Dual-purpose simulation test device and method for slurry shield simultaneous grouting and post-wall grouting

Abstract

The present application relates to the technical field of tunnel engineering, and particularly relates to a mud-water shield synchronous grouting and back-wall grouting dual-purpose simulation test device and a synchronous grouting and back-wall grouting test method. The device comprises a test box for simulating a shield environment, a simulation lining and a simulation shield shell are stacked in the test box, a compacted test soil layer simulating a soil body is arranged above the simulation shield shell, a traction system is arranged for pulling the simulation shield shell to slide on the simulation lining and simulate a shield tail gap at the tail of the simulation shield shell, a grouting system is arranged for grouting the simulated shield tail gap in the test box, and a measurement system is arranged for obtaining parameters related to synchronous grouting and / or back-wall grouting of a simulation mud-water shield. Compared with the prior art device, the device can simulate synchronous grouting and back-wall grouting tests of a shield under different tunneling speeds, grouting flow rates and ground loads, and can guide the regulation of parameters related to back-wall grouting of a shield.

Description

TECHNICAL FIELD

[0001] The present application belongs to the technical field of tunnel engineering, and relates to the field of civil engineering test and test technology research, and particularly relates to a mud-water shield synchronous grouting and back-wall grouting dual-purpose simulation test device, a synchronous grouting test method, a synchronous grouting and back-wall grouting test method and a back-wall grouting test method. BACKGROUND

[0002] The test method is a very important research means in the field of underground tunnel engineering, and at present, some enterprises, scientific research institutions and colleges and universities have established corresponding simulation experimental platforms to carry out shield tail synchronous grouting simulation experiments.

[0003] There is a certain difference between the outer diameter of the shield shell of the shield tunneling machine and the outer diameter of the segment, and when the shield machine advances in the tunneling direction, a gap is left between the soil and the segment; in order to effectively control the deformation of the surrounding soil and the ground settlement, and at the same time to protect the segment and transfer the load, it is necessary to fill the gap by grouting, and the grout is filled in the gap according to the predetermined pressure and grouting amount along with the advancement of the shield body; the segment also has grouting holes, and the surrounding rock of the tunnel is reinforced by segment grouting to improve the bearing capacity of the surrounding rock.

[0004] There is no experimental device for simulating synchronous grouting and segment back-wall grouting in the prior art, and for the related patents of shield back-wall grouting devices, for example, the invention patent with the application number 201310143410.7, "synchronous grouting simulation test platform for shield tunneling machine without working well", the device described in the patent comprises a large-scale sinking type comprehensive test table, a simulation segment, a simulation shield tail, a connecting flange, a cross beam, a circular portal, a hydraulic cylinder, a grouting pump, a soil pressure cell and a ground displacement meter, and the device can simulate the whole process of synchronous grouting when the shield machine advances under different working conditions.

[0005] The above-mentioned existing grouting simulation device has the following disadvantages:

[0006] 1. The existing device is mostly a similar model test device, and a large set of similar constants are required to obtain a test environment close to engineering practice, and the model size is required to be high, and the space and manufacturing cost of the model are greatly increased; reducing the geometric similarity constant often leads to the inability to use actual stratum materials and grouting slurry, and the shield tail gap, grouting pressure and flow are reduced, which is different from the actual situation; therefore, the existing experimental device cannot balance the similarity simulation effect, cost and space size;

[0007] 2. There is currently a lack of grouting simulation experimental device considering both synchronous grouting and back-wall grouting. SUMMARY

[0008] The present application is based on the problems in the prior art, and provides a mud-water shield synchronous grouting and back-wall grouting dual-purpose simulation test device and test method, which can simulate the mud-water shield synchronous grouting and back-wall grouting modes under different tunneling speeds, different grouting flow rates and different ground loads, can measure and record the soil pressure, pore water pressure and grouting flow rate data in real time during the experiment, and can obtain the relationship between the tunneling speed, grouting pressure, soil pressure and pore water pressure through further analysis. After the grouting body is taken out after the grouting body coagulates, the expansion of the grouting body in the soil body can be observed, and finally the parameter regulation and control related to the back-wall grouting of the shield can be guided.

[0009] The technical scheme of the present application is as follows: a mud-water shield synchronous grouting and back-wall grouting dual-purpose simulation test device, comprising:

[0010] A test box for simulating a shield environment, wherein a simulated lining and a simulated shield shell are stacked in the test box, and a compacted test soil layer simulating a soil body is arranged above the simulated shield shell;

[0011] A traction system for pulling the simulated shield shell to slide on the simulated lining and simulate a shield tail gap at the tail of the simulated shield shell;

[0012] A grouting system for grouting the simulated shield tail gap in the test box;

[0013] and

[0014] A measurement system for obtaining parameters related to the synchronous grouting and / or back-wall grouting of the simulated mud-water shield.

