A pipe jacking test device and method thereof

Abstract

The present invention relates to the technical field of tunnel engineering, and specifically discloses a pipe jacking method test device and method thereof, comprising a pipe jacking bracket, a pipe jacking machine is arranged on the pipe jacking bracket, the pipe jacking machine comprises a cutter head, a drive system and a motor, the cutter head is provided with a cutting blade, and the pipe jacking machine is connected to a control terminal; it also comprises a rear pipe jacking section, the pipe jacking machine and the rear pipe jacking section are connected by a dynamometer; the rear pipe jacking section is provided with evenly arranged grouting holes, and the grouting holes are connected to a grouting device through a grouting pipeline for injection of friction-reducing mud; it also comprises a test box, the test box is filled with model soil, circular openings are arranged on both sides of the test box, a sealing device is installed on the circular opening on one side, the pre-jacking channel of the pipe jacking machine and the rear pipe jacking section is a channel between two circular openings in the model soil, and a plurality of soil pressure sensors are installed around the pre-jacking channel. The present invention is used to provide data support for the corresponding friction resistance, soil pressure and deformation under different friction-reducing mud ratios during the jacking process of the pipe jacking machine.

Description

Technical Field

[0001] The invention relates to the technical field of tunnel engineering, and in particular to a pipe jacking test device and a method thereof. Background Art

[0002] Pipe jacking is a trenchless construction method currently in use. It can cross existing roads, railways, rivers, underground pipelines, underground structures and cultural relics without excavating the surface layer. Pipe jacking has the following advantages: avoiding excavation of urban roads, reducing a large amount of earthwork, reducing demolition and resettlement, saving construction land, reducing interference with the surrounding environment, and not interrupting ground traffic and logistics transportation activities. In recent years, it has been widely used in urban underground space development, underground railway rail transit construction and municipal tunnel projects.

[0003] At present, for pipe jacking projects under complex engineering geological conditions, the existing relevant theories are difficult to accurately predict the interaction between force and deformation. There is also a lack of data on the corresponding friction reduction effect, friction resistance, soil pressure, deformation, etc. under different ratios of friction-reducing muds. In addition, simple field tests are often uncertain and random and difficult to repeat. Summary of the invention

[0004] The object of the present invention is to provide a pipe jacking test device and method thereof, which provide data support for the corresponding friction resistance, soil pressure and deformation under different friction-reducing mud ratios during the jacking process of the pipe jacking machine.

[0005] In order to solve the above technical problems, the technical solutions adopted by the present invention are as follows: A pipe jacking method test device comprises a pipe jacking bracket, on which a pipe jacking machine is arranged, the pipe jacking machine comprises a cutter head, a drive system and a motor, the cutter head is provided with a cutting blade, and the pipe jacking machine is connected to a control terminal; it also comprises a rear pipe jacking section, the pipe jacking machine and the rear pipe jacking section are connected via a dynamometer; the rear pipe jacking section is provided with evenly arranged grouting holes, and the grouting holes are connected to a grouting device via a grouting pipe for injecting friction-reducing mud; it also comprises a test box, the test box is filled with model soil, circular openings are respectively arranged on both sides of the test box, a sealing device is installed on the circular opening on one side, a pre-jacking channel of the pipe jacking machine and the rear pipe jacking section is a channel between two circular openings in the model soil, and a plurality of soil pressure sensors are installed around the pre-jacking channel; it also comprises a monitoring system, the monitoring system comprises a surface deformation monitoring system arranged on the top of the test box and a stress monitoring system arranged on the side wall of the test box.

[0006] Furthermore, the sealing device is in the shape of a ring, and a protrusion corresponding to the mounting hole is provided on one side of the sealing device, and a small groove is provided on the protrusion, and the small groove is used to clamp the mounting hole; the inner ring of the sealing device fits the outer wall of the jacking machine and the rear jacking pipe section to complete the sealing.

[0007] Furthermore, there are three groups of soil pressure sensors, which are respectively arranged above and below the front end, rear end and middle part of the pre-jacking channel to detect the changes in the model soil pressure when the jacking machine and the rear jacking pipe section pass through the model soil.

[0008] Furthermore, the cutter disc is provided with a discharge port for discharging slag during the test.

[0009] Furthermore, the driving system is provided with an electric servo loading system, which changes the excavation power of the pipe jacking machine by adjusting the input power through the control terminal, thereby changing the jacking state of the rear pipe jacking section.

