Anchoring rod based on inductive displacement measurement for fishbone type composite structure

Abstract

This invention provides a fishbone-shaped composite structure anchor bolt based on inductive displacement measurement. The device mainly includes a protective cap, fastener, pressure plate, anchor seat, and waist beam in the anchor head section; a cylindrical steel shell, connecting rod, induction coil, sleeve, and inductive displacement measurement sensor in the free section; as well as reinforcing bars, a grout-stopping ring, and a centering bracket. The anchoring section mainly includes a fishbone-shaped anchoring structure, reinforcing bars, and a centering bracket. The cylindrical steel shell contains an inductive displacement measurement sensor, including an induction coil and an armature. A cylindrical steel shell is installed near the end of the free section of the anchor bolt, connected to the grout-stopping ring by the connecting rod. A fishbone-shaped anchoring structure is installed in the anchoring section to strengthen the anchoring force. By measuring the movement data of the armature, the displacement and stress changes caused by rock stress on the anchor bolt can be accurately measured. This anchor bolt has advantages such as high stress measurement accuracy, enhanced anchoring performance, and strong anti-interference ability. It also features simple construction technology and convenient installation.

Description

Technical Field

[0001] This utility model relates to the field of geotechnical engineering technology, specifically to a fishbone-type composite structure anchor rod based on inductive displacement measurement. Background Technology

[0002] In geotechnical engineering, the safety and stability of structures such as slopes, tunnels, and embankments are crucial for ensuring the safety of personnel and property and the smooth progress of projects. After the excavation of a project or slope is completed, the original static equilibrium of the rock mass is disrupted, leading to significant changes in the stress distribution of the rock strata. To suppress excessive deformation and crack expansion in the surrounding rock, anchoring technology is widely used for rock mass support. Anchor bolt support not only deforms in tandem with the surrounding rock, buffering concentrated deformation areas, but also effectively controls surrounding rock deformation, improving the overall stability of slopes and tunnels.

[0003] As depth increases and geological conditions become increasingly complex, traditional strut support schemes are gradually revealing their vulnerability to earthquake hazards. Static support alone is insufficient to meet the needs of long-term monitoring and dynamic assessment, necessitating the introduction of new support structures with both construction and monitoring capabilities. Utility Model Content

[0004] The technical problem to be solved by this utility model is to provide a fishbone-shaped composite structure anchor rod based on inductive displacement measurement. This device integrates inductive displacement measurement technology with a fishbone-shaped anchoring structure to achieve high-precision monitoring of the stress state of the anchor rod and a significant improvement in anchoring performance.

[0005] To solve the above-mentioned technical problems, this utility model provides the following technical solution:

[0006] A fishbone-shaped composite anchor bolt based on inductive displacement measurement includes an anchoring section, a free section, and an anchor head section. The anchor head section includes a protective cap, a fastener, a pressure plate, an anchor seat, and a waist beam, with the fastener, pressure plate, anchor seat, and waist beam sequentially sleeved on the reinforcing bar. The free section includes a sleeve, a grout-stopping ring, a cylindrical steel shell, an inductive displacement sensor, and a connecting rod. The grout-stopping ring is located on the sleeve near the anchoring section. The cylindrical steel shell contains an inductive displacement sensor, an induction coil, and an armature. The anchoring section includes a reinforcing bar, a centering bracket, and a fishbone-shaped anchoring structure. The fishbone-shaped anchoring structure is located on the outside of the reinforcing bar, and centering brackets perpendicular to the reinforcing bar are installed at both ends of the reinforcing bar.

[0007] Preferably, when the composite structure anchor is installed into the slope, a retaining structure perpendicular to the anchor head section is also installed. The retaining structure is located on the slope surface to prevent the surface soil and shallow soil of the slope from sliding down.

[0008] Preferably, the reinforcing bar is provided with external threads at the anchor head section, and the fastener, pressure plate, anchor seat, and waist beam are sequentially installed on the reinforcing bar through threaded connections. One side of the waist beam is connected to the support structure, the other side of the waist beam is connected to one side of the anchor seat, the other side of the anchor seat is connected to one side of the pressure plate, the other side of the pressure plate is connected to the fastener, and the protective cap is installed on the anchor seat and covers the fastener and pressure plate.

[0009] Preferably, when the composite structure anchor is installed into the slope, a hole is drilled in the slope, wherein the anchoring section is located in the deep stable rock and soil of the hole, and is embedded in the anchor body formed by the adhesive through a combination of fishbone-shaped anchoring structure and steel reinforcement, so as to achieve multi-directional locking between the end of the anchor and the potential sliding surface in the deep rock and soil.

[0010] Preferably, the cylindrical steel shell is fixedly installed on the free section near the anchor head section, the armature inside the cylindrical steel shell is connected to the reinforcing bar of the adjacent anchor head section, and an induction coil is installed on the outside of the armature.

