the load from the adjustment component to the permanent support. By using the method of raising and lowering the adjustment component multiple times, the uniform transition of force is ensured, the risk of stress concentration is reduced, and the safety and durability of the bridge are improved. In addition, the final fixing is carried out only after repeatedly confirming that the permanent support can fully bear the weight of the main beam, which further enhances the stability of the entire structure. Attached Figure Description

[0081] Figure 1 This is a flowchart illustrating a continuous jacking method for a large-span curved steel beam according to an embodiment of the present invention.

[0082] Figure 2 This is a schematic diagram of the specific process of step S400 of a continuous jacking method for a large-span curved steel beam according to an embodiment of the present invention.

[0083] Figure 3 This is a schematic diagram of the specific process of step S500 in a continuous jacking method for a large-span curved steel beam according to an embodiment of the present invention.

[0084] Figure 4 This is a schematic diagram of a continuous jacking device for a large-span curved steel beam according to an embodiment of the present invention;

[0085] Figure 5 This is an embodiment of the present invention. Figure 4 Enlarged structural diagram of section A;

[0086] Figure 6 This is a schematic diagram of the installation structure of the jacking drive assembly of a continuous jacking device for large-span curved steel beams according to an embodiment of the present invention;

[0087] Figure 7 This is a schematic diagram of the installation structure of the guide and correction component of a continuous jacking device for large-span curved steel beams according to an embodiment of the present invention;

[0088] Figure 8 This is a flowchart illustrating a method for continuously jacking down a large-span curved steel beam according to an embodiment of the present invention.

[0089] Figure 9 This is a flowchart illustrating step G100 in a method for continuously jacking down a large-span curved steel beam according to an embodiment of the present invention.

[0090] Figure 10 This is a flowchart illustrating step G200 in a method for continuously jacking down a large-span curved steel beam according to an embodiment of the present invention.

[0091] Figure 11 This is a flowchart illustrating step G300 in a method for continuously jacking down a large-span curved steel beam according to an embodiment of the present invention.

[0092] Figure 12 This is a flowchart illustrating step G400 in a method for continuously jacking down a large-span curved steel beam according to an embodiment of the present invention.

[0093] In all the accompanying drawings, the same reference numerals denote the same technical features, specifically: 1-permanent pier, 2-main beam, 3-front guide beam, 4-rear guide beam, 5-support assembly, 501-temporary jacking support, 502-temporary correction support, 503-temporary support support, 504-main beam splicing support, 6-jacking drive assembly, 7-guide and correction assembly, 8-adjusting support. Detailed Implementation

[0094] To make the objectives, technical solutions, and advantages of this invention clearer, the invention will be further described in detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative and not intended to limit the invention. Furthermore, the technical features involved in the various embodiments of this invention described below can be combined with each other as long as they do not conflict with each other.

[0095] Example 1

[0096] like Figure 1As shown, this embodiment of the invention provides a method for continuous jacking of large-span curved steel beams, specifically including the following steps:

[0097] S100, a jacking temporary support 501 and a correction temporary support 502 are set on both sides of the permanent pier 1, and a supporting temporary support 503 and a main beam splicing support 504 are set between the transverse permanent piers 1.

[0098] S200, a permanent support is installed on the top of the permanent pier 1, a jacking drive assembly 6 is set on the jacking temporary support 501, a guide correction assembly 7 is set on the correction temporary support 502, and a rolling assembly is set on the support temporary support 503.

[0099] S300. Each segment of the main beam 2 is further divided into multiple prefabricated segments for prefabrication. A front guide beam 3 is set at the front end of the frontmost prefabricated segment, and a rear guide beam 4 is set at the rear end of the last prefabricated segment, and fixed to the jacking drive assembly 6.

[0100] S400, on the main beam splicing bracket 504, the jacking drive assembly 6 pushes the rear guide beam 4 to connect the last precast segment with the front precast segment and weld them together. The jacking drive assembly 6 then pulls the rear guide beam 4 back to the last end, places a new precast segment to make it the new last precast segment, and repeats the jacking to complete the welding of all precast segments of the current segment.

[0101] S500, after removing the jacking drive assembly 6 from the rear guide beam 4, install it at the front end of the front guide beam 3. The jacking drive assembly 6 pulls the front guide beam 3 to move the spliced ​​segments of the main beam 2 forward, so that the front guide beam 3 reaches the next permanent pier 1. At this time, the main beam splicing bracket 504 is freed up.

