Real-time grouting device based on true three-direction three-rigidity pressure testing machine

Abstract

The invention provides a real-time grouting device based on a true three-way three-rigidity pressure testing machine, which comprises a pressure sealing box with a rectangular structure, the pressure sealing box is formed by splicing four sealing elements, each side wall of the pressure sealing box is provided with a rigid pressing plate, the rigid pressing plate comprises a connecting pipe, and the connecting pipe is provided with a plurality of clamping grooves. A pressing plate is fixed to the inner end of the connecting pipe, a grouting pipe is arranged in the connecting pipe, a grouting hole is formed in the pressing plate, and one end of the grouting pipe is connected with the grouting hole. The device can be carried on a three-way rigid loading true triaxial testing machine to carry out a real-time grouting test, meanwhile, according to the designed test method, complete reduction and simulation of the grouting reinforcement working condition in deep engineering can be achieved, loading and grouting can be completed at the same time through the pressure head, the requirement for real-time grouting reinforcement is met, and the test efficiency is improved. The real-time grouting reinforcement mechanism of the deeply-buried engineering rock mass under the true triaxial excavation stress path change can be studied, and a theoretical basis is provided for grouting engineering design.

Description

Technical Field

[0001] The invention belongs to the technical field of rock and soil experiments, and relates to a real-time grouting device based on a true three-way three-rigid pressure testing machine. Background Art

[0002] Geotechnical engineering often encounters some unfavorable geological bodies during the process. For example, tunnels may encounter faults and broken zones during excavation. Under the influence of excavation disturbance, these unfavorable geological surrounding rocks will undergo large deformations or even collapses, which will seriously affect the construction progress of the tunnel and endanger the safety of on-site construction personnel and equipment. Grouting reinforcement technology is an effective and convenient support method. Through advanced / delayed grouting in the surrounding rocks of unfavorable geological bodies, the solidified slurry will re-cement these broken and unstable surrounding rocks together, fill the cementation cracks, and prevent the cracks from further developing, thereby inhibiting the surrounding rock from cracking and deformation to the deep layer, thereby effectively controlling the stability of the surrounding rock. With the development of servo testing machine technology, true three-axis servo testing machines have appeared, realizing the reproduction of the true three-axis stress environment of deep engineering.

[0003] The patent with publication number CN210347401U provides various existing high-strength, pressure-resistant and wear-resistant rubber materials that are widely used in sealing devices under various extreme conditions. There are still some problems in using high-strength, pressure-resistant and wear-resistant rubber materials for sealing. The patent with publication number CN112014228B introduces the use of "two rigid and one flexible" loading method to load the surrounding rock, and then uses the pressure chamber sealed by the sealing strip to perform grouting permeability test, but the test process separates loading and grouting, which does not meet the needs of real-time grouting reinforcement. Summary of the invention

[0004] The purpose of the present invention is to provide a real-time grouting device based on a true three-way three-rigid pressure testing machine in view of the problems existing in the prior art.

[0005] To this end, the present invention adopts the following technical solutions: A real-time grouting device based on a true three-way three-rigid pressure testing machine comprises a pressure sealing box with a rectangular structure, the pressure sealing box is composed of four sealing parts spliced ​​together, each side wall of the pressure sealing box is provided with a rigid pressure head, the rigid pressure head comprises a connecting pipe, the side wall of the pressure sealing box is provided with a mounting hole corresponding to the connecting pipe box, the connecting pipe passes through the mounting hole, a pressing plate is fixed to the inner end of the connecting pipe, a grouting pipe is provided in the connecting pipe, a grouting hole is provided on the pressing plate, one end of the grouting pipe is connected to the grouting hole, and the other end passes through the side wall of the connecting pipe.

[0006] Furthermore, the pressure sealing box is a square structure.

[0007] Furthermore, the connecting pipe and the side wall of the pressure sealing box where the connecting pipe is located are in a vertical structure.

[0008] Furthermore, a flow guide portion is provided on the side away from the connecting pipe, and the grouting hole is located in the flow guide portion.

[0009] Furthermore, the guide portion includes a plurality of horizontal backflow grooves and vertical guide grooves.

[0010] Furthermore, the pressing plate and the connecting pipe are arranged perpendicular to each other.

[0011] Furthermore, a sealing ring is provided in the mounting hole.

[0012] Furthermore, a connecting plate which is arranged perpendicularly to the connecting pipe is fixed to the outer end of the connecting pipe, and a plurality of connecting holes are arranged on the connecting plate.

[0013] Furthermore, sealing strips are provided between the sealing elements.

