A linear control method for main girder assembly in incremental launching construction

Abstract

This invention relates to the field of bridge technology and provides a method for controlling the alignment of the main beam assembly during incremental launching construction. The method involves temporarily assembling the k-th batch of beam segments at the construction site according to the calculated positioning elevation difference. When the measured elevation difference of each beam segment is less than a preset threshold, the optimal spatial positioning parameters for the temporary stress-free alignment are determined. The k-th batch of beam segments is then welded, and the incremental launching construction of the k-th batch of beam segments is carried out. If the k-th batch of beam segments is not the last batch, the measured elevation difference of the tail beam of the last beam segment of the k-th batch is obtained. The calculated positioning elevation difference of the first beam segment of the k+1-th batch and the calculated positioning elevation difference of the remaining beam segments are then determined. This application achieves high-precision alignment control of the main beam during multi-round incremental launching construction by controlling the assembly error of each batch and guiding the assembly construction of the next batch by correcting the actual end state after the previous batch's incremental launching.

Description

Technical Field

[0001] This invention relates to the field of bridge technology, and in particular to a method for controlling the alignment of the main beam during incremental launching construction. Background Technology

[0002] Incremental launching is an important construction method for long-span bridges. It involves segmented, cyclical operations, with alignment control being crucial. In incremental launching, the main girder is assembled sequentially on the launching platform. After each batch of girder segments is assembled, it is moved forward to a designated position using the launching equipment, reserving space for the next batch. The assembly and welding of the next batch of segments then continues. This process is repeated until the entire main girder assembly is complete. Throughout this process, the spatial position of the assembled girder segments changes continuously, but their stress-free alignment remains constant; that is, the geometric parameters are fixed, only the spatial positioning parameters change.

[0003] The current conventional method for controlling beam alignment is to ensure that the actual stress-free angle between each batch of newly assembled beam segments matches the theoretical stress-free angle. This traditional method primarily controls errors through on-site positioning to minimize assembly errors, but it fails to correct for alignment errors (such as local elevation deviations) at each stage. These errors are transmitted to subsequent stages through beam stiffness, forming an "error chain," which can amplify into overall alignment loss of control in severe cases. This problem becomes even more pronounced in multi-round jacking operations.

[0004] Therefore, it is necessary to propose a method for controlling the alignment of the main beam assembly during incremental launching to solve or at least alleviate the above-mentioned defects. Summary of the Invention

[0005] The main objective of this invention is to provide a method for controlling the alignment of the main beam during incremental launching construction, in order to solve the technical problem that the existing technology fails to correct the phased alignment errors, which leads to the easy loss of control over the overall bridge alignment error after incremental launching construction.

[0006] To achieve the above objectives, the present invention provides a method for controlling the alignment of the main beam assembly during jacking construction, comprising the following steps:

[0007] S1, obtain the calculated positioning height difference of each beam segment in the kth batch of beam segments before temporary assembly; where k is a positive integer and the initial value of k is 1;

[0008] S2, At the construction site, the kth batch of beam segments are temporarily assembled according to the calculated positioning height difference, and the measured value of the beam segment height difference of each beam segment after temporary assembly is obtained. When the measured value of the beam segment height difference of each beam segment is less than the preset threshold, the temporary assembly angle of the splicing node formed by two adjacent beam segments is obtained according to the measured value of the beam segment height difference.

[0009] S3, determine the temporary stress-free shape of the kth batch of beam segments after temporary assembly based on the temporary assembly angle and obtain the theoretical stress-free shape, and determine the optimal spatial positioning parameters of the temporary stress-free shape according to minimizing the deviation between the temporary stress-free shape and the theoretical stress-free shape; wherein, the optimal spatial positioning parameters include the optimal elevation value and the optimal forward included angle of the last splicing node of the temporary stress-free shape;

[0010] S4, determine the stress-free included angle calculation value of the first beam segment of the (k+1)th batch of beam segments according to the optimal spatial positioning parameters;

[0011] S5, Welding is carried out on the kth batch of beam segments, followed by the jacking operation of the kth batch of beam segments, and they are jacked into place according to the predetermined requirements;

[0012] S6, determine whether the kth batch of beam segments is the last batch of beam segments. If yes, determine that the entire bridge has been pushed into place. If not, obtain the measured value of the tail beam height difference of the last beam segment of the kth batch of beam segments. Based on the measured value of the tail beam height difference and the calculated value of the stress-free angle, determine the calculated value of the positioning height difference of the first beam segment of the k+1th batch of beam segments. Determine the calculated value of the positioning height difference of the remaining beam segments in the k+1th batch of beam segments. Then assign k+1 to k and return to step S2.

