A stress testing device for hollow infill bodies to prevent wire breakage

Abstract

This utility model relates to a hollow infill stress testing device with anti-breakage capability, belonging to the field of geostress testing equipment. It includes a glue storage cylinder containing adhesive within its inner cavity; a conical plunger connected to the front end of the storage cylinder; and an integrally molded epoxy resin cylinder at the rear end of the storage cylinder, with a glue outlet at one end near the epoxy resin cylinder. An anti-breakage connecting cylinder is located at the rear end of the epoxy resin cylinder. The anti-breakage connecting cylinder has an internal cavity with a wire opening; a data transmission line is located at the rear end of the epoxy resin cylinder; a strain gauge connecting line is connected to one end of the data transmission line, which passes through the wire opening. In use, a push rod is connected to the rear end of the anti-breakage connecting cylinder, and external force pushes the anti-breakage hollow infill stress testing device to the testing position. This utility model solves the problem of test failure due to data transmission line breakage during the installation of the hollow infill geostress testing equipment, improving the experimental success rate.

Description

Technical Field

[0001] This utility model belongs to the technical field of ground stress testing equipment, and in particular relates to a hollow envelope stress testing device that prevents wire breakage. Background Technology

[0002] Hollow inclusion geostress testing technology, as the most widely used and mature branch of stress relief methods, plays a key role in in-situ three-dimensional stress measurement of deep rock masses. It is especially suitable for relatively intact and hard rock environments, providing important data support for rock mass stability assessment in fields such as mineral resource development and underground engineering construction.

[0003] The core equipment for hollow inclusion geostress testing technology is a hollow inclusion stress gauge, which mainly includes components such as a conical directional plunger, a resin reservoir, and an epoxy resin cylinder. The epoxy resin cylinder serves as the core stress sensing element, with three strain clusters embedded in its outer wall to capture stress signals. A mounting rod is connected to the rear end of the epoxy resin cylinder for easy fixation. The plunger is installed inside the resin reservoir, and its movement within the reservoir forces the resin through a pressure-applied outlet at the top of the epoxy resin cylinder, achieving thorough consolidation with the rock mass and ensuring effective transmission of stress signals.

[0004] During installation, to ensure data accuracy, the hollow inclusion needs to be pushed to the bottom of the borehole at a depth of 15-20m to exceed the disturbance range of the surrounding rock. On-site, the inclusion is pushed using manual labor or mechanical equipment, with the push rod composed of anchor bolts connecting to the metal connecting cylinder at the end. Simultaneously, the data transmission line at the tail extends to the outside of the borehole to connect to the acquisition instrument, forming a complete data link. However, the following obvious drawbacks still exist: First, the inner wall of the borehole is not ideally smooth, often containing protrusions, rock debris, etc., causing the inclusion to experience significant frictional resistance during pushing. This requires multiple people to assist or the use of an integrated anchor bolt trolley, which is both labor-intensive and resource-intensive, and may also affect installation accuracy. Second, the transmission line is in direct contact with the push rod, making it susceptible to shear force breakage during external pushing, resulting in test failure. This not only wastes resources but may also delay the project progress, limiting the reliability of this technology in complex environments.

[0005] Therefore, a new testing device is urgently needed to ensure the smooth installation of anti-breakage wires and the effective monitoring of ground stress data. Utility Model Content

[0006] To address the shortcomings of existing technologies, this utility model provides a hollow core stress testing device for preventing wire breakage.

[0007] A hollow core stress testing device for preventing wire breakage includes a glue storage cylinder containing adhesive in its inner cavity; a conical plunger is connected to the front end of the glue storage cylinder, and an integrally formed epoxy resin cylinder is provided at the rear end of the glue storage cylinder; a glue outlet is provided at one end of the glue storage cylinder near the epoxy resin cylinder; and a wire breakage prevention connecting cylinder is provided at the rear end of the epoxy resin cylinder.

[0008] The anti-breakage connecting cylinder has an internal cavity with a wire opening on the cavity.

[0009] The epoxy resin cylinder is equipped with a data transmission line at its rear end.

[0010] To ensure the data transmission line extends smoothly outside the hole, the length of the data transmission line should be ≥20m.

[0011] Multiple strain clusters are embedded in the outer wall of the epoxy resin cylinder. The connecting line of the strain clusters is connected to one end of the data transmission line at the rear end of the epoxy resin cylinder. The data transmission line passes through the wire window, which ensures that the data transmission line can pass through one side of the hole wall and go to the outside of the hole along the detection hole.

[0012] The length of the window in the conductor is 50mm and the width is 10mm.

[0013] The anti-breakage connecting cylinder is equipped with a metal blocking plate inside. In use, the push rod applies external force to the metal blocking plate to push the testing device to the detection position.

[0014] The length from the metal blocking plate to the tail of the anti-breakage connecting cylinder is ≥100mm.

[0015] The outer diameter of the anti-breakage connecting cylinder is 22mm-25mm, and the inner diameter is 20mm.

