A method for adjusting and optimizing construction posture of a small-radius curve large-slope narrow bridge

Abstract

This invention relates to the field of construction posture optimization technology, and particularly to a method for optimizing the construction posture of a narrow-span bridge with a small radius curve and steep slope. The method includes: establishing a construction posture control model based on initial erection parameters; inputting the geometric design parameters of the target bridge section into the construction posture control model and outputting the initial erection path, outrigger adjustment method, and predicted deviation parameters; collecting the erection deviation parameters; determining the posture correction method based on the deviation between the erection deviation parameters and the predicted deviation parameters, including adjusting the bridge erecting machine's steering coefficient, outrigger support force distribution, and lateral movement speed; when the deviation continuously exceeds a preset threshold, implementing a graded early warning method, including inserting an intermediate stable working condition or recalculating the optimal posture erection adjustment path; and continuing the erection of the span and beam according to the optimal posture erection adjustment path to complete the beam positioning. This invention improves erection accuracy and operational stability.

Description

Technical Field

[0001] This invention relates to the field of construction posture optimization technology, and in particular to a method for adjusting and optimizing the construction posture of a narrow-span bridge with a small radius curve and steep slope. Background Technology

[0002] In existing technologies, bridge erecting machines have wide applicability and are suitable for various bridge types and construction scenarios. Especially in environments with complex terrain, medium spans, and limited construction space, their efficiency, safety, and flexibility make them important equipment in modern bridge construction, particularly in large-scale infrastructure projects such as highways, railways, and urban viaducts. In Abu Dhabi, UAE, bridge construction and prefabrication often use large crawler cranes for shore-side hoisting, with crane tonnage typically exceeding 1000 tons. Therefore, the design did not consider the bridge erecting machine's beam erection conditions. To verify whether using a bridge erecting machine for beam erection is suitable for local bridge structures, it is necessary to conduct stress calculation and analysis on the main bridge structure under the bridge erecting machine's beam erection conditions and generate a report. In bridge construction, the construction of small-radius curved, steep, and narrow-span bridges is relatively complex, especially in the beam erection stage. This is because the alignment design of curved bridges places higher demands on the adaptability of bridge erecting machines. The construction challenges of small-radius curved, steep, and narrow-span bridges mainly lie in the small turning radius and the special requirements for beam span. Therefore, research on the construction technology of bridge erecting machines in the span of narrow bridges with small radius curves, steep slopes, and narrow spans, i.e., the erection of beams across spans, is of great significance for improving engineering efficiency and safety.

[0003] Chinese Patent Publication No. CN116949946A discloses a method for constructing a small-radius curved bridge, including: Step 1: Using a double-guide beam bridge erection machine to install the beams. First, adjust the bridge erection machine by adding a flange with degrees of freedom and a rotating shaft to the middle support leg, shortening the length of the longitudinal guide beam, lengthening the lateral tracks of the front and middle supports, and reinforcing the lateral connection of the guide beam to ensure rotational stability; Step 2: Before formal erection, divide the bridge into 5 spans between platform 0 and platform 5. Mark the cap beams and bridge decks of spans 4 and 5 on the D ramp roadbed using lime to scale the bridge's plan dimensions. Then install the bridge erection machine. After the machine is installed, simulate the feeding and erection process of the fourth span, and summarize the results. The feeding route, erection process, and parameters were determined, and the simulated optimal route was marked on the actual roadbed and bridge deck with lime. Step 3: The bridge erecting machine was assembled at platform 5 of the D ramp bridge, with a length of 50m. A beam was used as a counterweight to cross the span to the 5th span. After crossing the span, the front and middle support legs were fixed, and the two overhead cranes were moved forward to the erection span. The last 10m truss section of the bridge erecting machine was dismantled sequentially using a crane. Before erection, the position of the bridge erecting machine was checked, and the beam was fed according to the route marked on the roadbed. When feeding the beam, the front overhead crane lifted one end of the beam and placed the other end on the beam transport vehicle. The bridge erecting machine and the beam transport vehicle cooperated to feed the beam. The rear overhead crane lifted the other end of the beam, and the two overhead cranes moved synchronously to feed the beam. After the two overhead cranes moved forward to their positions, they moved laterally at the same time. The precise position of the beam installation is determined, and limiting devices are set on the track. During lateral movement, the outrigger pulleys must not extend beyond the track within the beam's range. Prepare to lower the beam, ensuring it is approximately 10cm above the support. Lower one end first, then the other. Before lowering, tighten the wire rope at one end of the beam to ensure accurate placement. Step 4: After erecting the 5th span of the box girder, promptly weld the transverse diaphragms and wet joint reinforcement to enhance overall integrity and stability. The bridge erecting machine then crosses the span, and after this, pour the wet joint of the 5th span. Step 5: After the bridge erecting machine has crossed the span, ensure the front, middle, and rear outriggers are securely and effectively supported before starting the erection of the 4th span of the box girder. Before erection, mark the optimal simulated beam transport roadbed on the 5th span bridge surface with lime. According to the route, feed and erect the beams. After the beams are completed, weld the cross diaphragm reinforcement in time. Step 6: Transfer the bridge erecting machine to platform 0 and assemble it. When the bridge erecting machine crosses the span, the middle support leg is set behind the back wall of platform 0 from the back position of platform. Then erect the box girder of the first and second spans. Step 7: Support the rear support and rear support leg. Move the middle support leg to the large pile number of the beam end of the second span and adjust the angle. Then adjust the height of the front support leg. After all the preparatory procedures are completed, cross the span. After crossing the span, place the front support leg 1m away from the center line of the cap beam on the beam surface of the fourth span to avoid the beam not being able to be placed in place when erecting the outer beam. Pour the wet joint of the second span. After the strength meets the requirements, erect the third span. Before erection, mark the beam feeding route on the bridge surface with lime.It is evident that the bridge erection method for small-radius curved bridges has the problem that the large curvature of the small-radius curved bridges requires the bridge erection machine to move and erect the beams under complex geometric conditions, and the beams and bridge erection machine are prone to misalignment, which increases the difficulty of the erection. Summary of the Invention

