WO2020143154A1

WO2020143154A1 - Anchor rod supporting method applying deforming energy-absorbing anchor ring for preventing anchor rod from being broken and ejected

Info

Publication number: WO2020143154A1
Application number: PCT/CN2019/088695
Authority: WO
Inventors: 冯晓巍; 汪明坤; 张农; 何青源
Original assignee: 中国矿业大学
Priority date: 2019-01-11
Filing date: 2019-05-28
Publication date: 2020-07-16
Also published as: CN109751069B; CN109751069A

Abstract

Disclosed is an anchor rod supporting method applying a deforming energy-absorbing anchor ring for preventing an anchor rod from being broken and ejected, particularly suitable for soft rock large-deformation roadways or sections requiring energy-absorbing yielding supporting. According to the method, the anchor rod (1) penetrates through the anchor ring (2) having opposite holes, and by applying pressure to rock mass (10) by means of a tray (6) and a nut (4), deformation is prevented. When the stress of the anchor rod is increased, the anchor ring deforms in a direction along the opposite holes, and thus the energy-absorbing effect is achieved. The deformation amplitude of the anchor ring can be observed by utilizing fluorescent bands (3) oppositely disposed on the outer sides of the anchor ring, so that the stress of the anchor rod is pre-determined, and a warning effect on sudden breakage of a potential part is achieved. When the deformation of the anchor ring is too large or the fluorescence range is too large, anti-ejection iron wires (11) penetrate through two holes (5) which are formed at the tail portion of the anchor rod in a crossed mode, and are screwed and fixed on an iron wire net (7). If the anchor rod is broken at any key position, the two anti-ejection iron wires which are disposed in the crossed mode can prevent the anchor rod from being ejected into the space of the roadway, and people are prevented from being injured. Also disclosed is an anchor rod supporting apparatus applying a deforming energy-absorbing anchor ring for preventing an anchor rod from being broken and ejected, which is simple in structure, convenient to operate, low in economic costs, safe, reliable and good in effect.

Description

Deformation energy-absorbing anchor ring and anchor rod supporting method for preventing anchor rod from breaking and ejecting

Technical field

The invention relates to a bolt supporting method, in particular to a section suitable for soft rock large-deformation roadway or a section that needs to be supported by pressure-absorbing support, a deformation-energy-absorbing anchor ring for protecting the safety of miners, and prevention of bolt ejection from breaking Anchor support method.

Background technique

Bolt support technology plays an extremely important role in the field of coal mine support in my country, with obvious economic and technical benefits, so it is widely promoted and applied. In recent years, with the increase in the depth of coal mining, many mines can encounter soft rock large deformation tunnels or tunnels with impact tendency such as rock bursts. Such tunnels have high original rock stress and complicated stress disturbance, and most tunnels have to bear once Or multiple excavation disturbances. At present, most projects tend to adopt dense support, lengthened support, super support and other solutions to deal with this problem, but it has brought a series of problems such as increased cost, complicated operation, and slow construction period.

Undoubtedly, under the above engineering technology background, the bolt support technology still has a high general applicability. In order to cope with and adapt to the above-mentioned engineering geological conditions, many domestic and foreign scholars have proposed in recent years: under high-stress conditions of soft rock or impact-prone tunnel support, the supporting member must have a certain ability to withstand deformation, and the supporting member must be able to adapt Deformation of the rock mass. For example, the constant resistance large deformation anchor bolt proposed by Academician He Manchao in our country, and the D-type anchor bolt proposed by Professor Charlie C. Li of Norwegian University of Science and Technology, these bolts are used in soft rock high stress roadways and impact-prone roadways. It has achieved very ideal economic and technological effects and has a very wide influence.

On the other hand, when the force of the anchor rod exceeds its own strength, a sudden fracture of the anchor rod will occur, resulting in a large impact force in an instant. This impact force originates from the deformation energy of the rock mass, and the deformation of the rock mass concentrates this energy on the anchor rod body, forcing the latter to withstand a very high pretension on the rod body. At the moment of fracture, the external components of the rock mass will shoot like an "off-string arrow" or "bullet" into the open space of the roadway, causing huge damage to the operators and equipment in the open space. Whether it is nut ejection or broken rod ejection, there are huge potential safety hazards. In my country's Huainan mining area and Shandong Xinwen mining area, equipment damage and casualty accidents occur every year due to sudden ejection of roadway bolt support components.

