Cast-in-place box girder formwork sliding device and construction method thereof

Abstract

The invention belongs to the technical field of bridge construction, and particularly relates to a cast-in-place box girder formwork sliding device and a construction method thereof.The device comprises a sliding rail system, a formwork fixing platform and a traction system, the sliding rail system is formed by detachably splicing multiple sections of I-shaped steel, and the formwork fixing platform is of an integrated frame structure; a roller group matched with the sliding track system is arranged at the bottom of the template fixing platform, and an adjustable template rolling shaft is arranged at the top of the template fixing platform; the traction system is used for driving the template fixing platform to slide along the sliding rail system; the construction method comprises the steps of parameter matching, track laying and positioning, formwork mounting and fastening, sliding propulsion control, position correction locking and cyclic displacement operation, deviation is corrected through closed-loop regulation and control in sliding, and positioning adopts a three-level alignment and multiple locking positioning mechanism to guarantee precision; the problems existing in traditional cast-in-place box girder formwork construction are solved, and the construction goals of mechanization, high precision, high adaptability, safety and stability are achieved.

Description

Technical Field

[0001] This invention relates to the field of bridge construction technology, specifically to a formwork sliding device for cast-in-place box girders and its construction method. Background Technology

[0002] In the construction of cast-in-place box girders for high-speed railways, the relocation and positioning of formwork is one of the key processes. In cast-in-place box girder construction, the relocation and precise positioning of formwork directly determine the construction quality, efficiency, and cost control. Traditional construction methods mainly rely on hoisting equipment or manual handling for formwork relocation, which has several technical drawbacks: High labor intensity and low construction efficiency: manual handling is cumbersome, time-consuming and labor-intensive, and hoisting operations require the coordination of multiple equipment, which makes it difficult to meet the needs of large-scale continuous construction. Severe wear and tear on formwork: Formwork is prone to collision and deformation during hoisting. Improper handling by manual labor further aggravates formwork wear, resulting in high frequency of formwork replacement and increased costs. Insufficient positioning accuracy: Relying on manual experience to adjust the template position, lacking effective dynamic control methods, the sliding process is prone to cumulative offset, making it difficult to meet the stringent requirements of high-speed rail construction, such as positioning deviation ≤3mm; Poor scenario adaptability: The construction schemes are mostly fixed and are not dynamically adjusted according to scenario parameters such as beam span length, formwork weight, site flatness, and ambient wind speed. As a result, the construction stability is poor in complex scenarios such as large spans, high piers, and strong winds. Low equipment reuse rate: Traditional equipment is mostly customized and cannot be adapted to the construction of cast-in-place box girders of different spans and types, resulting in high equipment investment costs; Insufficient construction safety: The lack of real-time safety monitoring and early warning mechanisms makes it difficult to predict safety hazards in high-pier construction, long-distance sliding and other risky scenarios, which can easily lead to safety accidents such as equipment instability and formwork falling.

[0003] Therefore, there is an urgent need to design a template sliding device and construction method that can solve the above-mentioned technical problems. Summary of the Invention

[0004] To address the problems of existing technologies, this invention provides a formwork sliding device for cast-in-place box girders, comprising: A sliding track system, which is composed of multiple detachable and spliced ​​sections of I-beams, is used to provide guiding support for the sliding of the template; A template fixing platform is located at the top of the sliding track system. The template fixing platform is an integrated frame structure. The bottom of the template fixing platform is equipped with a roller group that matches the sliding track system. The top of the template fixing platform is equipped with an adjustable template roller for bearing and driving the template to slide synchronously. A traction system, connected to the template fixing platform, includes a winch, a wire rope, and a remote controller, used to pull the template fixing platform along the sliding track system.

[0005] Furthermore, it includes a detection unit and a controller; The detection unit is used to acquire construction scene parameters; The controller is electrically connected to the detection unit and has a built-in preset construction scenario and sliding parameter mapping model, which is used to automatically match the sliding parameters based on the construction scenario parameters.

[0006] Furthermore, it also includes a template fulcrum lifting mechanism and a braking device, located at the top and bottom of the template fixing platform, respectively. The braking device is used to lock the template fixing platform on the sliding track system, and the template fulcrum lifting mechanism is used to lift the template to adjust its vertical height.

[0007] Furthermore, it also includes a slip condition monitoring unit and a closed-loop adjustment module; The slip state monitoring unit is used to monitor at least one parameter among slip speed, track deformation, template offset and template fixing platform tilt angle, and is connected to the remote controller of the traction system through the closed-loop adjustment module to form closed-loop control. The closed-loop adjustment module is installed inside the side channel steel frame of the template fixing platform. The input end of the closed-loop adjustment module is connected to the sliding state monitoring unit, the detection unit and the remote controller. The output end of the closed-loop adjustment module is connected to the adjustable template roller and the braking device. The output end of the closed-loop adjustment module is also connected to an audible and visual alarm device, thus forming a closed-loop control system.

[0008] A method for slip-fitting formwork construction of cast-in-place box girder based on the aforementioned device includes the following steps: S1. Obtain construction scene parameters through the detection unit, and automatically match the construction parameters of the track based on the preset construction scene and sliding parameter mapping model; S2. Lay the sliding track system on the top surface of the cast-in-place support according to the construction plan path; fix the traction system at the preset position on the top of the pier at the end of the next span of the cast-in-place beam, so that the traction system and the sliding track system are coaxial. S3. Lower the template to the top of the template fixing platform, operate the template support lifting mechanism to lower the template to the preset bearing surface, drive the template to move laterally through the adjustable template rollers at the top of the template fixing platform, so that the template is completely separated from the concrete surface of the beam; fasten the template to the template fixing platform to form a rigid whole that slides synchronously. S4. The traction system outputs traction force at a preset speed to pull the template fixing platform carrying the template to slide along the track. During the sliding process, the cooperation status between the track and the template fixing platform is monitored in real time. S5. When the template slides to the target construction position, a three-level alignment and multiple locking positioning mechanism is adopted to achieve precise fixing of the template and the bottom formwork; S6. After the concrete is poured and the strength reaches the preset value, loosen the connection between the formwork and the bottom formwork, and use the formwork support lifting mechanism to lower the formwork back to the top surface of the formwork fixing platform. Repeat steps S3 to S5 to realize the cyclic sliding use of the formwork.

