3D printing lining ground testing device fused with in-situ laying of reinforcing steel bars

Abstract

The invention provides a 3D printing lining ground test device fusing in-situ laying of reinforcing steel bars. The device comprises a stirring and pumping module, a 3D printing lining module, a 3D printing lining mechanical arm, a reinforcing steel bar in-situ laying module, a reinforcing steel bar in-situ laying mechanical arm and a tunnel ring, the 3D printing lining module comprises a spray head, and the reinforcing steel bar in-situ laying module comprises a flexible reinforcing steel bar clamping head and a structured light camera; the stirring and pumping module stirs to prepare a fresh concrete material and pumps the material to the 3D printing lining module, the material pumped to the 3D printing lining module is printed in the tunnel ring through the spray head, and the flexible steel bar clamping head clamps and places a steel bar on the printed concrete. And the structured light camera scans the tunnel section morphology and the surface morphology of the printed lining part, and provides data support for motion planning of the mechanical arm. The method has great application potential in simplifying the lining construction process and efficiently building the long-term stable tunnel.

Description

Technical Field

[0001] The present invention belongs to the field of intelligent manufacturing technology, and in particular relates to a 3D printing lining ground test device integrating in-situ laying of steel bars. Background Art

[0002] Lining is a permanent support structure built with reinforced concrete and other materials along the perimeter of the tunnel in order to prevent deformation or collapse of the surrounding rock during underground construction. The structural stability and mechanical durability of the lining are the prerequisites for the efficient construction of tunnels that can withstand long-term loads and external forces such as earthquake shocks. As a brittle material, plain concrete used to make linings has problems such as easy cracking and poor bending strength. At present, reinforcing materials such as fibers, steel cables, and steel bars are usually introduced in engineering to enhance the mechanical properties of concrete. Compared with fibers and steel cables, steel bars have stronger tensile and bending properties, so reinforced concrete linings have stronger mechanical properties. At present, reinforced concrete linings are mostly prefabricated linings. Before the final support is formed, the lining needs to go through multiple processes such as production, transportation, and assembly. There are still deficiencies in construction costs, construction complexity, and construction quality. In order to optimize the lining construction process, 3D printing concrete technology has been introduced into the project to realize in-situ manufacturing of tunnel linings. The spatial motion curve of the printing module is inversely solved through the target lining size and surface morphology, and then the high-precision and high-quality manufacturing of the lining is achieved by controlling the printing parameters such as the printing module speed, extrusion speed, nozzle diameter, and nozzle height, which greatly shortens the time and space distance from lining production to assembly.

[0003] As tunnel excavation tends to ultra-deep hard rock formations, tunnel linings need to support and maintain tunnel stability and durability for a long time to prevent the lining's ability to bear loads and maintain surrounding rock stability from not matching the surrounding rock pressure, affecting tunnel safety. Although the existing in-situ 3D printing lining method can achieve efficient in-situ production of linings, the hardening differences between different printing layers in the 3D printing process can easily cause "cold joints", which in turn cause insufficient strength of the in-situ 3D printed lining. In addition, this method is currently incompatible with the traditional reinforced lining method of inserting steel cages, making it difficult to manufacture high-strength and high-durability linings. Therefore, intelligent tunnel construction also requires an in-situ 3D printing method for linings with higher strength and high durability. However, due to the different soil and rock characteristics of different tunnels, in order to achieve in-situ 3D printing of linings for specific tunnels, it is necessary to first test and obtain printing parameters such as printing module speed, extrusion speed, nozzle diameter, and nozzle height suitable for the tunnel. At present, the above printing parameters are determined by numerical analysis and other methods, but the field test cycle is long and the cost is high, and it is impossible to carry out research on specific tunnels. Summary of the invention

[0004] In order to solve the problems in the prior art, the present invention proposes a 3D printing lining ground test device integrating in-situ laying of steel bars.

