Visual test device for shield wall back grouting slurry diffusion

Abstract

The utility model discloses a shield wall back grouting slurry diffusion visualization test device which comprises a grouting system and a grouted device, and the grouted device comprises a transparent pipe. A linear motion positioning mechanism and a slurry inlet are arranged at the front end of the transparent pipe; a pressing mechanism and a slurry outlet are arranged at the rear end of the transparent pipe; the grouting system is connected with the grout inlet through a connecting pipeline; the linear motion positioning mechanism comprises a positioning piston, the positioning piston can seal the transparent tube, and the positioning piston does not shield the slurry inlet after retracting to the bottom; the pressing mechanism comprises a slurry penetrating piston, and slurry can penetrate through the slurry penetrating piston. According to the utility model, the filling process of slurry in the shield tail gap can be simulated, the compaction of sandy soil and the adjustment of the shield tail gap are realized through the linear motion positioning mechanism and the compaction mechanism, the positioning piston provides support for the compaction process of the sandy soil, the shield tail gap is formed, the slurry can penetrate through the slurry penetrating piston, and the slurry penetrating piston is matched with the transparent pipe. And a tester can observe the diffusion process.

Description

Technical Field

[0001] The utility model relates to the technical field of tunnel engineering, in particular to a shield wall rear grouting slurry diffusion visualization test device. Background Art

[0002] The shield method has gradually become a common construction method for urban tunnel construction due to its advantages such as small construction disturbance and high safety. During the shield construction process, the shield shell diameter is larger than the outer diameter of the lining, and the adverse effects such as over-excavation cause the lining to escape from the shield tail and form gaps of varying widths between the lining and the stratum, which is called the shield tail gap.

[0003] In order to control the stability of the surrounding soil, prevent large deformation of the stratum, enhance the anti-seepage capacity of the stratum, and effectively inhibit the floating of the lining, the shield tail gap is often filled with the back-wall grouting technology. However, due to the complex and changeable stratum properties, the grouting parameters have strong uncertainty and the diversity of slurry materials, resulting in unclear diffusion law of slurry in the stratum. In the construction stage, there is a lack of effective guidance for the technical parameters and material selection of the shield wall back-grouting, which to a certain extent hinders the development of theoretical research on the shield wall back-grouting. Therefore, it is necessary to design a shield wall back-grouting slurry diffusion visualization test device. Utility Model Content

[0004] In view of the above problems, the purpose of the utility model is to provide a shield wall rear grouting slurry diffusion visualization test device.

[0005] In order to achieve the above purpose, the utility model adopts the following technical solutions:

[0006] A visualization test device for grouting slurry diffusion behind a shield wall comprises a grouting system and a grouting receiving device, wherein the grouting receiving device comprises a transparent tube; a linear motion positioning mechanism and a slurry inlet are arranged at the front end of the transparent tube; a clamping mechanism and a slurry outlet are arranged at the rear end of the transparent tube; the grouting system is connected to the slurry inlet via a connecting pipeline; the linear motion positioning mechanism comprises a positioning piston, which can close the transparent tube, and the positioning piston does not block the slurry inlet after being retracted and seated on the bottom; the clamping mechanism comprises a slurry-permeable piston, and the slurry can pass through the slurry-permeable piston.

[0007] Furthermore, the linear motion positioning mechanism includes a front end cover, a first support rod, and a positioning piston;

[0008] Specifically, the front end cover is arranged at the front end of the transparent tube, the first support rod passes through the center of the front end cover, the first support rod is threadedly connected to the front end cover, and the part of the first support rod extending into the transparent tube is connected to the positioning piston;

[0009] Specifically, the slurry inlet is arranged on the front end side wall of the transparent tube;

[0010] Specifically, the thickness of the positioning piston is equal to the distance between the slurry inlet and the front end of the transparent tube.