[0013] Preferably, when k is 1, step S1 includes the following steps:

[0014] S11, First determine the number of beam segments in the first batch. And according to the number of beam segments The number of splicing nodes is obtained as follows +1; where the number of beam segments is... and the number of splicing nodes The numbering order of +1 is opposite to the pushing direction, and the splicing node numbering is from 1 to... +1, the beam segment number corresponds to 1 to... ;

[0015] S12, using formula Obtain the calculated positioning elevation difference of the first beam segment in the first batch of beam segments. ;in, This is the theoretical elevation value of the first splicing node. This is the theoretical elevation value of the second splicing node. This represents the theoretical elevation difference between the two ends of the first beam segment;

[0016] S13, using formula Obtain the calculated positional elevation difference of the (i+1)th beam segment. Where i≤ , Let i be the length of the (i+1)th beam segment. Let be the calculated elevation difference of the i-th beam segment. Let be the length of the i-th beam segment. This is the calculated value of the stress-free included angle at the (i+1)th splicing node before splicing the first batch of beam segments, where... = , This is the theoretical value of the stress-free included angle at the (i+1)th splicing node of the first batch of beam segments;

[0017] S14, sequentially set i to 1 to... Substituting -1 into the formula in step S13, we obtain the second beam segment to the... Calculated elevation difference of each beam segment before temporary assembly.

[0018] Preferably, when k is not 1, step S1 includes the following steps:

[0019] S100, first determine the number of beam segments in the kth batch. And according to the number of beam segments The number of newly added splicing nodes is: Among them, the number of beam segments and the number of newly added splicing nodes The numbering order is opposite to the jacking direction, and the splicing node numbers are from ni+2 to ni+ +1, the beam segment numbering corresponds to ni+1 to ni+ ni represents the number of beam segments that have been assembled;

[0020] S101, using formula Obtain the calculated positional elevation difference of the j-th beam segment in the k-th batch of beam segments. Where, j≤ , Let j be the length of the j-th beam segment in the k-th batch of beam segments. This is the calculated elevation difference of the (j-1)th beam segment in the k-th batch of beam segments. Let J be the length of the (j-1)th beam segment in the k-th batch of beam segments. Before the splicing of the kth batch of beam segments, in the first Calculated values ​​of the stress-free included angle at each splicing node;

[0021] S102, sequentially change j from 2 to... Substituting into the formula in step S101, we obtain the second beam segment to the third beam segment in the kth batch. Calculated value of the positioning elevation difference of each beam segment.

[0022] Preferably, when k is 1, the temporary assembly angle of the splicing node formed by two adjacent beam segments in step S2, based on the measured value of the beam segment height difference, includes the following steps:

[0023] S21, using formula Obtain the temporary assembly angle at the (i+1)th splicing node before splicing the first batch of beam segments. ;in, This represents the measured elevation difference of the i-th beam segment in the first batch of beam segments. This refers to the measured elevation difference of the (i+1)th beam segment in the first batch of beam segments;

[0024] S22, sequentially set i to 1 to... Substituting -1 into the formula in step S21, we obtain the second splicing node up to the... Temporary assembly angle of each splicing node.

[0025] Preferably, when k is 1, the step S3 of determining the optimal spatial positioning parameters of the temporary stress-free alignment according to minimizing the deviation between the temporary stress-free alignment and the theoretical stress-free alignment includes the following steps: according to minimizing the deviation between the temporary stress-free alignment and the theoretical stress-free alignment, solving for the optimal elevation value and the optimal forward angle of the last splicing node of the temporary stress-free alignment in the first batch of beam segments, and using the optimal elevation value and the optimal forward angle as the optimal spatial positioning parameters.

[0026] Preferably, step S4 includes the following steps:

[0027] Using formula = + Determine the calculated value of the stress-free included angle for the first beam segment of the (k+1)th batch of beam segments. ;in, The optimal forward angle is... The optimal elevation value is... For the first Theoretical elevation values ​​at each splicing node. For the first The length of each beam segment.

[0028] Preferably, the preset threshold in step S2 is set between 2mm and 5mm.

[0029] Preferably, the number of beam segments in each batch is set between 1 and 10.

[0030] Compared with the prior art, the present invention has the following beneficial effects:

[0031] This invention provides a method for controlling the alignment of the main beam assembly during jacking construction. The method involves temporarily assembling the k-th batch of beam segments at the construction site according to the calculated positioning elevation difference. When the measured elevation difference of each beam segment is less than a preset threshold, the optimal spatial positioning parameters for the temporary stress-free alignment are determined. Welding is then performed on the k-th batch of beam segments, followed by jacking construction. If the k-th batch of beam segments is not the last batch, the measured elevation difference of the tail beam of the last segment of the k-th batch is obtained. The calculated positioning elevation difference of the first segment of the (k+1)-th batch of beam segments is then determined, along with the calculated positioning elevation differences of the remaining segments in the (k+1)-th batch.