[0010] The present invention also provides a test method for a pipe jacking test device, comprising the following steps: Step S1: connecting the pipe jacking machine, the dynamometer, and the rear pipe jacking section in sequence through connecting bolts, and placing them on the pipe jacking bracket; Step S2: pouring friction-reducing mud into the grouting device; Step S3: Control the drive system at the control terminal to drive the cutter head to rotate and cut forward, and provide pulling force for the rear jacking pipe to drive the rear jacking pipe section to push forward, and at the same time, perform artificial slag removal and injection of friction-reducing mud; Step S4: Continue to push the pipe jacking machine and continue to inject the friction-reducing mud until the rear pipe jacking section is completely pushed into the test box, during which the data changes of the dynamometer, soil pressure sensor, surface deformation monitoring system and stress monitoring system are recorded.

[0011] Furthermore, step S5 is also included: repeating steps S1 to S4, adjusting the input power by the control terminal to change the excavation power of the drive system, changing the jacking state of the rear jacking pipe section, using different friction-reducing muds, repeating multiple times, testing the friction-reducing effect of the friction-reducing mud, and the changes in soil pressure, surface deformation, and surrounding rock stress over time.

[0012] Compared with the prior art, the present invention has the following advantages and beneficial effects: 1. The pipe jacking machine provides power through the driving system to drive the rear pipe jacking section forward, replacing the double-tube method used in the traditional pipe jacking test. The use of the pipe jacking machine provides visual and stable tension, so that the rear pipe jacking section will not deviate during jacking, and it is easy to jack the rear pipe jacking section, thereby improving the accuracy of the test.

[0013] 2. The driving system in the pipe jacking machine is connected to the control terminal, through which the parameters of the pipe jacking machine can be controlled and adjusted, thereby changing the jacking state of the rear jacking pipe section. Through multiple tests, different pulling forces and jacking speeds are changed to provide practical guidance for pipe jacking construction.

[0014] 3. The jacking machine and the rear jacking pipe section are connected by a dynamometer. The dynamometer is used to detect the friction resistance encountered by the rear jacking pipe section during the jacking process, and the friction force between the rear jacking pipe section and the model soil is accurately obtained. The friction force is used to determine the optimal ratio of the friction-reducing mud, and thus the thrust force required for jacking can be determined. BRIEF DESCRIPTION OF THE DRAWINGS

[0015] Figure 1 It is the overall structural diagram of the test device of the present invention.

[0016] Figure 2 Schematic diagram of pipe jacking machine.

[0017] Figure 3 Schematic diagram of the cutter disc structure of the pipe jacking machine.

[0018] Figure 4 The figure shows the side view of the test chamber.

[0019] Figure 5 Schematic diagram of the sealing device structure.

[0020] Figure 6 It is a schematic diagram of the connection structure of the grouting process in the present invention.

[0021] The meanings of the numbers in the figure are: 1-test box, 2-model soil, 3-surface deformation monitoring system, 4-stress monitoring system, 5-soil pressure sensor, 6-pipe jacking machine, 61-cutter head, 611-cutting blade, 612-discharge port, 62-drive system, 63-motor, 64-connecting bolt, 7-control terminal, 8-dynamometer, 9-rear jacking pipe section, 10-jacking bracket, 11-grouting port, 12-grouting pipe, 13-grouting device, 14-sealing device, 141-protrusion. DETAILED DESCRIPTION

[0022] The technical scheme in the embodiments of the present invention will be clearly and completely described below in conjunction with the accompanying drawings in the embodiments of the present invention, so as to have a further understanding of the concept of the present invention, the technical problems solved, the technical features constituting the technical scheme and the technical effects brought about.

[0023] like Figure 1 , Figure 2 , Figure 4 , Figure 6As shown, a pipe jacking method test device includes a pipe jacking bracket 10, on which a pipe jacking machine 6 is arranged, the pipe jacking machine 6 includes a cutter head 61, a drive system 62 and a motor 63, the cutter head 61 is provided with a cutting blade 611, and the pipe jacking machine 6 is connected to a control terminal 7; it also includes a rear pipe jacking section 9, the pipe jacking machine 6 and the rear pipe jacking section 9 are connected through a dynamometer 8; the front end of the rear pipe jacking section 9 is provided with grouting holes arranged evenly, and the grouting holes are connected to a grouting device 13 through a grouting pipe 12 for friction reduction The invention also includes a test box 1, which is filled with a model soil 2. Circular openings are respectively arranged on both sides of the test box 1, and a sealing device 14 is installed on the circular opening on one side. The pre-jacking channel of the jacking machine 6 and the rear jacking pipe section 9 is the channel between the two circular openings in the model soil 2, and a plurality of soil pressure sensors 5 are installed around the pre-jacking channel; the monitoring system also includes a surface deformation monitoring system 3 arranged on the top of the test box 1 and a stress monitoring system 4 arranged on the side wall of the test box 1.

