A material slurry stopping performance testing device and method

Abstract

The present invention discloses a material grouting performance testing device and method, including a fixing mechanism, a grouting pressurizing mechanism and a data acquisition mechanism, wherein the fixing mechanism includes an upper plate, a lower plate and bolts; the grouting pressurizing mechanism includes a grouting pipe and a pressure test pump; the data acquisition mechanism includes a pressure gauge, a pressure gauge connecting pipe, a digital pressure controller and a pressure sensor transmitter; a central through hole is provided at the center of the upper plate, the upper surface of the central through hole is fixedly connected to the pressure gauge connecting pipe, and the pressure gauge connecting pipe is connected to the pressure gauge; the upper plate also includes an inner ring through hole with a thread arranged circumferentially near the center of the circle, and a first outer ring through hole with a thread arranged circumferentially away from the center of the circle. The material grouting performance testing method provided by the present invention can test the relationship between different slurry water-cement ratios, contact pressure and grouting pressure under grouting pressure, so as to provide basic data support for the process design of grouting materials.

Description

Technical Field

[0001] The invention belongs to the technical field of material slurry stopping performance testing, and in particular relates to a material slurry stopping performance testing device and method. Background Art

[0002] Bolt support technology is an important part of the initial support of mining tunnels. It has the functions of suspension, span reduction, composite beam, extrusion reinforcement, etc. It can effectively improve the self-bearing capacity of the surrounding rock and is a key link to ensure the safety and quality of the tunnel. The hollow grouting anchor is mainly composed of a hollow anchor body, an expansion shell anchor, a pad, a grouting plug, a nut and other parts. During on-site construction, the slurry enters the bottom of the borehole along the hollow anchor body, and gradually fills the annular area between the rod body and the hole wall from the bottom of the hole to the hole mouth. When the slurry reaches the grouting plug position, the grouting plug is squeezed and deformed to seal the borehole. Under the action of grouting pressure, the slurry infiltrates along the surrounding rock cracks to form a grouting tree system, which ensures the grouting anchoring effect and avoids the formation of grouting cavities, thereby achieving the improvement of the tunnel surrounding rock and improving the effect of bolt reinforcement. It can be seen from the action mechanism of the hollow grouting anchor that the grouting quality is the main means to ensure its anchoring effect and durability. Grouting anchors are mainly fixed with expansion shell anchors and pads to ensure that the rod is centered in the anchor hole. The stop plug maintains pressure during the grouting process under the constraint of the pad to achieve the grouting effect. Therefore, as a key link in ensuring the quality of grouting during the grouting process, the mechanical properties, basic structure, and grouting performance of the material of the stop plug play an important role. Therefore, in actual engineering applications, it is very necessary to continuously optimize the relevant properties of the material to improve the grouting effect and ensure safe grouting of the tunnel.

[0003] Grout-stopping materials are widely used, such as natural rubber, EPDM rubber, etc. However, there is currently a lack of necessary testing methods and devices for the grout-stopping performance of the material itself, resulting in a lack of basic data when designing grout-stopping products, which in turn causes product quality problems and reduces the anchoring effect of the anchor bolt.

[0004] In addition, pressure grouting processes such as advance grouting, curtain grouting, and splitting grouting generally require the installation of a grouting stop ring, which mainly relies on the grouting stop ring (rubber material) to squeeze and fit tightly against the surrounding rock to achieve the grouting function. Therefore, performance testing of the grouting stop material is very necessary.

[0005] At present, there are relatively few testing methods and devices for the grouting performance of grouting plug materials. In order to facilitate the development of new grouting plug materials, timely feedback of material defects, and evaluation of the grouting effect of grouting plugs, a material grouting performance testing device and method are specially developed. This invention can be used to clarify the grouting performance of the material contact surface, that is, the relationship between rubber materials, slurry water-cement ratio, contact pressure and grouting pressure. It can provide basic data for the design of anchor grouting plugs, grouting pipes and other grouting systems. It can also be used as a standard for testing the grouting performance of grouting materials, and provide a basis for the formulation of grouting material standards. It has broad application prospects. Summary of the invention

[0006] In view of the shortcomings of the prior art, the purpose of the present invention is to provide a device and method for testing the slurry-stopping performance of the material contact surface, mainly to clarify the slurry-stopping performance of the material contact surface, that is, the relationship between the slurry water-cement ratio, contact pressure and slurry-stopping pressure, so as to provide basic data support for the process design of slurry-stopping materials.