[0032] This application achieves high-precision alignment control of the main beam during multi-round jacking construction by controlling the assembly error of each batch and determining the stress-free angle and positioning height difference of the beam segments to be assembled. It also uses the actual end state after the previous batch's jacking to guide the assembly of the next batch, thus realizing timely correction of phased alignment errors. This application has a clear concept and high precision, and can provide theoretical support and technical reference for similar projects. Attached Figure Description

[0033] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on the structures shown in these drawings without creative effort.

[0034] Figure 1 This is a schematic diagram of a process in one embodiment of the present invention;

[0035] Figure 2 This is a schematic diagram illustrating the stress-free linear parameters of a beam in one embodiment of the present invention.

[0036] The objectives, features, and advantages of this invention will be further explained in conjunction with the embodiments and with reference to the accompanying drawings. Detailed Implementation

[0037] It should be understood that the specific embodiments described herein are merely illustrative of the invention and are not intended to limit the invention.

[0038] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only a part of the embodiments of the present invention, and not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the scope of protection of the present invention.

[0039] In this invention, the terms "first," "second," etc., are used for descriptive purposes only and should not be construed as indicating or implying their relative importance or implicitly specifying the number of technical features indicated. Therefore, a feature defined as "first" or "second" may explicitly or implicitly include at least one of that feature. Furthermore, the technical solutions of the various embodiments can be combined with each other, but only on the basis of being achievable by those skilled in the art. If the combination of technical solutions is contradictory or impossible to implement, it should be considered that such a combination of technical solutions does not exist and is not within the scope of protection claimed by this invention.

[0040] Those skilled in the art will understand that controlling the stress-free alignment of the beam is crucial during incremental launching construction. To systematically analyze and control the stress-free alignment, this application introduces two types of alignment description parameters: geometric configuration parameters and spatial positioning parameters. These two types of parameters describe the characteristics of the stress-free alignment from different perspectives, providing a theoretical basis for subsequent alignment analysis and control.

[0041] (1) Geometric configuration parameters: Geometric configuration parameters mainly describe the shape characteristics of the stress-free line and are independent of the specific coordinate system. These parameters determine the geometry of the line and are the core elements of line control. Specifically, they are the beam segment length and the stress-free angle.

[0042] (2) Spatial positioning parameters: Spatial positioning parameters describe the specific location of the stress-free alignment in space. These parameters, combined with geometric configuration parameters, can completely define the stress-free alignment. Spatial positioning parameters include: mileage coordinates of nodes, elevation coordinates, elevation difference between the two ends of the beam segment, forward angle of the alignment, and backward angle of the alignment, etc.

[0043] After introducing the two types of parameters for the stress-free alignment of the beam, the following section describes the specific parameters of the stress-free alignment of the beam in light of the actual conditions of the jacking construction.

[0044] like Figure 2 As shown, if the number of beam segments that make up the jacking beam is n, then the number of splicing nodes between the beam segments is n+1; the numbering order is opposite to the jacking direction, and the node numbers are from 1 to n+1, while the beam segment numbers are from 1 to n. (i=1, 2, ..., n+1) represents the mileage coordinates of the i-th splicing node. Let be the elevation coordinates of the i-th splicing node; (i=1,2,…,n) represents the beam length of the i-th beam segment. This represents the height difference between the two ends of the i-th beam segment. (i=2,3,...,n) is the stress-free angle of the linear shape at the i-th splicing node; (i=1,2,...,n) represents the backward angle of the line at the i-th splicing node, that is, the angle between the i-th beam segment and the vertical line at the i-th splicing node. (i=2,3,...,n+1) represents the forward angle of the line at the i-th splicing node, that is, the angle between the (i-1)-th beam segment and the vertical line at the i-th splicing node.

[0045] Among the parameters mentioned above, The geometric configuration parameters of the stress-free linear shape are determined by the geometry of the linear shape. , , , , The spatial positioning parameters of a line shape are determined by its specific location in space.

[0046] As described above, this application has defined the descriptive parameters of the linear shape. Next, it introduces methods for representing the linear shape. Two methods for representing stress-free linear shapes will be introduced below: coordinate representation and geometric configuration representation, and the transformation formulas between these two methods will be derived.

[0047] (1) Coordinate representation

[0048] Coordinate representation is an intuitive, stress-free method for describing line shapes, which defines the line shape directly through the coordinates of the nodes:

[0049] = ( ，...， );

[0050] The advantage of coordinate representation is that it allows for intuitive analysis of the deviation between two lines within the same coordinate system. However, this method cannot directly reflect the geometric characteristics of the lines and is inconvenient for coordinate transformations.

