Shield tunnel synchronous grouting model test device and method

Abstract

This invention provides a synchronous grouting model test device and method for shield tunnels, belonging to the field of shield tunnel construction technology. The synchronous grouting model test device for shield tunnels includes a working condition simulation base; a model box is set on the working condition simulation base; the interior of the model box is divided into a stratum simulation layer, a tail grouting cavity layer, and a segment simulation layer from top to bottom; a tail grouting simulation box is set in the tail grouting cavity layer; the tail grouting simulation box is provided with grouting holes for grouting; a grouting system has grouting pipelines; the grouting pipelines are connected to the grouting holes; the grouting system injects grout into the tail grouting simulation box through the grouting pipelines and grouting holes. The synchronous grouting model test device for shield tunnels provided by this invention collects grouting pressure and grouting flow data in real time during the test. The controller can quickly complete parameter comparison and calculation based on the collected real-time data. The system can automatically adjust the grouting output state to keep the grouting pressure and flow stable within a preset range.

Description

Technical Field

[0001] This invention belongs to the technical field of shield tunnel construction, and more specifically, it relates to a test device and method for synchronous grouting model in shield tunnels. Background Technology

[0002] Shield tunneling is currently the mainstream technology for tunnel construction. Simultaneous grouting, as a core procedure in shield tunneling, directly determines the effectiveness of ground settlement control and the long-term stability of the tunnel structure, making it a crucial link in ensuring construction safety and project quality. During simultaneous grouting, the flow and solidification characteristics of the grout under complex geological conditions and special spatial morphology constitute complex mechanical behavior involving multiple coupled fields. It is difficult to fully reveal its mechanism through field measurements; therefore, indoor model tests have become an important means of studying grouting patterns and optimizing grouting processes.

[0003] The existing experimental devices have the following drawbacks: key parameters such as grouting pressure, flow rate, and mix ratio are mostly preset manually, and dynamic and precise adjustment cannot be achieved based on monitoring feedback during the test, thus failing to truly reproduce the grouting response characteristics under complex working conditions. Summary of the Invention

[0004] The purpose of this invention is to provide a test device and method for synchronous grouting model in shield tunnels, which aims to solve the problem that existing test devices cannot be dynamically and accurately adjusted during the experiment and cannot truly reproduce the corresponding characteristics of grouting under complex working conditions.

[0005] To achieve the above objectives, the technical solution adopted by the present invention is as follows: Firstly, a test device for synchronous grouting model of a shield tunnel is provided, comprising: Working condition simulation base; The model box is set on the working condition simulation base; the interior of the model box is divided into the stratum simulation layer, the shield tail grouting cavity layer and the segment simulation layer from top to bottom. A tail shield simulation box is installed in the tail shield grouting cavity layer; the tail shield simulation box is provided with grouting holes for grouting. The grouting system includes grouting pipelines; the grouting pipelines are connected to the grouting holes; the grouting system injects grout into the tail shield simulation box through the grouting pipelines and the grouting holes; A pressure sensor is used to detect the pressure during grouting in the grouting system and output real-time pressure information; A flow sensor is used to detect the flow rate during grouting in the grouting system and output real-time flow information; The controller is communicatively connected to the pressure sensor, the flow sensor, and the grouting system; the controller is configured to: Receive the real-time pressure information and the real-time flow information; The flow rate and pressure of the grouting system are adjusted based on the real-time pressure information, the real-time flow rate information, the preset flow rate value, and the preset pressure value.

[0006] In one possible implementation, the grouting system includes a flow control valve and a pressure control valve; the controller is communicatively connected to both the flow control valve and the pressure control valve; adjusting the flow rate and pressure of the grouting system according to the real-time pressure information, the real-time flow information, a preset flow rate value, and a preset pressure value includes: Calculate the difference between the real-time pressure information and the preset pressure value, and the difference between the real-time flow information and the preset flow value; The opening of the pressure control valve is adjusted according to the difference between the real-time pressure information and the preset pressure value, so as to adjust the grouting pressure of the grouting system and stabilize it at the preset pressure value. The opening of the flow control valve is adjusted according to the difference between the real-time flow information and the preset flow value, so as to adjust the grouting flow of the grouting system and stabilize it at the preset flow value.