[0102] Before and after steps S600 and S500, the guide correction component 7 is used to correct the axial position of the main beam 2, so that it is always kept within a reasonable error range during the installation process. At the same time, the height of the adjustment support 8 is adjusted so that the forward direction of the main beam 2 matches its curvature.

[0103] S700, Remove the jacking drive assembly 6 and the rear guide beam 4, and install them at the rear end of the next precast segment. Repeat steps S400-S600 until all segments of the main beam 2 are jacked and installed.

[0104] S800. Install a hinge support on the foremost permanent pier 1, so that the foremost end of the main beam 2 is connected to the hinge support. Using the hinge support as a fulcrum, rotate the main beam 2 so that it falls onto the permanent supports on other permanent piers 1 and is fixed.

[0105] S900, Remove the hinge support on the foremost permanent pier 1, install a permanent support on the permanent pier 1 and fix it to the foremost end of the main beam 2.

[0106] By dividing the main beam 2 into different segments, and then dividing each segment into multiple prefabricated segments, multiple segments can be spliced ​​at the same construction site, saving construction space and reducing construction steps. At the same time, when constructing the front segment, the rear segment is not installed, avoiding the entire main beam 2 from colliding due to the overall curvature, which would cause construction difficulties.

[0107] The precast sections are moved to their designed positions by a combination of jacking and dragging. For short precast sections, jacking is used to ensure better contact with the preceding precast section for welding and fixing. For long sections, dragging is used to ensure more even stress distribution during movement and to avoid frequent swaying.

[0108] Since the main beam 2 is formed as a beam slab with a certain arc shape, during the jacking process, it is necessary to control the bottom surface of its foremost precast section to always remain above the support component 5. Therefore, during the jacking process of all precast sections, it is necessary to plan the path of each precast section and use the adjusting support 8 to adjust the height of different segments of the main beam 2 to achieve precise control.

[0109] like Figure 2 As shown, in step S400, since the lengths and curvatures of different segments of the main beam 2 are different, it is necessary to calculate the overall angle, height, and position of different segments. The specific steps are as follows:

[0110] S410. Based on the design parameters, the terrain, permanent pier 1 and the main beam 2 after completion are modeled in three dimensions to obtain a scaled three-dimensional model of the completed bridge.

[0111] S420. In the completed scale bridge 3D model, the main beam 2 is positioned above the support component 5. The main beam 2 is moved to the rear end. The optimal advancement route for different segments is simulated by working backward.

[0112] S430. Cut out the optimal advancement path of each segment on the main beam splicing support 504, obtain the attitude of each segment on the main beam splicing support 504, and then use the position of the current precast segment and its rear precast segment to simulate and determine the optimal advancement path of each precast segment.

[0113] S440. Based on the optimal advancement route of the precast segments on each segment, adjust the shape of the main beam splicing bracket 504 to fit the angle and positional relationship of the precast segments on their optimal advancement route, and then advance them according to the optimal advancement route of the precast segments to connect them into segments.

[0114] In step S420, during the reverse calculation process, the final landing point of each segment is on the main beam splicing support 504, and the route recording of that segment ends after the front end face of each segment reaches the main beam splicing support 504.

[0115] During the reverse calculation process, the optimal propulsion route is the one that generates the least amount of additional motion during the movement of the main beam 2. This route is determined by the rotation frequency, rotation angle, vertical center of gravity movement frequency, and vertical center of gravity movement distance of the main beam 2, specifically by the Extra Motion Index (EMI). The lower the EMI value, the more suitable the corresponding propulsion route is for selection. The EMI is:

[0116]

[0117] in, This refers to the cumulative angular velocity of the main beam during the entire jacking process, i.e., the amplitude of rotation.

[0118] The cumulative angular acceleration of the main beam during the entire jacking process, i.e., the change in rotational rate,

[0119] This refers to the cumulative vertical acceleration of the main beam's center of gravity during the entire jacking process, i.e., the amplitude of the center of gravity's vertical vibration.

[0120] f v The frequency of the main beam's center of gravity movement.

[0121] f h The horizontal displacement frequency of the main beam

[0122] D h The horizontal offset of the center of gravity of the main beam.

[0123] This refers to the cumulative acceleration of the main beam's center of gravity during the entire jacking process, i.e., the acceleration of the center of gravity in space.