[0005] The technical solution adopted by the present invention is as follows:

[0006] A 3D printing lining ground test device integrating in-situ laying of steel bars, comprising a mixing and pumping module, a 3D printing lining module, a 3D printing lining mechanical arm, an in-situ laying module of steel bars, an in-situ laying mechanical arm of steel bars and a tunnel ring;

[0007] The mixing and pumping module is used to mix and prepare fresh concrete materials, and pump the fresh concrete materials to the 3D printing lining module;

[0008] The 3D printing lining module includes a nozzle installed at the end of the 3D printing lining mechanical arm, the 3D printing lining mechanical arm is used to drive the 3D printing lining module to move, and the 3D printing lining module is used to print fresh concrete materials in the tunnel ring through the nozzle;

[0009] The steel bar in-situ laying module is installed at the end of the steel bar in-situ laying robotic arm, and the steel bar in-situ laying robotic arm is used to drive the steel bar in-situ laying module to move; the steel bar in-situ laying module includes a steel bar clamping head and a structured light camera, the steel bar clamping head is used to clamp and place steel bars, and the structured light camera is used to scan the surface morphology of the inner surface of the tunnel ring and the surface morphology of the printed lining part, so as to provide data support for the motion planning of the 3D printing lining robotic arm and the steel bar in-situ laying robotic arm.

[0010] Based on the above device, the present invention also proposes a 3D printed lining ground test method integrating in-situ laying of steel bars, comprising:

[0011] 1) The in-situ steel bar laying robot drives the structured light camera to scan along the inside of the tunnel ring to generate the inner surface morphology of the tunnel ring. Based on the inner surface morphology of the tunnel ring, the motion trajectory of the 3D printing lining robot and the in-situ steel bar laying robot to manufacture the first layer of the lining is planned;

[0012] 2) The concrete raw materials are fed into the mixing and pumping module, and the mixing and pumping module mixes the concrete raw materials to produce fresh concrete materials;

[0013] 3) The mixing and pumping module pumps the fresh concrete material to the 3D printing lining module, and the 3D printing lining module extrude the fresh concrete material from the nozzle onto the tunnel ring. The 3D printing lining robot arm drives the 3D printing lining module to move according to the plan to print a single layer of lining;

[0014] 4) After the single-layer lining is printed, the in-situ steel bar laying robot arm drives the flexible steel bar clamping head to clamp the steel bars according to the plan, and arranges the clamped steel bars on the printed single-layer lining;

[0015] 5) After completing the steel bar arrangement on a single layer of lining, the steel bar in-situ laying robot arm drives the structured light camera to scan the surface morphology of the currently printed lining part; based on the surface morphology of the printed lining part and the surface morphology of the tunnel ring, the motion trajectory of the 3D printing lining robot arm and the steel bar in-situ laying robot arm to manufacture the next layer of lining is planned;

[0016] 6) Execute steps 3)-5) repeatedly until the printing of the desired lining is completed.

[0017] 7) Carry out performance tests on the tunnel rings with printed lining and evaluate the lining quality based on the performance test results.

[0018] The 3D printed lining ground test device proposed in this invention, which integrates in-situ laying of steel bars, focuses on the core function of tunnel lining construction: stable support. This function mainly relies on the bond strength between steel bars and concrete during the lining manufacturing process to ensure that the lining does not debond or crack under long-term load.