[0007] In one possible implementation, the grouting system includes a first branch and a second branch. The first branch is equipped with a first electrically controlled proportional valve, and the second branch is equipped with a second electrically controlled proportional valve. Both the first and second electrically controlled proportional valves are communicatively connected to the controller. The first electrically controlled proportional valve is used for grouting the base grout or a quick-setting agent, and the second electrically controlled proportional valve is used for grouting the quick-setting agent or the base grout. Two flow sensors are provided, which are used to detect and output the flow information of the first branch and the second branch, respectively. The controller is configured to: Receive the first real-time traffic information and the second real-time traffic information; The flow rates of the first and second electrically controlled proportional valves are adjusted according to the preset ratio, the flow rate information of the first tributary, and the flow rate information of the second tributary.

[0008] In one possible implementation, adjusting the flow rates of the first and second electrically controlled proportional valves according to a preset ratio, the first tributary flow rate information, and the second tributary flow rate information includes: Calculate real-time flow information based on the first tributary flow information and the second tributary flow information; The flow rates of the first and second electrically controlled proportional valves are calculated based on the preset ratio and the real-time flow information.

[0009] In one possible implementation, the working condition simulation base includes: Support frame; A rotating frame is rotatably connected to the support frame; the model box is fixedly connected to the rotating frame; the rotating frame is used to adjust the angle between the model box and the horizontal plane. The positioning rod has one end mounted on the support frame and the other end abutting against the side of the model box.

[0010] In one possible implementation, the model box includes: The frame is fixedly connected to the rotating frame; A side panel is fixedly connected to the frame; the inside of the side panel is transparent, and the end of the positioning rod abuts against the side panel.

[0011] In one possible implementation, the support frame is provided with mounting holes, one end of the positioning rod is inserted into the mounting holes, and the other end abuts against the side plate.

[0012] One possible implementation also includes: The rotating roller is mounted on the support frame or on the ground. A rope is fixedly connected at one end to the rotating roller and at the other end to the tail shield simulation box; the middle part of the rope is wound around the rotating roller. The motor has its power output shaft fixedly connected to the rotating roller; the motor is used to drive the rotating roller to rotate.

[0013] One possible implementation also includes a monitoring system for collecting data on grout diffusion patterns, soil stress, displacement, and segment strain during the grouting process.

[0014] Secondly, a method for testing a multi-directional shield tunnel synchronous grouting model is provided, applied to the shield tunnel synchronous grouting model test device as described in the first aspect, comprising: The model box is adjusted and fixed to the target tilt angle using the working condition simulation base; The soil was filled in layers in the geological simulation layer and sensors were installed, and then compacted to a predetermined density. Install the shield tail simulation box in the starting position and connect the grouting pipeline; Preset grouting parameters; The shield tail simulation box is moved at a constant speed to form a building gap; when the set gap is reached, grouting is started, and the grouting parameters can be dynamically adjusted according to real-time data. Simultaneously collect various data throughout the entire grouting process and during the grout hardening process; After the test, the distribution of grout veins was observed by excavating the soil, and samples were taken to test the physical and mechanical properties of the hardened grout.

[0015] The beneficial effects of the shield tunnel synchronous grouting model test device provided by this invention are as follows: Compared with the prior art, the shield tunnel synchronous grouting model test device of this invention collects grouting pressure and grouting flow data in real time during the test. The controller can quickly complete parameter comparison and calculation based on the collected real-time data. The system can automatically adjust the grouting output state to keep the grouting pressure and flow stable within the preset range.

[0016] The dynamic adjustment mechanism can accurately reproduce the complex and ever-changing grouting conditions during tunnel boring machine (TBM) construction. The testing process requires no manual intervention, effectively reducing errors caused by human operation. Data acquisition and parameter control are carried out simultaneously, significantly improving the authenticity and reliability of the test results.

[0017] The model box can be flexibly adjusted and its tilt angle fixed, simulating tunnel construction conditions with different slopes. The layered structure design clearly reproduces the real spatial relationship between the strata, grouting cavities, and tunnel segments. The entire device fully replicates the mechanical behavior and grout diffusion laws of synchronous grouting, providing accurate support for optimizing shield tunnel construction technology. Attached Figure Description

[0018] To more clearly illustrate the technical solutions in the embodiments of the present invention, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0019] Figure 1 This is a schematic diagram of the structure of the shield tunnel synchronous grouting model test device provided in an embodiment of the present invention; Figure 2 This is a schematic diagram of the structure of the working condition simulation base and model box provided in an embodiment of the present invention; Figure 3 A schematic diagram of the main steps of the multi-directional shield tunnel synchronous grouting model test method provided in the embodiments of the present invention.