[0004] To address this issue, the present invention provides an optimization method for adjusting the construction posture of bridges with small radius curves, steep slopes, and narrow spans. This method overcomes the problem in the prior art where the curvature of small radius curve bridges is relatively large, requiring the bridge erecting machine to move and the bridge beams to be erected under complex geometric conditions. This also makes it easy for the bridge beams and the bridge erecting machine to deviate, thus increasing the difficulty of the erection process.

[0005] To achieve the above objectives, this invention provides a method for adjusting and optimizing the construction posture of a narrow-span bridge with a small radius curve and steep slope, comprising: Obtain initial erection parameters and establish a construction posture control model based on the initial erection parameters, wherein the initial erection parameters include bridge geometric parameters, bridge erecting machine structural parameters, and environmental impact factors; The geometric design parameters of the target bridge section are input into the construction posture control model, and the initial erection path, outrigger adjustment method and predicted deviation parameters are output respectively. The bridge erecting machine is controlled to pass through the span and erect the beam according to the initial erection path and outrigger adjustment method, and the erection deviation parameters are collected. The erection deviation parameters include the main beam deflection angle of the bridge erecting machine, the outrigger settlement, and the lateral displacement of the outrigger wheel set. The attitude correction method is determined based on the deviation between the erection deviation parameter and the predicted deviation parameter. The attitude correction method includes adjusting the bridge erecting machine's steering coefficient, outrigger support force distribution, and lateral movement speed. When the deviation continues to exceed the preset threshold, a graded early warning method is implemented, including inserting an intermediate stable working condition processing method or recalculating the optimal attitude setup and adjustment path. Continue erecting the beam and adjusting the path according to the optimal posture to complete the beam positioning.

[0006] Furthermore, the process of establishing a construction posture control model based on the initial erection parameters includes: Three-dimensional models of the main bridge structure and the bridge erecting machine are established based on the bridge's geometric parameters and the bridge erecting machine's structural parameters, respectively. Using the aforementioned environmental impact factors as variables, the stress state of the bridge erecting machine during the process of crossing the span and erecting the beam was simulated by finite element analysis. Based on the analysis results of the stress state, a construction posture response database corresponding to environmental impact factors is established; The construction posture response database is trained to generate the construction posture control model.

[0007] Furthermore, the bridge geometric parameters include curve radius, longitudinal slope ratio, and bridge deck width; The structural parameters of the bridge erecting machine include the main beam length, leg spacing, and number of wheel sets. The environmental impact factors include wind load intensity, track smoothness, ambient temperature, and the coefficient of thermal expansion and contraction of bridge materials corresponding to the ambient temperature.