[0019] The present invention has the following advantages:

[0020] (1) The present invention simulates actual working conditions on a smaller scale, thereby greatly reducing the research cost and research cycle of applying 3D printed linings with in-situ laying of fused steel bars in tunnel engineering;

[0021] (2) The present invention is equipped with a flexible steel bar clamping head, which enables the steel bars to be directly arranged between the 3D printed lining layers to enhance the mechanical properties of the lining, solving the problem of incompatibility between the in-situ 3D printing lining method and the traditional reinforced lining method of inserting a steel cage;

[0022] (3) The flexible steel bar clamping head of the present invention supports clamping and arranging steel bars of various diameters, which facilitates the exploration of the mechanical properties of 3D printed linings reinforced with different steel bars;

[0023] (4) The present invention integrates a structured light camera on an in-situ steel bar laying robot arm to scan and generate the tunnel section and the printed filament morphology, and transmits the morphology geometry information to an external control system. The external control system adaptively plans the motion trajectory of the 3D printing lining robot arm and the steel bar in-situ laying robot arm based on the morphology geometry information, thereby realizing online control of the secondary lining printing parameters and the steel bar laying parameters.

[0024] (5) The present invention chooses to integrate the structured light camera on the in-situ steel bar laying robot arm instead of the 3D printing lining robot arm, which can reduce the scanning error caused by the vibration of the 3D printing lining module during the scanning process.

[0025] (6) The present invention has good expansibility and can realize the quick disassembly and replacement of printing components and in-situ steel bar laying components. It is convenient to carry out 3D printing lining research integrated with in-situ steel bar laying by using the newly developed composite nozzle and steel bar clamping head. It has good application prospects in the optimization design of tunnel lining structure stability and the regulation of mechanical properties.

[0026] In summary, the present invention has great application potential in simplifying the lining construction process and efficiently building long-term stable tunnels. BRIEF DESCRIPTION OF THE DRAWINGS

[0027] Figure 1 It is the overall structural diagram of the 3D printed lining ground test device for in-situ laying of fused steel bars of the present invention;

[0028] Figure 2 is a structural diagram of the stirring and pumping module of the present invention;

[0029] Figure 3 is a structural diagram of a 3D printed lining module of the present invention;

[0030] Figure 4 is a cross-sectional view of a 3D printed lining module of the present invention;

[0031] Figure 5 It is a structural diagram of the 3D printing lining mechanical arm of the present invention;

[0032] Figure 6 It is a structural diagram of the steel bar in-situ laying module of the present invention;

[0033] Figure 7 It is a structural diagram of the steel bar in-situ laying mechanical arm of the present invention. DETAILED DESCRIPTION

[0034] The present invention is further described and illustrated below in conjunction with specific embodiments. The embodiments are merely exemplary of the present disclosure and do not define the scope of limitation. The technical features of each embodiment of the present invention may be combined accordingly without conflicting with each other.

[0035] The overall diagram of the designed 3D printed lining ground test device with in-situ laying of fusion steel bars is shown in the figure. Figure 1 It mainly includes a mixing and pumping module 1, a pressure-resistant hose 2, a 3D printing lining module 3, a 3D printing lining mechanical arm 4, a steel bar in-situ laying module 5, a steel bar in-situ laying mechanical arm 6, a workbench 7, and a tunnel ring 8.

[0036] The stirring and pumping module 1 is connected to the 3D printing lining module 3 through a pressure-resistant hose 2. The end of the stirring and pumping module 1 is connected to the pressure-resistant hose 2 through a stainless steel clamp, and the end of the 3D printing lining module 3 is directly connected to the pressure-resistant hose 2 through welding glue. A flange is provided at the end of the 3D printing lining mechanical arm 4, and the 3D printing lining module 3 is threadedly connected to the 3D printing lining mechanical arm 4 through the circumferential threaded holes on the flange at the end of the 3D printing lining mechanical arm 4. A flange is also provided at the end of the in-situ steel bar laying mechanical arm 6, and the in-situ steel bar laying module 5 is threadedly connected to the in-situ steel bar laying mechanical arm 6 through the circumferential threaded holes on the flange at the end of the in-situ steel bar laying mechanical arm 6. The 3D printing lining mechanical arm 4 and the in-situ steel bar laying mechanical arm 6 are both six-degree-of-freedom mechanical arms, which respectively realize the movement control of the 3D printing lining module 3 and the in-situ steel bar laying module 5. Since the six-degree-of-freedom robot has a high degree of freedom, the 3D printing lining module 3 and the in-situ steel bar laying module 5 at its end can realize free movement and angle adjustment within a certain space, so that it is more suitable for the inner surface of the tunnel that needs circumferential spray printing. The tunnel ring 8 is directly fixed on the workbench 7, and the 3D printing lining robot arm 4 and the in-situ steel bar laying robot arm 6 are arranged on both sides of the workbench along the axis of the tunnel ring 8. The 3D printing lining robot arm 4, the workbench 7, and the in-situ steel bar laying robot arm 6 are all connected to the ground with anchor bolts to ensure the stability of the entire ground test device. The inner surface of the tunnel ring simulates the real inner surface of the tunnel lining to be printed. During the printing process, the nozzle axis is always parallel to the tunnel ring normal.

