Steel bar system conversion equipment suitable for open-cut cast-in-place arch structure and construction method

Abstract

The invention discloses steel bar system conversion equipment suitable for an open-cut cast-in-place arch structure and a construction method.The equipment comprises a cantilever gantry crane, a servo system arranged on the cantilever gantry crane and a plurality of lifting ropes controlled to stretch out and draw back through the servo system, the cantilever gantry crane is located over a foundation pit, and a walking system is arranged at the bottom of the cantilever gantry crane; the cantilever gantry crane longitudinally moves along a foundation pit, the multiple lifting ropes are arranged in the transverse direction and the longitudinal direction of the cantilever gantry crane and vertically and downwards connected to different positions of a reinforcement cage bound on the reinforcement trolley to form distributed lifting points, the lifting ropes are controlled by the servo system to apply prestress to the reinforcement cage to a preset value, and deformation of the reinforcement cage is controlled. Deformation of the reinforcement cage can be limited, streamlined operation of the open-cut cast-in-place structure is achieved, and the construction efficiency is improved.

Description

Technical Field

[0001] This invention relates to the fields of tunnel engineering and municipal engineering technology. More specifically, this invention relates to a steel reinforcement system conversion device and construction method suitable for open-cut cast-in-place arch structures. Background Technology

[0002] Open-cut cast-in-place construction, a common method in underground engineering, primarily involves rebar tying and formwork concrete pouring. The main construction methods are scaffolding or formwork trolleys. Scaffolding construction carries high safety risks. There are two types of formwork trolleys: rebar trolleys for tying rebar and formwork trolleys for pouring concrete. After the rebar is tied on the rebar trolley, it needs to be removed from the current rebar cage to allow the formwork trolley to enter. However, if the rebar is not supported after tying, the rebar cage will deform under gravity, causing plastic deformation or hindering the formwork trolley from entering. Therefore, rebar trolleys are often used to tie the side wall rebar, while formwork trolleys are used to tie the arch rebar. Thus, a device and construction method are needed to limit the deformation of the rebar cage after the rebar trolley is removed from the current rebar cage, allowing for a smooth transfer of the rebar cage from the rebar trolley to the formwork trolley. Summary of the Invention

[0003] One objective of this invention is to provide a steel reinforcement system conversion device and construction method suitable for open-cut cast-in-place arch structures. This device can limit the deformation of the steel reinforcement cage and solve the problem that after the steel reinforcement trolley is tied with steel reinforcement, the steel reinforcement cage is deformed under gravity after the steel reinforcement trolley leaves the current steel reinforcement cage, resulting in plastic deformation of the steel reinforcement cage or hindering the formwork trolley from entering the current steel reinforcement cage.

[0004] To address the aforementioned technical problems, this invention provides a rebar system conversion device suitable for open-cut cast-in-place arch structures, comprising a cantilever gantry crane, a servo system mounted on the cantilever gantry crane, and multiple lifting ropes controlled by the servo system for extension and retraction. The cantilever gantry crane is located directly above the foundation pit and has a traveling system at its bottom, moving longitudinally along the foundation pit. The multiple lifting ropes are arranged laterally and longitudinally along the cantilever gantry crane and vertically downwards connected to different positions of the rebar cage tied on the rebar trolley to form distributed lifting points. The servo system controls the lifting ropes to apply prestress to the rebar cage to a preset value, controlling the deformation of the rebar cage.

[0005] Preferably, the steel cage consists of two layers of curved steel bars, with support bars set at predetermined positions on both layers, and distributed lifting points fixed to the positions of the support bars of the inner layer of curved steel bars.

[0006] Preferably, the distributed lifting points are symmetrically spaced along the tunnel's central axis within the tunnel's circumferential cross-section, and multiple distributed lifting points are spaced longitudinally within the circumferential cross-section.

[0007] Preferably, the hoisting rope is prestressed by a through-hole jack, which is controlled by a servo system. The hoisting rope is also equipped with a tension sensor, which is used to acquire the tension of the hoisting rope and transmit it to the servo system.