[0008] Furthermore, the deviation includes the main beam angle deviation of the bridge erecting machine, the maximum settlement of the outriggers, and the proportion of the wheel set lateral slippage exceeding the safety limit.

[0009] Furthermore, the main beam angle deviation is the absolute value of the difference between the actual deflection angle of the main beam of the bridge erecting machine and the theoretical trajectory angle in the initial erection path; the maximum settlement is the maximum value of the settlement corresponding to several legs; the proportion of the wheel set lateral slip exceeding the safety limit is the ratio of the absolute value of the difference between the wheel set lateral slip and the safety limit to the safety limit.

[0010] Furthermore, the process of implementing a tiered early warning system includes: If any parameter in the deviation is sampled for a certain number of consecutive times and the result is greater than or equal to the corresponding preset threshold, it is determined to be a first-level deviation and is inserted into the intermediate stable working condition processing mode. If two or more parameters in the deviation have a sampling result greater than or equal to the corresponding preset threshold for a certain number of consecutive times, it is determined to be a level two deviation, and the bridge erecting machine operation is suspended to recalculate the optimal posture erection adjustment path.

[0011] Furthermore, the intermediate stable working condition processing method is to control the bridge erecting machine to retreat along the initial erection path to the working condition before the first-level deviation was determined, and reduce the lateral speed to advance again.

[0012] Furthermore, the process of recalculating the optimal attitude setup and adjustment path is as follows: The sampling results of the deviation amount of a number of times that is determined to be a second-level deviation are used as feedback input to the construction posture control model; The erection path and corresponding outrigger adjustment method are recalculated based on the actual spatial orientation of the current bridge erecting machine.

[0013] Furthermore, the outrigger adjustment methods include adjusting the lateral position of the outrigger, adjusting the vertical height of the outrigger, and adjusting the load distribution of the outrigger.

[0014] Furthermore, the process of determining the attitude correction method based on the deviation between the set-up bias parameter and the predicted bias parameter includes: If the main beam angle deviation is greater than or equal to the corresponding preset threshold, then the steering angle difference between the front and rear outrigger wheel sets is reduced. If the maximum settlement is greater than or equal to the corresponding preset threshold, the load on the outrigger with the greatest pressure is reduced and the outrigger with the least pressure is controlled to lift. If the lateral slip of the wheel set exceeds the safety limit by a proportion greater than or equal to the corresponding preset threshold, the lateral speed is reduced.

[0015] Compared with existing technologies, the beneficial effects of this invention are as follows: the method described in this invention obtains initial erection parameters such as bridge geometric parameters, bridge erecting machine structural parameters, and environmental impact factors, and establishes a construction posture control model based on these multi-dimensional parameters. This achieves systematic modeling of the complex stress state and motion trajectory during the erection of narrow-span bridges with small-radius curves and steep slopes. Because traditional bridge erecting machines, when operating on small-radius curves, experience torsional stress accumulation in the main beam due to the mismatch between the main beam rigidity and the curved track, leading to lateral slippage of the outrigger wheel assembly or outrigger instability, this invention constructs a construction posture response database based on three-dimensional modeling and finite element analysis. Combined with machine learning training, it generates a control model that can dynamically predict erection behavior. This model can predict the deflection trend of the bridge erecting machine and the force distribution on the outriggers under different working conditions, thereby outputting the initial erection path, outrigger adjustment method, and predicted deflection parameters, significantly improving the controllability and safety of the erection process.

[0016] Furthermore, the method of this invention inputs the geometric design parameters of the target bridge segment into the construction posture control model, outputs the initial erection path and outrigger adjustment method, and collects erection deviation parameters such as the main beam deflection angle, outrigger settlement, and wheel set lateral displacement in real time during the actual erection process. Since minor unevenness of the track or fluctuations in wind load at the construction site can easily cause instantaneous disturbances in the posture of the bridge erecting machine, resulting in beam positioning deviations or even collision risks, this invention dynamically identifies key instability factors and generates corresponding posture correction methods by comparing the deviation between the measured deviation parameters and the model prediction values. These methods include adjusting the steering coefficient, optimizing the outrigger support force distribution, and adjusting the lateral movement speed, effectively suppressing posture inaccuracies caused by external disturbances or nonlinear structural responses, and improving erection accuracy and operational stability.