[0015] On the basis of the above scheme, the simulated shield shell is arranged at the upper part of the simulated lining, the simulated shield shell is provided with a synchronous grouting hole for grouting the shield tail gap, and the simulated lining is provided with a back-wall grouting hole penetrating up and down for back-wall grouting.

[0016] On the basis of the above scheme, a plurality of soil pressure sensors and a plurality of pore water pressure sensors are arranged in the test soil layer, and a load for providing simulated pressure is provided above the test soil layer during the test.

[0017] On the basis of the above scheme, the traction system comprises a servo electric cylinder arranged on the outer wall of the box body of the test box and used for pulling the simulated shield shell to simulate the shield tail gap at the tail of the simulated shield shell.

[0018] On the basis of the above scheme, the traction system further comprises a counterforce rod fixed between the box body and the servo electric cylinder.

[0019] A traction plate arranged at the distal end of the telescopic rod of the servo electric cylinder;

[0020] and

[0021] Several traction rods are fixed between the traction plate and the simulated shield shell.

[0022] Based on the above solution, the grouting system includes a grouting tank for holding slurry,

[0023] Air pump for increasing the pressure in the grouting tank,

[0024] A synchronous grouting pipeline is arranged on the grouting tank for transporting the slurry in the grouting tank to the shield tail gap for synchronous grouting, and a behind-the-wall grouting pipeline is used for behind-the-wall grouting.

[0025] On the basis of the above solution, the measurement system further includes a weighing plate arranged at the bottom of the grouting tank for measuring the weight change of the grouting tank and a recorder for collecting data information.

[0026] The synchronous grouting test method of the slurry shield, using the simulation test device, specifically includes the following steps:

[0027] (1) Place the simulated shield on the upper part of the simulated lining in the test box and seal the grouting holes behind the simulated lining;

[0028] (2) Connect the simulated shield to the traction system;

[0029] (3) A test soil layer is formed above the simulated shield by filling and compacting the soil in layers, and soil pressure sensors and pore water pressure sensors are buried during the filling process;

[0030] (4) Install the grouting tank on the weighing plate and inject slurry, and install the air pump;

[0031] (5) Connect the soil pressure sensor, pore water pressure sensor, weighing plate and recorder;

[0032] (6) According to the test purpose, the extension and retraction speed of the servo electric cylinder and the grouting pressure are set, and the synchronous grouting pipeline is opened so that the simulated shield shell is pulled out of the box at the set speed while grouting is injected into the shield tail gap through the synchronous grouting pipeline;

[0033] (7) After simulating the shield to be pulled for a certain distance, the servo electric cylinder and the synchronous grouting pipeline are closed at the same time, and the pore water pressure, soil pressure data and grouting tank weight change data are copied from the recorder. After the grouting slurry solidifies, the grouting body is taken out of the test box to observe the diffusion situation.

[0034] The slurry shield synchronous grouting and back-wall grouting test method uses the simulation test device and performs the back-wall grouting test after the synchronous grouting slurry solidifies. The synchronous grouting method uses the above method and specifically includes the following steps:

[0035] (1) opening the back grouting hole of the simulated lining wall, using a drilling machine to drill upward from the bottom of the test box, through the back grouting hole of the simulated lining wall and the synchronous grouting body, and into the test soil layer;

[0036] (2) installing a back grouting structure in the hole, specifically, inserting a grouting rod into the test soil layer and connecting a grouting head with the back grouting pipeline;

[0037] (3) opening the back grouting pipeline to start the test, and closing the back grouting pipeline after the test is completed;

[0038] (4) copying the pore water pressure data, soil pressure data and weight change data of the grouting tank through the recorder, and taking out the grouting body from the test box to observe the diffusion after the slurry is coagulated.

[0039] The mud water shield back grouting test method uses the simulated test device, and specifically includes the following steps:

[0040] (1) setting the simulated shield in the upper part of the simulated lining in the box body of the test box;

[0041] (2) connecting the simulated shield with the traction system;

[0042] (3) forming a test soil layer above the simulated shield by using the layered filling and compaction method, and burying the soil pressure sensor and the pore water pressure sensor during the filling;

[0043] (4) installing the grouting tank on the weighing plate and injecting mud, and installing the air pump;

[0044] (5) connecting the soil pressure sensor, the pore water pressure sensor, the weighing plate and the recorder;

[0045] (6) using the servo electric cylinder to pull the simulated shield towards the direction of the servo electric cylinder to expose the back grouting hole of the simulated lining wall;

[0046] (7) drilling upward from the back grouting hole of the simulated lining wall, through the shield tail gap and into the test soil layer;

[0047] (8) installing a grouting structure in the hole, specifically, inserting a grouting rod into the test soil layer and connecting a grouting head with the back grouting pipeline;

[0048] (9) opening the back grouting pipeline to start the test, and closing the back grouting pipeline after the test is completed;

[0049] (10) copying the pore water pressure data, soil pressure data and weight change data of the grouting tank through the recorder, and taking out the grouting body from the test box to observe the diffusion after the slurry is coagulated.

