Model test device for pipe jacking resistance reduction

Abstract

The utility model provides a model test device for pipe jacking resistance reduction, and relates to the technical field of pipe jacking construction of tunnel engineering. The test device drives the U-shaped plate to move in the radial direction of the top pipe through the first jack, the second jack and the third jack so as to adjust the position of the top pipe in the mud sleeve. The jacking assembly drives the jacking pipe to jack in the axial direction, the jacking pressure sensor monitors the resistance borne by the jacking pipe in the jacking process, the slurry pressure sensor monitors the grouting pressure, the influence of the slurry proportion and the grouting pressure on the resistance reduction effect of the jacking pipe under the condition that the jacking pipe and the slurry sleeve are at various relative positions is obtained, and a basis is provided for resistance reduction optimization.

Description

TECHNICAL FIELD

[0001] The utility model relates to a tunnel engineering jacking pipe construction technical field, concretely relates to a model test device for jacking pipe drag reduction. BACKGROUND

[0002] In the field of tunnel construction, jacking pipes are usually used to advance underground in order to build underground passages, pipelines or other underground structures. However, due to factors such as geological conditions, pipeline materials, construction environment, etc., jacking pipe construction often encounters problems such as high resistance and slow progress, and the use of drag reduction mud is a key way to solve these problems.

[0003] During jacking, the most ideal position of the jacking pipe in the mud sleeve is the center, at which time the jacking pipe does not contact the surrounding soil and experiences less frictional resistance. However, the jacking pipe often deviates from the optimal position and moves away from the center of the mud sleeve, even contacting the soil. The drag reduction effect of mud in these non-ideal situations also needs to be considered.

[0004] However, there is currently a lack of test devices to simulate the jacking of jacking pipes in different positions in the mud sleeve, accurately measure data such as frictional resistance and soil pressure around the pipe, and analyze the factors affecting jacking pipe drag reduction, providing test devices and theoretical basis for subsequent optimization of jacking pipe drag reduction by adjusting factors such as mud ratio and grouting pressure. SUMMARY

[0005] In view of the deficiencies of the prior art, the utility model provides a model test device for jacking pipe drag reduction, which solves the problem of lack of test devices to simulate and analyze jacking pipe drag reduction.

[0006] To achieve the above purpose, the utility model is implemented by the following technical solutions:

[0007] A model test device for jacking pipe drag reduction, the test device comprising: a test box assembly and a jacking assembly;

[0008] The test box assembly comprises: a rear plate, a front plate, a U-shaped plate and a base;

[0009] The rear plate and the front plate are both fixed on the base, and the rear plate and the front plate are both provided with through holes for the jacking pipe to pass through;

[0010] The front and rear ends of the U-shaped plate are both provided with rubber pads; the U-shaped plate is sealed and fitted with the rear plate and the front plate through the corresponding rubber pads;

[0011] First, second and third jacks are arranged below and on both sides of the U-shaped plate; the first jack is installed on the base, and the second and third jacks are both installed on the base through support plates;

[0012] The jacking assembly comprises a servo jack and a jacking pressure sensor.

[0013] The servo jack is used to drive the jacking of the jacking pipe along the through hole in the axial direction, and the jacking pressure sensor is used to monitor the jacking pressure of the servo jack in real time.

[0014] Preferably, the through hole of the rear plate is provided with a first water stop rubber ring, and the through hole of the front plate is provided with a second water stop rubber ring.

[0015] Preferably, the U-shaped plate comprises a side plate and a bottom plate.

[0016] Both ends of the bottom plate are welded with side plates, and angle steels are welded at the connection between the side plates and the bottom plate.

[0017] Preferably, both sides of the first jack are provided with support frames.

[0018] The free ends of the first jack, the second jack and the third jack are all provided with pads.

[0019] Preferably, a gantry is mounted on the base, a fourth jack is arranged at the bottom of the cross beam of the gantry, and the fourth jack is located above the U-shaped plate.

[0020] Preferably, the jacking assembly further comprises a counterforce frame, a cushion block and a lifting frame.

[0021] The counterforce frame is fixed to the ground, the tail end of the servo jack is connected with the counterforce frame, the head end of the servo jack is in contact with the jacking pipe through the cushion block, and the sensing part of the jacking pressure sensor is arranged between the servo jack and the cushion block.

[0022] The top of the lifting frame is provided with a roller way, and the lifting frame supports the jacking pipe through the roller way.

[0023] Preferably, the jacking pipe comprises a front pipe and a rear pipe.

[0024] The front pipe and the rear pipe are coaxially welded, and the outer diameter of the front pipe is larger than that of the rear pipe.