[0009] Furthermore, during the sliding process in step S4, the sliding state parameters are monitored in real time by the sliding state monitoring unit. Sliding stable state parameters are constructed based on the mechanical balance mechanism, and a stable threshold range is preset. When the state parameters exceed the threshold, the control mechanism is automatically activated. The winch traction force distribution is finely adjusted by the remote controller, and the adjustable template rollers on the top of the template fixing platform are driven to compensate for the horizontal offset of the template.

[0010] Furthermore, a three-level alignment and multi-locking positioning mechanism is adopted. The three-level alignment is as follows: Level 1 alignment uses laser positioning equipment to detect the overall extension direction of the track and the straightness of the joints of each I-beam segment; if track path deviation or misalignment is detected, the deviation between the track extension direction and the planned construction path is kept within a preset value by adjusting the bottom support of the track and tightening the fasteners between the track and the cast-in-place support, and the track joints are flat and without misalignment; Level 2 alignment uses a real-time sliding state monitoring unit to collect horizontal offset data during the sliding process of the template, and dynamically corrects the sliding amount based on the horizontal offset data; Level 3 alignment uses the lifting adjustment of the template support lifting mechanism to match the vertical elevation of the template with the preset elevation of the bottom formwork. The multiple locking mechanisms are as follows: primary locking uses a braking device to lock the relative position of the template fixing platform and the track; secondary locking uses fasteners to connect the template and the bottom mold, with the fastening torque of the fasteners automatically determined by an automatic ratchet wrench; and tertiary locking uses side auxiliary support components to fix the sides of the template and the cast-in-place support.

[0011] Furthermore, it also includes an automated security unit, specifically comprising: Before construction, based on the construction scenario parameters obtained by the detection unit, the safety risk points of high pier construction and long-distance sliding scenarios are predicted, and the structural strength of the device parts corresponding to the safety risk points is strengthened. During the sliding advance process in step S4, safety parameters are monitored in real time. These parameters include winch load, bolt tightness, connection stability between the track and the cast-in-place support, and ambient wind speed. Normal thresholds for each safety parameter are preset. When any safety parameter is detected to exceed the normal threshold, the closed-loop adjustment module automatically triggers an alarm and suspends the sliding construction. The sliding advance process in step S4 is resumed after the hidden danger is eliminated.

[0012] The beneficial effects of this invention are: This invention solves the technical problems of high labor intensity, low construction efficiency, severe formwork damage, insufficient positioning accuracy, poor scene adaptability, low reuse rate, and prominent safety hazards in traditional cast-in-place box girder formwork construction by collaboratively designing components such as a sliding track system, a formwork fixing platform, a traction system, a detection unit, a sliding state monitoring unit, and a closed-loop adjustment module, as well as setting up a construction scene and sliding parameter mapping model, a three-level alignment and multi-locking positioning mechanism, and an active safety assurance unit. It achieves the construction goals of mechanization, high precision, high adaptability, and safe and stable construction. Attached Figure Description

[0013] Figure 1 This is a front view of the formwork fixing platform in the cast-in-place box girder formwork sliding device of the present invention; Figure 2 This is a top view of the formwork fixing platform in the cast-in-place box girder formwork sliding device of the present invention; Figure 3 This is a flowchart of the formwork sliding construction method for cast-in-place box girders according to the present invention; Figure label: In the diagram: 1- Template fixing platform; 2- Adjustable template roller; 3- Roller assembly. Detailed Implementation

[0014] 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 some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0015] Please see Figure 1-3 The present invention provides a formwork sliding device for cast-in-place box girders, comprising: A sliding track system, which is composed of multiple detachable and spliced ​​sections of I-beams, is used to provide guiding support for the sliding of the template; The template fixing platform 1 is located at the top of the sliding track system. The template fixing platform 1 is an integrated frame structure. The bottom of the template fixing platform 1 is provided with a roller group 3 that matches the sliding track system. The top of the template fixing platform 1 is provided with an adjustable template roller 2, which is used to support and drive the template to slide synchronously. A traction system, connected to the template fixing platform 1, includes a winch, a wire rope, and a remote controller, used to drive the template fixing platform 1 to slide along the sliding track system; Furthermore, it also includes a detection unit and a controller; The detection unit is used to acquire construction scene parameters; The controller is electrically connected to the detection unit and has a built-in preset construction scenario and sliding parameter mapping model, which is used to automatically match the sliding parameters based on the construction scenario parameters.

[0016] Furthermore, it also includes a template fulcrum lifting mechanism and a braking device, located at the top and bottom of the template fixing platform 1, respectively. The braking device is used to lock the template fixing platform 1 on the sliding track system, and the template fulcrum lifting mechanism is used to lift the template to adjust the vertical height of the template.

[0017] Furthermore, it also includes a slip condition monitoring unit and a closed-loop adjustment module; The slip state monitoring unit is used to monitor at least one parameter among slip speed, track deformation, template offset and template fixing platform 1 tilt angle, and is connected to the remote controller of the traction system through the closed-loop adjustment module to form closed-loop control.

[0018] The closed-loop adjustment module is installed inside the side channel steel frame of the template fixing platform 1. The input end of the closed-loop adjustment module is connected to the sliding state monitoring unit, the detection unit and the remote controller. The output end of the closed-loop adjustment module is connected to the adjustable template roller 2 and the braking device. The output end of the closed-loop adjustment module is also connected to an audible and visual alarm device, thus forming a closed-loop control system.