[0020] Explanation of reference numerals in the attached figures: 1. Working condition simulation base; 11. Support frame; 12. Rotating frame; 13. Positioning rod; 2. Model box; 21. Frame; 22. Side plate; 3. Shield tail simulation box; 4. Rotating roller; 5. Rope; 6. Motor. Detailed Implementation

[0021] To make the technical problems to be solved, the technical solutions, and the beneficial effects of the present invention clearer, the present invention will be further described in detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative of the present invention and are not intended to limit the present invention.

[0022] Based on the embodiments in this application, all other embodiments obtained by those skilled in the art without inventive effort are within the scope of protection of this application.

[0023] It should be further noted that the accompanying drawings and embodiments of the present invention mainly describe the concept of the present invention. Based on this concept, some specific forms and arrangements of connection relationships, positional relationships, power mechanisms, power supply systems, hydraulic systems and control systems may not be fully described. However, under the premise that those skilled in the art understand the concept of the present invention, they can implement the above-mentioned specific forms and arrangements in a well-known manner.

[0024] When a component is referred to as being "fixed to" or "set on" another component, it can be directly on or indirectly on that other component. When a component is referred to as being "connected to" another component, it can be directly connected to or indirectly connected to that other component.

[0025] In the description of this invention, "a plurality of" means two or more, and "several" means one or more, unless otherwise explicitly specified.

[0026] The directional terms "inner" and "outer" refer to the inner and outer contours of each component itself. The terms "length," "width," "upper," "lower," "front," "rear," "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 the present 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 the present invention.

[0027] For ease of description, spatial relative terms such as "above," "on top of," "on the upper surface of," and "above" are used here to describe the spatial positional relationship between a device or feature and other devices or features, as shown in the figure. It should be understood that spatial relative terms are intended to... The invention includes different orientations of the device in use or operation, in addition to those described in the figures. For example, if a device in the figures is inverted, a device described as "above" or "on top of" other devices or structures will be positioned as "below" or "under" other devices or structures. Thus, the exemplary term "above" can include both "above" and "below". The device may also be positioned in other different ways, and the spatial relative descriptions used herein are interpreted accordingly. The terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of indicated technical features. Thus, a feature defined as "first" or "second" may explicitly or implicitly include one or more of that feature. In the description of the invention, "a plurality of" means two or more, and "a number" means one or more, unless otherwise explicitly specified.

[0028] Reference Figures 1 to 3 The present invention will now describe the shield tunnel synchronous grouting model test device and method provided by the present invention.

[0029] In the first aspect, a test device for synchronous grouting model of shield tunnel is provided, including: working condition simulation base, model box, shield tail simulation box, grouting system, pressure sensor, flow sensor and controller.

[0030] The model box is mounted on the working condition simulation base. The interior of the model box, from top to bottom, is divided into a geological formation simulation layer, a tail grouting cavity layer, and a segment simulation layer. The tail grouting simulation box is located within the tail grouting cavity layer and is equipped with grouting holes for grouting. The grouting system has grouting pipelines connected to the grouting holes; the grouting system injects grout into the tail grouting simulation box through the grouting pipelines and grouting holes. A pressure sensor detects the pressure during grouting and outputs real-time pressure information. A flow sensor detects the flow rate during grouting and outputs real-time flow information. The controller is communicatively connected to the pressure sensor, flow sensor, and grouting system; the controller is configured as follows: Receive real-time pressure and traffic information; Adjust the flow and pressure of the grouting system based on real-time pressure information, real-time flow information, preset flow value, and preset pressure value.

[0031] The shield tunnel synchronous grouting model test device uses a working condition simulation base to adjust and fix the model box at its angle, ensuring it remains stable in the set test posture. Inside the model box, from top to bottom, there are three layers: a ground simulation layer, a tail grouting cavity layer, and a segment simulation layer, clearly reproducing the spatial structure of shield tunnel grouting. The tail simulation box is placed inside the tail grouting cavity layer, and the grouting system is stably connected to the grouting holes via grouting pipes. Pressure sensors continuously collect pressure signals during the grouting process and transmit them outwards in real time. Flow sensors synchronously detect the grouting flow rate and output corresponding flow data. The controller receives pressure and flow signals in real time and compares the real-time values ​​with preset parameters. Based on the comparison results, the controller automatically adjusts the output state of the grouting system to maintain stable grouting pressure and flow rate.