[0051] (2) Geometric configuration representation

[0052] To more flexibly describe the geometric characteristics of stress-free alignments, a geometric configuration representation is introduced. This representation defines the alignment using geometric configuration parameters and spatial positioning parameters. Specifically, for a stress-free beam segment alignment as described above, with n+1 splice nodes and 2n+2 degrees of freedom, the geometric configuration representation selects all 2n-1 geometric configuration parameters included in the description and chooses the three necessary spatial positioning parameters for representation:

[0053] = ( ...， );

[0054] = );

[0055] in Spatial positioning parameters determine the specific location of the line in space. The geometric configuration parameters determine the geometric configuration of the line. The advantage of the geometric configuration representation method lies in its clear characterization of the geometric features of the line and its convenience in the coordinate transformation process, which is very beneficial for the control analysis and calculation of stress-free lines.

[0056] (3) Transformation formula between coordinate representation and geometric representation

[0057] To facilitate flexible conversion between the two representation methods, it is necessary to establish the mathematical transformation relationship between them. The conversion from coordinate representation to geometric representation is relatively intuitive; geometric parameters can be directly calculated through geometric relationships, which will not be elaborated upon here. This application focuses on the derivation of the elevation formula from geometric representation to coordinate representation. The derivation process is as follows:

[0058] According to geometric relations, we have:

[0059] = ; + =

[0060] Furthermore, through mathematical derivation, we obtain:

[0061] ;

[0062] ;

[0063] Equation (1);

[0064] Where k, m, and q represent the difference between the index number of the current calculation variable and n+1, and k takes the value of (1, 2, ..., n); Equation (1) is the coordinate transformation formula for elevation, and it can be seen from the formula that (i takes the values ​​1, 2, ..., n) is The function of ).

[0065] It is also worth noting that the beam segment length parameter is (i=1, 2, ..., n), the beam segment length hardly changes during the actual assembly process, so it is assumed that the beam segment length remains constant, that is, the deviation of the beam length is not considered; the elevation parameters of n+1 splicing nodes ( ... The superscript N represents the theoretical linear parameter, which can be obtained directly using software such as Midas.

[0066] Please see the appendix Figures 1 to 2 The present invention provides a method for controlling the alignment of the main beam assembly during jacking construction, comprising the following steps:

[0067] S1, obtain the calculated positioning height difference of each beam segment in the kth batch of beam segments before temporary assembly; where k is a positive integer and the initial value of k is 1;

[0068] To quantify the jacking construction of each batch, this application introduces a variable k. When k is 1, the first batch of beam segments is constructed first; when k is 2, the second batch of beam segments is constructed, and so on, until all batches of beam segments are constructed. The calculated positioning elevation difference is used as the temporary assembly command value for the corresponding beam segment. During subsequent temporary assembly, temporary layout control is performed according to the corresponding calculated positioning elevation difference value to ensure the accuracy of the temporary assembly stage.

[0069] S2, At the construction site, the kth batch of beam segments are temporarily assembled according to the calculated positioning height difference, and the measured value of the beam segment height difference of each beam segment after temporary assembly is obtained. When the measured value of the beam segment height difference of each beam segment is less than the preset threshold, the temporary assembly angle of the splicing node formed by two adjacent beam segments is obtained according to the measured value of the beam segment height difference.

[0070] At the construction site, based on the calculated elevation difference of S1, the kth batch of beam segments is temporarily assembled. The actual elevation difference of each temporarily assembled beam segment is measured. Existing technology can be used for measurement, which will not be elaborated here. Only when the actual elevation difference of all beam segments in the kth batch is less than a preset threshold will the next step be performed to ensure the accuracy requirements of the temporary assembly. If the actual elevation difference of a beam segment is greater than or equal to the preset threshold, the beam segment is readjusted and reassembled. For each splicing node formed by adjacent beam segments, the actual angle (temporary assembly angle) of each splicing node in the temporary assembly state is calculated based on the actual elevation difference of the beam segments.

[0071] S3, determine the temporary stress-free shape of the kth batch of beam segments after temporary assembly based on the temporary assembly angle and obtain the theoretical stress-free shape, and determine the optimal spatial positioning parameters of the temporary stress-free shape according to minimizing the deviation between the temporary stress-free shape and the theoretical stress-free shape; wherein, the optimal spatial positioning parameters include the optimal elevation value and the optimal forward included angle of the last splicing node of the temporary stress-free shape;

[0072] Specifically, as can be seen from the above, The geometric configuration parameters determine the geometric configuration of the alignment. Therefore, by obtaining the temporary assembly angle and combining it with the beam segment length, the temporary stress-free alignment of the kth batch of beam segments after temporary assembly can be obtained. It should be noted that due to possible errors in the assembly process or the influence of construction errors in the previous jacking process, there will be a deviation between the temporary stress-free alignment and the theoretical stress-free alignment (target ideal alignment).