[0007] To achieve the above object, the present invention provides the following technical solutions:

[0008] A device for testing the grouting performance of a material, comprising a fixing mechanism, a grouting pressurizing mechanism and a data acquisition mechanism, wherein the fixing mechanism comprises an upper plate, a lower plate and bolts; the grouting pressurizing mechanism comprises a grouting pipe and a pressure test pump; the data acquisition mechanism comprises a pressure gauge, a pressure gauge connecting pipe, a digital pressure controller and a pressure sensor transmitter; a central through hole is provided at the center of the upper plate, the upper surface of the central through hole is fixedly connected to the pressure gauge connecting pipe, the pressure gauge connecting pipe is connected to the pressure gauge, and the digital pressure controller is connected to the pressure sensor transmitter; the upper plate also comprises an inner ring through hole with a thread arranged circumferentially near the center of the circle, and a first outer ring through hole with a thread arranged circumferentially away from the center of the circle.

[0009] Preferably, the lower plate is provided with a second outer ring through hole with a thread, and the position, size and number of the second outer ring through hole are the same as those of the first outer ring through hole; a circular ring groove with an inverted trapezoidal cross-section is circumferentially arranged on the lower plate, and the circular ring groove is located directly below the inner ring through hole.

[0010] Preferably, the lower plate is provided with a grouting hole at the center of the circle, the lower surface of the grouting hole is fixedly connected to the grouting pipe, and the grouting pipe is connected to the pressure test pump.

[0011] Preferably, the number of the inner ring through holes is 3-6, and the number of the first outer ring through holes is 10-16.

[0012] Preferably, the inner diameter of the pressure gauge connecting pipe is 14-20 mm and the height is 8-12 cm.

[0013] Preferably, the diameter of the first outer ring through hole is 14-20 mm; the diameter of the central through hole is 14-20 mm; the size of the inner ring through hole is the same as that of the pressure sensor transmitter; and the diameter of the grouting hole is 8-14 mm.

[0014] Preferably, the number of the pressure sensor transmitters is 3-6, and the number of the digital pressure controllers is 3-6.

[0015] Preferably, the pressure sensor transmitter is provided with a probe.

[0016] The present invention also protects a method for testing the grout-stopping performance of a material using the device, comprising the following steps:

[0017] Step 1: Clean the groove of the annular body of the lower plate of the device and place the stop slurry material sample;

[0018] Step 2: Install the pressure sensor transmitter in the inner circle through hole of the upper plate of the device, ensuring that the probe on the pressure sensor transmitter is flush with the lower surface of the upper plate;

[0019] Step 3: Align the first outer ring through hole and the second outer ring through hole of the upper and lower plates of the device, and position the upper and lower plates of the device by bolts, without tightening the bolts temporarily;

[0020] Step 4: Assemble the digital pressure controller and connect the digital pressure controller to the pressure sensor transmitter;

[0021] Step 5: Use a wrench to adjust the torque of the bolt diagonally to position the stop material sample;

[0022] Step six, prepare cement slurry according to a certain slurry water-cement ratio, inject cement slurry into the device through the grouting pipe by means of a pressure test pump, load it step by step according to a certain grouting pressure, read and record the readings of the pressure gauge and the digital pressure controller respectively after reaching the set grouting pressure, and maintain the pressure for a certain time, and finally judge the grouting performance of the grouting material by the ratio of the reading of the digital pressure controller to the reading of the pressure gauge.

[0023] Compared with the prior art, the present invention has the following beneficial effects:

[0024] The present invention provides a material grouting performance testing device and method, which can test the relationship between different slurry water-cement ratios, contact pressure and grouting pressure under grouting pressure, and develops a material contact surface grouting performance testing device with high precision and strong applicability; proposes a material contact surface grouting performance testing method, which can realize the material contact surface grouting performance test, and obtain the relationship between different slurry water-cement ratios, contact pressure and grouting pressure when the material is in extrusion contact with the surrounding rock wall. The present invention can be used as a standard for grouting performance testing of grouting materials, and provide a basis for the formulation of grouting material standards. BRIEF DESCRIPTION OF THE DRAWINGS

[0025] Figure 1 A device for testing the grout-stopping performance of the material described in Example 1 of the present invention;

[0026] Figure 2 It is a top view of the upper plate of the grout-stopping performance testing device of the material of the present invention;

[0027] Figure 3 It is a front view of the lower plate of the grout-stopping performance testing device of the material of the present invention;

[0028] Figure 4 It is a top view of the lower plate of the device for testing the grout-stopping performance of the material described in the present invention.