[0024] The present invention is used to simulate the construction of pipe jacking, analyze the influence of different mud ratios used for grouting of friction-reducing mud during pipe jacking on the jacking force, the influence on the ground deformation, the influence on the surrounding rock stress and the influence on the soil pressure. For example, in the pipe jacking construction of subway communication channels in offshore water-rich soft strata, due to the lack of sufficient reference, a simulation test is required. In the present invention, the pipe jacking machine 6 controls the motor 63 through the drive system 62 to provide power, driving the rear pipe jacking section 9 to jack forward, replacing the double-tube method used in the traditional pipe jacking test. The use of the pipe jacking machine 6 to provide a visual and stable tension force prevents the rear pipe jacking section 9 from deflecting during jacking, and facilitates the jacking of the rear pipe jacking section 9, thereby improving the accuracy of the test. The pipe jacking machine 6 is provided with a cutter head 61, and the driving system 62 in the pipe jacking machine 6 is connected to the control terminal 7. The parameters of the pipe jacking machine 6 can be controlled and adjusted through the control terminal 7, so that the jacking state of the rear jacking pipe section 9 can be changed. Through multiple tests, different pulling forces and jacking speeds are changed to provide practical guidance for the jacking construction. The pipe jacking machine 6 and the rear jacking pipe section 9 are connected by a dynamometer 8. The dynamometer 8 is used to detect the friction resistance of the rear jacking pipe section 9 during the jacking process, and the friction between the rear jacking pipe section 9 and the model soil 2 is accurately obtained. The friction is used to determine the optimal ratio of the friction-reducing mud, so that the jacking thrust required for the jacking can also be determined, which can provide effective guidance for the actual construction. A grouting pipe 12 is provided inside the rear jacking pipe section 9, and one end of the grouting pipe 12 is connected to the grouting port 11, and the other end extends from the side of the rear rectangular jacking pipe away from the test box 1 and is connected to the grouting device 13, so that the friction-reducing mud can be better injected and diffused.

[0025] like Figure 5As shown, further, the sealing device 14 is in a circular ring shape, and a protrusion 141 corresponding to the mounting hole is provided on one side of the sealing device 14, and a small groove is provided on the protrusion 141, and the small groove is used to clamp the mounting hole; the inner ring of the sealing device 14 fits the outer wall of the jacking machine 6 and the rear jacking pipe section 9 to complete the sealing. After the sealing is completed, the problem of uncontrollable grouting pressure caused by slurry leakage is solved, and stable pressure grouting drag reduction is achieved.

[0026] Furthermore, there are three groups of soil pressure sensors 5, which are respectively arranged above and below the front end, rear end and middle of the pre-jacking channel, and are used to detect the pressure changes of the model soil 2 when the jacking machine 6 and the rear jacking pipe section 9 pass through.

[0027] like Figure 3 As shown, further, the cutter disc 61 is provided with a discharge port 612 for discharging slag during the test.

[0028] Furthermore, the driving system 62 is provided with an electric servo loading system, which changes the excavation power of the pipe jacking machine 6 by adjusting the input power through the control terminal 7, thereby changing the jacking state of the rear pipe jacking section 9.

[0029] The present invention provides a test method for a pipe jacking test device, comprising the following steps: Step S1: The pipe jacking machine 6, the dynamometer 8, and the rear pipe jacking section 9 are sequentially connected by connecting bolts 64, and placed on the pipe jacking bracket 10; Step S2: pouring friction-reducing mud into the grouting device 13; Step S3: Control the drive system 62 at the control terminal 7, so that the drive system 62 drives the cutter head 61 to rotate and cut forward, and provides a pulling force for the rear jacking pipe, drives the rear jacking pipe section 9 to push forward, and performs artificial slag removal and injection of friction-reducing mud at the same time; Step S4: Continue to push the pipe jacking machine 6 and continue to inject the friction-reducing mud until the rear pipe jacking section 9 is completely pushed into the test box 1, during which the data changes of the dynamometer 8, the earth pressure sensor 5, the surface deformation monitoring system 3 and the stress monitoring system 4 are recorded.

[0030] According to the data during the jacking process of the pipe jacking machine 6, data support is provided for the pipe jacking construction.