[0008] This invention also provides a method for converting the reinforcement system of a cast-in-place arch structure in open excavation, comprising the following steps: Step 1: Calculate and analyze to obtain the location of the distributed lifting points of the steel cage, the number of distributed lifting points, and the prestress of each lifting rope; Step 2: The rebar trolley is positioned at the designated location, and the rebar is hoisted onto the rebar trolley; Step 3: Tie the reinforcing bars on the reinforcing bar trolley and set up support bars between the inner and outer layers of curved reinforcing bars; Step 4: Install the cantilever gantry crane, servo system and lifting rope at the set position on the foundation pit, and arrange distributed lifting points according to the set position and number of lifting points. At the same time, use the servo motor to prestress the lifting rope to the set value, and input the displacement value at this time into the servo system. When the displacement value changes, the servo system controls the lifting rope to pull to the preset value and controls the deformation of the steel cage. Step 5: Move the rebar trolley out to the current rebar cage, move the formwork trolley into the current rebar cage, release the prestress on the lifting ropes, so that the rebar cage is attached to the formwork platform, and complete the rebar cage system conversion.

[0009] Preferably, in step one, the calculation and analysis process specifically includes: Step S1: Model the steel reinforcement cage; Step S2: Apply load to the overall model and adjust the location and number of distributed lifting points. Obtain the deformation cloud map by calculation, and then adjust the location and number of lifting points to minimize the deformation of the steel cage, thereby obtaining the optimal range of the location and number of distributed lifting points. Step S3: Adjust the tension of the distributed lifting points according to the weight of the steel cage, obtain the deformation cloud map by calculation, and then fine-tune the distribution of the tension of the distributed lifting points to minimize the deformation of the steel cage, and obtain the prestress of each lifting rope corresponding to the distributed lifting points.

[0010] Preferably, in step S1, only the circumferential and longitudinal reinforcement bars are modeled during the modeling and calculation; the stirrups are not modeled, and the weight of the stirrups is converted into the density of the reinforcement. In the formula ρ 0 This represents the actual density of the reinforcing steel. ρ To calculate density, m 0 This refers to the overall weight of the steel cage. mThe weight of the reinforcing cage does not include the stirrups; the circumferential reinforcement, longitudinal reinforcement, and stirrups are all modeled using beam elements. The circumferential and longitudinal reinforcements are hinged, the inner second row of double-layer reinforcement is hinged to the longitudinal reinforcement, and the stirrups are rigidly connected to the inner and outer reinforcements; the constraint of the pit sidewall on the reinforcing cage is an elastic horizontal support, simulated using nonlinear springs, with the spring stiffness... k As shown in the following formula, In the formula, l 0 The distance between the side of the reinforcing cage and the side wall of the foundation pit; the bottom of the reinforcing cage is fully constrained, and the vertical support is rigid.

[0011] Preferably, in step S2, gravity is applied to the overall model, and only the displacement in the direction of gravity is constrained at the lifting points; four lifting points are arranged in cross sections, rotated at two different angles along the tunnel centerline, and arranged symmetrically; at the same time, the lifting points are arranged at intervals along the longitudinal direction, and the longitudinal spacing of the lifting points is adjusted by the deformation cloud map obtained by calculation, so that the deformation of the steel cage is minimized.

[0012] Preferably, in step S3, the total tension at the lifting points is set as a certain proportion of the weight of the steel cage; and the prestress of the two rows of lifting points near the centerline of the tunnel is set as a certain proportion of the total tension at the lifting points, while the prestress of the other two rows of lifting points is set as the remaining proportion of the total tension at the lifting points; the proportion of the lifting point tension is finely adjusted by the calculated deformation cloud map to minimize the deformation of the steel cage.

[0013] Preferably, the deformation measurement of the reinforcing cage is carried out by setting multiple cross sections, and setting multiple deformation measuring points in each cross section. Multiple deformation measuring points are set at intervals along the circumference of the cross section, and the deformation is obtained by taking the average value of multiple cross sections. The deformation is set within a certain range.

[0014] The present invention has at least the following beneficial effects: (1) Compared with tying the arch reinforcement on the template trolley, the present invention uses a reinforcement system conversion equipment to separate the reinforcement tying process and the concrete pouring process, realize the assembly line operation of open-cut cast-in-place structure, and improve construction efficiency.