[0029] Among them, 1. upper plate; 2. lower plate; 3. pressure gauge; 4. pressure gauge connecting pipe; 5. digital pressure controller; 6. pressure sensor transmitter; 7. grouting pipe; 8. bolts; 9. pressure test pump; 10. center through hole; 11. inner ring through hole; 12. first outer ring through hole; 13. second outer ring through hole; 14. annular ring groove. DETAILED DESCRIPTION

[0030] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0031] Example 1

[0032] A device for testing the grouting performance of a material, comprising a fixing mechanism, a grouting pressurizing mechanism and a data acquisition mechanism, wherein the fixing mechanism comprises an upper plate 1, a lower plate 2 and bolts 8; the grouting pressurizing mechanism comprises a grouting pipe 7 and a pressure test pump 9; the data acquisition mechanism comprises a pressure gauge 3, a pressure gauge connecting pipe 4, a digital pressure controller 5 and a pressure sensor transmitter 6; a central through hole 10 with a diameter of 16 mm is provided at the center of the upper plate 1, and the upper surface of the central through hole 10 is fixedly connected to the pressure gauge connecting pipe 4, the inner diameter of the pressure gauge connecting pipe 4 is 16 mm and the height is 10 cm; the pressure gauge connecting pipe 4 is connected to the pressure gauge 3, and the digital pressure controller 5 is connected to the pressure sensor transmitter 6; the upper plate 1 also comprises four equidistant inner ring through holes 11 with threads arranged circumferentially near the center of the circle, and 12 equidistant first outer ring through holes 12 with threads having a diameter of 16 mm are arranged circumferentially away from the center of the circle.

[0033] In this embodiment, a second outer ring through hole 13 with a thread is provided on the lower plate 2, and the position, size and number of the second outer ring through hole 13 and the first outer ring through hole 12 are the same; a circular ring groove 14 with an inverted trapezoidal cross section is circumferentially arranged on the lower plate 2, and the circular ring groove 14 is located directly below the inner ring through hole 11.

[0034] In this embodiment, the lower plate 2 is provided with a grouting hole with a diameter of 8 mm at the center of the circle, the lower surface of the grouting hole is fixedly connected to the grouting pipe 7, and the grouting pipe 7 is connected to the pressure test pump 9.

[0035] In this embodiment, the number of the pressure sensor transmitters 6 is four, and the number of the digital pressure controllers 5 is four.

[0036] In this embodiment, the pressure sensor transmitter 6 is provided with a probe.

[0037] A method for testing the grout-stopping performance of a material using the device described in Example 1 comprises the following steps:

[0038] Step 1: clean the groove 14 of the lower plate annular body of the device and place a sample of the slurry-stopping material;

[0039] Step 2: Install the pressure sensor transmitter 6 in the inner circle through hole 11 of the upper plate of the device, ensuring that the probe on the pressure sensor transmitter 6 is flush with the lower surface of the upper plate 1;

[0040] Step 3: Align the first outer ring through hole 12 and the second outer ring through hole 13 of the upper and lower plates of the device, and position the upper and lower plates of the device by means of bolts, without tightening the bolts temporarily;

[0041] Step 4: Assemble the digital pressure controller 5 and connect the digital pressure controller 5 to the pressure sensor transmitter 6;

[0042] Step 5: Use a wrench to adjust the torque of the bolt diagonally to position the stop material sample;

[0043] Step six, inject cement slurry into the device through the grouting pipe 7 by means of the pressure test pump 9, load the grouting pressure step by step, maintain the pressure after reaching the set grouting pressure, read and record the readings of the pressure gauge 3 and the digital pressure controller 5 respectively after the pressure stabilizes, and finally judge the grouting performance of the grouting material by the ratio of the reading of the digital pressure controller 5 to the reading of the pressure gauge 3.

[0044] The principle of the device for testing the grouting performance of the material is as follows: the device positions the grouting material sample through the upper plate 1 and the lower plate 2, and sets a pressure sensor transmitter 6 in the inner circle through hole 11 of the upper plate 1 to monitor the pressure to which the grouting material is subjected during the grouting process. At the same time, the grouting pressure of the slurry in the device is monitored by the pressure gauge 3. Finally, the relationship between different slurry water-cement ratios, contact pressure and grouting pressure under a specific grouting pressure can be tested. That is, the grouting performance of the grouting material is judged by the ratio of the reading of the digital pressure controller 5 to the reading of the pressure gauge 3. The smaller the ratio, the better the grouting performance of the grouting material; the larger the ratio, the worse the grouting performance of the grouting material.