[0050] Compared with the device of the prior art, the device can simulate the synchronous grouting and the back wall grouting of the shield under different tunneling speeds, grouting flow rates and ground loads. The soil pressure, the seepage pressure and the grouting flow rate and speed data generated during the experiment can be measured and recorded in real time. After the grout solidifies, the grouting body can be taken out to observe the expansion of the grout in the soil. Finally, the device can guide the regulation of the parameters related to the back wall grouting of the shield. Especially, the device is provided with a grouting system including a synchronous grouting structure and a back wall grouting structure. The grouting system can be used in cooperation with other systems to meet the requirements of simulating the synchronous grouting and the back wall grouting of the shield under different tunneling speeds, grouting flow rates and ground loads, and effectively increase the simulation scenarios. The device and the test method can fully simulate the service state of the material of the slurry balance shield in the natural environment, and make the simulation state more in line with the actual situation. In addition, the systems and components included in the test device are easy to purchase and assemble, and the production cost is low. BRIEF DESCRIPTION OF DRAWINGS

[0051] Figure 1 FIG. 1 is a structural schematic diagram of a slurry shield synchronous grouting and back wall grouting dual-purpose simulation test device according to Embodiment 1 of the present application;

[0052] Figure 2 FIG. 2 is a structural schematic diagram of a test box (including a simulated lining and a simulated shield shell) according to Embodiment 1 of the present application;

[0053] Figure 3 FIG. 3 is a sectional structural schematic diagram of the simulated lining and the simulated shield shell according to Embodiment 1 of the present application;

[0054] Figure 4 FIG. 4 is a structural schematic diagram of the simulated lining according to Embodiment 1 of the present application;

[0055] Figure 5 FIG. 5 is a structural schematic diagram of the simulated shield shell according to Embodiment 1 of the present application;

[0056] Figure 6 FIG. 6 is a structural schematic diagram of a back wall grouting structure according to Embodiment 1 of the present application;

[0057] Figure 7 FIG. 7 is a structural schematic diagram of the installation state of a soil pressure sensor and a pore water pressure sensor according to Embodiment 1 of the present application;

[0058] Figure 8 FIG. 8 is a structural schematic diagram of the assembly of the test box and a traction system according to Embodiment 1 of the present application;

[0059] Figure 9 FIG. 9 is a structural schematic diagram of a grouting system according to Embodiment 1 of the present application;

[0060] Figure 10A structure schematic diagram of a slurry shield synchronous grouting and post-wall grouting dual-purpose simulation test device (simulating the state of the simulated shield shell being pulled out of the box by the shield shell traction system) in Embodiment 1 of the present application;

[0061] Figure 11 A structure schematic diagram of the installation of the measurement system in Embodiment 2 of the present application;

[0062] Figure 12 A structure schematic diagram of the synchronous grouting test (ungrouting state) in Step (6) of Embodiment 2 of the present application;

[0063] Figure 13 A structure schematic diagram of the synchronous grouting test (grouting state) in Step (6) of Embodiment 2 of the present application. DETAILED DESCRIPTION

[0064] The present application will be further described in detail below in conjunction with the accompanying drawings and embodiments, and it should be noted that the following embodiments are intended to facilitate the understanding of the present application and do not limit the present application in any way.

[0065] Embodiment 1

[0066] As shown in the drawings, Figures 1-3 the present application provides a slurry shield synchronous grouting and post-wall grouting dual-purpose simulation test device, which comprises:

[0067] a test box 1 for simulating a shield environment, wherein the test box 1 is provided with a simulated lining 120 and a simulated shield shell 130 stacked therein, and a simulated compacted test soil layer 140 of soil is arranged above the simulated shield shell 130;

[0068] a traction system 2 for pulling the simulated shield shell 130 to slide on the simulated lining 120 and simulate a shield tail gap 150 (the shield tail gap 150 refers to the space between the tail of the simulated shield shell 130 and the simulated lining 120 and the test soil layer 140) at the tail of the simulated shield shell 130;

[0069] a grouting system 3 for grouting the simulated shield tail gap 150 in the test box 1;

[0070] and

[0071] a measurement system 4 for obtaining parameters related to the synchronous grouting and / or post-wall grouting of the simulated slurry shield.