[0124] The position vector r of the center of gravity of the main beam c (t) is:

[0125] r c (t) = [x(t), y(t), z(t)] T ,

[0126] Where x(t), y(t), and z(t) are the front-back, left-right, and vertical coordinates of the center of gravity of the main beam, respectively.

[0127] The angular velocity ω(t) of the main beam rotation is:

[0128]

[0129] Here, R(t) is the attitude matrix of the main beam, which is a rotation matrix with respect to time.

[0130] In step S430, the position and orientation of the prefabricated segment are as follows:

[0131]

[0132] Where t is the translation matrix, representing the change in position.

[0133] R is the rotation matrix, representing the change in attitude.

[0134] (x m y m , z m () represents the coordinates of the centroid of the precast segment m.

[0135] (x′ m y′ m , z′ m ) represents the change in the position coordinates of the center of gravity of the precast segment m.

[0136] The translation matrix t is:

[0137]

[0138] The rotation matrix R is:

[0139] R = R z (γ m )·R y (β m )·R x (α m ),

[0140] Among them, R x (α m Let be the rotation matrix about the x-axis.

[0141] R y (β m Let be the rotation matrix about the y-axis.

[0142] R z (γ m ) is the rotation matrix about the z-axis.

[0143] The rotation matrix R around the x-axis x (α m )for:

[0144]

[0145] Rotation matrix R around the y-axis y (β m )for:

[0146]

[0147] Rotation matrix R about the z-axis z (γ m )for:

[0148]

[0149] Where, α m ,β m γ m These are the angles of the precast segment m around the x, y, and z axes, respectively.

[0150] like Figure 3 As shown, step S500 also includes the following steps:

[0151] S510. Construct a functional relationship between the position of the leading beam 3 and the height of all adjusting supports 8 according to the optimal propulsion route, and set an interlock between the leading beam 3 and the adjusting supports 8.

[0152] S520. Set up a temporary jacking support 501 along the optimal advancement route of the foremost segment. Remove the jacking drive assembly 6 from the rear guide beam 4 and install it at the front end of the front guide beam 3. The jacking drive assembly 6 drives the front guide beam 3 to move along the temporary jacking support 501.

[0153] S530. During the forward movement of the guide beam 3, the adjusting support 8 determines the height of the main beam 2 at its current support point based on the position of the guide beam 3, and then adjusts its own height to support the main beam 2, so that each segment of the main beam 2 is always kept in the optimal advancement path.

[0154] In step S520, the position s of the guide beam 3 d (t) is:

[0155]

[0156] Among them, s t (t) represents the position of the temporary support being pushed down directly below the guide beam.

[0157] v d (τ) represents the speed of the push drive component.

[0158] The speed v of the push drive component d (τ) is determined by the dynamic equations, specifically:

[0159]

[0160] The total mass of the m-push drive assembly, the front guide beam, the main beam, and the rear guide beam is included.

[0161] For the acceleration of the push-driven component,

[0162] F d The driving force provided for the driving components

[0163] Ff This includes resistance, including friction.

[0164] In step S530, the height h of the adjusting support 8 is... m (t) is:

[0165]

[0166] Among them, v h (t) represents the speed at which the height of the support is adjusted.

[0167] h m (t-Δt) represents the height of the support at the previous moment.

[0168] After step S700, it is also necessary to remove the front guide beam 3, the jacking temporary support 501, the correction temporary support 502, and the main beam splicing support 504 to make room for the subsequent beam lowering and fixing.

[0169] Example 2

[0170] like Figure 4 , 5 As shown, this embodiment of the invention provides a continuous jacking device for a long-span curved steel beam, including support components 5 on both sides of a permanent pier 1, a jacking drive component 6 on the support components 5, a guide and correction component 7 on the support components 5, and an adjusting support 8. The drive beam 2 is divided into multiple segments, and each segment of the main beam 2 is fixedly connected by welding. Each segment includes multiple precast sections, and each precast section is also fixedly connected by welding.

[0171] The support assembly 5 includes a main beam splicing bracket 504 located at the rear end of the last permanent pier 1, a jacking temporary bracket 501 located on both sides of the main beam splicing bracket 504 and the permanent pier 1, a supporting temporary bracket 503 located on both sides of the main beam splicing bracket 504 and the permanent pier 1, and a correction temporary bracket 502.