[0032] The entire system enables dynamic and precise parameter control throughout the entire testing process, effectively improving the controllability of grouting operations. The combination of real-time monitoring and automatic adjustment allows for the realistic reproduction of grouting response characteristics under complex working conditions. The layered model box structure can completely replicate the interaction between the strata, grouting cavity, and tunnel segments. The angle-adjustable base can adapt to various tunnel dip angles, expanding the scope of testing applications. The automated control mode reduces errors caused by manual intervention, improving the accuracy and reliability of test data. Stable and precise grouting control clearly reflects the diffusion and hardening patterns of the grout, providing reliable support for optimizing shield tunnel construction technology.

[0033] In one possible implementation, the grouting system includes a flow control valve and a pressure control valve; a controller is communicatively connected to both the flow control valve and the pressure control valve; the flow rate and pressure of the grouting system are adjusted based on real-time pressure information, real-time flow information, preset flow rate values, and preset pressure values, including: Calculate the difference between real-time pressure information and preset pressure value, and the difference between real-time flow information and preset flow value.

[0034] The difference between the real-time pressure information and the preset pressure value is calculated using the following formula:

[0035] in, The difference between real-time pressure information and preset pressure value; Preset pressure value; This provides real-time pressure information.

[0036] The difference between real-time traffic information and preset traffic value is calculated using the following formula.

[0037] in, The difference between real-time traffic information and preset traffic value; Preset flow rate value; This provides real-time traffic information.

[0038] The opening of the pressure control valve is adjusted according to the difference between the real-time pressure information and the preset pressure value, so as to adjust the grouting pressure of the grouting system and stabilize it at the preset pressure value.

[0039] Adjust the opening degree of the pressure control valve using the following formula:

[0040] in, To adjust the opening degree of the pressure control valve; The difference between real-time pressure information and preset pressure value; This is the initial opening. The integral coefficient; These are the differential coefficients; For time.

[0041] The opening of the flow control valve is adjusted according to the difference between the real-time flow information and the preset flow value, so as to adjust the grouting flow of the grouting system and stabilize it at the preset flow value.

[0042] Adjust the opening degree of the flow control valve using the following formula:

[0043] in, To adjust the opening degree of the flow control valve; The difference between real-time traffic information and preset traffic value; This is the initial opening. This is the proportionality coefficient; is the integral coefficient.

[0044] By calculating the difference between the grouting pressure and the preset pressure in real time, the opening of the pressure control valve can be quickly adjusted. This method ensures that the grouting pressure is stably maintained at the set value, avoiding the impact of pressure fluctuations on test results. By calculating the difference between the grouting flow rate and the preset flow rate in real time, the opening of the flow control valve can be precisely adjusted. This method ensures that the grouting flow rate remains stable, guaranteeing that the grout injection volume meets test requirements. Independent control of pressure and flow rate does not interfere with each other, improving the control accuracy of the grouting process. Fully automated adjustment requires no manual intervention, effectively reducing test errors caused by human operation. Stable and controllable grouting conditions can realistically reproduce on-site construction conditions, improving the reliability and repeatability of test data. Clear and controllable parameter changes can accurately reflect the grout diffusion and stratum response patterns, providing precise support for research on synchronous grouting in shield tunnels.

[0045] In one possible implementation, the grouting system includes a first branch and a second branch. The first branch is equipped with a first electrically controlled proportional valve, and the second branch is equipped with a second electrically controlled proportional valve. Both the first and second electrically controlled proportional valves are communicatively connected to a controller. The first electrically controlled proportional valve is used for grouting the base grout or a quick-setting agent, and the second electrically controlled proportional valve is used for grouting the quick-setting agent or the base grout. Two flow sensors are provided, which are used to detect and output the flow information of the first branch and the second branch, respectively. The controller is configured as follows: Receive first real-time traffic information and second real-time traffic information.

[0046] Adjust the flow rates of the first and second electrically controlled proportional valves according to the preset ratio, the flow rate information of the first tributary, and the flow rate information of the second tributary.