[0019] It should be noted that the sliding track system is composed of multiple detachable H-beams, providing stable guiding support for the sliding of the formwork. The H-beams are preferably I20 H-beams, with joints rigidly connected by fasteners to ensure a smooth, non-misaligned joint. The formwork fixing platform 1 is an integrated frame structure, integrally formed from 14mm steel plates, 22-channel steel, and 10-channel steel. The 22-channel steel forms a rectangular frame, with the diagonals and adjacent 22-channel steel sections reinforced by 10-channel steel connections. The top of the rectangular frame is welded to the 14mm steel plate. The bottom of the formwork fixing platform 1 is equipped with roller sets 3 matching the sliding track system. The roller sets 3 roll in contact with the upper flange of the H-beams, converting sliding friction into rolling friction and reducing sliding resistance. An adjustable formwork roller 2 is located at the top, driving the formwork to move laterally and allowing for fine-tuning in the horizontal direction. The traction system includes a winch, wire rope, and remote controller; the winch is preferably a 5-ton type. The system can stably output traction force, and the remote controller enables remote control of the traction process, improving construction convenience. The detection unit is a modular sensing and data acquisition component, including a distance sensor, weight sensor, flatness sensor, wind speed sensor, data acquisition module, and power supply module. It is used to acquire construction scenario parameters such as beam span length, formwork weight, site flatness, and ambient wind speed, providing data support for dynamic adaptation of construction plans. The controller is electrically connected to the detection unit and has a built-in preset construction scenario and sliding parameter mapping model. Based on the construction scenario parameters acquired by the detection unit, it automatically matches key construction parameters such as track splicing density and initial traction speed. The sliding status monitoring unit is a sensing and monitoring component used to monitor the dynamic parameters of the formwork sliding process in real time, including a speed sensor, displacement sensor, strain sensor, tilt sensor, real-time data transmission module, and alarm triggering module. It is used to monitor parameters such as sliding speed, track deformation, formwork offset, and platform tilt angle in real time. Closed-loop adjustment module: Integrated and installed inside the side channel steel frame of the template fixing platform 1, it is encapsulated together with the data acquisition module of the detection unit and the data transmission module of the slip state monitoring unit in a waterproof and dustproof metal box; the metal box is rigidly fixed to the 22 channel steel of the template fixing platform 1 by bolts, and avoids the moving parts such as the roller group 3 and the adjustable template roller 2 of the template fixing platform 1; the metal box has a protection level of not less than IP65, built-in heat sink, and is suitable for the working temperature range of -10℃ to 60℃ at the construction site; the closed-loop adjustment module shares a 24V DC power supply module with the detection unit and the slip state monitoring unit, and is equipped with a backup lithium battery to achieve power supply redundancy guarantee; the closed-loop adjustment module establishes signal input connection with the slip state monitoring unit, the detection unit, and the remote controller, and establishes control output connection with the adjustable template roller 2, the braking device, and the audible and visual alarm device, and realizes the feedback of the control effect through a two-way link, thus forming a closed-loop control system; Template support lifting mechanism and braking device: The template support lifting mechanism is located at the top of the template fixing platform 1, preferably a hydraulic lifting rod with a lifting accuracy of ±0.5mm, used to lift the template to adjust the vertical height and achieve precise vertical elevation matching; The braking device is located at the bottom of the template fixing platform 1, preferably a caliper brake, used to lock the template fixing platform 1 on the sliding track system to prevent displacement during sliding or after positioning.

[0020] A method for slip-fitting formwork construction of cast-in-place box girder based on the aforementioned device includes the following steps: S1. Obtain construction scene parameters through the detection unit, and automatically match the construction parameters of the track based on the preset construction scene and sliding parameter mapping model; S2. Track laying and positioning: I-beam track units are laid flat on the top surface of the cast-in-place support according to the construction plan. The track is rigidly fixed to the support with fasteners to ensure that the track splicing is flat and without misalignment. The traction system is fixed at the preset position on the top of the pier at the end of the next span of the cast-in-place beam so that the traction system and the sliding track system are coaxial. S3. Template Installation and Fastening: Lower the template to the top surface of the template fixing platform 1, operate the template fulcrum lifting mechanism to lower the template to the preset bearing surface, drive the template to move laterally through the adjustable template roller 2 at the top of the template fixing platform 1, so that the template is completely separated from the concrete surface of the beam; fasten the template to the template fixing platform 1 to form a rigid whole that slides synchronously. S4. Sliding propulsion control: Release the braking device of the template fixing platform 1, start the winch through the remote controller, output traction force at the preset speed, drive the template fixing platform 1 to slide along the track carrying the template, and monitor the cooperation status between the track and the template fixing platform 1 in real time during the sliding process. S5. Position Correction and Locking: When the template slides to the target construction position, a three-level alignment and multiple locking positioning mechanism is adopted to complete the three-level alignment and multiple locking in sequence, so as to achieve precise fixation of the template and the bottom formwork. S6. Cyclic relocation operation: After the concrete is poured and the strength reaches the preset value, loosen the connection between the formwork and the bottom formwork, and use the formwork support lifting mechanism to lower the formwork back to the top surface of the formwork fixing platform 1. Repeat steps S3 to S5 to realize the cyclic sliding use of the formwork.

[0021] Furthermore, during the sliding process in step S4, the sliding state parameters are monitored in real time by the sliding state monitoring unit. Sliding stable state parameters are constructed based on the mechanical balance mechanism, and a stable threshold range is preset. When the state parameters exceed the threshold, the control mechanism is automatically activated. The winch traction force distribution is finely adjusted by the remote controller, and the adjustable template rollers on the top of the template fixing platform 1 are driven to compensate for the horizontal offset of the template.

[0022] It should be noted that the sliding stability parameters are constructed based on the mechanical equilibrium mechanism, and a preset stability threshold range is included. Specifically, the critical tangential stress is calculated based on the measured normal and tangential stresses of the current sliding surface. If the tangential stress is not less than the critical tangential stress, the system is unstable; if the tangential stress is less than the critical tangential stress, the system is stable. The stability parameters can be expressed as a safety factor. Stability is achieved when the safety factor is not less than 1. The control mechanism is centered on the sliding state monitoring unit, closed-loop adjustment module, and execution components, linking the detection unit, traction system, adjustable template rollers, and braking device components to form a complete control link. The closed-loop logic of real-time monitoring, data feedback, intelligent decision-making, and execution adjustment solves problems such as deviation and instability during the sliding process, ensuring construction accuracy and safety.