In response to the above problems, there is currently no sound scientific early warning system or measures. Some coal mines use the method of "capping" or "winding wire" at the end of the anchor rod to prevent potential fracture ejection, which is blind and unpredictable. However, this method is adopted for all anchor support systems, and some anchor support systems did not actually eject during the normal service of the roadway, which would cause problems such as long operation time and slow down the driving speed.

Summary of the invention

Technical problem: The purpose of the present invention is to overcome the shortcomings in the prior art, to provide a method of simple and easy to operate, low cost, strong adaptability, deformation prevention energy absorption anchor ring that can prevent accidents and prevention of anchor rod breakage The ejection bolt support method is especially suitable for soft rock high-stress roadways or roadways with impact tendency.

Technical solution: The deformable energy-absorbing anchor ring and the anchor rod supporting method for preventing the ejection of the anchor rod from breakage include anchor rods that extend into the borehole and are fixed by an anchoring agent, and are sequentially arranged on the exposed anchor rods of the hole with wire mesh, The tray and the nut are provided with two holes at the tail end of the anchor rod that are crossed in a cross shape at the tail of the anchor rod, and an anchor ring is provided between the tray and the nut. The opposite holes on the rod, the contact ends of the anchor ring with the tray and the nut are flat, respectively are the fitting surface of the anchor ring nut end and the anchor ring tray end fitting surface, and the outer arc surfaces on both sides of the anchor ring fitting surface Two fluorescent bands are laid respectively on the top.

The inner diameter of the anchor ring is 90-110mm, the outer diameter is 120-140mm, the height of the anchor ring in the axial direction is 30-50mm, the diameter of the opposite hole of the anchor rod is 19-23mm, the anchor The opposite holes of the ring are divided into anchor ring nut end openings and anchor ring tray end openings, and rubber washers are set in the opposite hole holes, respectively, anchor ring nut end opening rubber washers and anchor ring tray end opening rubbers washer.

The width of the anchor ring opposite hole and the end of the anchor ring is 50-60mm, and the length is equal to the height of the anchor ring in the axial direction; the end of the anchor ring and the end of the anchor ring The width is 30-40mm, and the length is equal to the height of the anchor ring in the axial direction.

The two fluorescent bands (3) are arranged symmetrically. The center angle of the anchor ring is 90° along the outer circumference of the anchor ring. The center line is perpendicular to the axis of the opposite hole of the anchor ring. The inside of the plastic fluorescent tape is divided into two rooms: the inner layer is the inner layer of the fluorescent tape encapsulated with ester compounds and fluorescent dyes (3-1), and the outer layer is the outer layer of the fluorescent tape encapsulated with peroxide (3- 2), the inner layer (3-1) of the fluorescent band machine glass is located in the middle.

The anchor ring is made of alloy steel with a yield strength of 180-200MPa.

The hole at the tail of the anchor is provided with two cross-shaped holes at the tail end of the anchor, the hole diameter is 3-5mm, the distance between the two holes is 20-30mm, and the outer hole is 10-30mm from the end of the anchor .

A deformation energy-absorbing anchor ring using the device of claim 1 and a bolt supporting method for preventing the ejection of the bolt from breaking, including drilling holes at a predetermined rock mass location, inserting an anchoring agent, and drilling into the anchor rod ; The specific support steps are as follows:

(1) Press the tray on the wire mesh at the hole of the drilling hole, check the opening of the anchor ring nut end of the opposite hole on the anchor ring and the inner ring of the anchor ring nut end of the anchor ring tray end rubber gasket and anchor ring The position of the rubber gasket at the end of the tray, check the fitting of the fluorescent tape, and then pass the opening of the end of the anchor ring tray end of the anchor ring tray end of the anchor ring into the anchor rod, and then connect the anchor ring The opening of the nut end of the anchor ring on the side of the fitting surface of the nut end penetrates the anchor rod, and the anchor ring is pressed against the tray;