[0011] Furthermore, the clamping mechanism includes a rear end cover, a second support rod, and a slurry-permeable piston;

[0012] Specifically, the rear end cover is arranged at the rear end of the transparent tube, the second support rod passes through the center of the rear end cover, the second support rod is threadedly connected to the rear end cover, and the portion of the second support rod extending into the transparent tube is connected to the pulp-permeable piston;

[0013] Specifically, the slurry outlet is arranged on the rear end side wall of the transparent tube, and the slurry outlet is between the slurry permeable piston and the rear end cover;

[0014] Specifically, the slurry-permeable piston is a piston provided with an axial through hole, and the slurry can pass through the slurry-permeable piston.

[0015] Furthermore, the transparent tube is a transparent multi-section spliced ​​tube, and the transparent multi-section spliced ​​tube is formed by connecting transparent acrylic round tubes;

[0016] Specifically, two adjacent sections of transparent acrylic round tubes are connected by flanges, a circle of sealing gaskets is arranged between the flanges, and a distance scale is attached to the outside of the transparent acrylic round tubes.

[0017] Furthermore, the grouting system includes an air compressor and an electric stirring stainless steel pressure slurry storage barrel;

[0018] Specifically, the electric stirring stainless steel pressure slurry storage barrel is provided with an air inlet at the top or the upper end of the side wall, and the air inlet is connected to the air compressor through an air pipeline;

[0019] Specifically, a discharge port is provided at the bottom of the electric stirring stainless steel pressure slurry storage barrel, and a third slurry stop valve is provided at the discharge port; the discharge port is connected with the slurry inlet through a connecting pipeline.

[0020] Further, it also includes a data acquisition system;

[0021] Specifically, the data acquisition system includes a flow sensor, a pressure sensor, a micro pore water pressure gauge, a micro earth pressure gauge, and a data acquisition instrument;

[0022] Specifically, the flow sensor and the pressure sensor are arranged on the connecting pipeline;

[0023] Specifically, the micro pore water pressure gauge and the micro soil pressure gauge are alternately arranged in the transparent tube, and the micro pore water pressure gauge and the micro soil pressure gauge are connected by a lead wire, and the lead wire passes through the transparent tube and is connected to a data acquisition instrument.

[0024] Compared with the prior art, the utility model has the following beneficial effects:

[0025] 1. The utility model can simulate the filling process of slurry in the gap at the shield tail, realize the compaction of sand and the adjustment of the gap at the shield tail through the linear motion positioning mechanism and the compaction mechanism, the positioning piston provides support for the compaction process of sand and forms the gap at the shield tail, the slurry-permeable piston allows the slurry to pass through, and cooperates with the transparent multi-section splicing tube so that the experimenter can observe the diffusion process.

[0026] 2. The injection receiving device of the utility model is connected by multiple sections of transparent acrylic circular tubes. Before the test begins, a distance ruler is attached to the outside of the circular tube to facilitate observation of the slurry diffusion distance and calculation of the front diffusion rate. At the same time, after the grouting is completed, the circular tubes of the injection receiving device are disassembled for maintenance. Each section of the circular tube can be connected to the end cover separately to test the permeability coefficient of the stone body and evaluate the anti-seepage performance of the formation.

[0027] 3. The utility model adopts an electric stirring stainless steel pressure slurry storage barrel, which can prevent the slurry from stratification and segregation during the test, ensure the slurry is uniform and thus improve the accuracy of the test results.

[0028] 4. The utility model buries a micro pore water pressure gauge and an earth pressure gauge during the layered filling process of the injected sand and soil, and connects them through a lead wire, which passes through a grout-permeable piston and a sealed cable joint of a wire hole and is connected to a data acquisition instrument, thereby improving the overall sealing of the device and enabling continuous data collection and recording. BRIEF DESCRIPTION OF THE DRAWINGS

[0029] Figure 1 It is a structural schematic diagram of a shield wall back-injection slurry diffusion visualization test device of the utility model;

[0030] Figure 2 It is a structural schematic diagram of the electric stirring stainless steel pressure slurry storage barrel in the utility model;

[0031] Figure 3 It is a structural schematic diagram of the injection receiving device in the utility model.