[0023] Furthermore, a three-level alignment and multi-locking positioning mechanism is adopted. The three-level alignment is as follows: Level 1 alignment uses laser positioning equipment to detect the overall extension direction of the track and the straightness of the joints of each I-beam segment; if track path deviation or misalignment is detected, the deviation between the track extension direction and the planned construction path is kept within a preset value by adjusting the bottom support of the track and tightening the fasteners between the track and the cast-in-place support, and the track joints are flat and without misalignment; Level 2 alignment uses a real-time sliding state monitoring unit to collect horizontal offset data during the sliding process of the template, and dynamically corrects the sliding amount based on the horizontal offset data; Level 3 alignment uses the lifting adjustment of the template support lifting mechanism to match the vertical elevation of the template with the preset elevation of the bottom formwork. The multiple locking mechanisms are as follows: primary locking uses a braking device to lock the relative position of the template fixing platform and the track; secondary locking uses fasteners to connect the template and the bottom mold, with the fastening torque of the fasteners automatically determined by an automatic ratchet wrench; and tertiary locking uses side auxiliary support components to fix the sides of the template and the cast-in-place support. It should be noted that step S5 employs a three-level alignment and multi-locking positioning mechanism. Its core purpose is to achieve high-precision three-dimensional alignment and long-term stable locking of the template and the bottom mold through layered alignment control and multi-dimensional locking protection. The specific implementation process is as follows: First-level alignment: Track path benchmark calibration. After the sliding track system is laid, laser positioning equipment is used to perform full-coverage accuracy testing on the overall extension direction of the track and the straightness of each I-beam splice. If the test reveals track path deviation or splicing misalignment, the track bottom support pads are adjusted and the fasteners between the track and the cast-in-place support are tightened to ensure that the deviation between the track extension direction and the planned construction path is ≤2mm, and that the track splices are flat and without misalignment, with a height difference of ≤0.5mm. This establishes a precise guiding benchmark for template sliding. The laser positioning equipment includes a laser line projector and a total station. Secondary alignment: Dynamic correction during the sliding process. During the sliding of the template along the sliding track system, the sliding status monitoring unit is activated. This unit includes displacement sensors and tilt sensors, which collect the horizontal offset and sliding direction deflection angle of the template in real time at a sampling frequency of ≥10Hz, with measurement accuracy controlled within ±0.1mm. When the monitoring data shows that the horizontal offset of the template is ≥1.5mm or the sliding direction deflection angle is ≥0.01°, the closed-loop adjustment module automatically triggers the control mechanism: the traction force distribution of the winch in the traction system is finely adjusted through the remote controller. If the template shifts to the right, the traction force output on the left is increased, and the adjustable template roller at the top of the template fixing platform is driven to move laterally to compensate for the horizontal offset of the template, ensuring that the template always slides along the designed sliding path, and ultimately ensuring that the horizontal offset of the template during the sliding process is ≤1mm.

[0024] Three-stage alignment: Precise vertical elevation matching. After the formwork slides to the target construction plane position, the formwork support lifting mechanism at the top of the formwork fixing platform is activated. Combined with real-time monitoring of the formwork top surface height by an elevation measuring instrument, the vertical position of the formwork is finely adjusted through the formwork support lifting mechanism. This ensures that the deviation between the vertical elevation of the formwork and the preset elevation of the bottom formwork is ≤0.8mm, and the overall flatness error of the formwork top surface is ≤1mm / m. This achieves precise vertical matching between the formwork and the bottom formwork, realizing precise three-dimensional alignment of the formwork and the bottom formwork. The formwork support lifting mechanism is a hydraulic lifting rod with a lifting accuracy of ±0.5mm, and the elevation measuring instrument is a level. Primary locking: After the template completes three-stage alignment, the braking device at the bottom of the template fixing platform is triggered, causing the braking element of the device to fit tightly against the upper flange of the I-beam in the sliding track system. The friction between the braking element and the I-beam limits the relative horizontal displacement between the template fixing platform and the track. A horizontal thrust of 5kN is applied to check the locking status. Once it is confirmed that the template fixing platform is not loose, the template is temporarily and securely locked. The braking device is a caliper brake with a response time ≤0.5s. Secondary locking: High-strength M24 bolts are used as fasteners, which penetrate the pre-set connection holes between the template and the bottom formwork. The fasteners are arranged at intervals of ≤30cm along the circumference of the template. An automatic ratchet wrench is used to tighten the fasteners, ensuring that the deviation between the actual tightening torque and the target tightening torque is ≤±5%, so that the template and the bottom formwork form a rigid connection structure to resist the vertical and horizontal forces generated during concrete pouring.

[0025] Three-level locking: Adjustable rigid support rods are installed on the side of the formwork as auxiliary supports. One end of the auxiliary support is rigidly connected to the channel steel frame on the side of the formwork, and the other end is rigidly fixed to the cast-in-place support. The bolts at the connection points between the auxiliary support and the formwork / cast-in-place support have a tightening torque ≥25 N·m, and the auxiliary supports are installed at intervals ≤1.5m, forming a lateral support and protection structure for the formwork to resist tilting or displacement caused by external forces such as strong wind loads and concrete lateral pressure. This multi-level locking system solves the technical pain points of insufficient accuracy and poor locking stability in traditional positioning methods, meeting the high-precision requirements of high-speed rail construction. The side auxiliary support is an adjustable rigid support structure used for the three-level alignment and multiple locking positioning mechanism of the cast-in-place box girder formwork sliding device. It realizes the lateral fixation of the formwork side and the cast-in-place support, and works in conjunction with the primary locking of the formwork fixing platform 1 of the braking device and the track, and the secondary locking of the formwork and the bottom formwork by high-strength bolts to form a multi-locking protection for the formwork and the bottom formwork. The side auxiliary support includes a fixed base, an adjustable support rod, a formwork connection end and a reinforcing component. The components are rigidly connected to form an integrated support structure, which is adapted to the lateral distance between the cast-in-place support and the formwork, resists lateral force disturbance during construction, and ensures the stability of the formwork after positioning.

[0026] The construction process adopts a standardized and modular operation design, and both the formwork fixing platform 1 and the sliding track system adopt a detachable splicing structure. The standardized and modular operation design includes: specifying the track splicing flatness tolerance of the sliding track system, the spacing of the fixing bolts between the formwork and the formwork fixing platform 1, and the threshold of the formwork sliding and advancing speed as standardized operation parameters. The detachable splicing structure allows the formwork fixing platform 1 and the sliding track system to be assembled and adapted according to different spans and structural types of cast-in-place box girders, realizing multi-scenario construction reuse.