[0016] Rubber sealing rings are fixed at the front and rear ends of the epoxy resin cylinder, respectively.

[0017] By employing the above technical solution, this utility model application has at least the following beneficial effects:

[0018] This invention solves the problem of test failure caused by data transmission line breakage during the installation of hollow inclusion geostress testing equipment, thus improving the success rate of experiments. At the same time, it can appropriately reduce the diameter of the installation hole to ensure a tighter bond between the inclusion and the rock wall, thereby improving the accuracy of the collected data. Attached Figure Description

[0019] Figure 1 A schematic diagram of the auxiliary installation device for stress testing of hollow bodies provided by this utility model;

[0020] Figure 2 for Figure 1 A magnified view of a portion of the image;

[0021] In the picture:

[0022] 1-Conical plunger, 2-Glue reservoir, 3-Rubber sealing ring, 4-Glue outlet, 5-Epoxy resin cylinder, 6-Anti-breakage connecting cylinder, 7-Wire opening, 8-Metal blocking plate. Detailed Implementation

[0023] To better explain and facilitate understanding of this utility model, the technical solution and effects of this utility model will be described in detail below with reference to the accompanying drawings and specific embodiments.

[0024] like Figures 1-2 As shown, a hollow core stress testing device for preventing wire breakage includes a glue storage cylinder 2 with an inner cavity containing adhesive. A conical plunger 1 is connected to the front end of the glue storage cylinder 2, and a solid epoxy resin cylinder 5 is located at the rear end. In this embodiment, the epoxy resin cylinder 5 and the glue storage cylinder 2 are integrally formed. A glue outlet hole 4 is provided at the end of the glue storage cylinder 2 near the epoxy resin cylinder 5. The conical plunger 1 moves within the glue storage cylinder 2, and the glue outlet hole 4 ensures the adhesive flows smoothly out of the glue storage cylinder. A wire breakage prevention connecting cylinder 6 is located at the rear end of the epoxy resin cylinder 5. The wire breakage prevention connecting cylinder 6 has an internal cavity with a wire opening 7. In use, a push rod is connected to the tail of the wire breakage prevention connecting cylinder 6, and the hollow core stress testing device is pushed to the testing position by external force.

[0025] The adhesive storage cylinder 2 is a core component of the hollow-body stress testing device for preventing wire breakage. As a carrier for the adhesive, it has an internal cavity to ensure sufficient adhesive storage for testing and to form a tight fit with the conical plunger 1. The end of the conical plunger 1 connected to the front end of the adhesive storage cylinder 2 has a conical surface design, allowing it to perfectly fit the inner wall of the cavity. When the conical plunger 1 moves axially within the adhesive storage cylinder 2, it can stably push the adhesive with uniform thrust, thereby squeezing the adhesive through the dispensing hole 4, avoiding adhesive residue or interruption of delivery due to uneven force. The epoxy resin cylinder 5 connected to the rear end of the adhesive storage cylinder 2 not only serves as a structural connection, but its dispensing hole 4 is also a crucial channel for adhesive delivery. Furthermore, to address the common problem of wire breakage during testing, the device features a dedicated anti-breakage connecting cylinder 6 at the rear end of the epoxy resin cylinder 5. The internal cavity of the anti-breakage connecting cylinder 6 provides a safe space for the data transmission line 9, preventing it from being directly exposed to friction or compression. The push rod connected to the rear end of the device serves as the operating end. By applying axial force to the push rod, the operator can smoothly and accurately push the entire testing device to the preset testing position.

[0026] Furthermore, three sets of strain clusters are embedded in the outer wall of the epoxy resin cylinder 5, each set spaced 120 degrees apart. The connecting line of the strain clusters is connected to one end of the data transmission line 9 at the rear end of the epoxy resin cylinder 5. The data transmission line 9 passes through the conductor window 7, which ensures that the data transmission line 9 can pass through one side of the hole wall and extend along the detection hole to the outside of the hole. The conductor window 7 is 50mm long and 10mm wide to ensure that the data transmission line can pass through smoothly. The other end of the data transmission line 9 is connected to the strain receiving device outside the detection hole to receive monitoring data. To ensure that the data transmission line 9 extends smoothly to the outside of the hole, the length of the data transmission line 9 is ≥20m.