[0015] (2) Compared with conventional steel bar trolleys, the present invention uses a steel bar system conversion equipment to enable the simultaneous binding of side wall steel bars and arch top steel bars on the steel bar trolley. A tension sensor is installed on the lifting rope, and a servo system is installed at the end of the lifting rope to automatically compare the actual lifting rope tension, steel cage deformation and theoretical deviation. The lifting rope tension is controlled by the servo system to avoid the steel cage from deforming downwards after leaving the steel bar trolley, thus ensuring the quality of the project.

[0016] (3) Compared with conventional cast-in-place reinforced concrete construction, this invention does not require cranes for hoisting operations, avoids cranes occupying lanes, and optimizes construction organization.

[0017] Other advantages, objectives and features of the present invention will become apparent in part from the following description, and in part from those skilled in the art through study and practice of the invention. Attached Figure Description

[0018] Figure 1 This is a flowchart of the construction process of the present invention; Figure 2 This is a schematic diagram of the structure of the present invention, showing the rebar trolley being moved to the bottom of the formwork trolley; Figure 3 This is a schematic diagram of the structure of the steel reinforcement system conversion device of the present invention for hoisting steel reinforcement; Figure 4 This is a schematic diagram of the rib arrangement structure of the present invention; Figure 5 This is a schematic diagram of the structure of the steel bar trolley detaching from the steel bar cage according to the present invention; Figure 6 This is a schematic diagram of the structure of the template trolley entering the steel cage and disassembling the distributed lifting points according to the present invention; Figure 7 This is a diagram showing the arrangement of deformation measurement points and support points for this invention. Detailed Implementation

[0019] To better understand the purpose, structure, and function of this invention, the invention will be further described in detail below with reference to the accompanying drawings, so that those skilled in the art can implement it based on the description.

[0020] It should be noted that, unless otherwise specified, the experimental methods described in the following embodiments are all conventional methods, and the reagents and materials described are all commercially available unless otherwise specified. In the description of this invention, the terms "lateral", "longitudinal", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", and "outer" indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are only for the convenience of describing this invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on this invention.

[0021] like Figure 2 , Figure 3 and Figure 5As shown, the present invention provides a steel reinforcement system conversion equipment suitable for open-cut cast-in-place arch structures, including a cantilever gantry crane 1, a servo system 2 installed on the cantilever gantry crane, and multiple lifting ropes 3 controlled by the servo system to extend and retract. The cantilever gantry crane is located directly above the foundation pit and has a traveling system at its bottom, which moves longitudinally along the foundation pit. The multiple lifting ropes are arranged laterally and longitudinally along the cantilever gantry crane and vertically connected to different positions of the steel reinforcement cage tied on the steel reinforcement trolley 4 to form distributed lifting points 7. The servo system controls the lifting ropes to apply prestress to the steel reinforcement cage to a preset value, thereby controlling the deformation of the steel reinforcement cage.

[0022] The steel cage consists of two layers of arc-shaped steel bars 5, with support bars 6 set at designated positions on both layers. Distributed lifting points are fixed to the positions of the support bars of the inner layer of arc-shaped steel bars.

[0023] Distributed lifting points are symmetrically spaced along the tunnel's central axis within the tunnel's circumferential cross-section, and multiple distributed lifting points are also spaced longitudinally within the tunnel's circumferential cross-section.

[0024] The hoisting rope is prestressed by a through-hole jack, which is controlled by a servo system. The hoisting rope is also equipped with a tension sensor, which is used to acquire the tension of the hoisting rope and transmit it to the servo system.

[0025] The rebar system conversion device of this application is movable above the foundation pit. This device is equipped with a cantilever gantry crane and distributed lifting points. When the rebar cage is being tied on the rebar trolley, the rebar system conversion device is positioned directly above the rebar cage via a travel system. The cantilever gantry crane of the rebar system conversion device lifts the rebar from the outside of the foundation pit onto the rebar trolley. While the rebar is being tied on the rebar trolley, the upper and lower layers of curved rebar are positioned with support bars at designated locations. After the rebar cage is tied, the distributed lifting points are fixed to the positions of the inner layer of curved rebar support bars. The distributed lifting points include a servo system for automatically controlling the lifting ropes, and the prestress of the distributed lifting points is determined through modeling calculations. After the force of the distributed lifting points is applied to the designated prestress, the rebar trolley moves out of the current rebar cage, and the deformation of the rebar cage is precisely controlled by the servo system. The formwork trolley 8 travels to the bottom of the current rebar cage to support it, releases the distributed lifting points, and completes the conversion of the rebar cage from the rebar trolley to the formwork trolley. This invention, through a steel reinforcement system conversion device and its construction method, avoids the impact of deformation on subsequent construction caused by tying steel reinforcement on the formwork trolley or by the steel reinforcement cage detaching from the steel reinforcement trolley, compared to conventional construction.