[0037] The structure diagram of the designed stirring pumping module 1 is as follows Figure 2 As shown. It mainly includes a mixer 101, a fiber hose 102, a hose pump 103 and a concrete delivery pump 104. The mixer 101 includes a mixing bin and a mixing structure in the mixing bin; the hose pump 103 is provided with a crimping pipe joint at both ends of the inlet and outlet, the inlet end of the hose pump 103 is connected to the mixing bin of the mixer 101 using a fiber hose 102, and the outlet end of the hose pump 103 is connected to the concrete delivery pump 104 using a fiber hose 102. When in use, the concrete raw material is first put into the mixing bin of the mixer 101, and the mixing structure of the mixer 101 mixes the raw material. After sufficient mixing, the hose pump 103 transfers the freshly mixed concrete in the mixer 101 to the material bin of the concrete delivery pump 104, and the delivery pump of the concrete delivery pump 104 further delivers the concrete in the material bin to the subsequent 3D printing lining module 3.

[0038] The structure diagram of the designed 3D printed lining module 3 is as follows Figure 3 As shown, the cross-sectional view is Figure 4 As shown, the structure diagram of the 3D printing lining robot arm 4 is as follows Figure 5The 3D printing lining module 3 mainly includes a stepper motor 301, a motor support seat 302, a fixed mounting plate 303, a rigid coupling 304, a spiral extrusion rod 305, a hopper 306, a feed port 307, a barrel wall scraper rod 308 and a nozzle 309. The stepper motor 301 is connected to the motor support seat 302 by threads, and its output shaft passes through the fixed mounting plate 303 and is connected to the spiral extrusion rod 305 by a rigid coupling 304; the motor support seat 302, the fixed mounting plate 303 and the hopper 306 are connected by bolts and nuts, and the fixed mounting plate 303 is fixed to the end of the 3D printing lining robot arm 4 through the circumferential threaded holes on the flange of the 3D printing lining robot arm 4; the hopper 306 is cylindrical, and its side opening is used as a feed inlet 307, which is connected to the pressure-resistant hose 2, and the diameter of one end of the hopper 306 gradually decreases to form a hopper outlet; the spiral extrusion rod 305 is installed in the hopper 306, and the spiral extrusion rod 305 is coaxial with the hopper 306. The barrel wall scraper rod 308 is connected to the spiral extrusion rod 305 by welding to scrape off the concrete accumulated on the barrel wall during the 3D printing process; the nozzle 309 is installed at the hopper outlet of the hopper 306 by internal and external thread connection.