[0025] The first water stop rubber ring is used for the passing of the rear pipe and keeping water stop, and the second water stop rubber ring is used for the passing of the front pipe and keeping water stop.

[0026] Preferably, the test device further comprises a grouting assembly.

[0027] The grouting assembly comprises a grouting pipe, a slurry storage tank and an air compressor.

[0028] The pipe wall of the rear pipe is provided with a plurality of grouting holes, the grouting holes are connected with the grouting pipe through a plurality of series-connected six-way pipes, the head end of the grouting pipe extends into the slurry storage tank, and the air compressor is used to press the slurry in the slurry storage tank to the outside of the pipe wall of the rear pipe along the grouting pipe, the six-way pipe and the grouting hole.

[0029] Preferably, the head end of each six-way pipe is provided with an electromagnetic valve; and the grouting pipe is provided with a slurry pressure sensor.

[0030] The utility model provides a model test device for pipe jacking resistance reduction, which has the following beneficial effects compared with the prior art:

[0031] In the utility model, the test device drives the U-shaped plate to move along the radial direction of the pipe by the first jack, the second jack and the third jack, so as to adjust the position of the pipe in the slurry sleeve; the jacking assembly drives the pipe to jacking along the axial direction, the jacking pressure sensor monitors the resistance received by the pipe during jacking, and the slurry pressure sensor monitors the grouting pressure, so as to obtain the influence of the slurry ratio and the grouting pressure on the pipe resistance reduction effect under various relative positions between the pipe and the slurry sleeve, and provide a basis for resistance reduction optimization. BRIEF DESCRIPTION OF DRAWINGS

[0032] In order to more clearly illustrate the technical scheme in the embodiments of the utility model or the prior art, the drawings needed to be used in the embodiment or the prior art description will be briefly introduced below, and obviously, the drawings in the following description are only some embodiments of the utility model, and for those skilled in the art, other drawings can also be obtained according to these drawings without creative labor.

[0033] Figure 1 It is a structural schematic view of the test device in the embodiment of the utility model;

[0034] Figure 2 It is a structural schematic view of the test box assembly in the embodiment of the utility model;

[0035] Figure 3 It is an explosion view of the test box assembly in the embodiment of the utility model;

[0036] Figure 4 It is an explosion view of the rear plate, the front plate and the U-shaped plate in the embodiment of the utility model;

[0037] Figure 5 It is a structural schematic view of the rear plate and the front plate in the embodiment of the utility model;

[0038] Figure 6 It is a structural schematic view of the U-shaped plate in the embodiment of the utility model;

[0039] Figure 7 It is a partial structural schematic view of the test box assembly in the embodiment of the utility model;

[0040] Figure 8 It is a position change schematic view of the U-shaped plate in the embodiment of the utility model;

[0041] Figure 9 It is a structure schematic view of the lifting frame in the embodiment of the utility model;

[0042] Figure 10 It is a structure schematic view of the jacking pipe in the embodiment of the utility model;

[0043] Figure 11 It is a structure schematic view of the six-way pipe in the embodiment of the utility model;

[0044] Figure 12 It is a partial structure schematic view of the test device after the mud sleeve is generated in the embodiment of the utility model;

[0045] Figure 13 It is a structure schematic view of the test device in the initial state of the test in the embodiment of the utility model;

[0046] Figure 14 It is a structure schematic view of the test device after the mud sleeve is generated in the embodiment of the utility model;

[0047] Figure 15 It is a structure schematic view of the test device in the end state of the test in the embodiment of the utility model;

[0048] Figure 16 It is a relative position schematic view of the jacking pipe and the mud sleeve in the embodiment of the utility model;

[0049] The figure mark is set to: back plate 1, front plate 2, side plate 3, bottom plate 4, first water stop rubber ring 5, second water stop rubber ring 6, rubber pad 7, oblique support 8, first jack 9, second jack 10, third jack 11, fourth jack 12, pad plate 13, support plate 14, support frame 15, gantry 16, mud sleeve 17, six-way pipe 18, base 19, front pipe 20, rear pipe 21, lifting frame 22, servo jack 23, cushion block 24, jacking pressure sensor 25, counterforce frame 26, grouting pipe 27, mud pressure sensor 28, slurry storage tank 29, air compressor 30. DETAILED DESCRIPTION

[0050] In order to make the purpose, technical scheme and advantages of the embodiment of the utility model more clear, the technical scheme in the embodiment of the utility model is clearly and completely described, obviously, the described embodiment is a part of the embodiment of the utility model, rather than all the embodiments. Based on the embodiment in the utility model, all other embodiments obtained by the person skilled in the art without making creative labor belong to the protection scope of the utility model.