[0026] This invention utilizes a rebar system conversion device to transfer the rebar cage from a rebar trolley to a formwork trolley. This invention also provides a rebar system conversion construction method suitable for open-cut cast-in-place arch structures, such as... Figure 1 As shown, it includes the following steps: (1) The location of the distributed lifting points of the steel cage, the number of distributed lifting points, and the prestress of each lifting rope are obtained through calculation and analysis.

[0027] Step S1: Model the steel reinforcement cage; During modeling and calculation, only the circumferential and longitudinal reinforcement are modeled; the stirrups are not modeled. The weight of the stirrups (ties) is converted into the density of the reinforcement. In the formula ρ 0 This represents the actual density of the reinforcing steel. ρ To calculate density, m 0 This refers to the overall weight of the steel cage. m The weight of the reinforcing cage does not include the stirrups; the circumferential reinforcement, longitudinal reinforcement, and stirrups are all modeled using beam elements. The circumferential and longitudinal reinforcements are hinged, the inner second row of double-layer reinforcement is hinged to the longitudinal reinforcement, and the stirrups are rigidly connected to the inner and outer reinforcements; the constraint of the pit sidewall on the reinforcing cage is an elastic horizontal support, simulated using nonlinear springs, with the spring stiffness... k As shown in the following formula, In the formula, l 0 This is the distance between the side of the reinforcing cage and the side wall of the foundation pit; the bottom of the reinforcing cage is fully constrained, and the vertical support is a rigid support.

[0028] In the calculation, the binding between the reinforcing bars is considered a hinged connection, and the welding between the reinforcing bars is considered a rigid connection.

[0029] Step S2: Apply load to the overall model and adjust the location and number of distributed lifting points. Obtain the deformation cloud map by calculation, and then adjust the location and number of lifting points to minimize the deformation of the steel cage, thereby obtaining the optimal range of the location and number of distributed lifting points. Gravity is applied to the overall model, and displacement in the direction of gravity is constrained only at the lifting points. Four lifting points are arranged in the cross section, rotated at two different angles (e.g., 15° and 45°) along the tunnel centerline, and arranged symmetrically. Simultaneously, the lifting points are spaced longitudinally, with a spacing of 2-3 meters. If the longitudinal length of the reinforcing cage is not an integer multiple of 3 meters, it is rounded up. The longitudinal spacing of the lifting points is adjusted using the calculated deformation cloud diagram to minimize the deformation of the reinforcing cage.

[0030] Step S3: Adjust the tension of the distributed lifting points according to the weight of the steel cage, obtain the deformation cloud map by calculation, and then fine-tune the distribution of the tension of the distributed lifting points to minimize the deformation of the steel cage, and obtain the prestress of each lifting rope corresponding to the distributed lifting points.

[0031] The total tension at the lifting points is set as a certain proportion of the weight of the steel cage, such as 60%; and the prestress of the two rows of lifting points closest to the centerline of the tunnel is set as a certain proportion of the total tension at the lifting points, such as 70%, while the prestress of the other two rows of lifting points is set as the remaining proportion of the total tension, such as 30%. The proportion of the tension at the lifting points is finely adjusted by the deformation cloud map obtained from the calculation, so that the deformation of the steel cage is minimized.

[0032] The deformation measurement of the reinforcing cage is carried out by setting up multiple cross sections, and setting multiple deformation measuring points in each cross section. Multiple deformation measuring points are set at intervals along the circumference of the cross section. The deformation is obtained by taking the average value of multiple cross sections, and the deformation is set within a certain range.

[0033] like Figure 7 As shown, measurement points are set up at locations with large displacements and important connections. Three cross-sections—edge, center, and edge—are selected. Targets are placed on the inner ring reinforcement and the adjacent longitudinal reinforcement. A total of 11 deformation measurement points are set up per cross-section, symmetrically arranged. A total station is used to measure the coordinate data of each working condition and compare the deformation. When measuring deformation, a total of 3 cross-sections are measured, and the average value of these 3 cross-sections is taken. This method can also be used to measure the displacement changes in step four.