[0017] Furthermore, the method described in this invention establishes a graded early warning mechanism. When the deviation continuously exceeds a preset threshold, a differentiated response strategy is activated. When a single parameter continuously exceeds the standard, triggering a first-level deviation, an intermediate stable working condition processing mode is automatically inserted. That is, the bridge erecting machine is controlled to retreat to the previous stable position and the lateral speed is reduced to advance again, avoiding the accumulation of local errors and the evolution into overall loss of control. When two or more parameters simultaneously exceed the standard and are judged as a second-level deviation, the operation is immediately suspended, and historical deviation data is used as feedback information to input into the construction posture control model. The optimal posture erection adjustment path is recalculated in combination with the current actual spatial posture of the bridge erecting machine, realizing online adaptive updating of the model and path replanning. The coupling and accumulation of error propagation in the erection of small-radius curved bridges are considered, which can quickly restore system stability in the event of sudden disturbances or model prediction failure, ensuring construction safety under high-risk conditions.

[0018] Furthermore, the method described in this invention introduces environmental influencing factors such as the coefficient of thermal expansion and contraction corresponding to ambient temperature, wind load intensity, and track smoothness as variables to participate in finite element simulation and model training, enabling the construction posture control model to perceive and respond to changes in the external dynamic environment. Especially in construction environments with large diurnal temperature differences or desert aridity, the bridge structure undergoes slight deformation due to material expansion and contraction, which may change the original curve geometry and affect the trajectory of the bridge erecting machine. This invention improves the model's fitting degree and generalization ability to real construction scenarios by incorporating such environmental variables into the entire modeling process, and reduces erection deviations caused by time-varying environmental factors.

[0019] Furthermore, the method described in this invention dynamically distributes and adjusts the support force of the outriggers. When the maximum settlement exceeds the threshold, it actively reduces the load on the outriggers with concentrated pressure and lifts the outriggers with less stress, thereby achieving balanced control of the load on the outrigger system and preventing foundation settlement or structural buckling caused by overload of individual outriggers. At the same time, when the lateral slip of the wheel set exceeds the limit, the lateral speed is reduced. Combined with reducing the difference in steering angle between the front and rear outrigger wheel sets, this alleviates the problem of rail jamming or lateral thrust surge caused by excessive steering difference, and enhances the tracking performance and walking stability of the bridge erecting machine on sharp curves. Attached Figure Description

[0020] Figure 1 This is an overall flowchart of the method for adjusting and optimizing the construction posture of a narrow-span bridge with a small radius curve and steep slope, according to an embodiment of the present invention. Figure 2 This is a flowchart illustrating the construction posture control model for establishing an optimization method for the erection posture of a narrow-span bridge with a small radius curve and steep slope, as described in an embodiment of the present invention. Figure 3 This is a flowchart illustrating the graded early warning method for the construction posture adjustment and optimization method of a narrow-span bridge with a small radius curve and steep slope according to an embodiment of the present invention. Figure 4 This is a flowchart illustrating the determination of the attitude correction method for the construction attitude adjustment and optimization method of a narrow-span bridge with a small radius curve and steep slope, according to an embodiment of the present invention. Detailed Implementation

[0021] To make the objectives and advantages of the present invention clearer, the present invention will be further described below with reference to embodiments; it should be understood that the specific embodiments described herein are merely for explaining the present invention and are not intended to limit the present invention.

[0022] Preferred embodiments of the present invention will now be described with reference to the accompanying drawings. Those skilled in the art should understand that these embodiments are merely illustrative of the technical principles of the present invention and are not intended to limit the scope of protection of the present invention.

[0023] It should be noted that in the description of this invention, the terms "upper", "lower", "left", "right", "inner", "outer", etc., which indicate directions or positional relationships, are based on the directions or positional relationships shown in the accompanying drawings. This is only for the convenience of description and is not intended to indicate or imply that the device or element must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, it should not be construed as a limitation of this invention.

[0024] Furthermore, it should be noted that, in the description of this invention, unless otherwise explicitly specified and limited, the terms "installation," "connection," and "linking" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; and they can refer to the internal connection of two components. Those skilled in the art can understand the specific meaning of the above terms in this invention according to the specific circumstances.