[0027] Furthermore, it also includes an automated security unit, specifically comprising: Before construction, based on the construction scenario parameters obtained by the detection unit, the safety risk points of high pier construction and long-distance sliding scenarios are predicted, and the structural strength of the device parts corresponding to the safety risk points is strengthened. During the sliding advance process in step S4, safety parameters are monitored in real time. These parameters include winch load, bolt tightness, connection stability between the track and the cast-in-place support, and ambient wind speed. Normal thresholds for each safety parameter are preset. When any safety parameter is detected to exceed the normal threshold, the closed-loop adjustment module automatically triggers an alarm and suspends the sliding construction. The sliding advance process in step S4 is resumed after the hidden danger is eliminated.

[0028] It should be noted that the key to identifying and predicting safety risks in high-pier construction and long-distance sliding critical scenarios before construction is based on the input parameter system of the construction scenario and sliding parameter mapping model. Combining the risk characteristics of the two types of scenarios, the process is systematically carried out in four stages: scenario parameter collection, risk correlation analysis, risk level determination, and risk point location. The specific process and methods are as follows: I. Define the scope of core scenario parameter collection The risks associated with high-pier construction and long-distance slippage are strongly correlated with specific scenario parameters. Therefore, the following key parameters should be prioritized for data collection to provide a data foundation for risk identification:

[0029] II. Establishing Parameter-Risk Association Mapping Rules Based on historical engineering case data and mechanical simulation analysis, a quantitative correlation is established between the collected scene parameters and typical safety risk points in two types of scenarios, forming a directly callable "parameter threshold-risk point" correspondence rule, as follows: (I) High pier construction scenario: focusing on risks of "overturning resistance, wind load resistance, and support stability".

[0030] (II) Long-distance skidding scenario: focusing on the risks of "accumulated deviation, track failure, and loss of traction control".

[0031] III. Risk Level Determination and Priority Ranking By using a two-dimensional approach—"number of parameters exceeding standards" and "severity of risk consequences"—identified risk points are categorized into risk levels to clearly define the key risks that must be addressed before construction, thus avoiding resource waste. The specific judgment criteria are as follows:

[0032] IV. Concretization of Risk Points and Countermeasures After identifying risk points, it is necessary to combine the equipment structure and construction process to determine the specific location where the risk may occur, and to formulate targeted pre-control measures to ensure that the risk points can be effectively managed.

[0033] It is evident that identifying risk points for high piers and long-distance slippage through scene parameters before construction is essentially a data-driven risk prediction: first, core parameters are accurately collected through detection units; then, risks are located based on preset parameter thresholds and risk point mapping rules; and finally, risk pre-control is achieved through level determination and concrete measures. This process requires the support of a database of construction scene-slippage parameter mapping models to ensure that parameter thresholds and risk mechanisms are derived from engineering practice, avoiding a disconnect between theory and practice, and ultimately achieving the safety goal of "identifying and controlling risks before construction." The specific construction process of the construction scenario and slip parameter mapping model includes: A scenario and parameter dataset is constructed by collecting historical engineering case data and conducting scenario variable control experiments. The historical engineering case data includes construction scenario parameters, slip parameters, and construction effects under different scenarios. The scenario variable control experiments are used to obtain device-specific data to compensate for data deviations caused by device differences in historical cases. The model is constructed to establish a quantitative mapping relationship between scenarios and parameters through scenario clustering and parameter regression analysis; the construction scenarios are classified according to risk level and core variables using a multi-dimensional hierarchical clustering method; the correlation between scenario indicators and slip parameters is analyzed using multiple linear regression or machine learning algorithms to form a quantitative mapping formula or decision rule between scenarios and parameters. Threshold setting and dynamic optimization: Combine engineering specifications and construction feedback to set parameter thresholds to ensure construction accuracy and stability; in actual construction, the detection unit collects construction scene and sliding effect data in real time, compares the deviation between the model output parameters and the actual optimal parameters, iteratively corrects the model, and adapts it to new scenarios and new requirements.

[0034] Model validation involves embedding the constructed mapping model into the construction decision-making system and verifying the model's effectiveness through engineering pilot projects. System Integration: The model code is written into the construction decision module, the detection unit, and the remote controller for linkage. Before construction, the detection unit automatically collects data such as beam span and formwork weight, inputs it into the model, and the model outputs parameters such as track splicing density and traction speed in real time, directly guiding construction preparation.

[0035] Pilot project verification: Apply the model in 1-2 complete high-speed railway cast-in-place box girder projects and compare the construction effects of "model recommended parameters" and "traditional experience parameters"—for example, whether the template damage rate is reduced, the positioning accuracy is improved, and the construction efficiency is increased after the application of the statistical model. If the expectations are met, the model will be promoted; if there are deviations, the model construction process will be returned to supplement data and optimize the model.