[0032] In the figure: 1. Air compressor;

[0033] 2. Electric stirring stainless steel pressure slurry storage barrel; 2-1. Feeding funnel; 2-2. Air inlet; 2-3. Discharge port; 2-4. Electric stirrer;

[0034] 3. Pressure sensor; 4. Flow sensor;

[0035] 5. Injection receiving device; 5-1. Transparent multi-section splicing pipe; 5-2. Flange; 5-3. Front end cover; 5-4. First support rod; 5-5. Second support rod; 5-6. Slurry inlet; 5-7. Slurry outlet; 5-8. Rear end cover; 5-9. Positioning piston; 5-10. Slurry penetrating piston;

[0036] 6. Data acquisition instrument; 7. Connecting pipeline; 8. Micro pore water pressure gauge; 9. Micro soil pressure gauge. DETAILED DESCRIPTION

[0037] The following will be combined with the drawings in the embodiments of the utility model to clearly and completely describe the technical solutions in the embodiments of the utility model. Obviously, the described embodiments are only part of the embodiments of the utility model, not all of the embodiments. Based on the embodiments in the utility model, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the utility model. Example

[0038] See also Figures 1 to 3 The utility model provides a visualization test device for grouting slurry diffusion behind a shield wall, comprising a grouting system and a grouting receiving device 5. The grouting receiving device 5 comprises a transparent multi-section spliced ​​tube 5-1. The front end of the transparent multi-section spliced ​​tube 5-1 is provided with a linear motion positioning mechanism and a slurry inlet 5-6. The rear end of the transparent multi-section spliced ​​tube 5-1 is provided with a clamping mechanism and a slurry outlet 5-7. The grouting system is connected to the slurry inlet 5-6 via a connecting pipe 7.

[0039] Furthermore, the linear motion positioning mechanism includes a front end cover 5-3, a first support rod 5-4, and a positioning piston 5-9. The slurry inlet 5-6 is arranged on the front end side wall of the transparent multi-section spliced ​​tube 5-1. The front end cover 5-3 is arranged at the front end port of the transparent multi-section spliced ​​tube 5-1. The first support rod 5-4 passes through the center of the front end cover 5-3. The first support rod 5-4 is threadedly connected to the front end cover 5-3. The part of the first support rod 5-4 extending into the transparent multi-section spliced ​​tube 5-1 is connected to the positioning piston 5-9. The positioning piston 5-9 can close the transparent multi-section spliced ​​tube 5-1. The thickness of the positioning piston 5-9 is less than or equal to the distance between the slurry inlet 5-6 and the front end port of the transparent multi-section spliced ​​tube 5-1, so that the positioning piston 5-9 cannot block the slurry inlet 5-6 after sitting on the bottom. The positioning piston 5-9 is used to adjust the shield tail gap width of the experimental design.

[0040] Preferably, the thickness of the positioning piston 5-9 is equal to the distance between the slurry inlet 5-6 and the front end of the transparent multi-section spliced ​​tube 5-1, so that the slurry can directly diffuse into the sand after entering the transparent multi-section spliced ​​tube 5-1.

[0041] Furthermore, the clamping mechanism includes a rear end cover 5-8, a second support rod 5-5, and a slurry-permeable piston 5-10, the slurry outlet 5-7 is arranged on the rear end side wall of the transparent multi-section spliced ​​tube 5-1, the rear end cover 5-8 is arranged on the rear end port of the transparent multi-section spliced ​​tube 5-1, the second support rod 5-5 passes through the center of the rear end cover 5-8, the second support rod 5-5 is threadedly connected to the rear end cover 5-8, the part of the second support rod 5-5 extending into the transparent multi-section spliced ​​tube 5-1 is connected to the slurry-permeable piston 5-10, the slurry can pass through the slurry-permeable piston 5-10, the slurry outlet 5-7 is between the slurry-permeable piston 5-10 and the rear end cover, and the slurry-permeable piston 5-10 compacts the injected sand by rotating the second support rod 5-5.