[0025] Please see Figure 1 , Figure 2 , Figure 3 as well as Figure 4 The flowcharts shown are, respectively, the overall flowchart of the method for adjusting and optimizing the construction posture of a narrow-span bridge with a small radius curve and steep slope according to an embodiment of the present invention, the flowchart for establishing a construction posture control model for the adjustment and optimization method, the flowchart for implementing a graded early warning method, and the flowchart for determining the posture correction method. The present invention provides a method for adjusting and optimizing the construction posture of a narrow-span bridge with a small radius curve and steep slope, comprising: Obtain initial erection parameters and establish a construction posture control model based on the initial erection parameters, wherein the initial erection parameters include bridge geometric parameters, bridge erecting machine structural parameters, and environmental impact factors; The geometric design parameters of the target bridge section are input into the construction posture control model, and the initial erection path, outrigger adjustment method and predicted deviation parameters are output respectively. The bridge erecting machine is controlled to pass through the span and erect the beam according to the initial erection path and outrigger adjustment method, and the erection deviation parameters are collected. The erection deviation parameters include the main beam deflection angle of the bridge erecting machine, the outrigger settlement, and the lateral displacement of the outrigger wheel set. The attitude correction method is determined based on the deviation between the erection deviation parameter and the predicted deviation parameter. The attitude correction method includes adjusting the bridge erecting machine's steering coefficient, outrigger support force distribution, and lateral movement speed. When the deviation continues to exceed the preset threshold, a graded early warning method is implemented, including inserting an intermediate stable working condition processing method or recalculating the optimal attitude setup and adjustment path. Continue erecting the beam and adjusting the path according to the optimal posture to complete the beam positioning.

[0026] In practice, the method described in this invention acquires initial erection parameters such as bridge geometric parameters, bridge erecting machine structural parameters, and environmental impact factors. Based on these multidimensional parameters, a construction posture control model is established, realizing a systematic modeling of the complex stress state and motion trajectory during the erection of narrow-span bridges with small-radius curves and steep slopes. Because traditional bridge erecting machines, when operating on small-radius curves, experience torsional stress accumulation in the main beam due to the mismatch between the main beam rigidity and the curved track, leading to lateral slippage of the outrigger wheel assembly or outrigger instability, this invention constructs a construction posture response database based on three-dimensional modeling and finite element analysis. Combined with machine learning training, it generates a control model that can dynamically predict erection behavior. This model can predict the deflection trend of the bridge erecting machine under different working conditions and the stress distribution of the outriggers, thereby outputting the initial erection path, outrigger adjustment method, and predicted deflection parameters, significantly improving the controllability and safety of the erection process.

[0027] Specifically, the process of establishing a construction posture control model based on the initial erection parameters includes: Three-dimensional models of the main bridge structure and the bridge erecting machine are established based on the bridge's geometric parameters and the bridge erecting machine's structural parameters, respectively. Using the aforementioned environmental impact factors as variables, the stress state of the bridge erecting machine during the process of crossing the span and erecting the beam was simulated by finite element analysis. Based on the analysis results of the stress state, a construction posture response database corresponding to environmental impact factors is established; The construction posture response database is trained to generate the construction posture control model.

[0028] Specifically, finite element analysis is performed using ANSYS or ADAMS software.

[0029] In practice, the method of this invention inputs the geometric design parameters of the target bridge section into the construction posture control model, outputs the initial erection path and outrigger adjustment method, and collects erection deviation parameters such as the main beam deflection angle, outrigger settlement, and wheel set lateral displacement in real time during the actual erection process. Since minor unevenness of the track or fluctuations in wind load at the construction site can easily cause instantaneous disturbances in the posture of the bridge erecting machine, resulting in beam positioning deviations or even collision risks, this invention dynamically identifies key instability factors and generates corresponding posture correction methods by comparing the deviation between the measured deviation parameters and the model prediction values. These methods include adjusting the steering coefficient, optimizing the outrigger support force distribution, and adjusting the lateral movement speed, effectively suppressing posture inaccuracies caused by external disturbances or nonlinear structural responses, and improving erection accuracy and operational stability.

[0030] Specifically, the bridge geometric parameters include curve radius, longitudinal slope ratio, and bridge deck width; The structural parameters of the bridge erecting machine include the main beam length, leg spacing, and number of wheel sets. The environmental impact factors include wind load intensity, track smoothness, ambient temperature, and the coefficient of thermal expansion and contraction of bridge materials corresponding to the ambient temperature.

[0031] Specifically, the coefficient of thermal expansion is the rate of change of length of steel or concrete corresponding to a unit temperature change, where the unit temperature change is 1℃.