[0036] After the model is optimized, the input construction scenarios include: beam span length, formwork weight, site flatness, ambient wind speed, and construction scenario type; the sliding parameters output by the mapping model include: track splicing density, initial traction speed, formwork fastening method, and locking structure parameters. Example 1: Assembly of Device Structure Sliding track system assembly: Multiple sections of I20 I-beams are laid out and spliced ​​according to the construction plan path. The I-beams are rigidly fixed to the cast-in-place support with high-strength bolts. The flatness error at the splicing point is controlled within 1mm to ensure that the track extension direction is consistent with the construction plan path. Template fixing platform 1 assembly: A rectangular frame is formed by 22 channel steels. The diagonal of the rectangular frame and the adjacent 22 channel steels are reinforced by 10 channel steels. A 14mm steel plate is welded to the top of the frame. Roller assembly 3 is installed at the bottom, and roller assembly 3 matches the upper flange of I20 I-beam. Adjustable template rollers 2 are installed at the top. The roller spacing is preset according to the template size to ensure smooth lateral movement of the template. Traction system installation: A 5-ton winch is fixed on the top of the end pier of the target span and connected to the template fixing platform 1 via a steel wire rope, ensuring that the steel wire rope and the sliding track system are coaxial; a handheld remote controller is configured, and the traction speed adjustment range is set to 0.3-0.8m / min; Detection unit installation: Two distance sensors are symmetrically arranged on the tops of the piers at both ends of the cast-in-place support, and one is installed on the crossbeam at the end of the formwork fixing platform 1; weight sensors are installed at the four bearing support points at the top of the formwork fixing platform 1; three flatness sensors are respectively installed at the beginning, middle, and end sides of the sliding track system; wind speed sensors are installed at an unobstructed position on the top of the cast-in-place support; the detection unit is encapsulated in a waterproof and dustproof metal box and connected to each sensor via waterproof cables; Installation of the slippage monitoring unit: The velocity sensor is installed at the end of the roller group 3 at the bottom of the template fixing platform 1; two displacement sensors are installed along the slippage direction on the top edge of the template, and matching receiving components are installed on the corresponding side of the track; two strain sensors are symmetrically arranged at the web position of each I-beam track splice, and two are installed on the diagonal channel steel of the rectangular frame of the template fixing platform 1; the tilt sensor is installed at the top center of the template fixing platform 1; the real-time data transmission module is encapsulated in a waterproof and dustproof metal box and is connected to each sensor via cables; Closed-loop adjustment module installation: The data acquisition module of the detection unit and the data transmission module of the slip condition monitoring unit are encapsulated together in a waterproof and dustproof metal box and fixed to the inner side of the 22 channel steel of the template fixing platform 1 with bolts; the closed-loop adjustment module is connected to the slip condition monitoring unit via RS485 bus, to the detection unit via Ethernet, and to the remote controller via Bluetooth or Wi-Fi; it is connected to the winch via control cable, to the adjustable template roller 2 via PLC control line, to the braking device via emergency control line, and to the audible and visual alarm device via LoRa wireless communication protocol; Auxiliary system installation: A template support lifting mechanism is installed on the top of the template fixing platform 1, and a braking device is installed at the bottom; the controller is electrically connected to the detection unit and closed-loop adjustment module to complete the overall device assembly. The template support lifting mechanism is a hydraulic lifting rod, and the braking device is a caliper brake; Example 2: Application of Construction Method Taking the construction of a 32m standard span cast-in-place box girder as an example, the construction method of this invention includes the following steps: S1: Parameter matching: The detection unit obtains the beam span length of 32m, the template weight of 4.5t, the site flatness error of 1.2mm / m, and the ambient wind speed of 2.5m / s. The controller outputs based on the mapping model: the track splicing density is every 6m, the initial traction speed is 0.5m / min, and the bolt spacing is 30cm. S2: Track laying and positioning: I20 I-beams are spliced ​​in 6m sections and fixed to the cast-in-place supports with expansion bolts. The straightness of the track is calibrated by laser positioning, and the deviation is controlled within 2mm. A winch is fixed on the top of the adjacent span pier, and the tension of the wire rope is adjusted to ensure that the coaxiality error with the track is ≤1mm. S3: Template Installation and Fastening: The hoisting equipment lowers the template to the top surface of the template fixing platform 1. The template support lifting mechanism is operated to lower the template to the bearing surface. The adjustable template roller 2 drives the template to move laterally by 20cm, so that the template is separated from the concrete surface of the beam by a distance of ≥5cm. M24 high-strength bolts are used to fasten the template to the platform. The bolt tightening torque is automatically determined by an automatic ratchet wrench. S4: Sliding Propulsion Control: Release the brake device and start the winch via the remote controller to slide at a speed of 0.5m / min; drive the bottom roller group of the template fixing platform to slide in a straight line along the I20 I-beam rail; the single sliding stroke is controlled between 3 and 9m, and the sliding status monitoring unit monitors in real time. When the horizontal deviation of the template is detected to be 1.8mm, which does not exceed the preset threshold of 2mm, no adjustment is required; when the wind speed rises instantaneously to 5m / s, the monitoring unit triggers an early warning, and the closed-loop adjustment module automatically reduces the traction speed to 0.3m / min; output traction force at the preset speed, and monitor the coordination status between the rail and the template fixing platform 1 in real time during the sliding process; S5: Position Correction and Locking: When the template slides to the target construction position, a three-level alignment and multi-locking positioning mechanism is adopted to achieve precise fixation of the template and the bottom formwork. The first-level alignment uses laser positioning equipment to detect the overall extension direction of the track and the straightness of the joints of each section of the I-beams. If the track path is detected to be off or the joints are misaligned, the bottom support of the track and the fasteners between the track and the cast-in-place support are adjusted to ensure that the deviation between the track extension direction and the construction planning path is within the preset value and that the track joints are flat and without misalignment. The second-level alignment uses a real-time sliding state monitoring unit to collect horizontal offset data during the template sliding process and dynamically corrects the sliding amount based on the horizontal offset data. The third-level alignment uses the lifting adjustment of the template support lifting mechanism to match the vertical elevation of the template with the preset elevation of the bottom formwork. The multiple locking mechanisms are as follows: primary locking locks the relative position of the platform and the track through a braking device; secondary locking connects the template and the bottom mold through fasteners, with the fastening torque of the fasteners automatically determined by an automatic ratchet wrench; and tertiary locking fixes the side of the template and the cast-in-place support through side auxiliary support components.

[0037] S6: Cyclic relocation operation: After the concrete has been poured and cured for 7 days and the strength has reached 85% of the design strength, loosen the bolts and auxiliary support components, and the formwork support lifting mechanism will lower the formwork back to the top of the platform. Repeat steps S3 to S5 to carry out the next span of formwork sliding construction. Safety precautions: Before construction, the structural strength of the track connection was checked and the track support on the high pier side was reinforced; during the sliding process, the winch load was monitored to suddenly rise to 5.2t, while the preset threshold was 5t. The closed-loop adjustment module automatically alarmed and suspended construction. It was found that there was debris at the track splicing point. After cleaning, construction resumed.

[0038] In this embodiment, the formwork was undamaged during construction, the positioning accuracy was 0.8mm, the construction efficiency was increased by 35% compared with traditional hoisting, and the construction cost per span was reduced by 20%.