[0172] like Figure 6As shown, the jacking drive assembly 6 uses a motor and a reducer for power. The output end of the reducer is connected to a gear via a universal coupling. The gear engages with a rack, which is segmented and fixed to the jacking temporary support 501 by an I-beam. The motor is a dual-motor system, one in operation and one on standby. When started, the drive gear moves on the rack, thereby driving the main beam 2 forward on the jacking temporary support 501 via the front guide beam 3 or the rear guide beam 4. The drive gear is surrounded by a housing, with the gear protruding from the bottom of the housing. A set of vertical and horizontal limiting wheels are provided on both sides of the protruding bottom portion of the gear. Each set of vertical limiting wheels includes upper and lower guide wheels with a gap between them, the gap being the same thickness as the I-beam of the rack, just enough to clamp the rack and the I-beam. Each set of horizontal limiting wheels includes horizontally positioned guide wheels, the distance between the two horizontal guide wheels being the same as the width of the I-beam, clamping both sides of the I-beam. The vertical limiting wheel prevents the gear and rack from moving vertically during the propulsion process, thus preventing them from breaking the meshing. The horizontal guide wheel prevents the gear and rack from moving horizontally during the propulsion process, thus preventing them from breaking the meshing. The vertical limiting wheel and the horizontal guide wheel are used together to limit the gear and prevent it from disengaging from the rack during the movement, thus affecting the propulsion of the main beam 2.

[0173] like Figure 7 As shown, the guiding and correcting assembly 7 is mounted on the temporary correction support 502. It includes a guide roller and a hydraulic cylinder. The guide roller includes a guide wheel, a rubber sleeve, a limiting plate, and a support structure. The support structure is used to fix the guide roller to the output end of the hydraulic cylinder. The hydraulic cylinder is fixed to the temporary correction support 502. The hydraulic cylinder pushes the guide roller, causing the guide wheel to exert a thrust on the side wall of the main beam 2, thereby adjusting the lateral position of the main beam 2. The rubber sleeve is fitted onto the guide wheel to reduce the force generated by the collision between it and the main beam 2.

[0174] The adjusting support 8 is mounted on the temporary support 503, and a roller is provided on its top. An adjusting assembly is also provided between the roller and the adjusting support 8. The adjusting assembly includes a height adjusting structure and an angle adjusting structure. The height adjusting structure is used to adjust the height of the roller so that it always fits against the bottom of the main beam 2 to provide support. Since the main beam 2 is a curved beam and at least two rollers are used side by side, only one roller may be under load, causing it to overload and be damaged. Therefore, the angle adjusting structure adjusts the height of each roller individually so that the side-by-side rollers form an angle to fit against the bottom surface of the main beam 2, making the force more even, extending the service life of the device, and enhancing the device's performance.

[0175] Example 3

[0176] like Figure 8As shown, in step S800, since the main beam 2 after assembly has a certain curvature and the lengths between different segments of the main beam 2 are different, the spacing and height of the permanent piers 1 are also different. Therefore, in this case, the beam lowering step after the main beam 2 is pushed needs to control the position of the main beam 2 and the angle between it and each permanent pier in order to achieve the purpose of precise beam lowering.

[0177] Therefore, embodiments of the present invention provide a method for continuously jacking down a large-span curved steel beam, specifically including the following steps:

[0178] G100. Adjust the position of the first and last ends of the main beam 2 by adjusting the components so that the overall position of the main beam 2 is directly above the design position and its posture is exactly the same as the design posture. Install permanent supports on all permanent piers 1.

[0179] G200, Adjust the position of the main beam 2 and move it forward by one end. With the adjustment component of the last permanent pier 1 as the center, rotate the front end of the main beam 2 downward to fall into the design position, and connect it to the last permanent pier 1 with the hinge support.

[0180] G300, using the hinge support at the foremost permanent pier 1 as the fulcrum, control the adjustment component to rotate the rear end of the main beam 2 downwards until all segments of the main beam 2 are in the design position.

[0181] G400, after verifying that the position of the dropped beam is correct and that there is no residual stress between the main beam 2 and all permanent piers 1, fix the main beam 2 to the permanent supports and remove the hinge supports and adjusting supports.

[0182] like Figure 9 As shown, step G100 also includes the following steps:

[0183] G110. Obtain the position information of main beam 2, compare it with the design position, and obtain the positional relationship between the current position and the design position of main beam 2.

[0184] G120. Obtain the deviation data of the main beam 2 based on the positional relationship. Based on the deviation data, adjust the height of each adjustment component so that the main beam 2 is directly above its designed position and its posture is exactly the same as the designed posture.