[0032] In practice, the method described in this invention introduces environmental factors such as the coefficient of thermal expansion and contraction corresponding to ambient temperature, wind load intensity, and track smoothness as variables to participate in finite element simulation and model training. This enables the construction posture control model to perceive and respond to changes in the external dynamic environment. Especially in construction environments with large diurnal temperature differences or desert aridity, the bridge structure undergoes slight deformation due to material expansion and contraction, which may change the original curve geometry and affect the trajectory of the bridge erecting machine. By incorporating such environmental variables into the entire modeling process, this invention improves the model's fitting degree and generalization ability to real construction scenarios and reduces erection deviations caused by time-varying environmental factors.

[0033] Specifically, the deviation includes the main beam angle deviation of the bridge erecting machine, the maximum settlement of the outriggers, and the proportion of the wheel set lateral slippage exceeding the safety limit.

[0034] Specifically, the main beam angle deviation is the absolute value of the difference between the actual deflection angle of the main beam of the bridge erecting machine and the theoretical trajectory angle in the initial erection path; the maximum settlement is the maximum value of the settlement corresponding to several legs; the proportion of the wheel set lateral slip exceeding the safety limit is the ratio of the absolute value of the difference between the wheel set lateral slip and the safety limit to the safety limit.

[0035] Specifically, the actual deflection angle and settlement of the main beam are detected by a laser rangefinder.

[0036] Specifically, the process of implementing a tiered early warning system includes: If any parameter in the deviation is sampled for a certain number of consecutive times and the result is greater than or equal to the corresponding preset threshold, it is determined to be a first-level deviation and is inserted into the intermediate stable working condition processing mode. If two or more parameters in the deviation have a sampling result greater than or equal to the corresponding preset threshold for a certain number of consecutive times, it is determined to be a level two deviation, and the bridge erecting machine operation is suspended to recalculate the optimal posture erection adjustment path.

[0037] Specifically, the deviation is sampled every 5 seconds; A series of times, not less than 3 times.

[0038] Specifically, the preset threshold value range for the main beam angle deviation is [1°, 5°]; the preset threshold value range for the maximum settlement of the outrigger is [2mm, 5mm]; and the preset threshold value range for the proportion of wheel set lateral slip exceeding the safety limit is [0.01, 0.1].

[0039] In implementation, the preferred embodiment of the preset threshold corresponding to the main beam angle deviation is 1.5°; the preferred embodiment of the preset threshold corresponding to the maximum settlement of the outrigger is 3mm; and the preferred embodiment of the preset threshold corresponding to the proportion of the wheel set lateral slip exceeding the safety limit is 0.05.

[0040] Specifically, the intermediate stable working condition processing method is to control the bridge erecting machine to retreat along the initial erection path to the working condition before the first-level deviation was determined, and reduce the lateral speed to advance again.

[0041] In implementation, the method of this invention establishes a graded early warning mechanism. When the deviation continuously exceeds a preset threshold, a differentiated response strategy is activated. When a single parameter continuously exceeds the standard and triggers a first-level deviation, an intermediate stable working condition processing mode is automatically inserted. That is, the bridge erecting machine is controlled to retreat to the previous stable position and the lateral speed is reduced to advance again, avoiding the accumulation of local errors and the evolution into overall loss of control. When two or more parameters simultaneously exceed the standard and are judged as a second-level deviation, the operation is immediately suspended, and historical deviation data is used as feedback information to input into the construction posture control model. The optimal posture erection adjustment path is recalculated in combination with the current actual spatial posture of the bridge erecting machine, realizing online adaptive updating of the model and path replanning. The coupling and accumulation of error propagation in the erection of small-radius curved bridges are considered, which can quickly restore system stability in the event of sudden disturbances or model prediction failure, ensuring construction safety under high-risk conditions.

[0042] Specifically, the process of recalculating the optimal attitude setup and adjustment path is as follows: The sampling results of the deviation amount of a number of times that is determined to be a second-level deviation are used as feedback input to the construction posture control model; The erection path and corresponding outrigger adjustment method are recalculated based on the actual spatial orientation of the current bridge erecting machine.

[0043] Specifically, the outrigger adjustment methods include adjusting the lateral position of the outrigger, adjusting the vertical height of the outrigger, and adjusting the load distribution of the outrigger.