[0014] The beneficial effects of the present invention are: a device that can be mounted on a three-way rigid loading true triaxial testing machine to conduct real-time grouting tests, and at the same time, according to the designed test method, it can achieve complete restoration and simulation of grouting reinforcement conditions in deep engineering projects, and loading and grouting can be completed simultaneously through the pressure head to meet the needs of real-time grouting reinforcement. The real-time grouting reinforcement mechanism of deeply buried engineering rock mass under the change of true triaxial excavation stress path can be studied, providing a theoretical basis for grouting engineering design. BRIEF DESCRIPTION OF THE DRAWINGS

[0015] Figure 1 It is a schematic diagram of the three-dimensional structure of the present invention; Figure 2 It is a schematic diagram of the three-dimensional structure of the sealing member of the present invention; Figure 3 It is a schematic front view of the structure of the rigid pressing head of the present invention; Figure 4 It is a schematic side view of the structure of the rigid pressing head of the present invention; In the figure, 1-pressure sealing box, 101-seal, 102-screw hole, 103-through hole, 104-bolt, 2-sealing strip, 3-rigid pressure head, 301-connecting pipe, 302-pressure plate, 303-connecting plate, 304-connecting hole, 4-mounting hole, 5-sealing ring, 6-grouting pipe, 7-grouting hole, 8-guide part, 801-horizontal guide groove, 802-vertical guide groove, 9-observation hole. DETAILED DESCRIPTION

[0016] The present invention is described in detail below in conjunction with the accompanying drawings: like Figure 1-4As shown, a real-time grouting device based on a true three-way three-rigid pressure testing machine includes a rectangular pressure sealing box 1, in which a rock sample is placed. The pressure sealing box 1 can prevent the rock sample from being damaged or cracked during the experiment, thereby causing damage to surrounding personnel or objects. At the same time, it can also prevent the slurry from flowing out of the rock sample during grouting, thereby causing damage to the testing machine. In this embodiment, the pressure sealing box 1 is a square structure, and the pressure sealing box 1 is composed of four sealing members 101, that is, a square box body is divided into four parts, and each part has the same shape. Specifically, screw holes 10 are arranged at the edges of the side walls of the four sealing members 101. 2, the side walls of adjacent sealing members 101 are provided with through holes 103 corresponding to the screw holes 102, and bolts 104 are provided in the screw holes, and the bolts 104 pass through the corresponding through holes 103, and the splicing of the sealing members 101 is completed by the bolts 104. In order to ensure the sealing, sealing strips 2 are provided between the sealing members 101, and each side wall of the pressure sealing box 1 is provided with a rigid pressure head 3. In this embodiment, a total of six rigid pressure heads 3 are provided, and the six rigid pressure heads 3 are grouped in pairs, corresponding to the X, Y and Z axes of the Cartesian rectangular coordinate system, respectively. The rigid pressure head 3 includes a connecting pipe 301, and the side wall of the pressure sealing box 1 is provided with a connecting pipe 30 1, the connecting pipe 301 and the side wall of the pressure sealing box 1 where the connecting pipe 301 is located are in a mutually perpendicular structure, the connecting pipe 301 passes through the mounting hole 4 and can move in the mounting hole 4, in addition, a sealing ring 5 is provided in the mounting hole 4, the connecting pipe 301 passes through the sealing ring 5, the inner end of the connecting pipe 301 is fixed with a pressing plate 302 which is mutually perpendicular to the connecting pipe 301, the pressing plate 302 is used to squeeze the rock sample, and the outer end of the connecting pipe 301 is fixed with a connecting plate 303 which is mutually perpendicular to the connecting pipe 301, and a plurality of connecting holes 304 are provided on the connecting plate 303, and the connecting plate 303 is used to connect the connecting pipe 301 to the connecting pipe 301. The connecting pipe 301 is connected to the relevant parts of the true three-way three-rigid pressure testing machine. A grouting pipe 6 is provided in the connecting pipe 301, and a grouting hole 7 is provided on the pressure plate 302. One end of the grouting pipe 6 is connected to the grouting hole 7, and the other end passes through the side wall of the connecting pipe 301. The grouting pipe 6 is used to grout into the grouting hole 7, and the rock sample is grouted through the grouting hole 7. Specifically, a guide part 8 is provided on the side of the pressure plate 302 away from the connecting pipe 301. The grouting hole 7 is located in the guide part 8. The guide part includes a plurality of horizontal guide grooves 801 and vertical guide grooves 802. The slurry can be evenly distributed on the surface of the rock sample through the horizontal guide grooves 801 and the vertical guide grooves 802.