[0042] Among them, the slurry-permeable piston 5-10 is a piston provided with an axial through hole, and the slurry can pass through the slurry-permeable piston 5-10.

[0043] The slurry inlet 5-6 is provided with a first slurry stop valve, the slurry outlet 5-7 is provided with a second slurry stop valve, and two slurry inlets 5-6 are arranged opposite to each other on the transparent multi-section splicing tube 5-1, one for injection and the other for front slurry discharge.

[0044] Among them, the transparent multi-section spliced ​​tube 5-1 is connected by transparent acrylic round tubes, and two adjacent sections of the round tubes are connected by flanges 5-2. There is a circle of sealing gaskets between the flanges 5-2. The transparent multi-section spliced ​​tube 5-1 is attached with a distance scale on the outside to facilitate the measurement of the slurry diffusion distance and the front diffusion rate. The transparent multi-section spliced ​​tube 5-1 is convenient for layered filling of sand and soil.

[0045] The injected sand in the transparent multi-section spliced ​​tube 5-1 is the original soil collected at the shield construction site. After measuring its basic physical properties such as particle size distribution, density, permeability coefficient, water content, porosity, etc., it is filled and compacted in layers to simulate the stratum characteristics of shield construction.

[0046] Furthermore, the grouting system includes an air compressor 1 and an electric stirring stainless steel pressure slurry storage barrel 2, the top of the electric stirring stainless steel pressure slurry storage barrel 2 is provided with a feed funnel 2-1 and an electric stirrer 2-4, the top or the upper end of the side wall of the electric stirring stainless steel pressure slurry storage barrel 2 is provided with an air inlet 2-2, the bottom of the electric stirring stainless steel pressure slurry storage barrel 2 is provided with a discharge port 2-3, the discharge port 2-3 is provided with a third slurry stop valve, the air inlet 2-2 is connected to the air compressor 1 through an air pipeline, and the discharge port 2-3 is connected to the slurry inlet 5-6 of the injection receiving device 5 through a connecting pipeline 7.

[0047] Among them, the newly mixed slurry is poured into the electric stirring stainless steel pressure slurry storage barrel 2 through the feed funnel 2-1, and then the electric mixer 2-4 is turned on to avoid slurry stratification and segregation during the test. The air compressor 1 continuously pumps compressed air into the electric stirring stainless steel pressure slurry storage barrel 2, and the compressed air provides power for slurry injection.

[0048] It should be noted that the air compressor 1, the electric mixers 2-4, and the valves themselves are existing technologies and can be purchased from the market, which is clear to those skilled in the art. Example

[0049] Based on Example 1, a data acquisition system is set up.

[0050] The data acquisition system includes a flow sensor 4 , a pressure sensor 3 , a micro pore water pressure gauge 8 , a micro soil pressure gauge 9 , and a data acquisition instrument 6 .

[0051] The flow sensor 4 and the pressure sensor 3 are arranged on the connecting pipeline 7 to monitor the injection flow and pressure. The flow sensor 4 and the pressure sensor 3 are connected to the data acquisition instrument 6 by wire or wirelessly.

[0052] The micro pore water pressure gauge 8 and the micro soil pressure gauge 9 are arranged alternately in the transparent multi-section splicing tube 5-1, with an interval of 5-10 cm. The micro pore water pressure gauge 8 and the micro soil pressure gauge 9 are connected by a lead wire. The rear end side wall of the transparent multi-section splicing tube 5-1 is provided with a wire hole. After the lead wire passes through the grouting piston 5-10 and the wire hole, it is connected to the data acquisition instrument 6.

[0053] Preferably, the cable hole is provided with a sealed cable joint to improve the sealing performance of the injection receiving device 5 .

[0054] Preferably, the micro pore water pressure gauge 8 and the micro soil pressure gauge 9 are spaced 10 cm apart.