[0073] This application determines the optimal spatial positioning parameters of the temporary stress-free alignment by minimizing the deviation between the temporary stress-free alignment and the theoretical stress-free alignment. Specifically, this application finds a set of optimal spatial positioning parameters that minimize the overall deviation between the calculated temporary stress-free alignment and the theoretical stress-free alignment. These optimal spatial positioning parameters can be used to guide the construction of the next batch of beam segments, that is, to correct stage-specific alignment errors in a timely manner, thereby improving the accuracy of alignment control. Furthermore, in conjunction with the above-described: (i takes the values ​​1, 2, ..., n) is The function of ) temporary assembly angle The beam segment length can be obtained through step S2. It is known that the optimal spatial positioning parameters include the optimal elevation and optimal forward angle of the last splicing node of the temporary stress-free alignment. Therefore, the positioning elevation difference of the first beam in the next batch can be calculated, which will be discussed later.

[0074] Step S3, obtaining the theoretical stress-free profile, specifically includes the following steps: A planar bar element model of the beam segment is established using Midas software. Simulation analysis is performed according to the planned construction sequence. The cumulative deflection value during the entire launching construction process and 10 years after the bridge completion is added to half of the live load deflection effect, and then inverted. This result is the manufacturing precamber of the beam segment. The theoretical stress-free profile (also called the manufacturing profile) is the sum of the design elevation of the beam segment and the manufacturing precamber. This part is mature technology and will not be elaborated upon here.

[0075] S4, determine the stress-free included angle calculation value of the first beam segment of the (k+1)th batch of beam segments according to the optimal spatial positioning parameters;

[0076] The stress-free angle of the first beam segment in the next batch is calculated based on the optimal spatial positioning parameters, and is used to determine the positioning height difference of the first beam segment in the (k+1)th batch.

[0077] S5. Welding is performed on the k-th batch of beam segments, followed by jacking the k-th batch of beam segments into place according to predetermined requirements. After the measured height difference of each beam segment is less than a preset threshold, the beam segments in this batch are welded and fixed, and then the jacking of the k-th batch of beam segments is performed again, jacking them into place according to predetermined requirements, thus making room for the assembly of the next batch of beam segments. It should be noted that welding the k-th batch of beam segments is to promptly fix the spatial position of the temporarily assembled k-th batch of beam segments. In other embodiments, other methods can also be used to promptly fix the spatial position of the temporarily assembled k-th batch of beam segments.

[0078] S6, determine whether the kth batch of beam segments is the last batch of beam segments. If yes, determine that the entire bridge has been pushed into place. If not, obtain the measured value of the tail beam height difference of the last beam segment of the kth batch of beam segments. Based on the measured value of the tail beam height difference and the calculated value of the stress-free angle, determine the calculated value of the positioning height difference of the first beam segment of the k+1th batch of beam segments. Determine the calculated value of the positioning height difference of the remaining beam segments in the k+1th batch of beam segments. Then assign k+1 to k and return to step S2.

[0079] After the jacking is completed, the spatial position of the beam segments will change during the jacking process. Therefore, the actual elevation deviation of the last beam segment of the kth batch is measured. Based on the measured value of the tail beam elevation difference obtained at this time and the calculated value of the stress-free included angle of the first beam segment of the k+1th batch calculated in step S4, the calculated value of the positioning elevation difference of the first beam segment of the k+1th batch is determined. After determining the calculated value of the positioning elevation difference of the first beam segment of the k+1th batch, the calculated value of the positioning elevation difference of the remaining beam segments in the k+1th batch can be determined. Then, return to step S2 to carry out the temporary assembly construction of the k+1th batch. This application guides the assembly construction of the next batch by correcting the actual end state after the jacking of the previous batch, that is, timely correction of the staged alignment error, thereby improving the alignment control accuracy.

[0080] In this application, by controlling the assembly error of each batch and determining the stress-free angle and positioning height difference of the beam segments to be assembled, the actual end state after the previous batch's jacking is used to guide the assembly of the next batch, thus achieving timely correction of phased alignment errors. This enables high-precision alignment control of the main beam during multiple rounds of jacking construction. This application has a clear concept and high precision, and can provide theoretical support and technical reference for similar projects.