[0031] Furthermore, step S5 is also included: repeating steps S1 to S4, adjusting the input power through the control terminal 7 to change the excavation power of the drive system 62, changing the jacking state of the rear jacking pipe section 9, using different friction-reducing muds, repeating multiple times, and testing the friction-reducing effect of the friction-reducing mud, and the changes of soil pressure, surface deformation, and surrounding rock stress over time. Repeating steps S1 to S4, connecting the electric servo loading system provided by the drive system 62 of the jacking machine 6 to the control terminal 7, adjusting the input power through the control terminal 7 to change the excavation power of the jacking machine 6, thereby changing the jacking state of the rear jacking pipe section 9, using different friction-reducing muds, and testing the friction-reducing effect of the friction-reducing mud, and the changes of soil pressure, surface deformation, and surrounding rock stress over time through multiple tests. Provide practical guidance for jacking construction. Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit it. Although the present invention has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that the technical solutions described in the aforementioned embodiments can still be modified, or some or all of the technical features therein can be replaced by equivalents. However, these modifications or replacements do not make the essence of the corresponding technical solutions deviate from the scope of the technical solutions of the embodiments of the present invention.

Claims

1. A pipe jacking test device, characterized in that: The invention comprises a pipe jacking bracket (10), a pipe jacking machine (6) is arranged on the pipe jacking bracket (10), the pipe jacking machine (6) comprises a cutter head (61), a drive system (62) and a motor (63), the cutter head (61) is provided with a cutting blade (611), and the pipe jacking machine (6) is connected to a control terminal (7); and further comprises a rear pipe jacking section (9), the pipe jacking machine (6) and the rear pipe jacking section (9) being connected via a dynamometer (8); The rear top pipe section (9) is provided with evenly arranged grouting holes, and the grouting holes are connected to a grouting device (13) through a grouting pipeline (12) for injection of friction-reducing slurry; It also includes a test box (1), the test box (1) is filled with model soil (2), circular openings are respectively arranged on both sides of the test box (1), and a sealing device (14) is installed on the circular opening on one side, and a pre-jacking channel of the jacking machine (6) and the rear jacking pipe section (9) is a channel between two circular openings in the model soil (2), and a plurality of soil pressure sensors (5) are installed around the pre-jacking channel; It also includes a monitoring system, which includes a surface deformation monitoring system (3) arranged on the top of the test box (1) and a stress monitoring system (4) arranged on the side wall of the test box (1).

2. A pipe jacking test device according to claim 1, characterized in that: The sealing device (14) is annular, and a protrusion (141) corresponding to the mounting hole is provided on one side of the sealing device (14). A small groove is provided on the protrusion (141), and the small groove is used to clamp the mounting hole. The inner ring of the sealing device (14) fits the outer wall of the pipe jacking machine (6) and the rear pipe jacking section (9) to complete the sealing.

3. A pipe jacking test device according to claim 1, characterized in that: There are three groups of soil pressure sensors (5), which are respectively arranged above and below the front end, the rear end and the middle of the pre-jacking channel, and are used to detect the pressure change of the model soil (2) when the jacking machine (6) and the rear jacking pipe section (9) pass through the model soil (2).

4. A pipe jacking test device according to claim 1, characterized in that: The cutter disc (61) is provided with a discharge port (612) for discharging slag during the test process.

5. A pipe jacking test device according to claim 1, characterized in that: The driving system (62) is provided with an electric servo loading system, which changes the driving power of the pipe jacking machine (6) by adjusting the input power through the control terminal (7), thereby changing the jacking state of the rear pipe jacking section (9).

6. A test method for a pipe jacking test device according to claim 1, characterized in that: The following steps are involved: Step S1: connecting the pipe jacking machine (6), the dynamometer (8), and the rear pipe jacking section (9) in sequence through connecting bolts (64), and placing them on the pipe jacking bracket (10); Step S2: pouring friction-reducing mud into the grouting device (13); Step S3: Controlling the drive system (62) at the control terminal (7) so that the drive system (62) drives the cutter head (61) to rotate and cut forward, and provides a pulling force for the rear jacking pipe, driving the rear jacking pipe section (9) to push forward, and at the same time, performing artificial slag removal and injection of friction-reducing mud; Step S4: Continue to push the pipe jacking machine (6) and continue to inject the friction-reducing mud until the rear pipe jacking section (9) is completely pushed into the test box (1), during which the data changes of the dynamometer (8), the earth pressure sensor (5), the surface deformation monitoring system (3) and the stress monitoring system (4) are recorded.

7. The test method of the pipe jacking test device according to claim 6 is characterized in that: The method further includes step S5: repeating steps S1 to S4, adjusting the input power by the control terminal (7) to change the excavation power of the drive system (62), changing the jacking state of the rear jacking pipe section (9), using different friction-reducing muds, repeating the process multiple times, testing the friction-reducing effect of the friction-reducing mud, and the changes in soil pressure, surface deformation, and surrounding rock stress over time.

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