[0185] In step G110, the positional relationship between the current position and the design position of the main beam 2 is required to include: both sides of the current position and the design position of the main beam 2 are in the same plane; both end faces of the current position and the design position are in the same plane; and the upper and lower surfaces of the current position and the design position are parallel.

[0186] like Figure 10 As shown, step G200 also includes the following steps:

[0187] G210. Measure the straight-line distance between the front end of the main beam 2 at its designed position and the current position and the connection position of the adjustment component on the last permanent pier 1. Using this straight-line distance as the length standard, push the main beam 2 forward a certain distance so that the distance between its front end and the connection position of the adjustment component on the last permanent pier 1 is equal to the length standard.

[0188] G220, Install a hinge support at the connection position between the adjusted main beam 2 and the adjustment component on the last permanent pier 1, shorten the other adjustment components except for the last end, and rotate the front end of the main beam 2 downwards to the design position with the connection position of the adjustment component on the foremost permanent pier 1 using the position of the hinge support as the center.

[0189] G230. Remove the hinge supports at the connection points of the adjustment components on the main beam 2 and the last permanent pier 1. Check and ensure that the tops of all adjustment components are supported on the bottom surface of the main beam 2. The main beam 2 is connected to the last permanent pier 1 at the connection point via hinge supports.

[0190] like Figure 11 As shown, step G300 also includes the following steps:

[0191] G310. Remove the adjustment component and adjustment support 8 at the front end of the main beam 2, and check the connection of the hinge support, the support of the adjustment component, and the overall posture of the main beam 2 again.

[0192] G320. Adjust the height and angle of the structure by adjusting the height of the adjustment components. Using the hinge support at the connection between the main beam 2 and the foremost permanent pier 1 as the fulcrum, rotate the rear end of the main beam 2 downward to the design position.

[0193] G330. Based on the position of the main beam 2 on the permanent pier 1 in the design position, the main beam 2 is divided into multiple beam-dropping segments, and the connection point of each beam-dropping segment is the connection point with the adjustment component.

[0194] G340. Determine the angular velocity of the main beam 2 rotation. Calculate the height reduction speed of the corresponding height adjustment structure based on the length of each beam segment. Calculate the angle of the angle adjustment structure at the corresponding moment based on the curvature of each beam segment.

[0195] G350: Monitor the stress on each adjustment component to prevent uneven stress caused by uneven height reduction speed of the height adjustment structure, and adjust the height of the height adjustment structure according to the stress on the adjustment component.

[0196] In step G340, the angular velocity of the main beam 2 will be affected by external disturbances, therefore the actual change in angular velocity is as follows:

[0197]

[0198] Where I is the moment of inertia of the main beam.

[0199] θ is the rotation angle of the main beam.

[0200] B is the damping coefficient of the main beam.

[0201] K is the stiffness coefficient of the main beam.

[0202] M ext (t) represents the external moment of the main beam.

[0203] Thus, the damping natural frequency of main beam 2 is obtained. That is, the angular velocity ω(t) is:

[0204]

[0205] Where C1 and C2 are both constants.

[0206] The height reduction speed of the height adjustment structure is:

[0207] v i (t)=ω(t)L i sin(θ i (t))+Δv el，i (t)+Δv nl，i (t),

[0208] Among them, v i (t) represents the rate at which the height of the i-th beam segment decreases within time t.

[0209] L i Let be the distance from the rear end of the i-th beam segment to the support point.

[0210] θ i (t) represents the angle of rotation of the i-th beam segment within time t.

[0211] Δv el，i (t) is the correction term caused by the elastic deformation of the main beam.

[0212] Δv nl，i (t) is the correction term for the main beam caused by the nonlinear behavior of the material.

[0213] The correction term Δv for the main beam caused by elastic deformation el，i (t) is described by the Euler-Bernoulli beam equations, specifically:

[0214]

[0215] Where w is the deflection of the main beam.

[0216] M(x, t) is the bending moment of the main beam.

[0217] G is the shear modulus of the main beam.

[0218] I is the moment of inertia of the main beam.

[0219] The main beam is subject to a correction term Δv caused by the nonlinear behavior of the material. nl，i (t) is described by the Prandtl-Reuss equation, specifically:

[0220]

[0221] in, The plastic strain rate of the main beam,

[0222] λ is the plastic multiplier of the main beam.

[0223] σ is the stress tensor of the main beam.

[0224] The plastic multiplier λ of the main beam is specifically:

[0225]

[0226] Where f(σ, q) is the yield function of the main beam.