[0051] The embodiment of the application provides a model test device for jacking pipe drag reduction, and solves the problem of lacking test devices for simulating and analyzing jacking pipe drag reduction.

[0052] To better understand the above technical solutions, the following will provide a detailed explanation of the technical solutions in conjunction with the accompanying drawings and specific implementation methods.

[0053] Example:

[0054] like Figures 1-16 As shown, this utility model provides a model test device for pipe jacking drag reduction, the test device comprising: a test chamber assembly and a jacking assembly;

[0055] The test chamber assembly includes: a rear plate 1, a front plate 2, a U-shaped plate, and a base 19;

[0056] Both the rear plate 1 and the front plate 2 are fixed on the base 19, and both the rear plate 1 and the front plate 2 are provided with through holes for the top pipe to pass through.

[0057] Rubber pads 7 are provided at both the front and rear ends of the U-shaped plate; the U-shaped plate is sealed and fitted to the rear plate 1 and the front plate 2 respectively through the corresponding rubber pads 7.

[0058] A first jack 9, a second jack 10, and a third jack 11 are respectively provided below and on both sides of the U-shaped plate; the first jack 9 is mounted on the base 19, and the second jack 10 and the third jack 11 are both mounted on the base 19 through the support plate 14; the first jack 9 is used to drive the U-shaped plate to move up and down, and the second jack 10 and the third jack 11 are used to drive the U-shaped plate to move left and right.

[0059] The jacking assembly includes: a servo jack 23 and a jacking pressure sensor 25;

[0060] The servo jack 23 is used to drive the jacking pipe to advance along the through hole axially, and the jacking pressure sensor 25 monitors the jacking pressure of the servo jack 23 in real time.

[0061] like Figure 5 As shown, the outer sides of the rear plate 1, front plate 2 and support plate 14 are all reinforced by diagonal supports 8.

[0062] like Figure 5 As shown, a first water-stop rubber ring 5 is provided in the through hole of the rear plate 1, and a second water-stop rubber ring 6 is provided in the through hole of the front plate 2.

[0063] The first water-stopping rubber ring 5, the second water-stopping rubber ring 6, and the rubber pad 7 are all coated with lubricant.

[0064] like Figure 6 As shown, the U-shaped plate includes: a side plate 3 and a bottom plate 4;

[0065] Side plates 3 are welded to both ends of the base plate 4, and angle steel is welded to the connection between the side plates 3 and the base plate 4.

[0066] likeFigure 7 、 Figure 8 As shown in the figure, the free ends of the first jack 9, the second jack 10 and the third jack 11 are provided with a pad plate 13.

[0067] The pad plate 13, the rear plate 1 and the front plate 2 are all coated with a drag-reducing coating.

[0068] As shown in the figure, Figure 7 、 Figure 8 The first jack 9 is provided with a support frame 15 on both sides, which is used to support the U-shaped plate.

[0069] As shown in the figure, Figure 7 、 Figure 8 The gantry 16 is installed on the base 19, and the crossbeam of the gantry 16 is provided with a fourth jack 12, which is located above the U-shaped plate and cooperates with the cover plate to apply a vertical load to the soil in the test box assembly.

[0070] As shown in the figure, Figure 1 、 Figure 9 The jacking assembly further comprises a counterforce frame 26, a cushion block 24 and a lifting frame 22.

[0071] The counterforce frame 26 is fixed to the ground and reinforced by diagonal braces. The tail end of the servo jack 23 is connected to the counterforce frame 26, and the head end of the servo jack 23 is in contact with the jacking pipe through the cushion block 24. The sensing element of the jacking pressure sensor 25 is arranged between the servo jack 23 and the cushion block 24.

[0072] The top of the lifting frame 22 is provided with a roller bed, and the lifting frame 22 supports the jacking pipe through the roller bed to reduce the frictional resistance between the jacking pipe and the lifting frame 22.

[0073] As shown in the figure, Figure 10 The jacking pipe comprises a front pipe 20 and a rear pipe 21.

[0074] The front pipe 20 and the rear pipe 21 are coaxially welded, and the outer diameter of the front pipe 20 is larger than that of the rear pipe 21.

[0075] The first water-stopping rubber ring 5 is provided for the rear pipe 21 to pass through and maintain water-stopping property; the second water-stopping rubber ring 6 is provided for the front pipe 20 to pass through and maintain water-stopping property.