[0047] In one possible implementation, adjusting the flow rates of the first and second electrically controlled proportional valves based on a preset ratio, the flow rate information of the first branch, and the flow rate information of the second branch includes: Real-time flow information is calculated based on the flow information of the first tributary and the flow information of the second tributary.

[0048] Real-time traffic information is calculated using the following formula:

[0049] in, Real-time traffic information; This refers to the flow information of the first tributary. This is the flow information for the second tributary.

[0050] The flow rates of the first and second electronically controlled proportional valves are calculated based on the preset ratio and real-time flow information.

[0051] The flow rates of the first and second electro-hydraulic proportional valves are calculated using the following formula:

[0052]

[0053] in, The flow rate of the first electrically controlled proportional valve; The flow rate of the second electrically controlled proportional valve; It is a time function; The maximum flow rate of the first electrically controlled proportional valve; This represents the maximum flow rate of the second electrically controlled proportional valve.

[0054] Employing two independent grouting branches and corresponding electrically controlled proportional valves, the system can separately deliver the base grout and accelerator, achieving precise proportioning of grouting materials. Each branch is equipped with an independent flow sensor, enabling real-time acquisition and synchronous uploading of their respective flow data. The controller automatically calculates and adjusts the opening of the two electrically controlled proportional valves based on the preset proportions and real-time flow data. Full closed-loop control ensures a stable grout ratio, preventing deviations from affecting test results. The independent branch design enhances the flexibility of material delivery, accommodating various grouting material combinations. Automated proportioning adjustment eliminates the need for manual intervention, effectively reducing experimental errors. Stable and reliable proportioning control accurately replicates the mixing state of grouting materials on-site, improving the accuracy and repeatability of test data. Precise and controllable material proportioning clearly reflects grout performance and ground response patterns, providing reliable support for research on the synchronous grouting mechanism of shield tunnels.

[0055] In one possible implementation, the working condition simulation base includes: a support frame, a rotating frame, and a positioning rod. The rotating frame is rotatably connected to the support frame; the model box is fixedly connected to the rotating frame; the rotating frame is used to adjust the angle between the model box and the horizontal plane. One end of the positioning rod is set on the support frame, and the other end abuts against the side of the model box.

[0056] In a preferred embodiment, the working condition simulation base is configured as a cube frame, with two intersecting support rods on each of two opposite sides of the cube frame, the two support rods being arranged along the diagonal of their respective sides. A positioning hole is provided at the intersection of the two support rods. The rotating frame is horizontally positioned, with rotating shafts at both ends, the shafts being rotatably mounted in the positioning holes.

[0057] In one possible implementation, the model box includes a frame and side panels.

[0058] The frame is fixedly connected to the rotating frame. The side panels are fixedly connected to the frame; the inside of the side panels is transparent, and the ends of the positioning rods abut against the side panels.

[0059] In one possible implementation, the support frame is provided with mounting holes, one end of the positioning rod is inserted into the mounting holes, and the other end abuts against the side plate.

[0060] In a preferred embodiment, the side panel is made of a flexible and transparent acrylic sheet. The length of the positioning rod is slightly longer than the distance between the side panel and the support frame. When adjusting the angle of the model box, one end of the positioning rod is inserted into the mounting hole, and the other end abuts against the side panel, causing a slight deformation of the side panel. The friction between the positioning rod and the side panel is used to fix the angle of the model box.

[0061] One possible implementation also includes a roller, a rope, and a motor.

[0062] The rotating roller is mounted on a support frame or on the ground. One end of a rope is fixedly connected to the rotating roller, and the other end is fixedly connected to the tail shield simulation box; the middle part of the rope is wound around the rotating roller. The motor's power output shaft is fixedly connected to the rotating roller; the motor is used to drive the rotating roller to rotate.

[0063] When demolding the shield tail simulation box, the motor drives the rotating roller to rotate. As the roller rotates, it tightens the rope, pulling the shield tail simulation box out.

[0064] One possible implementation also includes a monitoring system for collecting data on grout diffusion patterns, soil stress, displacement, and segment strain during the grouting process.

[0065] The monitoring system includes a high-definition camera, an earth pressure sensor, a displacement sensor, and strain gauges. The high-definition camera is arranged on the outside of the side wall of the model box to record the diffusion pattern of the slurry. The earth pressure sensor is embedded in a grid pattern on the outside of the simulated pipe segment layer and inside the soil. The displacement sensor monitors the radial / axial displacement of the pipe segment. The strain gauges are attached to the surface of the pipe segment.