[0027] Specifically, three sets of strain clusters are embedded in the outer wall of the epoxy resin cylinder 5, with each set evenly distributed at a 120-degree angle. This layout design can accurately capture stress changes from three different directions, greatly improving the comprehensiveness of stress monitoring and the accuracy of the data. The connecting line of the strain clusters is firmly connected to one end of the data transmission line 9 at the rear end of the epoxy resin cylinder 5, ensuring that the monitored stress signal can be transmitted to the data transmission line efficiently and without loss. The data transmission line 9 passes through the wire opening 7 on the cavity of the anti-breakage connecting cylinder 6, smoothly exits from one side of the detection hole wall, and extends along the extension direction of the detection hole to the outside of the hole, avoiding problems such as tangling or jamming of the transmission line inside the hole. To allow the data transmission line 9 to pass through smoothly, the wire opening 7 is set with a length of 50mm and a width of 10mm. This size provides sufficient space for the transmission line to pass through and also has a certain limiting effect on the transmission line, preventing it from shaking freely inside the hole and suffering unnecessary wear. The other end of the data transmission line 9 is connected to a strain receiving device outside the detection hole, thereby transmitting the various data monitored by the strain cluster to the receiving device in real time. This provides accurate and timely information for staff to analyze the stress at the detection location. Furthermore, to ensure that the data transmission line 9 can extend unimpeded to the outside of the hole and meet the needs of detection holes at different depths, its length is set to be no less than 20m. This ensures the continuity and stability of data transmission even in deeper detection environments.

[0028] The anti-breakage connecting cylinder 6 is made of steel, meeting the strength requirements during equipment installation. The anti-breakage connecting cylinder 6 is machined as a hollow steel column on a lathe, using a non-welded assembly to ensure the overall strength of the equipment. The anti-breakage connecting cylinder 6 contains a metal blocking plate 8 with a thickness ≥2mm, ensuring the push rod cannot penetrate the metal blocking plate 8 and preventing direct contact between the push rod and the data transmission line 9. The length from the metal blocking plate 8 to the tail of the anti-breakage connecting cylinder 6 is ≥100mm, ensuring sufficient overlap between the push rod and the anti-breakage connecting cylinder 6 to prevent slippage. The outer diameter of the anti-breakage connecting cylinder 6 is 22mm-25mm, and the inner diameter is 20mm.

[0029] Furthermore, rubber sealing rings are fixed at the front and rear ends of the epoxy resin cylinder. In this embodiment, four rubber sealing rings are provided, arranged in pairs, and fixed to the outer wall of the epoxy resin cylinder at the front and rear ends respectively. The outer diameter of the rubber sealing rings is 2mm larger than the outer diameter of the epoxy resin cylinder. The two sets of rubber rings, the outer wall of the epoxy resin cylinder, and the test hole rock wall form a hollow adhesive storage space, ensuring that the adhesive completely covers the epoxy numerical cylinder after flowing out of the adhesive outlet, ensuring a stable bond between the strain gauge and the rock wall. At the same time, due to the elasticity of the rubber sealing rings 3, they can buffer the vibration caused by external forces during the device being pushed to the detection position or during the test.

Claims

1. A stress testing device for a hollow core containing wire breakage prevention device, characterized in that: It includes a glue storage cylinder, the inner cavity of which is filled with adhesive; a conical plunger is connected to the front end of the glue storage cylinder, and an integrally molded epoxy resin cylinder is provided at the rear end of the glue storage cylinder, with a glue outlet hole opened at one end of the glue storage cylinder near the epoxy resin cylinder; and an anti-breakage connecting cylinder is provided at the rear end of the epoxy resin cylinder.

2. The hollow core stress testing device for preventing wire breakage according to claim 1, characterized in that: The anti-breakage connecting cylinder has an internal cavity with a wire opening on the cavity.

3. The hollow core stress testing device for preventing wire breakage according to claim 1, characterized in that: The epoxy resin cylinder is equipped with a data transmission line at its rear end.

4. The hollow core stress testing device for preventing wire breakage according to claim 3, characterized in that: To ensure the data transmission line extends smoothly outside the hole, the length of the data transmission line should be ≥20m.

5. The hollow core stress testing device for preventing wire breakage according to claim 3, characterized in that: Multiple strain clusters are embedded in the outer wall of the epoxy resin cylinder. The connecting line of the strain clusters is connected to one end of the data transmission line at the rear end of the epoxy resin cylinder. The data transmission line passes through the wire window, which ensures that the data transmission line can pass through one side of the hole wall and go to the outside of the hole along the detection hole.

6. The hollow core stress testing device for preventing wire breakage according to claim 2, characterized in that: The length of the window in the conductor is 50mm and the width is 10mm.

7. The hollow core stress testing device for preventing wire breakage according to claim 1, characterized in that: The anti-breakage connecting cylinder is equipped with a metal blocking plate inside. In use, the push rod applies external force to the metal blocking plate to push the testing device to the detection position.

8. The stress testing device for a hollow core containing wire breakage prevention device according to claim 7, characterized in that: The length from the metal blocking plate to the tail of the anti-breakage connecting cylinder is ≥100mm.

9. The hollow core stress testing device for preventing wire breakage according to claim 1, characterized in that: The outer diameter of the anti-breakage connecting cylinder is 22mm-25mm, and the inner diameter is 20mm.

10. The stress testing device for a hollow core containing wire breakage prevention device according to claim 1, characterized in that: Rubber sealing rings are fixed at the front and rear ends of the epoxy resin cylinder, respectively.

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