[0081] In a preferred embodiment, when k is 1, step S1 includes the following steps:

[0082] S11, First determine the number of beam segments in the first batch. And according to the number of beam segments The number of splicing nodes is obtained as follows +1; where the number of beam segments is... and the number of splicing nodes The numbering order of +1 is opposite to the pushing direction, and the splicing node numbering is from 1 to... +1, the beam segment number corresponds to 1 to... ;

[0083] S12, using formula Obtain the calculated positioning elevation difference of the first beam segment in the first batch of beam segments. ;in, This is the theoretical elevation value of the first splicing node. This is the theoretical elevation value of the second splicing node. This is the theoretical elevation difference between the two ends of the first beam segment, that is, the difference in theoretical elevation values ​​between the two splicing nodes at both ends of the beam segment;

[0084] S13, using formula Obtain the calculated positional elevation difference of the (i+1)th beam segment. Where i≤ , Let i be the length of the (i+1)th beam segment. Let be the calculated elevation difference of the i-th beam segment. Let be the length of the i-th beam segment. This is the calculated value of the stress-free included angle at the (i+1)th splicing node before splicing the first batch of beam segments, where... = , This is the theoretical value of the stress-free included angle at the (i+1)th splicing node of the first batch of beam segments;

[0085] It should be noted that, as discussed above, the stress-free angle in the geometric configuration parameters is independent of the specific coordinate system. The calculated value of the stress-free angle at the (i+1)th splicing node before splicing the first batch of beam segments is... The theoretical value of the stress-free angle between the first batch of beam segments and the (i+1)th splice node. The values ​​are equal, and the value is calculated using the stress-free angle. This allows us to further determine the calculated positioning height difference of each beam segment before temporary assembly.

[0086] S14, sequentially set i to 1 to... Substituting -1 into the formula in step S13, we obtain the second beam segment to the... Calculated elevation difference of each beam segment before temporary assembly.

[0087] In a preferred embodiment, when k is not 1, step S1 includes the following steps:

[0088] S100, first determine the number of beam segments in the kth batch. And according to the number of beam segments The number of newly added splicing nodes is: Among them, the number of beam segments and the number of newly added splicing nodes The numbering order is opposite to the jacking direction, and the splicing node numbers are from ni+2 to ni+ +1, the beam segment numbering corresponds to ni+1 to ni+ ni represents the number of beam segments that have been assembled;

[0089] For example, the number of beam segments in the second batch. The splice joints between the first segment of the second batch of beams and the last segment of the first batch of beams are not counted repeatedly in the splice joints of the second batch of beams. Therefore, the construction of the second batch of beams will result in an additional number of splice joints. ;

[0090] S101, using formula Obtain the calculated positional elevation difference of the j-th beam segment in the k-th batch of beam segments. Where, j≤ , Let j be the length of the j-th beam segment in the k-th batch of beam segments. This is the calculated elevation difference of the (j-1)th beam segment in the k-th batch of beam segments. Let J be the length of the (j-1)th beam segment in the k-th batch of beam segments. Before the splicing of the kth batch of beam segments, in the first Calculated values ​​of the stress-free included angle at each splicing node;

[0091] S102, sequentially change j from 2 to... Substituting into the formula in step S101, we obtain the second beam segment to the third beam segment in the kth batch. Calculated value of the positioning elevation difference of each beam segment.

[0092] It should be noted that when k is not 1, the j-th beam segment in the k-th batch of beam segments does not need to be calculated for the first beam segment in the k-th batch of beam segments. The positioning elevation difference of the first beam segment in the k-th batch of beam segments can be calculated in step S6 by successively setting j to 2 to 1. Substituting into the formula in step S101, we obtain the second beam segment to the third beam segment in the kth batch. Calculated value of the positioning elevation difference of each beam segment.

[0093] As a preferred embodiment, when k is 1, the step S2 of obtaining the temporary assembly angle of the splicing node formed by two adjacent beam segments based on the measured value of the beam segment height difference includes the following steps:

[0094] S21, using formula Obtain the temporary assembly angle at the (i+1)th splicing node before splicing the first batch of beam segments. ;in, This represents the measured elevation difference of the i-th beam segment in the first batch of beam segments. This refers to the measured elevation difference of the (i+1)th beam segment in the first batch of beam segments;

[0095] S22, sequentially set i to 1 to... Substituting -1 into the formula in step S21, we obtain the second splicing node up to the... Temporary assembly angle of each splicing node.

[0096] When k is not 1, the temporary assembly angle at the (i+1)th splicing node before splicing the kth batch of beam segments can also be obtained by referring to the formula in step S21.

[0097] Furthermore, when k is 1, the step S3 of determining the optimal spatial positioning parameters of the temporary stress-free alignment according to minimizing the deviation between the temporary stress-free alignment and the theoretical stress-free alignment includes the following steps: according to minimizing the deviation between the temporary stress-free alignment and the theoretical stress-free alignment, solve for the optimal elevation value and the optimal forward angle of the last splicing node of the temporary stress-free alignment in the first batch of beam segments, and use the optimal elevation value and the optimal forward angle as the optimal spatial positioning parameters.

[0098] When k is not 1, the optimal elevation and optimal forward angle of the last splicing node of the temporary stress-free alignment in the first batch of beam segments can be solved by minimizing the deviation between the temporary stress-free alignment and the theoretical stress-free alignment, and the optimal elevation and the optimal forward angle can be used as the optimal spatial positioning parameters.