[0066] Secondly, a method for testing a multi-directional shield tunnel synchronous grouting model is provided, applied to the shield tunnel synchronous grouting model test device as described in the first aspect, comprising: S100. Adjust and fix the model box to the target tilt angle using the working condition simulation base.

[0067] S200. Soil is filled in layers in the geological simulation layer and sensors are installed, and then compacted to the predetermined density.

[0068] S300. Install the tail shield simulation box in the starting position and connect the grouting pipeline.

[0069] S400. Preset grouting parameters.

[0070] S500. The shield tail simulation box is moved at a constant speed to form a building gap; when the set gap is reached, grouting is started, and the grouting parameters can be dynamically adjusted according to real-time data.

[0071] S600. Synchronously collects various data during the entire grouting process and the grout hardening process.

[0072] S700. After the test, the soil was excavated to observe the distribution of grout veins, and samples were taken to test the physical and mechanical properties of the hardened grout.

[0073] The beneficial effects of the shield tunnel synchronous grouting model test device provided by this invention are as follows: Compared with the prior art, the shield tunnel synchronous grouting model test device of this invention collects grouting pressure and grouting flow data in real time during the test. The controller can quickly complete parameter comparison and calculation based on the collected real-time data. The system can automatically adjust the grouting output state to keep the grouting pressure and flow stable within the preset range.

[0074] The dynamic adjustment mechanism can accurately reproduce the complex and ever-changing grouting conditions during tunnel boring machine (TBM) construction. The testing process requires no manual intervention, effectively reducing errors caused by human operation. Data acquisition and parameter control are carried out simultaneously, significantly improving the authenticity and reliability of the test results.

[0075] The model box can be flexibly adjusted and its tilt angle fixed, simulating tunnel construction conditions with different slopes. The layered structure design clearly reproduces the real spatial relationship between the strata, grouting cavities, and tunnel segments. The entire device fully replicates the mechanical behavior and grout diffusion laws of synchronous grouting, providing accurate support for optimizing shield tunnel construction technology.

[0076] 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, and improvements made within the spirit and principles of the present invention should be included within the protection scope of the present invention.

[0077] It should be noted that the terminology used herein is for the purpose of describing particular embodiments only and is not intended to limit the exemplary embodiments according to this application. As used herein, the singular form is intended to include the plural form as well, unless the context clearly indicates otherwise. Furthermore, it should be understood that when the terms "comprising" and / or "including" are used in this specification, they indicate the presence of features, steps, operations, devices, components, and / or combinations thereof.

[0078] Unless otherwise specifically stated, the relative arrangement, numerical expressions, and values ​​of the components and steps described in these embodiments do not limit the scope of this application. It should also be understood that, for ease of description, the dimensions of the various parts shown in the drawings are not drawn to actual scale. Techniques, methods, and devices known to those skilled in the art may not be discussed in detail, but where appropriate, such techniques, methods, and devices should be considered part of the specification. In all examples shown and discussed herein, any specific values ​​should be interpreted as merely exemplary and not as limitations. Therefore, other examples of exemplary embodiments may have different values. It should be noted that similar reference numerals and letters in the following drawings denote similar items; therefore, once an item is defined in one drawing, it need not be further discussed in subsequent drawings.

Claims

1. A test device for synchronous grouting model in shield tunnels, characterized in that, include: Working condition simulation base; The model box is set on the working condition simulation base; the interior of the model box is divided into the stratum simulation layer, the shield tail grouting cavity layer and the segment simulation layer from top to bottom. A tail shield simulation box is installed in the tail shield grouting cavity layer; the tail shield simulation box is provided with grouting holes for grouting. The grouting system includes grouting pipelines; the grouting pipelines are connected to the grouting holes. The grouting system injects grout into the tail shield simulation box through the grouting pipeline and the grouting hole; A pressure sensor is used to detect the pressure during grouting in the grouting system and output real-time pressure information; A flow sensor is used to detect the flow rate during grouting in the grouting system and output real-time flow information; The controller is communicatively connected to the pressure sensor, the flow sensor, and the grouting system; the controller is configured to: Receive the real-time pressure information and the real-time flow information; The flow rate and pressure of the grouting system are adjusted based on the real-time pressure information, the real-time flow rate information, the preset flow rate value, and the preset pressure value.