[0055] It should be noted that the flow sensor 4, pressure sensor 3, micro pore water pressure gauge 8, micro soil pressure gauge 9, and data acquisition instrument 6 are existing technologies and can be purchased from the market, which is clear to those skilled in the art. Example

[0056] Based on Example 2, this example provides a method for using a shield wall back-grouting slurry diffusion visualization test device, which specifically includes the following steps:

[0057] S1. Insert the first support rod 5-4 into the front end cover 5-3, plug and fix the positioning piston 5-9 with the first support rod 5-4, connect the internal thread of the front end cover 5-3 with the external thread of the front end of the first section of transparent acrylic round tube, and adjust the distance between the positioning piston 5-9 and the front end cover 5-3 through the first support rod 5-4. This distance is the shield tail gap width designed for the test;

[0058] S2, insert the lead wire into the transition section transparent acrylic tube and the last section transparent acrylic tube, fill the first section transparent acrylic tube with the original soil collected at the shield construction site, fill the first section transparent acrylic tube, place a sealing gasket on the flange 5-2, connect the transition section transparent acrylic tube, and continue to fill the soil until the last section transparent acrylic tube;

[0059] When filling the soil, the micro pore water pressure gauge 8 and the micro soil pressure gauge 9 are buried alternately;

[0060] S3, insert the second support rod 5-5 into the rear end cover 5-8, plug and fix the slurry-permeable piston 5-10 with the second support rod 5-5, pass the lead wire through the slurry-permeable piston 5-10 and the wire hole, connect the internal thread of the rear end cover 5-8 with the external thread of the last section of the transparent acrylic round tube, and press the sand by adjusting the second support rod 5-5;

[0061] S4, connect the air compressor 1, the electric stirring stainless steel pressure slurry storage barrel 2, the connecting pipeline 7, and the injection receiving device 5 in sequence;

[0062] Connect the pressure sensor 3, flow sensor 4, micro pore water pressure gauge 8, micro soil pressure gauge 9 to the data acquisition instrument 6;

[0063] S5, adjust the positioning piston 5-9 through the first support rod 5-4, so that the positioning piston 5-9 contacts and bottoms with the front end cover 5-3, and the shield tail gap becomes the distance between the front end surface of the compacted sand and the rear end surface of the positioning piston 5-9;

[0064] Add slurry to the electric stirring stainless steel pressure slurry storage barrel 2, start the electric stirrer 2-4, open the first slurry stop valve connected to the connecting pipeline 7, open the second slurry stop valve, open the third slurry stop valve, and start the air compressor 1;

[0065] The slurry is pressed into the gap at the shield tail, where it diffuses into the sand. The transparent acrylic tube allows the tester to observe the diffusion. The pressure sensor 3, flow sensor 4, micro pore water pressure gauge 8, and micro soil pressure gauge 9 record various data during the injection and diffusion process, which is convenient for the tester to analyze the test results after the test.

[0066] S6. After the test, turn off the air compressor 1, the electric mixer 2, and the first slurry stop valve with connecting pipeline 7, open the first slurry stop valve of the air connection, drain the slurry, then close all valves, dismantle the device for cleaning.

[0067] All components and connection methods of components not discussed in this application belong to the known technologies in this technical field and can be directly applied without further explanation.

[0068] In the present invention, the term "plurality" means two or more than two, unless otherwise clearly defined. The terms "install", "connect", "connect", "fix" and the like should be understood in a broad sense. For example, "connect" can be a fixed connection, a detachable connection, or an integral connection; "connected" can be a direct connection or an indirect connection through an intermediate medium. For those of ordinary skill in the art, the specific meanings of the above terms in the present invention can be understood according to the specific circumstances.

[0069] In the description of the present invention, it is necessary to understand that the directions or positional relationships indicated by terms such as "up", "down", "left", "right", "front" and "back" are based on the directions or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or unit referred to must have a specific direction, be constructed and operated in a specific orientation, and therefore, cannot be understood as a limitation on the present invention.