[0011] Preferably, the cylindrical steel shell is connected to the centering bracket in the anchoring section by at least two sets of connecting rods.

[0012] Preferably, the anchoring section is bonded to deep stable rock and soil by grouting.

[0013] The beneficial effects of the above-mentioned technical solution of this utility model are as follows:

[0014] This invention, on the one hand, utilizes a fishbone-shaped anchoring structure added to the anchoring section to form multi-point anchoring, thereby strengthening the anchoring force generated by the anchor bolt; on the other hand, it uses an inductive displacement sensor to monitor the displacement and stress changes of the anchor bolt under the action of the surrounding rock. It features high measurement accuracy, convenient construction, and strong anti-interference capabilities, overcoming the shortcomings of traditional monitoring methods and adapting to the dynamic monitoring needs of consolidated structure performance in complex geological environments. Attached Figure Description

[0015] Figure 1 This is a schematic diagram of the anchoring system structure of the present invention;

[0016] Figure 2 This is a cross-sectional view of the anchoring system of the present invention;

[0017] Figure 3 This is a schematic diagram of the structure of the inductive displacement measurement sensor of the present invention.

[0018] Among them: 1-protective cap, 2-fastener, 3-pressure plate, 4-anchor seat, 5-waist beam, 6-reinforcing bar, 7-sleeve, 8-anchor body, 9-support structure, 10-potential sliding surface, 11-anchoring section, 12-free section, 13-anchor head section, 14-centering bracket, 15-grout stop ring, 16-adhesive, 17-surface soil and rock, 18-shallow soil and rock, 19-drill hole, 20-stabilized soil and rock, 21-cylindrical steel shell, 22-inductive displacement sensor, 23-induction coil, 24-connecting rod, 25-fishbone-shaped anchoring structure, 26-armature. Detailed Implementation

[0019] To make the technical problems, technical solutions and advantages of this utility model clearer, a detailed description will be given below in conjunction with the accompanying drawings and specific embodiments.

[0020] like Figures 1 to 3 As shown, an embodiment of this utility model provides a fishbone-shaped composite structure anchor bolt based on inductive displacement measurement, including a protective cap 1, fastener 2, pressure plate 3, anchor seat 4, and waist beam 5 in the anchor head section, and a cylindrical steel shell 21, sleeve 7, inductive displacement measurement sensor 22, as well as reinforcing bars 6, grout stop ring 15, and centering bracket 14 in the free section; the anchoring section includes a fishbone-shaped anchoring structure 25, reinforcing bars 6, and centering bracket 14; the cylindrical steel shell 21 is connected to the centering bracket 14 of the anchoring section by a connecting rod 24, and the sleeve is set in the free section, and the rod body is fixed by the centering bracket to ensure that the rod body is arranged inside the sleeve. The inside of the steel shell includes an inductive displacement measurement sensor 22, an induction coil 23, and an armature 26. The fishbone-shaped anchoring structure 25 is set in the anchoring section, and through its unique geometric shape, it forms multi-point anchoring after grouting and consolidation, significantly enhancing the anchoring capacity between the anchor bolt and the rock mass. The cylindrical steel shell 21 is located in the free section near the anchor head section and is rigidly connected to the centering bracket 14 of the anchoring section via the connecting rod 24. When the surrounding rock deforms, the anchor rod is mainly subjected to tensile forces, resulting in displacement, while the inductive coil inside the sleeve remains stationary, causing the armature 26 connected to the reinforcing bar and the induction coil 23 to undergo axial relative displacement. This displacement change causes a change in the magnetic field strength of the induction coil, and the amount of anchor rod deformation displacement can be fed back in real time through the data processing terminal. The stress state of the anchor rod can be obtained by calculating the elastic modulus of the reinforcing bar.

[0021] The specific construction process is as follows:

[0022] (1) Drilling: Based on the design scheme and on-site geological conditions, select a suitable drilling rig and carry out drilling operations in the rock mass layer to provide space for the subsequent installation of anchor bodies.

[0023] (2) Rod fabrication: A fishbone-type composite structure anchor rod based on inductive displacement measurement includes an anchor head section 13, a free section 12, and an anchoring section 11. The anchor rod is wrapped with a sleeve 7, and a cylindrical steel shell 21 is installed using a connecting rod 24, which contains an inductive displacement measurement sensor 22. The anchoring section 11 is equipped with a fishbone-shaped anchoring structure 25.

[0024] (3) Anchoring: The prepared rod is installed into the borehole 19. Grouting is performed in the anchoring section 11, which is bonded to the deep stable soil and rock 20 through grouting. The anchoring section of the anchor rod adopts a special fishbone-shaped anchoring structure 25 to ensure that multiple anchoring points are formed after grouting consolidation to strengthen the anchoring force, thereby consolidating the shallow soil and rock with the deep soil and rock to maintain the stability of the surrounding rock itself.