[0044] Specifically, the actual spatial pose includes the current position of the bridge erecting machine, attitude angle, outrigger height, and lateral displacement of the wheel set; The actual spatial pose is determined by setting up a total station at control points with known coordinates along the bridge and installing prisms at the front and rear ends of the main beam of the bridge erecting machine. The total station automatically tracks the prisms to measure the three-dimensional coordinates of the bridge erecting machine in real time.

[0045] Specifically, the process of determining the attitude correction method based on the deviation between the set-up bias parameter and the predicted bias parameter includes: If the main beam angle deviation is greater than or equal to the corresponding preset threshold, then the steering angle difference between the front and rear outrigger wheel sets is reduced. If the maximum settlement is greater than or equal to the corresponding preset threshold, the load on the outrigger with the greatest pressure is reduced and the outrigger with the least pressure is controlled to lift. If the lateral slip of the wheel set exceeds the safety limit by a proportion greater than or equal to the corresponding preset threshold, the lateral speed is reduced.

[0046] Specifically, the difference in steering angle between the front and rear outrigger wheel sets is the difference between the average steering angle of the front outrigger wheel set and the average steering angle of the rear outrigger wheel set.

[0047] Specifically, the difference in steering angle between the front and rear outrigger wheel sets is adjusted by the rotation motor of the outrigger wheel sets; The load on the outriggers is adjusted via hydraulic cylinders; The lateral movement speed is adjusted by the lateral movement motor of the bridge erecting machine.

[0048] In practice, if the difference between the main beam angle deviation and the corresponding preset threshold exceeds 1°, the steering angle difference between the front and rear outrigger wheel sets will decrease by 1°. If the difference between the maximum deposition amount and the corresponding preset threshold exceeds 1 mm, the load of the support leg with the highest pressure is reduced to 0.95 of the original value. While reducing the load of the support leg with the highest pressure, the support leg with the lowest pressure is increased to maintain the levelness. If the difference between the proportion of the wheel set's lateral slip exceeding the safety limit and the corresponding preset threshold exceeds 0.01, the lateral speed will be reduced to 0.95 of the original value. In practice, the method described in this invention dynamically distributes and adjusts the support force of the outriggers. When the maximum settlement exceeds the threshold, it actively reduces the load on the outriggers with concentrated pressure and lifts the outriggers with less stress, thereby achieving balanced control of the load on the outrigger system and preventing foundation settlement or structural buckling caused by overload of individual outriggers. At the same time, when the lateral slip of the wheel set exceeds the limit, the lateral speed is reduced. Combined with reducing the difference in steering angle between the front and rear outrigger wheel sets, the problem of rail jamming or lateral thrust surge caused by excessive steering difference is alleviated, thereby enhancing the tracking performance and walking stability of the bridge erecting machine on sharp curves.

[0049] The technical solution of the present invention has been described above with reference to the preferred embodiments shown in the accompanying drawings. However, it will be readily understood by those skilled in the art that the scope of protection of the present invention is obviously not limited to these specific embodiments. Without departing from the principles of the present invention, those skilled in the art can make equivalent changes or substitutions to the relevant technical features, and the technical solutions after these changes or substitutions will all fall within the scope of protection of the present invention.

Claims

1. A method for adjusting and optimizing the construction posture of a narrow-span bridge with a small radius curve and steep slope, characterized in that, include: Obtain initial erection parameters and establish a construction posture control model based on the initial erection parameters, wherein the initial erection parameters include bridge geometric parameters, bridge erecting machine structural parameters, and environmental impact factors; The geometric design parameters of the target bridge section are input into the construction posture control model, and the initial erection path, outrigger adjustment method and predicted deviation parameters are output respectively. The bridge erecting machine is controlled to pass through the span and erect the beam according to the initial erection path and outrigger adjustment method, and the erection deviation parameters are collected. The erection deviation parameters include the main beam deflection angle of the bridge erecting machine, the outrigger settlement, and the lateral displacement of the outrigger wheel set. The attitude correction method is determined based on the deviation between the erection deviation parameter and the predicted deviation parameter. The attitude correction method includes adjusting the bridge erecting machine's steering coefficient, outrigger support force distribution, and lateral movement speed. When the deviation continues to exceed the preset threshold, a graded early warning method is implemented, including inserting an intermediate stable working condition processing method or recalculating the optimal attitude setup and adjustment path. Continue erecting the beam and adjusting the path according to the optimal posture to complete the beam positioning.