[0039] It is worth noting that this application solves the technical pain points in traditional cast-in-place box girder formwork construction, such as high labor intensity, low construction efficiency, serious formwork damage, insufficient positioning accuracy, poor scene adaptability, low reuse rate, and prominent safety hazards, through the collaborative design of components such as sliding track system, formwork fixing platform 1, traction system, detection unit, sliding status monitoring unit and closed-loop adjustment module, as well as the setting of construction scene and sliding parameter mapping model, three-level alignment and multi-locking positioning mechanism and safety guarantee active unit. It achieves the construction goals of mechanization, high precision, high adaptability and safety and stability. Specifically, (1) this application constructs a mechanized sliding system through the collaborative operation mechanism of "sliding track system - formwork fixing platform 1 - traction system", which fundamentally changes the traditional construction mode. The sliding track system adopts a multi-segment I20 I-beam detachable splicing design, providing stable guiding support for formwork sliding. The roller group 3 at the bottom of the formwork fixing platform 1 converts sliding friction into rolling friction, significantly reducing sliding resistance. The traction system is equipped with a 5-ton winch and a remote controller, enabling stable output of traction force and remote control. Construction personnel only need to use a handheld terminal to complete operations such as starting and stopping the formwork sliding and adjusting the speed, without needing close contact with the formwork or frequent coordination of hoisting equipment. This mechanized operation mode simplifies the formwork relocation process, which originally required more than 10 people, to be completed by 2-3 people, reducing labor intensity by more than 70%. At the same time, the formwork and the formwork fixing platform 1 form a rigid whole and slide synchronously, avoiding tedious steps such as repeated lifting and alignment during hoisting. The relocation time of a single span formwork is shortened from 4-6 hours in traditional construction to 1-2 hours, improving construction efficiency by more than 30%. It is especially suitable for the needs of large-scale continuous construction of cast-in-place box girders for high-speed railways, effectively shortening the overall project period.

[0040] (2) This application has made multiple optimization designs for this problem: the template fixing platform 1 adopts an integrated structure of 14mm steel plate, 22 channel steel and 10 channel steel. The frame is reinforced by diagonal and transverse 10 channel steel to ensure that the structural strength meets the template bearing requirements and avoids uneven stress on the template due to platform deformation; the adjustable template roller 2 at the top can realize the transverse translation and fine adjustment of the template, so that the template is completely separated from the concrete surface of the beam before sliding, avoiding wear caused by friction between the template and the concrete surface during the sliding process; the design of the roller group 3 and the upper flange of the I20 I-beam rolling cooperation transforms sliding friction into rolling friction, which not only reduces the sliding resistance, but also reduces the hard impact between the template and the supporting structure, and the template damage rate is reduced from 20%-30% in traditional construction to less than 5%. Meanwhile, the core components of the device all adopt a detachable splicing structure. The sliding track system can adjust the number and spacing of I-beam splices according to the beam span length. The template fixing platform 1 is adapted to templates of different sizes and types through adjustable template rollers 2 and template support lifting mechanism, realizing construction adaptation for various scenarios such as 32m standard beam span and 48m large span beam. The equipment reuse rate is increased to more than 85%, which greatly reduces the cost of equipment procurement and replacement and improves the economic efficiency of the project.

[0041] (3) This application has constructed a high-precision positioning and control system through multiple technological innovations, which completely solves the pain point of insufficient positioning accuracy. First, the detection unit collects multi-dimensional construction scenario parameters such as beam span length, template weight, and site flatness. The controller automatically matches key parameters such as track splicing density and initial traction speed based on the construction scenario and sliding parameter mapping model, laying the foundation for precise construction. Second, the sliding state monitoring unit monitors the sliding speed, template offset, track strain value and other state parameters in real time. The sampling frequency is ≥10Hz and the measurement accuracy is ±0.1mm, ensuring dynamic capture of small deviations in the sliding process. The closed-loop adjustment module and the sliding state monitoring unit form a closed-loop control. When the monitored parameters exceed the threshold, the horizontal offset is compensated by fine-tuning the winch traction force distribution and controlling the adjustable template roller 2, so as to avoid the accumulation of deviations. Building upon this foundation, step S5 employs a three-level alignment and multi-locking positioning mechanism. The first-level alignment uses laser positioning to calibrate the track path accuracy; the second-level alignment corrects slippage using dynamic monitoring data; and the third-level alignment achieves precise vertical elevation matching through a template support lifting mechanism, ensuring high-precision alignment between the template and the bottom formwork in three-dimensional space. The multi-locking mechanism utilizes layered protection—platform-track locking, rigid template-bottom formwork fastening, and lateral fixation of the side-support—to ensure stable and displacement-free template positioning. Through the synergistic effect of these technologies, the template positioning deviation in this application can be controlled within 3mm, and in some scenarios, even reaches an ultra-high precision of 0.8mm, fully meeting the stringent requirements for construction quality in high-speed railways and other projects, effectively improving the structural accuracy and durability of the cast-in-place box girder.

[0042] (4) This application comprehensively improves scenario adaptability and construction safety through dynamic adaptation of construction scenarios and sliding parameters and proactive design of safety assurance. The construction scenario and sliding parameter mapping model takes beam span length, formwork weight, site flatness, ambient wind speed and construction scenario type as input parameters, and outputs adaptation parameters such as track splicing density, initial traction speed and formwork fastening method. For example, in the construction of a 48m long span beam, the track splicing density is automatically increased and the initial traction speed is reduced; in a windy environment with wind speed ≥6m / s, the structural parameters are adjusted and locked and the number of side auxiliary support components is increased to achieve accurate adaptation under different scenarios, thus solving the drawback of poor adaptability of traditional construction scenarios. In terms of safety, before construction, safety risks in key scenarios such as high-pier construction and long-distance sliding are identified and predicted through scene parameter identification. Structural strength is reinforced for critical components such as track connections and formwork fixing platform 1. During sliding, the sliding status monitoring and detection units monitor safety parameters in real time, including winch load, bolt tightness, track-support connection stability, and ambient wind speed, with preset normal thresholds for each parameter. When any parameter exceeds the threshold, the closed-loop adjustment module immediately triggers an alarm and suspends sliding construction. Simultaneously, the emergency control line drives the braking device to lock formwork fixing platform 1, preventing the escalation of safety accidents. Furthermore, the closed-loop adjustment module is encapsulated in an IP65-rated waterproof and dustproof metal box, equipped with a backup lithium battery for power redundancy, and the critical control links adopt a redundant design of "wired as primary, wireless backup," ensuring stable operation of the equipment in harsh construction site environments and further enhancing construction safety. Through the above design, this application can maintain stable construction in complex and risky scenarios such as high piers ≥30m, strong wind speeds ≥6m / s, and large spans ≥48m, reducing the accident rate to zero and completely solving the problem of prominent safety hazards in traditional construction.