[0227] q is the hardening parameter for the main beam.

[0228] f0 is the initial yield stress.

[0229] The angle of change of the angle adjustment structure is:

[0230]

[0231] Where, Δθ i (t) represents the angle that the i-th angle adjustment structure changes within time t.

[0232] k i (t) represents the curvature of the main beam at the i-th angle adjustment structure.

[0233] L i Let be the distance from the rear end of the i-th beam segment to the support point.

[0234] In step R350, the standard deviation of each adjustment component is calculated to determine whether the height reduction speed or angle change of each adjustment component needs to be adjusted. The standard deviation σ... F (t) is:

[0235]

[0236] Where N is the number of adjustment components.

[0237] F i(t) represents the force on the i-th adjustment component.

[0238] This represents the average force applied to all regulating components.

[0239] like Then it is necessary to adjust the height reduction speed or angle change of each adjustment component to make the overall force more uniform, where e is the safety factor.

[0240] The adjusted height reduction speed v′ of the i-th height adjustment structure h，i (t) is:

[0241] v′ h，i (t)=v h，i (t)+Δv a，i (t),

[0242] Among them, v h，i (t) represents the initial height reduction speed of the i-th height adjustment structure.

[0243] Δv a，i (t) represents the adjustment amount of the height reduction speed of the i-th height adjustment structure.

[0244] The height reduction speed adjustment amount Δv of the i-th height adjustment structure a，i (t) Specifically:

[0245]

[0246] Where, k v This is a proportional constant used to control the adjustment range.

[0247] F i (t) represents the force on the i-th adjustment component.

[0248] This represents the average force applied to all regulating components.

[0249] The adjusted i-th angle adjustment structure's angle θ′ i (t) is:

[0250] θ′ i (t)=θ i (t)+Δθ a，i (t),

[0251] Where, θ i (t) The original angle of the structure is adjusted at the i-th angle.

[0252] Δθ a,i (t) The angle adjustment amount of the i-th angle adjustment structure.

[0253] The angle adjustment amount Δθ of the i-th angle adjustment structure a，i (t) Specifically:

[0254]

[0255] Where kθ is a proportionality constant used to control the adjustment range.

[0256] F i (t) represents the force on the i-th adjustment component.

[0257] This represents the average force applied to all regulating components.

[0258] like Figure 12 As shown, step G400 further includes:

[0259] G410. After the adjustment component has finished its operation, check that all parts of the main beam 2 have reached the design position and that the deviation from the design position is within the allowable error range.

[0260] G420. Install permanent supports on each permanent pier 1. After the lower support plate of the permanent support is fixed to the upper surface of the permanent pier 1, remove the hinge support at the front end of the main beam 2.

[0261] G430, lower all adjustment components slightly at the same speed until all adjustment components are no longer under force, at which point the force of the main beam 2 is borne by the permanent support;

[0262] G440, raise the height of all adjustment components slightly at the same speed until they jointly support the main beam 2. At this time, the permanent support does not bear the force of the permanent support.

[0263] G450, again lower all the height of the adjustment components at the same speed and slightly until all the adjustment components are no longer under force, so that the permanent support supports the main beam 2;

[0264] G460. Fix the upper support plate of the permanent support to the bottom surface of the main beam 2, remove the adjustment component and the adjustment support 8, and complete the lowering of the main beam 2.

[0265] Example 4

[0266] This invention provides a continuous jacking system for large-span curved steel beams, specifically including:

[0267] The adjustment module is used to adjust the head and tail positions of the main beam 2 through the adjustment components, so that the overall position of the main beam 2 is directly above the design position, and its posture is exactly the same as the design posture.

[0268] The first rotating module is used to adjust the position of the main beam 2 and move it forward by one end. With the adjustment component of the last permanent pier 1 as the center, the front end of the main beam 2 is rotated downward to fall to the design position, and is connected to the frontmost permanent pier 1 by a hinge support.

[0269] The second rotation module is used to control the adjustment component to rotate the rear end of the main beam 2 downwards, using the hinge support at the foremost permanent pier 1 as the fulcrum, until all segments of the main beam 2 are in the designed position.

[0270] The fixed module is used to verify that the position of the dropped beam is correct, that there is no residual stress between the main beam 2 and all permanent piers 1, that permanent supports are installed between all permanent piers 1 and the main beam 2, and that hinge supports and adjusting supports are removed.