[0099] As a specific example, in order to solve for the optimal spatial positioning parameters of the stress-free profile of the beam, it is necessary to first quantify the deviation between the temporary stress-free profile and the theoretical stress-free profile.

[0100] In the alignment parameter calibration during incremental launching construction, the theoretical stress-free alignment is defined as the calibration target alignment, while the actual, assembled temporary stress-free alignment is used as the calibration alignment. To quantify the deviation between these two alignments, the following definition is used: The deviation between the two alignments within a given interval... The function on is and For example, a temporary stress-free linear shape is The theoretical stress-free linear shape is ,deviation Defined as:

[0101] ;

[0102] Although the formula is accurate, the integral calculation is quite complex, making it inconvenient for practical applications.

[0103] For linearity expressed in discrete points = ( ，...， )and = ( ，...， We can simplify the deviation calculation formula as follows:

[0104] Equation (2)

[0105] This simplified formula is more convenient in actual calculations and can better reflect the differences between the two lines.

[0106] In the actual launching calculation process, it is assumed that the temporary stress-free line of the first i assembled beam segments is as follows: =F ( The corresponding theoretical stress-free linear shape is = ( ... The superscript N indicates the theoretical value, and X indicates the measured value. Temporary stress-free line. The elevation coordinates obtained after transforming the coordinates to the theoretical coordinate system according to equation (1) Only variable space location parameters , The function. Solving for the optimal spatial positioning parameters is equivalent to finding the parameters. , Make the linear deviation value Minimum.

[0107] Solve the system of equations:

[0108] ;

[0109] ;

[0110] The variable value corresponding to the minimum linear deviation can be obtained. That is, linear Matching Linear The optimal spatial positioning parameters. At this point... This is called the optimal calibration line shape.

[0111] This embodiment constructs a geometric configuration representation method for stress-free linear shapes and establishes a quantitative formula for linear deviation, deriving a calculation method for optimal spatial positioning parameters, aiming to minimize the deviation between the assembled stress-free linear shape and the theoretical stress-free linear shape.

[0112] Preferably, step S4 includes the following steps:

[0113] Using formula = + Determine the calculated value of the stress-free included angle for the first beam segment of the (k+1)th batch of beam segments. ;in, The optimal forward angle is... The optimal elevation value is... For the first Theoretical elevation values ​​at each splicing node. For the first The length of each beam segment.

[0114] Based on the above discussion, Replace with , Replace with This allows us to obtain the calculated value of the stress-free included angle of the first beam segment in the (k+1)th batch of beam segments. . For the first The theoretical elevation value at each splice node, that is, the theoretical elevation value of the first splice node of the next batch of beam segments. For the first The length of a beam segment, that is, the length of the first beam segment in the next batch of beam segments.

[0115] As a preferred example, the preset threshold in step S2 is set between 2mm and 5mm, and the number of beam segments in each batch is set between 1 and 10. In other embodiments, the preset threshold and the number of beam segments can be set according to actual needs.

[0116] The above are merely preferred embodiments of the present invention and do not limit the scope of protection of the present invention. Any equivalent structural or procedural transformations made based on the content of the present invention’s specification and drawings, or direct or indirect applications in other related technical fields, are similarly included within the scope of patent protection of the present invention.

Claims

1. A method for controlling the alignment of the main beam assembly during incremental launching construction, characterized in that, Includes the following steps: S1, obtain the calculated positioning height difference of each beam segment in the kth batch of beam segments before temporary assembly; where k is a positive integer and the initial value of k is 1; S2, At the construction site, the kth batch of beam segments are temporarily assembled according to the calculated positioning height difference, and the measured value of the beam segment height difference of each beam segment after temporary assembly is obtained. When the measured value of the beam segment height difference of each beam segment is less than the preset threshold, the temporary assembly angle of the splicing node formed by two adjacent beam segments is obtained according to the measured value of the beam segment height difference. S3, determine the temporary stress-free shape of the kth batch of beam segments after temporary assembly based on the temporary assembly angle and obtain the theoretical stress-free shape, and determine the optimal spatial positioning parameters of the temporary stress-free shape according to minimizing the deviation between the temporary stress-free shape and the theoretical stress-free shape; wherein, the optimal spatial positioning parameters include the optimal elevation value and the optimal forward included angle of the last splicing node of the temporary stress-free shape; S4, determine the stress-free included angle calculation value of the first beam segment of the (k+1)th batch of beam segments according to the optimal spatial positioning parameters; S5, Welding is carried out on the kth batch of beam segments, followed by the jacking operation of the kth batch of beam segments, and they are jacked into place according to the predetermined requirements; S6, determine whether the kth batch of beam segments is the last batch of beam segments. If yes, determine that the entire bridge has been pushed into place. If not, obtain the measured value of the tail beam height difference of the last beam segment of the kth batch of beam segments. Based on the measured value of the tail beam height difference and the calculated value of the stress-free angle, determine the calculated value of the positioning height difference of the first beam segment of the k+1th batch of beam segments. Determine the calculated value of the positioning height difference of the remaining beam segments in the k+1th batch of beam segments. Then assign k+1 to k and return to step S2. Step S4 includes the following steps: Using formula = + Determine the calculated value of the stress-free included angle for the first beam segment of the (k+1)th batch of beam segments. ;in, The optimal forward angle is... The optimal elevation value is... For the first Theoretical elevation values ​​at each splicing node. For the first The length of each beam segment.