[0072] The shield environment refers to the fact that there is a certain difference between the outer diameter of the shield shell of the shield machine and the outer diameter of the segment, and when the shield machine is excavated, the shield body advances in the excavation direction, thereby leaving a gap between the soil and the segment.

[0073] The test soil layer 140 refers to the soil above the tunnel after the shield machine is excavated.

[0074] Specifically, the mud water shield synchronous grouting and / or back wall grouting related parameters include the tunneling speed in the test box 1, the earth pressure parameter, the pore water pressure parameter, the osmotic pressure, the grouting flow data and the rate data. The test device is applied to carry out mud water shield synchronous grouting and / or back wall grouting test to obtain the relationship of tunneling speed-grouting pressure-earth pressure-pore water pressure, and the grouting body is taken out after the slurry is coagulated to observe the expansion of the slurry in the soil body, so that the parameter regulation and control of the shield back wall grouting can be realized and a certain guidance can be provided.

[0075] The upper and lower openings of the box body 110 of the test box 1, and the bottom of the simulation lining 120 is the box body 110. Preferably, a reserved opening for the simulation shield 130 to slide out is arranged on one side of the box body 110. Preferably, as shown in Figure 3 The top of the simulation lining 120 is a curved surface (a cylindrical surface with a diameter of 6 m), the bottom is a flat surface, the top and bottom surfaces of the simulation shield 130 are curved surfaces (cylindrical surfaces with a diameter of 6 m), the simulation shield 130 is installed on the simulation lining 120 and can slide relative to the simulation lining 120, and the lower curved surface of the simulation shield 130 is arranged in close contact with the upper curved surface of the simulation lining 120.

[0076] As shown in Figures 4-5 As a specific embodiment, the simulation shield 130 is arranged on the upper part of the simulation lining 120; the simulation shield 130 is provided with a synchronous grouting hole 130-1 for grouting into the shield tail gap 150; the simulation lining 120 is provided with a back wall grouting hole 120-1 for back wall grouting.

[0077] The back wall grouting structure 160 can be installed in the back wall grouting hole 120-1, as shown in Figure 6 The back wall grouting structure 160 includes a grouting head 161 and a grouting rod 162, and the grouting rod 162 is connected with the grouting head 161 in use, and the number of grouting rods 162 can be selected according to the specific use scene; wherein the grouting head 161 is processed from a plug screw and a steel pipe, has a through hole with a diameter of 1 cm, and a steel pipe with a length of 1 cm, an inner diameter of 1 cm and a wall thickness of 0.1 cm is welded on the small cylindrical surface, and a steel pipe with a length of 1 cm, an inner diameter of 0.8 cm and a wall thickness of 0.1 cm is welded on the large cylindrical surface; as shown in Figure 6 The grouting rod 162 is a steel pipe with a total length of 6 cm, one end is an M10x1.5 external thread, and the other end is an M20x1.5 internal thread.

[0078] As a specific embodiment, as shown in Figure 7As shown, a plurality of earth pressure sensors 5 and a plurality of pore water pressure sensors 6 are arranged in the test soil layer 140, and a load providing simulated pressure is provided above the test soil layer 140 during the test.

[0079] As a specific embodiment, as shown in Figure 8 As shown, the traction system 2 includes a servo-cylinder 210 arranged on the outer wall of the box body 110 of the test box 1 and used to pull the simulation shield 130 to simulate the tail gap 150 at the tail of the simulation shield 130.

[0080] The traction system 2 further includes a counter-force rod 220 fixed between the box body 110 and the servo-cylinder 210.

[0081] A traction plate 240 arranged at the distal end of the telescopic rod 230 of the servo-cylinder 210 and a plurality of traction rods 250 fixed between the traction plate 240 and the simulation shield 130.

[0082] In use, in order to ensure that the servo-cylinder 210 is consistent with the height of the simulation shield 130, the servo-cylinder 210 is installed on the base, the telescopic rod 230 is connected to the traction plate 240, the traction plate 240 is connected to the four traction rods 220, the traction rods 220 are connected to the simulation shield 140, and the simulation shield 140 is pulled to slide on the simulation lining 120 by the servo-cylinder 210. Among them, the servo-cylinder 210 can adopt a conventional commercially available device, which does not belong to the innovation of the present application, and will not be described in detail here.