(2) Pass the nut through the tail of the anchor rod, tighten it on the anchor ring, and apply the specified torque with the machine tool according to the prior art;

(3) Observe the deformation of the anchor ring. When the anchor ring is deformed, the fluorescent band deforms accordingly. When the anchor ring is deformed by more than 30% along the diameter of the opposite hole, the inner layer of the fluorescent band machine in the middle of the fluorescent band begins to break, and the fluorescent band machine The ester compounds and fluorescent dyes in the inner layer of glass react with the peroxide in the outer layer of the fluorescent band outside the inner layer of plexiglass to release fluorescence; the greater the deformation of the anchor ring, the more the broken range of the inner layer of the organic band of the fluorescent band The greater the intensity of the fluorescence, the greater the stress on the anchor ring, and the greater the probability of catapult ejection potential;

(4) When the deformation of the anchor ring in the direction of the opposing hole exceeds two-thirds, or the range of fluorescence diffusion in the fluorescent band exceeds two-thirds of the length of the fluorescent band, use two bulletproof wire to pass through the tail of the anchor Perforation, the two ends of the bulletproof wire are respectively fastened and fixed on the wire mesh near the tray, and the two bulletproof wires show a cross-shaped distribution;

(5) When the stress of the anchor rod body reaches the load limit and the anchor rod breaks, whether it is the sudden ejection of the tray and the nut, or the sudden ejection of the anchor ring, it will be blocked by the cross-shaped and distributed bulletproof wire.

Beneficial effect: The present invention is especially suitable for soft rock high-stress roadways or roadways with impact tendency, has deformation energy absorption characteristics, adapts to rock deformation; can pre-warn broken catapults of key parts of the bolt support system, and adopt measures in time to prevent accidents occur. Advantages compared to existing technology:

1) It has the advantages of deformation energy absorption. By adopting an additional anchor ring between the tray and the nut, the yield strength of the anchor ring is lower than the yield strength of the anchor rod, and deformation takes priority over the anchor rod. The anchor ring is deformed in the axial direction of the opposite hole, which can be changed from "non-shrinkable support" to "shrinkable support" or "flexible support", which enhances the adaptability of the anchor support system to rock deformation, Coordinated the inconsistency between rock mass deformation and bolt deformation, and delayed the premature failure of the bolt support system under the deformation of excessive rock mass. In addition, rubber gaskets are set in the opposite holes of the anchor ring, which avoids the hard contact between the anchor rod body and the wall of the opposite hole hole, and also avoids the stress concentration of the anchor rod on the anchor rod body during the deformation process.

2) It has an early warning function for broken ejection. The inner side of the fluorescent band with the anchoring ring outer wall fixed with peroxides, ester compounds and fluorescent dyes, wherein the peroxide is the outer layer, and the ester compounds and the fluorescent dyes are packaged through the organic glass as the inner layer. The fluorescent band also deforms with the deformation of the anchor ring. When the deformation range exceeds the bending limit of the plexiglass, the inner layer liquid and the outer layer liquid mix to produce a fluorescent effect. The greater the deformation of the anchor ring, the greater the rupture range of the plexiglass, and the stronger the fluorescence intensity, indicating that the anchor ring is subjected to more stress, and the greater the probability of ejection of the anchor rod fracture.

(3) It has the function of breaking bulletproof. When the deformation of the anchor ring in the direction of the opposing hole exceeds two-thirds, or when the fluorescent diffusion range in the fluorescent band exceeds two-thirds of the length of the fluorescent band, two bullet-proof wires are used to pierce through the tail of the anchor rod and tighten Fixed on the wire fence near the tray. When the stress of the anchor rod body reaches the load-bearing limit and the anchor rod is broken, no matter the sudden ejection of the tray and the nut, or the sudden ejection of the anchor ring and the anchor rod, they can be blocked by the cross-shaped and distributed bulletproof wire. It can improve the safety of underground personnel and equipment. Relying on the anchor ring, there is no need to add bulletproof wire when installing each anchor rod, and only need to add bulletproof wire to the anchor rod with the possibility of ejection at a later stage, thereby improving construction efficiency.