2. The method for controlling the alignment of the main beam assembly during incremental launching construction according to claim 1, characterized in that, When k is 1, step S1 includes the following steps: S11, First determine the number of beam segments in the first batch. And according to the number of beam segments The number of splicing nodes is obtained as follows +1; where the number of beam segments is... and the number of splicing nodes The numbering order of +1 is opposite to the pushing direction, and the splicing node numbering is from 1 to... +1, the beam segment number corresponds to 1 to... ; S12, using formula Obtain the calculated positioning elevation difference of the first beam segment in the first batch of beam segments. ;in, This is the theoretical elevation value of the first splicing node. This is the theoretical elevation value of the second splicing node. This represents the theoretical elevation difference between the two ends of the first beam segment; S13, using formula Obtain the calculated positional elevation difference of the (i+1)th beam segment. Where i≤ , Let be the length of the (i+1)th beam segment. Let be the calculated elevation difference of the i-th beam segment. Let be the length of the i-th beam segment. This is the calculated value of the stress-free included angle at the (i+1)th splicing node before splicing the first batch of beam segments, where... = , This is the theoretical value of the stress-free included angle at the (i+1)th splicing node of the first batch of beam segments; S14, sequentially set i to 1 to... Substituting -1 into the formula in step S13, we obtain the second beam segment to the... Calculated elevation difference of each beam segment before temporary assembly.

3. The method for controlling the alignment of the main beam assembly during incremental launching construction according to claim 2, characterized in that, When k is not 1, step S1 includes the following steps: S100, first determine the number of beam segments in the kth batch. And according to the number of beam segments The number of newly added splicing nodes is: Among them, the number of beam segments and the number of newly added splicing nodes The numbering order is opposite to the jacking direction, and the splicing node numbers are from ni+2 to ni+ +1, the beam segment numbering corresponds to ni+1 to ni+ ni represents the number of beam segments that have been assembled; S101, using formula Obtain the calculated positional elevation difference of the j-th beam segment in the k-th batch of beam segments. Where, j≤ , Let j be the length of the j-th beam segment in the k-th batch of beam segments. This is the calculated elevation difference of the (j-1)th beam segment in the k-th batch of beam segments. Let J be the length of the (j-1)th beam segment in the k-th batch of beam segments. Before the splicing of the kth batch of beam segments, in the first Calculated values ​​of the stress-free included angle at each splicing node; S102, sequentially change j from 2 to... Substituting into the formula in step S101, we obtain the second beam segment to the third beam segment in the kth batch. Calculated value of the positioning elevation difference of each beam segment.

4. The method for controlling the alignment of the main beam assembly during incremental launching construction according to claim 2, characterized in that, When k is 1, the temporary assembly angle of the splicing node formed by two adjacent beam segments in step S2, based on the measured value of the beam segment height difference, includes the following steps: S21, using formula Obtain the temporary assembly angle at the (i+1)th splicing node before splicing the first batch of beam segments. ;in, This represents the measured elevation difference of the i-th beam segment in the first batch of beam segments. This refers to the measured elevation difference of the (i+1)th beam segment in the first batch of beam segments; S22, sequentially set i to 1 to... Substituting -1 into the formula in step S21, we obtain the second splicing node up to the... Temporary assembly angle of each splicing node.

5. The method for controlling the alignment of the main beam assembly during incremental launching construction according to claim 4, characterized in that, When k is 1, the step S3 of determining the optimal spatial positioning parameters of the temporary stress-free shape by minimizing the deviation between the temporary stress-free shape and the theoretical stress-free shape includes the following steps: Based on minimizing the deviation between the temporary stress-free alignment and the theoretical stress-free alignment, the optimal elevation value and optimal forward angle of the last splicing node of the temporary stress-free alignment in the first batch of beam segments are calculated, and the optimal elevation value and the optimal forward angle are used as the optimal spatial positioning parameters.

6. The method for controlling the alignment of the main beam assembly during incremental launching construction according to claim 2, characterized in that, The preset threshold in step S2 is set between 2mm and 5mm.

7. The method for controlling the alignment of the main beam assembly during incremental launching construction according to claim 1, characterized in that, The number of beam segments in each batch is set between 1 and 10.

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