[0083] As a specific embodiment, as shown in Figures 9-10As shown, the grouting system 3 includes a grouting tank 310 for containing slurry, an air pump 320 for pressurizing the grouting tank 310, a synchronous grouting pipeline 330 provided on the grouting tank 310 for delivering slurry in the grouting tank 310 to the tail gap 150 for synchronous grouting, and a backwall grouting pipeline 340 for backwall grouting (one end of the backwall grouting hole 120-1 in the simulated lining 120 is connected to the backwall grouting structure 160 and the other end is connected to the backwall grouting pipeline 340). Specifically, the tank body of the grouting tank 310 is made of steel, the upper part is provided with a pressure regulating gauge and connected to the air pump 320, and the bottom is connected to the synchronous grouting pipeline 330 and the backwall grouting pipeline 340; the slurry flows to the synchronous grouting pipeline 330 or the backwall grouting pipeline 340 under stable air pressure; the synchronous grouting pipeline 330 is connected to the synchronous grouting hole 130-1 in the simulated shield shell 130 (the connection position is located at the end of the synchronous grouting hole 130-1 facing outside the test box), the slurry flows out of the grouting tank 310 under pressure, enters the synchronous grouting hole 130-1 in the simulated shield shell 130 through the synchronous grouting pipeline 330, and is injected into the tail gap 150 from the other end of the synchronous grouting hole 130-1. Among them, the synchronous grouting pipeline 330 is connected to the synchronous grouting hole 130-1, the backwall grouting pipeline 340 is connected to the backwall grouting hole 120-1, the synchronous grouting pipeline 330 and the backwall grouting pipeline 340 are both provided with valves, and the pipelines are soft tubes. The pipelines in this embodiment play a role in demonstration, and the installation position can be adjusted according to the actual installation situation.

[0084] As a specific embodiment, as shown in Figure 11 As shown, the measurement system 4 includes a soil pressure sensor 5 provided in the test soil layer 140 for measuring soil pressure, a pore water pressure sensor 6 provided in the test soil layer 140 for measuring pore water pressure, a weighing plate 410 provided at the bottom of the grouting tank 310 for measuring the weight change of the grouting tank 310, and a recorder 420 for collecting data information. Specifically, the recorder 420 is connected to a power supply, and the recorder 420 is used to receive data transmitted from the soil pressure sensor 5, the pore water pressure sensor 6, and the weighing plate 420. The measurement system 4 in this embodiment can use conventional commercially available equipment, which is not innovative and will not be described in detail here.

[0085] Example 2

[0086] A slurry shield synchronous grouting test method using the simulated test device in Example 1, specifically including the following steps:

[0087] (1) The simulated shield shell 130 is arranged on the upper part of the simulated lining 120 in the tank body 110 of the test box 1, and the backwall grouting hole 120-1 of the simulated lining 120 is blocked;

[0088] (2) Connect the simulation shield 130 with the traction system 2; specifically, according to the traction direction, the reaction force rod 250 is installed between the box body 110 of the test box 1 and the servo electric cylinder 210 (threaded connection), the traction rod 250 is installed on the simulation shield 130 and the traction plate 240 (threaded connection), and the traction plate 240 is connected with the telescopic rod 230 of the servo electric cylinder 210 through a flange or a thread;

[0089] (3) Form the test soil layer 140 above the simulation shield 130 by using the layered filling and compaction method, and bury the earth pressure sensor 5 and the pore water pressure sensor 6 in the soil when filling the soil; after the filling of the soil is completed, a flat plate is placed on the surface of the soil, and a load is stacked on the flat plate;

[0090] (4) Install the grouting tank 310 on the weighing plate 410 and inject the mud, and install the air pump 320;

[0091] (5) Connect the earth pressure sensor 5, the pore water pressure sensor 6, the weighing plate 410 and the recorder 420;

[0092] (6) As shown in FIG. 2, set the telescopic speed of the servo electric cylinder 210 and the grouting pressure according to the test purpose, open the synchronous grouting pipeline 330, and make the simulation shield 130 be pulled out of the box body 110 at the set speed while the mud is injected into the shield tail gap 150 through the synchronous grouting pipeline 330; Figures 12-13

[0093] (7) After the simulation shield 130 is pulled for a distance, the servo electric cylinder 210 and the synchronous grouting pipeline 330 are closed at the same time, the pore water pressure, the earth pressure data and the weight change data of the grouting tank 310 are copied from the recorder 420, and after the grouting slurry is solidified, the grouting body is taken out of the test box to observe the diffusion.