[0034] (2) For example Figure 2 and Figure 3 As shown, the rebar trolley moves to the current construction section, controls the rebar system conversion device to move longitudinally, and stores the rebar from the transport vehicle longitudinally to the edge of the foundation pit. The cantilever gantry crane in the rebar system conversion device then uses the rebar to orderly lift the rebar from outside the foundation pit onto the rebar trolley.

[0035] (3) such as Figure 4 As shown, reinforcing bars are tied on the reinforcing bar trolley, and stirrups are placed between the inner and outer layers of the curved reinforcing bars. In order to minimize deformation during the hoisting of the reinforcing cage, the stirrups are arranged in five rows around the circumference at angles of 15° and 30°, with a longitudinal spacing of 1.2m to 2m.

[0036] (4) such as Figure 5 As shown, after the steel reinforcement is tied, a cantilever gantry crane, servo system and lifting rope are installed at the set position on the foundation pit. Distributed lifting points are arranged according to the set position and number of lifting points. The end of the distributed lifting points is fixed to the position of the lower arc-shaped steel reinforcement frame, that is, the lifting rope is fixed to the position of the bottom longitudinal bar of the frame.

[0037] (5) Apply pre-tension to the distributed lifting points through the through-hole jack to control the pre-tension to the calculated value. Input the deformation value of the steel cage at the lifting point at this time into the displacement servo system. When the displacement value changes, the servo system controls the lifting rope to pull to the preset value and controls the deformation of the steel cage.

[0038] (6) The steel bar trolley is removed from the steel bar cage, and the deformation of the steel bar cage is controlled by the displacement servo system.

[0039] (7) For example Figure 6 As shown, the rebar trolley is moved to the current rebar cage, the formwork trolley is moved to the bottom of the current rebar cage and supports the rebar cage, the distributed lifting points are released, the pretension on the lifting ropes is released, so that the rebar cage is attached to the formwork platform, and the rebar cage system conversion is completed.

[0040] It is understood that the present invention has been described through some embodiments, and those skilled in the art will recognize that various changes or equivalent substitutions can be made to these features and embodiments without departing from the spirit and scope of the invention. Although embodiments of the present invention have been disclosed above, they are not limited to the applications listed in the specification and embodiments. It can be applied to various fields suitable for the present invention, and other modifications can be easily implemented by those skilled in the art. Therefore, without departing from the general concept defined by the claims and their equivalents, the present invention is not limited to the specific details and examples shown and described herein.

Claims

1. Equipment for converting steel reinforcement systems in open-cut cast-in-place arch structures, characterized in that, The system includes a cantilever gantry crane, a servo system mounted on the cantilever gantry crane, and multiple lifting ropes that are controlled to extend and retract by the servo system. The cantilever gantry crane is located directly above the foundation pit and has a traveling system at its bottom. It moves longitudinally along the foundation pit. The multiple lifting ropes are arranged laterally and longitudinally along the cantilever gantry crane and vertically downwards to form distributed lifting points at different positions on the steel cage tied on the steel rebar trolley. The servo system controls the lifting ropes to apply prestress to the steel cage to a preset value, thereby controlling the deformation of the steel cage.

2. The steel reinforcement system conversion equipment for open-cut cast-in-place arch structures as described in claim 1, characterized in that, The steel cage consists of two layers of curved steel bars, with support bars set at designated positions on both layers. Distributed lifting points are fixed to the positions of the support bars on the inner layer of curved steel bars.

3. The reinforcement system conversion equipment for open-cut cast-in-place arch structures as described in claim 1, characterized in that, Distributed lifting points are symmetrically spaced along the tunnel's central axis within the tunnel's circumferential cross-section, and multiple distributed lifting points are also spaced longitudinally within the tunnel's circumferential cross-section.

4. The reinforcement system conversion equipment for open-cut cast-in-place arch structures as described in claim 3, characterized in that, The hoisting rope is prestressed by a through-hole jack, which is controlled by a servo system. The hoisting rope is also equipped with a tension sensor, which is used to acquire the tension of the hoisting rope and transmit it to the servo system.