[0043] In summary, this application solves various technical pain points in the traditional cast-in-place box girder formwork construction, and achieves multiple technical effects such as reduced labor intensity, improved construction efficiency, reduced formwork damage, improved positioning accuracy, enhanced scenario adaptability, and guaranteed construction safety.

[0044] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the protection scope of the present invention.

Claims

1. A sliding device for cast-in-place box girder formwork, characterized in that, include: A sliding track system, which is composed of multiple detachable and spliced ​​sections of I-beams, is used to provide guiding support for the sliding of the template; A template fixing platform is located at the top of the sliding track system. The template fixing platform is an integrated frame structure. The bottom of the template fixing platform is equipped with a roller group that matches the sliding track system. The top of the template fixing platform is equipped with an adjustable template roller for bearing and driving the template to slide synchronously. A traction system, connected to the template fixing platform, includes a winch, a wire rope, and a remote controller, used to pull the template fixing platform along the sliding track system.

2. The apparatus according to claim 1, characterized in that, It also includes a detection unit and a controller; The detection unit is used to acquire construction scene parameters; The controller is electrically connected to the detection unit and has a built-in preset construction scenario and sliding parameter mapping model, which is used to automatically match the sliding parameters based on the construction scenario parameters.

3. The apparatus according to claim 2, characterized in that, It also includes a template fulcrum lifting mechanism and a braking device, located at the top and bottom of the template fixing platform, respectively. The braking device is used to lock the template fixing platform on the sliding track system, and the template fulcrum lifting mechanism is used to lift the template to adjust its vertical height.

4. The apparatus according to claim 3, characterized in that, It also includes a slip condition monitoring unit and a closed-loop adjustment module; The slip state monitoring unit is used to monitor at least one parameter among slip speed, track deformation, template offset and template fixing platform tilt angle, and is connected to the remote controller of the traction system through the closed-loop adjustment module to form closed-loop control. The closed-loop adjustment module is installed inside the side channel steel frame of the template fixing platform. The input end of the closed-loop adjustment module is connected to the sliding state monitoring unit, the detection unit and the remote controller. The output end of the closed-loop adjustment module is connected to the adjustable template roller and the braking device. The output end of the closed-loop adjustment module is also connected to an audible and visual alarm device, thus forming a closed-loop control system.

5. A method for slip-fitting formwork construction of cast-in-place box girder based on the device described in claim 4, characterized in that, Includes the following steps: S1. Obtain construction scene parameters through the detection unit, and automatically match the construction parameters of the track based on the preset construction scene and sliding parameter mapping model; S2. Lay the sliding track system on the top surface of the cast-in-place support according to the construction plan path; fix the traction system at the preset position on the top of the pier at the end of the next span of the cast-in-place beam, so that the traction system and the sliding track system are coaxial. S3. Lower the template to the top of the template fixing platform, operate the template support lifting mechanism to lower the template to the preset bearing surface, drive the template to move laterally through the adjustable template rollers at the top of the template fixing platform, so that the template is completely separated from the concrete surface of the beam; fasten the template to the template fixing platform to form a rigid whole that slides synchronously. S4. The traction system outputs traction force at a preset speed to pull the template fixing platform carrying the template to slide along the track. During the sliding process, the cooperation status between the track and the template fixing platform is monitored in real time. S5. When the template slides to the target construction position, a three-level alignment and multiple locking positioning mechanism is adopted to achieve precise fixing of the template and the bottom formwork; S6. After the concrete is poured and the strength reaches the preset value, loosen the connection between the formwork and the bottom formwork, and use the formwork support lifting mechanism to lower the formwork back to the top surface of the formwork fixing platform. Repeat steps S3 to S5 to realize the cyclic sliding use of the formwork.

6. The construction method according to claim 5, characterized in that, During the sliding process in step S4, the sliding state parameters are monitored in real time by the sliding state monitoring unit. Sliding stable state parameters are constructed based on the mechanical balance mechanism, and a stable threshold range is preset. When the state parameters exceed the threshold, the control mechanism is automatically activated. The winch traction force distribution is finely adjusted by the remote controller, and the adjustable template rollers on the top of the template fixing platform are driven to compensate for the horizontal offset of the template.

7. The construction method according to claim 5, characterized in that, A three-level alignment and multi-locking positioning mechanism is adopted. The three-level alignment is as follows: Level 1 alignment uses laser positioning equipment to detect the straightness of the overall extension direction of the track and the splicing points of each I-beam. If track path deviation or splicing misalignment is detected, the deviation between the track extension direction and the planned construction path is kept within a preset value by adjusting the bottom support of the track and tightening the fasteners between the track and the cast-in-place support, and the track splicing points are flat and without misalignment. Level 2 alignment uses a real-time sliding state monitoring unit to collect horizontal offset data during the sliding process of the template, and dynamically corrects the sliding amount based on the horizontal offset data. Level 3 alignment uses the lifting and lowering adjustment of the template support lifting mechanism to match the vertical elevation of the template with the preset elevation of the bottom formwork. The multiple locking mechanisms are as follows: the primary locking mechanism locks the relative position of the template fixing platform and the track through a braking device; The secondary locking system connects the template and the bottom mold with fasteners, and the tightening torque of the fasteners is automatically determined by an automatic ratchet wrench; the tertiary locking system fixes the sides of the template and the cast-in-place support with side auxiliary supports.

8. The construction method according to claim 5, characterized in that, It also includes an active security unit, specifically including: Before construction, based on the construction scenario parameters obtained by the detection unit, the safety risk points of high pier construction and long-distance sliding scenarios are predicted, and the structural strength of the device parts corresponding to the safety risk points is strengthened. During the sliding advance process in step S4, safety parameters are monitored in real time. These parameters include winch load, bolt tightness, connection stability between the track and the cast-in-place support, and ambient wind speed. Normal thresholds for each safety parameter are preset. When any safety parameter is detected to exceed the normal threshold, the closed-loop adjustment module automatically triggers an alarm and suspends the sliding construction. The sliding advance process in step S4 is resumed after the hidden danger is eliminated.

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