[0094] Example 3

[0095] A slurry shield synchronous grouting and post-wall grouting test method, using the simulation test device in Example 1, after the synchronous grouting grouting slurry is solidified, the post-wall grouting test is carried out, the synchronous grouting method uses the method of Example 2, specifically, comprising the following steps:

[0096] (1) Open the post-wall grouting hole 120-1 of the simulation lining 120, use a drilling machine to drill a hole from the bottom of the box body 110 of the test box 1 upwards, through the post-wall grouting hole 120-1 and the grouting body of the synchronous grouting, and into the test soil layer 140;

[0097] (2) Install the grouting structure 160 in the hole, specifically, insert the grouting rod 162 into the test soil layer 140, and connect the grouting head 161 with the post-wall grouting pipeline 340;

[0098] ​(3) opening the post-wall grouting pipeline 340 to start the test, and closing the post-wall grouting pipeline 340 after the test is completed;

[0099] (4) copying the pore water pressure data, the soil pressure data and the data of the weight change of the grouting tank 310 through the recorder 420, and taking out the grouting body from the test box 1 to observe the diffusion after the slurry coagulates.

[0100] Example 4

[0101] A slurry shield post-wall grouting test method, using the simulation test device in Example 1, specifically comprising the following steps:

[0102] (1) setting the simulation shield 130 in the upper part of the simulation lining 120 in the box body 110 of the test box 1;

[0103] (2) connecting the simulation shield 130 with the traction system 2;

[0104] (3) forming the test soil layer 140 above the simulation shield 130 in a layered filling and compaction manner, and burying the soil pressure sensor 5 and the pore water pressure sensor 6 when filling;

[0105] (4) installing the grouting tank 310 on the weighing plate 410 and injecting the slurry, and installing the air pump 320;

[0106] (5) connecting the soil pressure sensor 5, the pore water pressure sensor 6, the weighing plate 410 and the recorder 420;

[0107] (6) using the servo electric cylinder 210 to pull the simulation shield 130 towards the direction of the servo electric cylinder 210 to expose the post-wall grouting hole 120-1 of the simulation lining 120;

[0108] (7) drilling upward from the post-wall grouting hole 120-1 of the simulation lining 120 and into the test soil layer 140 after passing through the shield tail gap 150;

[0109] (8) installing the grouting structure 160 in the hole, specifically inserting the grouting rod 162 (the number of grouting rods 162 can be selected according to the required length) into the test soil layer 140, and connecting the grouting head 161 with the post-wall grouting pipeline 340;

[0110] (9) opening the post-wall grouting pipeline 340 to start the test, and closing the post-wall grouting pipeline 340 after the test is completed;

[0111] (10) copying the pore water pressure data, the soil pressure data and the data of the weight change of the grouting tank 310 through the recorder 420, and taking out the grouting body from the test box 1 to observe.

[0112] Using the device and method of the embodiment, the synchronous grouting and the post-wall grouting modes of the shield under different tunneling speeds, different grouting flow rates and different ground loads can be simulated; the soil pressure, the pore water pressure and the grouting flow rate data generated in the experiment process can be measured and recorded in real time, the tunneling speed-grouting pressure-soil pressure-pore water pressure relationship can be obtained through further analysis, the expansion of the grouting body in the soil can be observed after the grouting body is taken out after the grout is coagulated at the end of the experiment, and finally the parameter regulation and control related to the post-wall grouting of the shield is guided to a certain extent.

[0113] The above is only a preferred embodiment of the present application, and does not limit the present application in any form. Although the present application has been disclosed as above with a preferred embodiment, it is not intended to limit the present application. Any person skilled in the art can make some changes or modifications to the above disclosed technical content to obtain equivalent embodiments with equivalent changes, without departing from the technical solution of the present application. Any modification, change and modification of the above embodiments, which does not depart from the technical solution of the present application, belongs to the scope of the technical solution of the present application.