[0271] Those skilled in the art will readily understand that the above description is merely a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions, and improvements made within the spirit and principles of the present invention should be included within the scope of protection of the present invention.

Claims

1. A method for continuously jacking down a large-span curved steel beam, characterized in that, Includes the following steps: G100. Adjust the position of the first and last ends of the main beam (2) by adjusting the components so that the overall position of the main beam (2) is directly above the design position and its posture is exactly the same as the design posture. Install permanent supports on all permanent piers (1). G200, Adjust the position of the main beam (2) and move it forward by one end. With the adjustment component of the last permanent pier (1) as the center, rotate the front end of the main beam (2) downward to fall to the design position and connect it to the last permanent pier (1) with the hinge support. G300, using the hinge support at the frontmost permanent pier (1) as the fulcrum, control the adjustment component to make the rear end of the main beam (2) rotate downward until all segments of the main beam (2) fall into the design position; G400. After confirming that the position of the dropped beam is correct and that there is no residual stress between the main beam (2) and all permanent piers (1), fix the main beam (2) to the permanent support and remove the hinge support and the adjusting support.

2. The method for continuously jacking down a large-span curved steel beam according to claim 1, characterized in that, Step G100 also includes the following steps: G110. Obtain the position information of the main beam (2), compare it with the design position, and obtain the positional relationship between the current position and the design position of the main beam (2); G120. Obtain the deviation data of the main beam (2) based on the positional relationship. Based on the deviation data, adjust the height of each adjustment component so that the main beam (2) is directly above its design position and its posture is exactly the same as the design posture.

3. The method for continuously jacking down a large-span curved steel beam according to claim 1, characterized in that, Step G200 also includes the following steps: G210. Measure the straight-line distance between the front end of the main beam (2) at its designed position and the current position and the connection position of the adjustment component on the last permanent pier (1). Using this straight-line distance as the length standard, push the main beam (2) forward a certain distance so that the distance between its front end and the connection position of the adjustment component on the last permanent pier (1) is equal to this length standard. G220, Install a hinge support at the connection position between the adjusted main beam (2) and the adjustment component on the last permanent pier (1), shorten the other adjustment components except the last end, and rotate the front end of the main beam (2) downwards to the design position with the connection position of the adjustment component on the last permanent pier (1) using the position of the hinge support as the center. G230. Remove the hinge support at the connection position of the adjustment component on the main beam (2) and the last permanent pier (1), check and ensure that the top of all adjustment components is supported on the bottom surface of the main beam (2), and connect the front end of the main beam (2) and the frontmost permanent pier (1) through the hinge support.

4. A method for continuously jacking down a large-span curved steel beam according to any one of claims 1-3, characterized in that, Step G300 also includes the following steps: G310. Remove the adjustment component and adjustment support (8) at the front end of the main beam (2), and check the connection of the hinge support, the support of the adjustment component, and the overall posture of the main beam (2) again. G320. Adjust the height and angle of the structure by adjusting the height of the adjustment component. With the hinge support at the connection between the main beam (2) and the frontmost permanent pier (1) as the fulcrum, the rear end of the main beam (2) is rotated downward to the design position. G330. Based on the position of the main beam (2) on the permanent pier (1) in the design position, the main beam (2) is divided into multiple beam-dropping segments. The connection point of each beam-dropping segment is the connection point between it and the adjustment component. G340. Determine the angular velocity of the main beam (2) rotation. Calculate the height reduction speed of the corresponding height adjustment structure based on the length of each drop beam segment. Calculate the angle of the angle adjustment structure at the corresponding moment based on the curvature of each drop beam segment. G350: Monitor the stress on each adjustment component to prevent uneven stress caused by uneven height reduction speed of the height adjustment structure, and adjust the height of the height adjustment structure according to the stress on the adjustment component.

5. The method for continuously jacking down a large-span curved steel beam according to claim 4, characterized in that, In step G340, the angular velocity of the main beam (2) will be affected by external disturbances, so the actual change in angular velocity is: Where I is the moment of inertia of the main beam. θ is the rotation angle of the main beam. B is the damping coefficient of the main beam. K is the stiffness coefficient of the main beam. M ext (t) represents the external moment of the main beam; Thus, the damping natural frequency of the main beam (2) is obtained. That is, the angular velocity ω(t) is: Where C1 and C2 are both constants.