[0070] In the description of this specification, the description of the terms "one embodiment", "some embodiments", "specific embodiments", etc. means that the specific features, structures, materials or characteristics described in conjunction with the embodiment or example are included in at least one embodiment or example of the utility model. In this specification, the schematic representation of the above terms does not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials or characteristics described can be combined in any one or more embodiments or examples in a suitable manner.

[0071] The above description is only the preferred embodiment of the utility model, and is not intended to limit the utility model. For those skilled in the art, the utility model can have various modifications and changes. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the utility model shall be included in the protection scope of the utility model.

Claims

1. A shield wall rear grouting slurry diffusion visualization test device, including a grouting system and a grouting receiving device, characterized in that: The injection receiving device comprises a transparent tube; The front end of the transparent tube is provided with a linear motion positioning mechanism and a slurry inlet; The rear end of the transparent tube is provided with a pressing mechanism and a slurry outlet; The grouting system is connected to the slurry inlet via a connecting pipeline; The linear motion positioning mechanism includes a positioning piston, the positioning piston can close the transparent tube, and the positioning piston does not block the pulp inlet after being retracted and seated on the bottom; The pressing mechanism comprises a slurry-permeable piston, and the slurry can pass through the slurry-permeable piston.

2. A shield wall post-grouting slurry diffusion visualization test device according to claim 1, characterized in that: The linear motion positioning mechanism comprises a front end cover, a first support rod, and a positioning piston; The front end cover is arranged at the front end of the transparent tube, the first support rod passes through the center of the front end cover, the first support rod is threadedly connected to the front end cover, and the part of the first support rod extending into the transparent tube is connected to the positioning piston; The slurry inlet is arranged on the front end side wall of the transparent tube; The thickness of the positioning piston is equal to the distance between the slurry inlet and the front end of the transparent tube.

3. A shield wall post-grouting slurry diffusion visualization test device according to claim 1, characterized in that: The clamping mechanism includes a rear end cover, a second support rod, and a slurry-permeable piston; The rear end cover is arranged at the rear end of the transparent tube, the second support rod passes through the center of the rear end cover, the second support rod is threadedly connected to the rear end cover, and the portion of the second support rod extending into the transparent tube is connected to the pulp-permeable piston; The slurry outlet is arranged on the rear end side wall of the transparent tube, and the slurry outlet is between the slurry permeable piston and the rear end cover; The slurry-permeable piston is a piston provided with an axial through hole, and the slurry can pass through the slurry-permeable piston.

4. A shield wall post-grouting slurry diffusion visualization test device according to any one of claims 1 to 3, characterized in that: The transparent tube is a transparent multi-section spliced ​​tube, which is formed by connecting transparent acrylic round tubes; Two adjacent sections of transparent acrylic round tubes are connected by flanges, a circle of sealing gasket is arranged between the flanges, and a distance scale is attached to the outside of the transparent acrylic round tube.

5. The shield wall post-grouting slurry diffusion visualization test device according to claim 1 is characterized in that: The grouting system includes an air compressor and an electric stirring stainless steel pressure slurry storage barrel; The electric stirring stainless steel pressure slurry storage barrel is provided with an air inlet at the top or the upper end of the side wall, and the air inlet is connected to the air compressor through an air pipeline; The bottom of the electric stirring stainless steel pressure slurry storage barrel is provided with a discharge port, and the discharge port is provided with a third slurry stop valve; the discharge port is connected with the slurry inlet through a connecting pipeline.

6. A shield wall post-grouting slurry diffusion visualization test device according to claim 1, characterized in that: It also includes a data acquisition system; The data acquisition system includes a flow sensor, a pressure sensor, a micro pore water pressure gauge, a micro earth pressure gauge, and a data acquisition instrument; The flow sensor and the pressure sensor are arranged on the connecting pipeline; The micro pore water pressure gauge and the micro soil pressure gauge are alternately arranged in the transparent tube, and the micro pore water pressure gauge and the micro soil pressure gauge are connected by a lead wire, and the lead wire passes through the transparent tube and is connected to a data acquisition instrument.

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