5. A method for converting the reinforcement system of a cast-in-place arch structure in open excavation, characterized in that: Includes the following steps: Step 1: Calculate and analyze to obtain the location of the distributed lifting points of the steel cage, the number of distributed lifting points, and the prestress of each lifting rope; Step 2: The rebar trolley is positioned at the designated location, and the rebar is hoisted onto the rebar trolley; Step 3: Tie the reinforcing bars on the reinforcing bar trolley and set up support bars between the inner and outer layers of curved reinforcing bars; Step 4: Install the cantilever gantry crane, servo system and lifting rope at the set position on the foundation pit, and arrange distributed lifting points according to the set position and number of lifting points. At the same time, use the servo motor to prestress the lifting rope to the set value, and input the displacement value at this time into the servo system. When the displacement value changes, the servo system controls the lifting rope to pull to the preset value and controls the deformation of the steel cage. Step 5: Move the rebar trolley out to the current rebar cage, move the formwork trolley into the current rebar cage, release the prestress on the lifting ropes, so that the rebar cage is attached to the formwork platform, and complete the rebar cage system conversion.

6. The method for converting the reinforcement system of a cast-in-place arch structure in open-cut excavation as described in claim 5, characterized in that, In step one, the calculation and analysis process is as follows: Step S1: Model the steel reinforcement cage; Step S2: Apply load to the overall model and adjust the location and number of distributed lifting points. Obtain the deformation cloud map by calculation, and then adjust the location and number of lifting points to minimize the deformation of the steel cage, thereby obtaining the optimal range of the location and number of distributed lifting points. Step S3: Adjust the tension of the distributed lifting points according to the weight of the steel cage, obtain the deformation cloud map by calculation, and then fine-tune the distribution of the tension of the distributed lifting points to minimize the deformation of the steel cage, and obtain the prestress of each lifting rope corresponding to the distributed lifting points.

7. The method for converting the reinforcement system of a cast-in-place arch structure as described in claim 6, characterized in that, In step S1, only the circumferential and longitudinal reinforcement bars are modeled during the modeling and calculation; the stirrups are not modeled, and the weight of the stirrups is converted into the density of the reinforcement. In the formula ρ 0 This represents the actual density of the reinforcing steel. ρ To calculate density, m 0 This refers to the overall weight of the steel cage. m The weight of the reinforcing cage does not include the stirrups; the circumferential reinforcement, longitudinal reinforcement, and stirrups are all modeled using beam elements. The circumferential and longitudinal reinforcements are hinged, the inner second row of double-layer reinforcement is hinged to the longitudinal reinforcement, and the stirrups are rigidly connected to the inner and outer reinforcements; the constraint of the pit sidewall on the reinforcing cage is an elastic horizontal support, simulated using nonlinear springs, with the spring stiffness... k As shown in the following formula, In the formula, l 0 The distance between the side of the reinforcing cage and the side wall of the foundation pit; the bottom of the reinforcing cage is fully constrained, and the vertical support is rigid.

8. The method for converting the reinforcement system of a cast-in-place arch structure as described in claim 6, characterized in that, In step S2, gravity is applied to the overall model, and the displacement in the direction of gravity is constrained only at the lifting points; four lifting points are arranged in cross sections, rotated at two different angles along the tunnel centerline, and arranged symmetrically; at the same time, the lifting points are arranged at intervals along the longitudinal direction, and the longitudinal spacing of the lifting points is adjusted by the deformation cloud map obtained by calculation, so that the deformation of the steel cage is minimized.

9. The method for converting the reinforcement system of a cast-in-place arch structure as described in claim 6, characterized in that, In step S3, the total tension at the lifting points is set as a certain proportion of the weight of the steel cage; and the prestress of the two rows of lifting points closest to the centerline of the tunnel is set as a certain proportion of the total tension at the lifting points, while the prestress of the other two rows of lifting points is set as the remaining proportion of the total tension at the lifting points; the proportion of the tension at the lifting points is finely adjusted by the deformation cloud map obtained by calculation so that the deformation of the steel cage is minimized.

10. The method for converting the reinforcement system of a cast-in-place arch structure in open-cut excavation as described in claim 6, characterized in that, The deformation measurement of the reinforcing cage is carried out by setting up multiple cross sections, and setting multiple deformation measuring points in each cross section. Multiple deformation measuring points are set at intervals along the circumference of the cross section. The deformation is obtained by taking the average value of multiple cross sections, and the deformation is set within a certain range.

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