6. The method for continuously jacking down a large-span curved steel beam according to claim 5, characterized in that, The height reduction speed of the height adjustment structure is: v i (t)=ω(t)L i sin(θ i (t))+Δv el，i (t)+Δv nl，i (t), Among them, υ i (t) represents the rate at which the height of the i-th beam segment decreases within time t. L i Let be the distance from the rear end of the i-th beam segment to the support point. θ i (t) represents the angle of rotation of the i-th beam segment within time t. Δν el，i (t) is the correction term caused by the elastic deformation of the main beam. Δυ nl，i (t) is the correction term for the main beam caused by the nonlinear behavior of the material.

7. The method for continuously jacking down a large-span curved steel beam according to claim 4, characterized in that, In step R350, the standard deviation of each adjustment component is calculated to determine whether the height reduction speed or angle change of each adjustment component needs to be adjusted. The standard deviation σF(t) is: Where N is the number of adjustment components. F i (t) represents the force on the i-th adjustment component. This represents the average force applied to all adjustment components. like Then it is necessary to adjust the height reduction speed or angle change of each adjustment component to make the overall force more uniform, where e is the safety factor.

8. The method for continuously jacking down a large-span curved steel beam according to claim 7, characterized in that, The adjusted height reduction speed v′ of the i-th height adjustment structure h，i (t) is: v′ h，i (t)=v h，i (t)+Δv a，i (t), Among them, υ h，i (t) represents the initial height reduction speed of the i-th height adjustment structure. Δν a，i (t) represents the adjustment amount of the height reduction speed of the i-th height adjustment structure. The height reduction speed adjustment amount Δν of the i-th height adjustment structure a，i (t) Specifically: Where, k v This is a proportional constant used to control the adjustment range. F i (t) represents the force on the i-th adjustment component. This represents the average force applied to all regulating components. The adjusted i-th angle adjustment structure's angle θ′ i (t) is: θ′ i (t)=θ i (t)+Δθ a，i (t), Where, Δθ i (t) The original angle of the structure is adjusted at the i-th angle. Δθ a，i (t) The angle adjustment amount of the i-th angle adjustment structure. The angle adjustment amount Δθ of the i-th angle adjustment structure a，i (t) Specifically: Where, k θ This is a proportional constant used to control the adjustment range. F i (t) represents the force on the i-th adjustment component. This represents the average force applied to all regulating components.

9. A method for continuously jacking down a large-span curved steel beam according to any one of claims 1-3, characterized in that, Step G400 specifically also includes: G410. After the adjustment component has finished its operation, check that the positions of each part of the main beam (2) have reached the design position and that the deviation from the design position is within the allowable error range. G420. Install permanent supports on each permanent pier (1). After the lower support plate of the permanent support is fixed to the upper surface of the permanent pier (1), remove the hinge support at the front end of the main beam (2). G430, lower all the height of the adjustment components at the same speed and slightly until all the adjustment components are no longer under force. At this time, the force of the main beam (2) is borne by the permanent support. G440, raise the height of all adjustment components at the same speed and slightly until they jointly support the main beam (2), at which point the permanent support does not bear the force of the permanent support; G450, again lower all the height of the adjustment components at the same speed and slightly until all the adjustment components are no longer under force, so that the permanent support supports the main beam (2); G460. Fix the upper support plate of the permanent support to the bottom surface of the main beam (2), remove the adjustment component and the adjustment support (8), and complete the lowering of the main beam (2).

10. A beam-lowering system for continuous jacking of large-span curved steel beams, used to implement the beam-lowering method for continuous jacking of large-span curved steel beams as described in any one of claims 1-9, characterized in that, include: The adjustment module is used to adjust the head and tail positions of the main beam (2) by adjusting the components, so that the overall position of the main beam (2) is directly above the design position and its posture is exactly the same as the design posture. The first rotating module is used to adjust the position of the main beam (2) and move it forward by one end. With the adjustment component of the last permanent pier (1) as the center, the front end of the main beam (2) is rotated downward to fall to the design position and connected to the frontmost permanent pier (1) by a hinge support. The second rotation module is used to control the adjustment component to rotate the rear end of the main beam (2) downwards with the hinge support at the frontmost permanent pier (1) as the fulcrum, until all segments of the main beam (2) fall into the design position. A fixed module is used to detect that the position of the dropped beam is correct and that there is no residual stress between the main beam (2) and all permanent piers (1). Permanent supports are installed between all permanent piers (1) and the main beam (2), and hinge supports and adjusting supports are removed.

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