[0039] The structural diagram of the designed in-situ steel bar laying module 5 is as follows: Figure 6 As shown, the structure diagram of the steel bar in-situ laying mechanical arm 6 is as follows Figure 7 As shown. The in-situ steel bar laying module 5 mainly includes a flexible steel bar clamping head 501, a structured light camera 502, an air intake device 503, a connecting plate 504, an air pipe 505 and an air pump 506. The flexible steel bar clamping head 501, the structured light camera 502 and the air intake device 503 are all connected to the connecting plate 504 by threads, and the connecting plate 504 is fixed to the end of the in-situ steel bar laying mechanical arm 6 through the circumferential threaded holes on the flange of the in-situ steel bar laying mechanical arm 6. The flexible steel bar clamping head 501 is used to clamp steel bars, and the air intake device 503 is used to control the clamping action of the flexible steel bar clamping head 501. The air intake device 503 is connected to the air pump 506 through the air pipe 505, and the internal air pressure of the air intake device 503 can be adjusted by the air pump 506, thereby controlling the clamping action design, strength and accuracy of the flexible steel bar clamping head 501.

[0040] The specific process of using this device to conduct 3D printing lining test is as follows:

[0041] The in-situ steel bar laying robot arm 6 drives the structured light camera 502 to scan along the inner surface of the tunnel ring to generate the inner surface morphology of the tunnel ring, and adaptively plans the printing process parameters based on the cross-sectional geometric data. Fresh concrete materials are prepared in the mixing and pumping module 1, and the fresh concrete materials are pumped to the feed port 307 of the 3D printing lining module 3 through the pressure-resistant hose 2. The spiral extrusion rod 305 rotates under the drive of the stepper motor 301, and its rotation speed is controlled by the external control system to input a signal to the stepper motor 301. The fresh concrete material is extruded from the nozzle 309 onto the tunnel ring 8, and the end of the 3D printing lining robot arm 4 moves circumferentially along the inner surface of the tunnel ring, and the axis of the nozzle is controlled to be always parallel to the normal line of the tunnel ring. The extruded concrete forms printing filaments along the movement trajectory of the end of the 3D printing lining robot arm 4, and the printing filaments are attached to the inner surface of the tunnel ring to form a single-layer lining. After the single-layer lining is printed, the air pump 506 adjusts the internal air pressure of the air intake device to control the flexible steel bar clamping head 501 to clamp steel bars of different diameters and shapes. The clamped steel bars are arranged on the printed single-layer lining along the motion trajectory of the end of the steel bar in-situ laying robot arm 6. Subsequently, the steel bar in-situ laying robot arm 6 drives the structured light camera 502 to scan along the printed filaments to obtain the surface morphology data of the currently printed lining, and transmits the surface morphology data to the external control system. The external control system adaptively plans the motion trajectory of the 3D printing lining robot arm 4 and the steel bar in-situ laying robot arm 6 based on the surface morphology data, thereby realizing the online control of the secondary lining printing parameters and the steel bar laying parameters, and providing data support for the second layer lining printing. This cycle is repeated many times to complete the efficient manufacturing of steel bar reinforced 3D printed lining.

[0042] After completing the 3D printing of the lining in the tunnel ring, the test personnel can conduct performance tests on the tunnel ring with printed lining and evaluate the lining quality based on the performance test results. Specifically, the mechanical properties of the 3D printed lining with in-situ laying of integrated steel bars can be explored through compression, flexure, and tension tests; the bonding performance between the 3D printed lining and the tunnel ring can be explored through pull-out tests; the microscopic morphology of the 3D printed lining surface can be explored through SEM experiments; the defects between the 3D printed lining and the in-situ laid steel bars can be explored through X-rays, gamma rays, or beta rays; and cracks and holes on the surface of the 3D printed lining can be detected through penetration tests.

[0043] The present invention can simulate actual working conditions on a smaller scale, thereby greatly reducing the research cost and research cycle of 3D printed linings with in-situ fusion steel bars in tunnel engineering. The present invention can be used to verify the feasibility of the design of 3D printed linings with in-situ fusion steel bars. Based on the data of the ground test device, it provides a good basis for exploring process parameters for the application of 3D printed linings with in-situ fusion steel bars in actual tunnel engineering. The present invention can also be used to explore the application effects of new structures and new materials, test new structures and new technologies at a lower risk, and provide a basis for practical application.