Claims

1. Test method for synchronous grouting and back-wall grouting of slurry shield, characterized by: A slurry shield synchronous grouting and behind-the-wall grouting dual-purpose simulation test device is used, and the slurry shield synchronous grouting and behind-the-wall grouting dual-purpose simulation test device comprises: A test box (1) for simulating a shield environment, wherein a stacked simulated lining (120) and a simulated shield shell (130) are provided in the test box (1), and a compacted test soil layer (140) simulating soil is provided above the simulated shield shell (130); A traction system (2) for traction of the simulated shield shell (130) to slide on the simulated lining (120) and to simulate a shield tail gap (150) at the tail of the simulated shield shell (130); A grouting system (3) for grouting a simulated shield tail gap (150) within the test chamber (1); as well as A measurement system (4) for obtaining parameters related to simultaneous grouting and / or back-wall grouting of a simulated slurry shield; The traction system (2) includes a servo electric cylinder (210) arranged on the outer wall of the box body (110) of the test box (1) and used to pull the simulated shield shell (130) to simulate the shield tail gap (150) at the tail of the simulated shield shell (130); The grouting system (3) comprises a grouting tank (310) for holding slurry, An air pump (320) for increasing the pressure in the grouting tank (310), A synchronous grouting pipeline (330) provided on the grouting tank (310) for conveying slurry in the grouting tank (310) to the shield tail gap (150) for synchronous grouting, and a behind-the-wall grouting pipeline (340) for behind-the-wall grouting; The simulated shield shell (130) is arranged on the upper part of the simulated lining (120); a synchronous grouting hole (130-1) for grouting into the shield tail gap (150) is arranged in the simulated shield shell (130); and a back-wall grouting hole (120-1) for back-wall grouting is arranged on the simulated lining (120). A rear wall grouting structure (160) can be installed in the rear wall grouting hole (120-1). The rear wall grouting structure (160) includes a grouting head (161) and a grouting rod (162). When in use, the grouting rod (162) is connected to the grouting head (161). The number of grouting rods (162) can be selected according to the specific use scenario. The top of the simulated lining (120) is a curved surface, and the bottom is a flat surface. The top and bottom surfaces of the simulated shield (130) are both curved surfaces. The simulated shield (130) is installed on the simulated lining (120) and can slide relative to the simulated lining (120). The lower curved surface of the simulated shield (130) is fitted with the upper curved surface of the simulated lining (120). After the simultaneous grouting slurry solidifies, the back-wall grouting test is carried out; The synchronous grouting test method of the slurry shield specifically includes the following steps: (1) placing a simulated shield (130) on the upper portion of a simulated lining (120) in a box body (110) of a test box (1), and sealing a rear grouting hole (120-1) of the simulated lining (120); (2) connecting the simulated shield (130) to the traction system (2); (3) forming a test soil layer (140) above the simulated shield (130) by filling and compacting the soil in layers, and burying a soil pressure sensor (5) and a pore water pressure sensor (6) during the filling process; (4) Install the grouting tank (310) on the weighing plate (410) and inject slurry, and install the air pump (320); (5) Connecting the soil pressure sensor (5), the pore water pressure sensor (6), the weighing plate (410) and the recorder (420); (6) setting the extension and retraction speed and grouting pressure of the servo electric cylinder (210) according to the test purpose, opening the synchronous grouting pipeline (330), so that the simulated shield shell (130) is pulled out of the box body (110) at the set speed and grouting is simultaneously performed into the shield tail gap (150) through the synchronous grouting pipeline (330); (7) After the simulated shield (130) is pulled for a certain distance, the servo electric cylinder (210) and the synchronous grouting pipeline (330) are closed simultaneously, and the pore water pressure, soil pressure data and weight change data of the grouting tank (310) are copied from the recorder (420). After the grouting slurry solidifies, the grouting body is taken out of the test box to observe the diffusion condition; The slurry shield synchronous grouting and back-wall grouting test method specifically includes the following steps: (1) Open the back-wall grouting hole (120-1) of the simulated lining (120), use a drill to drill upward from the bottom of the box body (110) of the test box (1), and then drive the grouting hole (120-1) and the synchronous grouting body into the test soil layer (140); (2) Installing a back-wall grouting structure (160) in the hole, specifically, inserting a grouting rod (162) into the test soil layer (140), and connecting a grouting head (161) to a back-wall grouting pipeline (340); (3) opening the back-wall grouting pipeline (340) to start the test, and closing the back-wall grouting pipeline (340) after the test is completed; (4) The pore water pressure data, soil pressure data and weight change data of the grouting tank (310) are copied through the recorder (420). After the slurry solidifies, the grouting body is taken out from the test box (1) to observe the diffusion condition.

2. The slurry shield synchronous grouting and back-wall grouting test method according to claim 1, characterized in that: A plurality of soil pressure sensors (5) and a plurality of pore water pressure sensors (6) are provided in the test soil layer (140). During the test, a load simulating pressure is provided to the test soil layer (140) above the test soil layer (140) as required.

3. The slurry shield synchronous grouting and back-wall grouting test method according to claim 1, characterized in that: The traction system (2) further comprises a reaction rod (220) fixed between the box (110) and the servo electric cylinder (210); a traction plate (240) arranged at the distal end of the telescopic rod (230) of the servo electric cylinder (210); and a plurality of traction rods (250) fixed between the traction plate (240) and the simulated shield (130).

4. The slurry shield synchronous grouting and back-wall grouting test method according to claim 1, characterized in that: The measuring system (4) further comprises a weighing plate (410) arranged at the bottom of the grouting tank (310) for measuring weight changes of the grouting tank (310) and a recorder (420) for collecting data information.