[0076] As shown in the figure, Figure 1 、 Figure 10 、 Figure 11 The test device further comprises a grouting assembly.

[0077] The grouting assembly comprises a grouting pipe 27, a grout storage tank 29 and an air compressor 30.

[0078] The pipe wall of the rear pipe 21 is provided with a plurality of grouting holes, the grouting holes are connected with the grouting pipe 27 through a plurality of series six-way pipes 18, the head end of the grouting pipe 27 extends into the slurry storage tank 29, and the air compressor 30 is used to press the slurry in the slurry storage tank 29 to the outside of the pipe wall of the rear pipe 21 along the grouting pipe 27, the six-way pipe 18 and the grouting hole.

[0079] The head end of each section of the six-way pipe 18 is provided with an electromagnetic valve for controlling the grouting position.

[0080] As shown in Figure 1 , the grouting pipe 27 is provided with a slurry pressure sensor 28 for monitoring the grouting pressure.

[0081] As shown in Figures 12-16 , the test method of the test device includes the following steps:

[0082] S1, vaseline is applied to the inner walls of the rear plate 1 and the front plate 2, so that the subsequent U-shaped plate can be driven by the first jack 9, the second jack 10 and the third jack 11 to push the box soil to move, the test soil is layered and filled into the test box assembly and compacted, and is gradually added until below the through hole;

[0083] S2, vaseline is applied to the first water stop rubber ring 5 and the second water stop rubber ring 6, the pipe is inserted into the through hole, the rear pipe 21 keeps water stop with the first water stop rubber ring 5, the front pipe 20 keeps water stop with the second water stop rubber ring 6, the height of the lifting frame 22 is adjusted to keep the shape of the pipe, the axial position of the pipe is adjusted, until the front pipe 20 completely enters the test box assembly, the soil is continuously filled and compacted until it is filled, at this time the position of the pipe is as shown in Figure 13 ;

[0084] S3, the servo jack 23 is started, the position of the grouting hole is observed, and the grouting hole into the test box assembly is controlled by the electromagnetic valve at the head end of the six-way pipe 18 to grout to the outside of the rear pipe 21;

[0085] S4, when the front pipe 20 is completely pushed out of the test box assembly, the pushing in is paused, at this time the position of the pipe is as shown in Figure 14 , the partial enlarged view in the box is as shown in Figure 12 , the mud sleeve 17 is formed between the rear pipe 21 and the soil body, the first jack 9, the second jack 10 and the third jack 11 are operated, the soil body in the box is moved as a whole under the condition that the position of the pipe remains unchanged, and the relative position of the pipe in the mud sleeve 17 is changed, as shown in Figure 16 , A is the pipe, M is the outer wall of the mud sleeve, and B, C, D and E are the relative positions of the pipe in the mud sleeve 17 after the box soil moves;

[0086] S5, after the pipe and the mud sleeve 17 are adjusted to the measured relative position, the servo jack 23 is started to continue to push in until the test is completed, at this time the position of the pipe is as shown in Figure 15The monitoring data of the jacking pressure sensor 25 and the mud pressure sensor 28 during the jacking process are recorded, S1-S5 are repeated, the relationship between the resistance of the jacking pipe during the jacking process and the mud ratio and the grouting pressure under various relative positions of the jacking pipe and the mud sleeve 17 is obtained, and a test model is provided for the subsequent optimization of the test factors such as the mud ratio and the grouting pressure to reduce the resistance.

[0087] Compared with the prior art, the utility model has the beneficial effects that:

[0088] In the embodiment of the utility model, the test device drives the U-shaped plate to move along the radial direction of the jacking pipe through the first jack 9, the second jack 10 and the third jack 11, so as to adjust the position of the jacking pipe in the mud sleeve, the jacking assembly drives the jacking pipe to jacking along the axial direction, the jacking pressure sensor 25 monitors the resistance of the jacking pipe during the jacking process, the mud pressure sensor 28 monitors the grouting pressure, the influence of the mud ratio and the grouting pressure on the resistance reduction effect of the jacking pipe under various relative positions of the jacking pipe and the mud sleeve 17 is obtained, and a basis is provided for resistance reduction optimization.

[0089] It should be noted that, in this document, the relationship terms such as first and second are used only to differentiate one entity or operation from another entity or operation, and do not necessarily require or imply that there is any such actual relationship or order between these entities or operations. Moreover, the terms "include", "contain" or any other variants thereof are intended to cover non-exclusive inclusion, so that the process, method, article or equipment including a series of elements not only includes those elements, but also includes other elements not explicitly listed or inherent to such process, method, article or equipment. Without more limitations, the element defined by the statement "including a" does not exclude the presence of other identical elements in the process, method, article or equipment including the element.