[0044] The present invention is equipped with a flexible steel bar clamping head to directly arrange steel bars between 3D printed lining layers to enhance the mechanical properties of the lining, thereby solving the problem of incompatibility between the in-situ 3D printed lining method and the traditional steel bar reinforcement method. The present invention uses a steel bar in-situ laying module to replace the steel bar bending machine, steel bar bundling machine, mold production line and other equipment required by the traditional prefabricated steel bar cage, thereby reducing unnecessary cost losses while ensuring long-term stable support of the tunnel lining. The present invention uses a structured light camera to scan the tunnel section and the printed filaments to obtain morphological geometric information, and realize online control of the secondary lining printing parameters and steel bar laying parameters. The flexible steel bar clamping head used in the present invention can meet the needs of arranging steel bars of different diameters and shapes, and provides a good hardware foundation for integrating multiple steel bars in-situ laying to enhance the ground test of the mechanical properties of 3D printed linings. At the same time, the present invention provides excellent expansion space for the performance verification of the new composite 3D printing nozzle and the steel bar clamping head, and provides great help for efficient and safe lining operations in engineering practice.

[0045] The above-mentioned embodiments only express several implementation methods of the present invention, and the description is relatively specific and detailed, but it cannot be understood as limiting the scope of the present invention. For ordinary technicians in this field, several modifications and improvements can be made without departing from the concept of the present invention, which all belong to the protection scope of the present invention.

Claims

1. A 3D printed lining ground test device with in-situ laying of steel bars, characterized in that: The device includes a mixing and pumping module, a 3D printing lining module, a 3D printing lining mechanical arm, a steel bar in-situ laying module, a steel bar in-situ laying mechanical arm and a tunnel ring; The mixing and pumping module is used to mix and prepare fresh concrete materials, and pump the fresh concrete materials to the 3D printing lining module; The 3D printing lining module includes a nozzle installed at the end of the 3D printing lining mechanical arm, the 3D printing lining mechanical arm is used to drive the 3D printing lining module to move, and the 3D printing lining module is used to print fresh concrete materials in the tunnel ring through the nozzle; The steel bar in-situ laying module is installed at the end of the steel bar in-situ laying robotic arm, and the steel bar in-situ laying robotic arm is used to drive the steel bar in-situ laying module to move; the steel bar in-situ laying module includes a flexible steel bar clamping head and a structured light camera, the flexible steel bar clamping head is used to clamp and place steel bars, and the structured light camera is used to scan the surface morphology of the inner surface of the tunnel ring and the surface morphology of the printed lining part, so as to provide data support for the motion planning of the 3D printing lining robotic arm and the steel bar in-situ laying robotic arm.

2. The 3D printed lining ground test device for in-situ laying of fused steel bars according to claim 1 is characterized in that: The inner surface of the tunnel ring simulates the inner surface of a real tunnel to be printed with lining.

3. The 3D printed lining ground test device for in-situ laying of fused steel bars according to claim 1 is characterized in that: The device also includes a workbench for fixing the tunnel ring, and the 3D printing lining robot arm and the in-situ steel bar laying robot arm are arranged on both sides of the workbench along the axis of the tunnel ring. The workbench, the 3D printing lining robot arm and the in-situ steel bar laying robot arm are all fixed on the ground.

4. The 3D printed lining ground test device for in-situ laying of fused steel bars according to claim 1 is characterized in that: The mixing and pumping module includes a mixer, a fiber hose, a hose pump and a concrete delivery pump. The mixer is used to mix and prepare fresh concrete materials, including a mixing bin and a mixing structure in the mixing bin. The concrete delivery pump is used to store fresh concrete materials and pump the stored materials to the 3D printing lining module. There are two fiber hoses, and the inlet end of the hose pump is connected to the mixing bin through one of the fiber hoses, and the outlet end of the hose pump is connected to the concrete delivery pump through the other fiber hose.