5. The slurry shield wall back grouting test method is characterized by: A slurry shield synchronous grouting and behind-the-wall grouting dual-purpose simulation test device is used, and the slurry shield synchronous grouting and behind-the-wall grouting dual-purpose simulation test device comprises: A test box (1) for simulating a shield environment, wherein a stacked simulated lining (120) and a simulated shield shell (130) are provided in the test box (1), and a compacted test soil layer (140) simulating soil is provided above the simulated shield shell (130); A traction system (2) for traction of the simulated shield shell (130) to slide on the simulated lining (120) and to simulate a shield tail gap (150) at the tail of the simulated shield shell (130); A grouting system (3) for grouting a simulated shield tail gap (150) within the test chamber (1); as well as A measurement system (4) for obtaining parameters related to simultaneous grouting and / or back-wall grouting of a simulated slurry shield; The traction system (2) includes a servo electric cylinder (210) arranged on the outer wall of the box body (110) of the test box (1) and used to pull the simulated shield shell (130) to simulate the shield tail gap (150) at the tail of the simulated shield shell (130); The grouting system (3) comprises a grouting tank (310) for holding slurry, An air pump (320) for increasing the pressure in the grouting tank (310), A synchronous grouting pipeline (330) provided on the grouting tank (310) for conveying slurry in the grouting tank (310) to the shield tail gap (150) for synchronous grouting, and a behind-the-wall grouting pipeline (340) for behind-the-wall grouting; The simulated shield shell (130) is arranged on the upper part of the simulated lining (120); a synchronous grouting hole (130-1) for grouting into the shield tail gap (150) is arranged in the simulated shield shell (130); and a back-wall grouting hole (120-1) for back-wall grouting is arranged on the simulated lining (120). A rear wall grouting structure (160) can be installed in the rear wall grouting hole (120-1). The rear wall grouting structure (160) includes a grouting head (161) and a grouting rod (162). When in use, the grouting rod (162) is connected to the grouting head (161). The number of grouting rods (162) can be selected according to the specific use scenario. The top of the simulated lining (120) is a curved surface, and the bottom is a flat surface. The top and bottom surfaces of the simulated shield (130) are both curved surfaces. The simulated shield (130) is installed on the simulated lining (120) and can slide relative to the simulated lining (120). The lower curved surface of the simulated shield (130) is fitted with the upper curved surface of the simulated lining (120). The slurry shield wall post-grouting test method specifically comprises the following steps: (1) A simulated shield (130) is arranged on the upper portion of a simulated lining (120) in a box body (110) of a test box (1); (2) connecting the simulated shield (130) to the traction system (2); (3) forming a test soil layer (140) above the simulated shield (130) by filling and compacting the soil in layers, and burying a soil pressure sensor (5) and a pore water pressure sensor (6) during the filling process; (4) Install the grouting tank (310) on the weighing plate (410) and inject slurry, and install the air pump (320); (5) Connecting the soil pressure sensor (5), the pore water pressure sensor (6), the weighing plate (410) and the recorder (420); (6) Using the servo electric cylinder (210) to pull the simulated shield shell (130) toward the servo electric cylinder (210) to expose the back wall grouting hole (120-1) of the simulated lining (120); (7) Drill upward from the grouting hole (120-1) behind the simulated lining (120), pass through the shield tail gap (150), and then drive into the test soil layer (140); (8) Installing a grouting structure (160) in the hole, specifically, inserting a grouting rod (162) into the test soil layer (140), and connecting a grouting head (161) to a grouting pipeline (340) behind the wall; (9) opening the back-wall grouting pipeline (340) to start the test, and closing the back-wall grouting pipeline (340) after the test is completed; (10) The pore water pressure data, soil pressure data and weight change data of the grouting tank (310) are copied through the recorder (420), and the grouting body is taken out from the test box (1) for observation after the slurry solidifies.

6. The slurry shield wall back grouting test method according to claim 5, characterized in that: A plurality of soil pressure sensors (5) and a plurality of pore water pressure sensors (6) are provided in the test soil layer (140). During the test, a load simulating pressure is provided to the test soil layer (140) above the test soil layer (140) as required.

7. The slurry shield wall back grouting test method according to claim 5, characterized in that: The traction system (2) further comprises a reaction rod (220) fixed between the box (110) and the servo electric cylinder (210); a traction plate (240) arranged at the distal end of the telescopic rod (230) of the servo electric cylinder (210); and a plurality of traction rods (250) fixed between the traction plate (240) and the simulated shield (130).

8. The slurry shield wall back grouting test method according to claim 5, characterized in that: The measuring system (4) further comprises a weighing plate (410) arranged at the bottom of the grouting tank (310) for measuring weight changes of the grouting tank (310) and a recorder (420) for collecting data information.

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