[0090] The above embodiments are only used to illustrate the technical solutions of the utility model, and not to limit them; although the utility model has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that: it can still modify the technical solutions recorded in the foregoing embodiments, or make equivalent replacement to part of the technical features; and these modifications or replacements do not make the essence of the corresponding technical solutions deviate from the spirit and scope of the technical solutions of the embodiments of the utility model.

Claims

1. A model test device for pipe jacking drag reduction, characterized by, The test device comprises a test box assembly and a jacking assembly; The test box assembly comprises a rear plate (1), a front plate (2), a U-shaped plate and a base (19); The rear plate (1) and the front plate (2) are both fixed on the base (19), and the rear plate (1) and the front plate (2) are both provided with a through hole for the jacking pipe to pass through; The front end and the rear end of the U-shaped plate are both provided with a rubber pad (7); the U-shaped plate is sealed and attached to the rear plate (1) and the front plate (2) through the corresponding rubber pads (7); The lower side and the two sides of the U-shaped plate are respectively provided with a first jack (9), a second jack (10) and a third jack (11); the first jack (9) is installed on the base (19), and the second jack (10) and the third jack (11) are both installed on the base (19) through a support plate (14); The jacking assembly comprises a servo jack (23) and a jacking pressure sensor (25); The servo jack (23) is used to drive the jacking pipe to axially jack along the through hole, and the jacking pressure sensor (25) is used to monitor the jacking pressure of the servo jack (23) in real time.

2. The model test apparatus for pipe jacking drag reduction according to claim 1, wherein, The through hole of the rear plate (1) is provided with a first water stop rubber ring (5), and the through hole of the front plate (2) is provided with a second water stop rubber ring (6).

3. The model test apparatus for pipe jacking drag reduction according to claim 1, wherein, The U-shaped plate comprises a side plate (3) and a bottom plate (4); The two ends of the bottom plate (4) are respectively welded with the side plate (3), and an angle steel is welded at the connection between the side plate (3) and the bottom plate (4).

4. The model test apparatus for pipe jacking drag reduction according to claim 1, wherein, The two sides of the first jack (9) are provided with a support frame (15); The free ends of the first jack (9), the second jack (10) and the third jack (11) are all provided with a backing plate (13).

5. The model test apparatus for pipe jacking drag reduction according to claim 1, wherein, A gantry (16) is installed on the base (19), the bottom of the beam of the gantry (16) is provided with a fourth jack (12), and the fourth jack (12) is located above the U-shaped plate.

6. The model test apparatus for pipe jacking drag reduction according to claim 1, wherein, The jacking assembly further comprises a counterforce frame (26), a cushion block (24) and a lifting frame (22); The counterforce frame (26) is fixed on the ground, the tail end of the servo jack (23) is connected with the counterforce frame (26), the head end of the servo jack (23) is in contact with the jacking pipe through the cushion block (24), and the sensing part of the jacking pressure sensor (25) is arranged between the servo jack (23) and the cushion block (24); The top of the lifting frame (22) is provided with a roller way, and the lifting frame (22) supports the jacking pipe through the roller way.

7. The model test apparatus for pipe jacking drag reduction according to claim 2, wherein, The jacking pipe comprises a front pipe (20) and a rear pipe (21); The front pipe (20) and the rear pipe (21) are coaxially welded, and the outer diameter of the front pipe (20) is larger than that of the rear pipe (21); The first water stop rubber ring (5) is used for the rear pipe (21) to pass through and keep water stop, and the second water stop rubber ring (6) is used for the front pipe (20) to pass through and keep water stop.

8. The model test apparatus for pipe jacking drag reduction according to claim 7, wherein, The test device further comprises a grouting assembly; The grouting assembly comprises a grouting pipe (27), a grout storage tank (29) and an air compressor (30); The pipe wall of the rear pipe (21) is provided with a plurality of grouting holes, the grouting holes are connected with grouting pipes (27) through a plurality of series-connected six-way pipes (18), the head end of the grouting pipe (27) extends into a slurry storage tank (29), and an air compressor (30) is used to press the slurry in the slurry storage tank (29) to the outside of the pipe wall of the rear pipe (21) along the grouting pipe (27), the six-way pipe (18) and the grouting hole.

9. The model test apparatus for pipe jacking drag reduction according to claim 8, wherein, The head end of each section of the six-way pipe (18) is provided with an electromagnetic valve; and the grouting pipe (27) is provided with a slurry pressure sensor (28).

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