[0045] Although embodiments of the present invention have been shown and described, it will be appreciated by those skilled in the art that various changes, modifications, substitutions and variations may be made to the embodiments without departing from the principles and spirit of the present invention, and that the scope of the present invention is defined by the appended claims and their equivalents.

Claims

1. A device for testing the slurry stopping performance of a material, characterized in that: The invention comprises a fixing mechanism, a grouting pressurizing mechanism and a data acquisition mechanism, wherein the fixing mechanism comprises an upper plate (1), a lower plate (2) and bolts (8); the grouting pressurizing mechanism comprises a grouting pipe (7) and a pressure test pump (9); the data acquisition mechanism comprises a pressure gauge (3), a pressure gauge connecting pipe (4), a digital pressure controller (5) and a pressure sensor transmitter (6); a central through hole (10) is provided at the center of the upper plate (1), the upper surface of the central through hole (10) is fixedly connected to the pressure gauge connecting pipe (4), the pressure gauge connecting pipe (4) is connected to the pressure gauge (3), and the digital pressure controller (5) is connected to the pressure sensor transmitter (6); the upper plate (1) also comprises an inner ring through hole (11) with threads arranged in an annular direction near the center of the circle, and a first outer ring through hole (12) with threads arranged in an annular direction away from the center of the circle; The lower plate (2) is provided with a second outer ring through hole (13) with a thread, and the second outer ring through hole (13) and the first outer ring through hole (12) are identical in position, size and number; the lower plate (2) is provided with a circular ring groove (14) with an inverted trapezoidal cross section, and the circular ring groove (14) is located directly below the inner ring through hole (11); The lower plate (2) is provided with a grouting hole at the center of the circle, the lower surface of the grouting hole is fixedly connected to the grouting pipe (7), and the grouting pipe (7) is connected to the pressure test pump (9).

2. A material slurry stopping performance testing device according to claim 1, characterized in that: The number of the inner ring through holes (11) is 3-6, and the number of the first outer ring through holes (12) is 10-16.

3. The device for testing the grout stopping performance of a material according to claim 1, characterized in that: The inner diameter of the pressure gauge connecting pipe (4) is 14-20 mm and the height is 8-12 cm.

4. A material slurry stopping performance testing device according to claim 1, characterized in that: The diameter of the first outer ring through hole (12) is 14-20 mm; the diameter of the central through hole (10) is 14-20 mm; the size of the inner ring through hole (11) is the same as that of the pressure sensor transmitter (6); and the diameter of the grouting hole is 8-14 mm.

5. The device for testing the grout stopping performance of a material according to claim 1, characterized in that: The number of the pressure sensor transmitters (6) is 3-6, and the number of the digital pressure controllers (5) is 3-6.

6. A material grouting performance testing device according to claim 5, characterized in that: The pressure sensor transmitter (6) is provided with a probe.

7. A method for testing the grout-stopping performance of a material using the device according to any one of claims 1 to 6, characterized in that: The following steps are involved: Step 1: clean the groove (14) of the annular body of the lower plate of the device and place a sample of the slurry-stopping material thereon; Step 2: Install the pressure sensor transmitter (6) in the inner circle through hole (11) of the upper plate of the device, ensuring that the probe on the pressure sensor transmitter (6) is flush with the lower surface of the upper plate (1); Step 3: Align the first outer ring through hole (12) and the second outer ring through hole (13) of the upper and lower plates of the device, and position the upper and lower plates of the device by means of bolts, without tightening the bolts temporarily; Step 4: Assemble the digital pressure controller (5), and connect the digital pressure controller (5) to the pressure sensor transmitter (6); Step 5: Use a wrench to adjust the torque of the bolt diagonally to position the stop material sample; Step 6: Use the pressure test pump (9) to inject cement slurry into the device through the grouting pipe (7), and gradually load the grouting pressure. After reaching the set grouting pressure, maintain the pressure. After the pressure stabilizes, read the readings of the pressure gauge (3) and the digital pressure controller (5) and record them. Finally, judge the grouting performance of the grouting material by the ratio of the reading of the digital pressure controller (5) to the reading of the pressure gauge (3).

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