2. The shield tunnel synchronous grouting model test device as described in claim 1, characterized in that, The grouting system includes a flow control valve and a pressure control valve; the controller is communicatively connected to both the flow control valve and the pressure control valve; adjusting the flow and pressure of the grouting system according to the real-time pressure information, the real-time flow information, a preset flow value, and a preset pressure value includes: Calculate the difference between the real-time pressure information and the preset pressure value, and the difference between the real-time flow information and the preset flow value; The opening of the pressure control valve is adjusted according to the difference between the real-time pressure information and the preset pressure value, so as to adjust the grouting pressure of the grouting system and stabilize it at the preset pressure value. The opening of the flow control valve is adjusted according to the difference between the real-time flow information and the preset flow value, so as to adjust the grouting flow of the grouting system and stabilize it at the preset flow value.

3. The shield tunnel synchronous grouting model test device as described in claim 1, characterized in that, The grouting system includes a first branch and a second branch. The first branch is equipped with a first electrically controlled proportional valve, and the second branch is equipped with a second electrically controlled proportional valve. Both the first and second electrically controlled proportional valves are communicatively connected to the controller. The first electrically controlled proportional valve is used for grouting the base grout or the quick-setting agent, and the second electrically controlled proportional valve is used for grouting the quick-setting agent or the base grout. Two flow sensors are provided, which are used to detect and output the flow information of the first branch and the second branch, respectively. The controller is configured to: Receive the first real-time traffic information and the second real-time traffic information; The flow rates of the first and second electrically controlled proportional valves are adjusted according to the preset ratio, the flow rate information of the first tributary, and the flow rate information of the second tributary.

4. The shield tunnel synchronous grouting model test device as described in claim 3, characterized in that, Adjusting the flow rates of the first and second electrically controlled proportional valves according to a preset ratio, the flow rate information of the first tributary, and the flow rate information of the second tributary includes: Calculate real-time flow information based on the first tributary flow information and the second tributary flow information; The flow rates of the first and second electrically controlled proportional valves are calculated based on the preset ratio and the real-time flow information.

5. The shield tunnel synchronous grouting model test device as described in claim 1, characterized in that, The working condition simulation base includes: Support frame; A rotating frame is rotatably connected to the support frame; the model box is fixedly connected to the rotating frame; the rotating frame is used to adjust the angle between the model box and the horizontal plane. The positioning rod has one end mounted on the support frame and the other end abutting against the side of the model box.

6. The shield tunnel synchronous grouting model test device as described in claim 5, characterized in that, The model box includes: The frame is fixedly connected to the rotating frame; A side panel is fixedly connected to the frame; the inside of the side panel is transparent, and the end of the positioning rod abuts against the side panel.

7. The shield tunnel synchronous grouting model test device as described in claim 6, characterized in that, The support frame is provided with mounting holes, one end of the positioning rod is inserted into the mounting holes, and the other end abuts against the side plate.

8. The shield tunnel synchronous grouting model test device as described in claim 6, characterized in that, Also includes: The rotating roller is mounted on the support frame or on the ground. One end of the rope is fixedly connected to the rotating roller, and the other end is fixedly connected to the tail shield simulation box; The middle portion of the rope is wound around the roller; The motor has its power output shaft fixedly connected to the rotating roller; the motor is used to drive the rotating roller to rotate.

9. The shield tunnel synchronous grouting model test device as described in claim 1, characterized in that, It also includes a monitoring system for collecting data on grout diffusion patterns, soil stress, displacement, and segment strain during the grouting process.

10. A method for simultaneous grouting model testing of multi-directional shield tunnels, applied to the simultaneous grouting model testing device for shield tunnels as described in any one of claims 1-9, characterized in that, include: The model box is adjusted and fixed to the target tilt angle using the working condition simulation base; The soil was filled in layers in the geological simulation layer and sensors were installed, and then compacted to a predetermined density. Install the shield tail simulation box in the starting position and connect the grouting pipeline; Preset grouting parameters; The shield tail simulation box is moved at a constant speed to form a building gap; when the set gap is reached, grouting is started, and the grouting parameters can be dynamically adjusted according to real-time data. Simultaneously collect various data throughout the entire grouting process and during the grout hardening process; After the test, the distribution of grout veins was observed by excavating the soil, and samples were taken to test the physical and mechanical properties of the hardened grout.

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