[0025] (4) Anchor bolt tensioning: After the grouting has solidified, the anchor bolts are tensioned. This process ensures that the anchored section remains stable at the specified strength and locks the bolt body. If necessary, multiple tensioning operations can be performed.

[0026] (5) Zeroing: After the anchor bolt is locked, the inductive displacement sensor 22 needs to be zeroed to ensure that the monitoring system accurately reflects the displacement change.

[0027] (6) Monitoring Readings: The deformation and displacement of the anchor bolts are monitored in real time through data analysis to calculate the stress state of the anchor bolts. The data processing terminal is used to monitor changes in the stress state of the anchor bolts and the surrounding rock pressure, allowing for timely measures to ensure construction safety. The specific principle for calculating the stress state of the anchor bolts is as follows:

[0028] A cylindrical steel shell is installed near the anchor head section in the free section. Tensile deformation of the anchor bolt typically occurs in the free section. When rock deformation causes tensile stress on the anchor bolt, the armature, connected to the reinforcing steel, experiences axial displacement. The cylindrical steel shell, rigidly connected to the anchor bolt via a connecting rod and centering bracket, maintains a constant relative position. Therefore, the relative displacement between the armature and the induction coil inside the steel shell changes the inductance value of the induction coil. The relationship between the change in the inductance sensor coil and the length of the armature entering the coil can be expressed as:

[0029]

[0030] In formula (1): L This refers to the inductance value of the sensor coil. l The length of the coil; r The average radius of the coil; N This represents the number of turns in the coil. l a The length of the armature entering the coil; r a For the armature radius, The effective permeability of the iron core.

[0031] The displacement and stress changes of the anchor bolt under the action of the surrounding rock can be measured by converting the change of the inductive sensor coil with the length of the armature entering the coil.

[0032] The above description is the preferred embodiment of this utility model. It should be noted that for those skilled in the art, several improvements and modifications can be made without departing from the principle of this utility model, and these improvements and modifications should also be considered within the protection scope of this utility model.

Claims

1. A fishbone type composite structure anchor rod based on inductive displacement measurement, characterized by, Includes the anchorage section, the free section, and the anchor head section; The anchor head section includes a protective cap, a fastener, a pressure plate, an anchor seat, and a waist beam, wherein the fastener, pressure plate, anchor seat, and waist beam are sequentially sleeved on the reinforcing bar; The free section includes a sleeve, a grout stop ring, a cylindrical steel shell, an inductive displacement sensor, and a connecting rod. The grout stop ring is located on the sleeve near the anchoring section. The cylindrical steel shell is equipped with an inductive displacement sensor, an induction coil, and an armature. The anchoring section includes reinforcing bars, centering brackets, and fishbone-shaped anchoring structures. The fishbone-shaped anchoring structures are provided on the outer side of the reinforcing bars, and centering brackets perpendicular to the reinforcing bars are installed at both ends of the reinforcing bars.

2. Fishbone composite structure anchor rod based on inductive displacement measurement according to claim 1, characterized in that, When the composite anchor is installed into the slope, a retaining structure perpendicular to the anchor head section is also installed, and the retaining structure is located on the slope surface.

3. Fishbone composite structure anchor rod based on inductive displacement measurement according to claim 2, characterized in that, The reinforcing bar is provided with external threads at the anchor head section. The fastener, pressure plate, anchor seat, and waist beam are sequentially installed on the reinforcing bar through threaded connections. One side of the waist beam is connected to the support structure, the other side of the waist beam is connected to one side of the anchor seat, the other side of the anchor seat is connected to one side of the pressure plate, and the other side of the pressure plate is connected to the fastener. The protective cap is installed on the anchor seat and covers the fastener and pressure plate.

4. Inductive displacement measurement based fishbone composite structure anchor rod according to claim 1, characterized in that, When the composite structure anchor is installed into the slope, a hole is drilled in the slope, and the anchoring section is located in the deep stable rock and soil of the hole. It is embedded in the anchor body formed by the adhesive through a combination of fishbone-shaped anchoring structure and steel reinforcement.

5. Inductive displacement measurement based fishbone composite structure anchor rod according to claim 1, characterized in that, The cylindrical steel shell is fixedly installed on the free section near the anchor head section. The armature installed inside the cylindrical steel shell is connected to the reinforcing bar of the adjacent anchor head section, and an induction coil is installed on the outside of the armature.

6. Inductive displacement measurement based fishbone composite structure anchor rod according to claim 1, characterized in that, The cylindrical steel shell is connected to the centering bracket in the anchoring section by at least two sets of connecting rods.

7. Inductive displacement measurement based fishbone composite structure anchor rod according to claim 4, characterized in that, The anchoring section is bonded to the deep stable rock and soil through grouting.

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