[0017] In addition, in order to facilitate the use, the side wall of the pressure sealing box 1 is also provided with an observation hole 9 for observing the condition of the rock sample inside the sealing box 1 in the laboratory.

[0018] The use of the present invention is as follows: The connecting plates 303 of the six rigid pressure heads 3 are connected to the corresponding parts of the testing machine, and the six surfaces of the rock sample are respectively against the pressure plates 302 of the six rigid pressure heads 3. Then, the six rigid pressure heads 3 can be controlled by the testing machine to apply external forces to the rock sample in the three directions of the X, Y and Z axes to perform prestressed loading. The loading stress is 0.5MPa-1.0MPa. The purpose is to ensure that the rock sample is centered and will not loosen during the subsequent installation of the pressure chamber, thereby affecting the position of the rock sample. Then, the four sealing members 101 are spliced, and the six rigid pressure heads 3 are located at the corresponding positions during splicing. After the splicing is completed, the rock sample can be placed inside the pressure sealing box 1, and the rock sample can be stressed according to the designed stress path. The true triaxial test is carried out on the rock sample. After the rock sample breaks, that is, when the residual strength is reached, the loading on the rock sample is stopped. During the whole process, whether the rock sample is broken can be observed through the observation hole 9. After the loading is completed, the rock sample is grouted through two rigid pressure heads 3 in the Y-axis direction. After the grouting is completed, it can be observed through the observation hole 9. After the slurry is observed to solidify, the pressure sealing box 1 is removed. It is only necessary to keep loading the rock sample. After the hardened slurry injected into the rock sample reaches a certain curing age (3d, 7d and 28d), the test machine is controlled to end the load-keeping stress level of the true triaxial test machine on the rock sample according to the designed stress path, and the load on the rock sample is continued to be increased until the rock sample breaks and the residual strength is obtained, and the experiment is completed.

Claims

1. A real-time grouting device based on a true three-way three-rigid pressure testing machine, characterized in that: The invention comprises a pressure sealing box (1) having a rectangular structure, wherein the pressure sealing box (1) is composed of four sealing members (101) spliced ​​together, each side wall of the pressure sealing box (1) is provided with a rigid pressure head (3), the rigid pressure head (3) comprises a connecting pipe (301), the side wall of the pressure sealing box (1) is provided with a mounting hole (4) corresponding to the connecting pipe (301), the connecting pipe (301) passes through the mounting hole (4), a pressing plate (302) is fixed at the inner end of the connecting pipe (301), a grouting pipe (6) is provided in the connecting pipe (301), a grouting hole (7) is provided on the pressing plate (302), one end of the grouting pipe (6) is connected to the grouting hole (7), and the other end passes through the side wall of the connecting pipe (301).

2. A real-time grouting device based on a true three-dimensional three-rigid pressure testing machine according to claim 1, characterized in that: The pressure sealing box (1) is a square structure.

3. A real-time grouting device based on a true three-dimensional three-rigid pressure testing machine according to claim 1, characterized in that: The connecting pipe (301) and the side wall of the pressure sealing box (1) where the connecting pipe (301) is located are in a vertical structure.

4. A real-time grouting device based on a true three-dimensional three-rigid pressure testing machine according to claim 1, characterized in that: A flow guide portion (8) is provided on the side away from the connecting pipe (301), and the grouting hole (7) is located in the flow guide portion (8).

5. A real-time grouting device based on a true three-dimensional three-rigid pressure testing machine according to claim 4, characterized in that: The guide portion (8) comprises a plurality of transverse guide grooves (801) and vertical guide grooves (802).

6. A real-time grouting device based on a true three-dimensional three-rigid pressure testing machine according to claim 1, characterized in that: The pressing plate (302) and the connecting pipe (301) are arranged perpendicular to each other.

7. The real-time grouting device based on the true three-dimensional three-rigid pressure testing machine according to claim 1 is characterized in that: A sealing ring (5) is provided in the mounting hole (4).

8. The real-time grouting device based on the true three-dimensional three-rigid pressure testing machine according to claim 1 is characterized in that: A connecting plate (303) arranged perpendicularly to the connecting tube (301) is fixed to the outer end of the connecting tube (301), and a plurality of connecting holes (304) are provided on the connecting plate (303).

9. The real-time grouting device based on the true three-dimensional three-rigid pressure testing machine according to claim 1 is characterized in that: Sealing strips (2) are provided between the sealing elements (101).

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