2. The method for adjusting and optimizing the construction posture of a narrow-span bridge with a small radius curve and steep slope according to claim 1, characterized in that, The process of establishing a construction posture control model based on the initial erection parameters includes: Three-dimensional models of the main bridge structure and the bridge erecting machine are established based on the bridge's geometric parameters and the bridge erecting machine's structural parameters, respectively. Using the aforementioned environmental impact factors as variables, the stress state of the bridge erecting machine during the process of crossing the span and erecting the beam was simulated by finite element analysis. Based on the analysis results of the stress state, a construction posture response database corresponding to environmental impact factors is established; The construction posture response database is trained to generate the construction posture control model.

3. The method for adjusting and optimizing the construction posture of a narrow-span bridge with a small radius curve and steep slope according to claim 2, characterized in that, The bridge's geometric parameters include curve radius, longitudinal slope ratio, and bridge deck width. The structural parameters of the bridge erecting machine include the main beam length, leg spacing, and number of wheel sets. The environmental impact factors include wind load intensity, track smoothness, ambient temperature, and the coefficient of thermal expansion and contraction of bridge materials corresponding to the ambient temperature.

4. The method for adjusting and optimizing the construction posture of a narrow-span bridge with a small radius curve and steep slope according to claim 3, characterized in that, The deviations include the main beam angle deviation of the bridge erecting machine, the maximum settlement of the outriggers, and the proportion of wheel set lateral slippage exceeding the safety limit.

5. The method for adjusting and optimizing the construction posture of a narrow-span bridge with a small radius curve and steep slope according to claim 4, characterized in that, The main beam angle deviation is the absolute value of the difference between the actual deflection angle of the main beam of the bridge erecting machine and the theoretical trajectory angle in the initial erection path; the maximum settlement is the maximum value of the settlement corresponding to several legs; the proportion of the wheel set lateral slip exceeding the safety limit is the ratio of the absolute value of the difference between the wheel set lateral slip and the safety limit to the safety limit.

6. The method for adjusting and optimizing the construction posture of a narrow-span bridge with a small radius curve and steep slope according to claim 5, characterized in that, The process of implementing a tiered early warning system includes: If any parameter in the deviation is sampled for a certain number of consecutive times and the result is greater than or equal to the corresponding preset threshold, it is determined to be a first-level deviation and is inserted into the intermediate stable working condition processing mode. If two or more parameters in the deviation have a sampling result greater than or equal to the corresponding preset threshold for a certain number of consecutive times, it is determined to be a level two deviation, and the bridge erecting machine operation is suspended to recalculate the optimal posture erection adjustment path.

7. The method for adjusting and optimizing the construction posture of a narrow-span bridge with a small radius curve and steep slope according to claim 6, characterized in that, The intermediate stable working condition processing method is to control the bridge erecting machine to retreat along the initial erection path to the working condition before the first-level deviation was determined, and reduce the lateral speed to advance again.

8. The method for adjusting and optimizing the construction posture of a narrow-span bridge with a small radius curve and steep slope according to claim 7, characterized in that, The process of recalculating the optimal attitude setup and adjustment path is as follows: The sampling results of the deviation amount of a number of times that is determined to be a second-level deviation are used as feedback input to the construction posture control model; The erection path and corresponding outrigger adjustment method are recalculated based on the actual spatial orientation of the current bridge erecting machine.

9. The method for adjusting and optimizing the construction posture of a narrow-span bridge with a small radius curve and steep slope according to claim 8, characterized in that, The outrigger adjustment methods include adjusting the lateral position of the outrigger, adjusting the vertical height of the outrigger, and adjusting the load distribution of the outrigger.

10. The method for adjusting and optimizing the construction posture of a narrow-span bridge with a small radius curve and steep slope according to claim 9, characterized in that, The process of determining the attitude correction method based on the deviation between the established bias parameter and the predicted bias parameter includes: If the main beam angle deviation is greater than or equal to the corresponding preset threshold, then the steering angle difference between the front and rear outrigger wheel sets is reduced. If the maximum settlement is greater than or equal to the corresponding preset threshold, the load on the outrigger with the highest pressure is reduced and the outrigger with the lowest pressure is controlled to lift. If the lateral slip of the wheel set exceeds the safety limit by a proportion greater than or equal to the corresponding preset threshold, the lateral speed is reduced.

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