5. The 3D printed lining ground test device for in-situ laying of fused steel bars according to claim 4 is characterized in that: The inlet and outlet ends of the hose pump are provided with crimping pipe joints.

6. The 3D printed lining ground test device for in-situ laying of fused steel bars according to claim 1 is characterized in that: The 3D printing lining module also includes a stepper motor, a motor support seat, a rigid coupling, a spiral extrusion rod, a hopper and a barrel scraper; the hopper is used to hold steel fiber concrete materials, the stepper motor is installed at one end of the hopper through the motor support seat, and the other end of the hopper gradually shrinks to form a hopper outlet, the hopper outlet is threadedly connected to the nozzle, and a hole is opened on the side of the hopper to form a feed port, and the feed port is connected to the stirring and pumping module through a pressure-resistant hose; the output shaft of the stepper motor is connected to the spiral extrusion rod through a rigid coupling, and the spiral extrusion rod is located in the hopper and is used to extrude the material in the hopper from the nozzle; the barrel scraper is welded on the spiral extrusion rod to scrape off the concrete accumulated on the inner wall of the hopper during the 3D printing process.

7. The 3D printed lining ground test device for in-situ laying of fused steel bars according to claim 1 is characterized in that: The steel bar in-situ laying module also includes an air intake device, an air pipe and an air pump. The air intake device is connected to the air pump through the air pipe. The air pump is used to adjust the internal air pressure of the air intake device, thereby controlling the clamping action of the flexible steel bar clamping head.

8. The 3D printed lining ground test device for in-situ laying of fused steel bars according to claim 1 is characterized in that: The ends of the 3D printing lining robot arm and the in-situ steel bar laying robot arm are both provided with flanges. The 3D printing lining module is threadedly connected to the 3D printing lining robot arm through the flange at the end of the 3D printing lining robot arm, and the steel bar in-situ laying module is threadedly connected to the in-situ steel bar laying robot arm through the flange at the end of the in-situ steel bar laying robot arm.

9. The 3D printed lining ground test device for in-situ laying of fused steel bars according to claim 1 is characterized in that: The 3D printing lining robot arm and the in-situ steel bar laying robot arm are both six-degree-of-freedom robot arms.

10. A test method for a 3D printed lining ground test device based on the in-situ laying of fused steel bars as claimed in claim 1, characterized in that: The method comprises: 1) The in-situ steel bar laying robot drives the structured light camera to scan along the inside of the tunnel ring to generate the inner surface morphology of the tunnel ring. Based on the inner surface morphology of the tunnel ring, the motion trajectory of the 3D printing lining robot and the in-situ steel bar laying robot to manufacture the first layer of the lining is planned; 2) The concrete raw materials are fed into the mixing and pumping module, and the mixing and pumping module mixes the concrete raw materials to produce fresh concrete materials; 3) The mixing and pumping module pumps the fresh concrete material to the 3D printing lining module, and the 3D printing lining module extrude the fresh concrete material from the nozzle onto the tunnel ring. The 3D printing lining robot arm drives the 3D printing lining module to move according to the plan to print a single layer of lining; 4) After the single-layer lining is printed, the in-situ steel bar laying robot arm drives the flexible steel bar clamping head to clamp the steel bars according to the plan, and arranges the clamped steel bars on the printed single-layer lining; 5) After completing the steel bar arrangement on a single layer of lining, the steel bar in-situ laying robot arm drives the structured light camera to scan the surface morphology of the currently printed lining part; based on the surface morphology of the printed lining part and the surface morphology of the tunnel ring, the motion trajectory of the 3D printing lining robot arm and the steel bar in-situ laying robot arm to manufacture the next layer of lining is planned; 6) Execute the above steps 3)-5) repeatedly until the printing of the required lining is completed; 7) Carry out performance tests on the tunnel rings with printed lining and evaluate the lining quality based on the performance test results.

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