(4) The cost is low, the method is simple and easy to operate, and the adaptability is strong.

BRIEF DESCRIPTION

Figure 1 is a cross-sectional view of the present invention when it is actually applied;

Figure 2 is a three-dimensional view of the tail end of the present invention when it is actually applied;

3 is a three-dimensional view of the anchor ring at the fitting end of the nut of the present invention;

FIG. 4 is a three-dimensional view of the anchoring ring at the fitting end of the tray in the present invention;

5 is a cross-sectional view when the anchor ring is deformed in the actual application of the present invention;

6 is a top view of FIG. 5 in the present invention.

1-anchor, 2-anchor ring, 3-fluorescent band, 4-nut, 5-anchor end opening, 6-tray, 7-barbed wire, 8-drilled hole, 9-anchoring agent, 10-rock mass , 11- bulletproof wire.

2-1-Anchor ring nut end opening, 2-2-Anchor ring nut end opening rubber washer, 2-3-Anchor ring nut end fitting surface, 2-4-Anchor ring tray end opening, 2-5 -Anchor ring tray end opening rubber gasket, 2-6-anchor ring tray end fitting surface, 3-1-fluorescence with machine glass inner layer, 3-2-fluorescence band outer layer.

detailed description

The present invention is further described below with reference to the embodiments in the drawings:

As shown in FIG. 1, the deformable energy-absorbing anchor ring and the anchor supporting device for preventing the ejection of the anchor rod from breaking include the anchor rod 1 that extends into the borehole 8 and is fixed by the anchoring agent 9 and is sequentially arranged at the orifice A barbed wire 7, a tray 6 and a nut 4 are provided on the exposed anchor rod 1. Two tail holes 5 at the rear end of the anchor rod 1 are provided at the tail of the anchor rod 1 and are arranged between the tray 6 and the nut 4 Anchor ring 2, which has a facing hole pierced on the anchor rod 1, and the contact end of the anchor ring 2 with the tray 6 and the nut 4 is a plane, which is the fitting surface of the nut end of the anchor ring and the anchor, respectively Two fluorescent bands 3 are respectively laid on the outer circular arc surfaces of the upper and lower sides of the bonding surface of the ring tray end and the anchor ring 2.

The inner diameter of the anchor ring 2 is 90-110mm, the outer diameter is 120-140mm, the height of the anchor ring in the axial direction is 30-50mm, and the diameter of the opposite hole of the anchor rod 1 is 19-23mm The opposite holes of the anchor ring are divided into the anchor hole end opening 2-1 and the anchor ring tray end opening 2-4, and the opposite hole holes are all covered with rubber washers, which are respectively the anchor ring nut end opening rubber washers 2-2 and Anchor ring tray end rubber gasket 2-5.

The opposite hole of the anchor ring 2 is attached to the tray 6 and the width of the end fitting surface 2-6 of the end of the anchor ring is 50-60mm, the length is equal to the height of the anchor ring in the axial direction; the end of the anchor ring is attached to the nut 4 The width of the fitting surface 2-3 of the nut end is 30-40mm, and the length is equal to the height of the anchor ring in the axial direction.

The two fluorescent bands 3 are arranged symmetrically. The center angle of the anchor ring is 90° along the outer circumference of the anchor ring. The center line is perpendicular to the axis of the opposite hole of the anchor ring. Part is the inner and outer houses, the inner layer is the inner layer of the fluorescent bandage encapsulated with ester compounds and fluorescent dyes 3-1, the outer layer is the outer layer of the fluorescent bandage encapsulated with peroxides 3-2, the inner part of the fluorescent bands is the machine glass Layer 3-1 is located in the middle. The ester compound uses bis-oxalate, and the peroxide is hydrogen peroxide. When the two are mixed, energy will be released, which will be transferred to the fluorescent pigment molecules, and the fluorescent dye will then release energy in the form of visible light.

The anchor ring 2 is made of alloy steel and has a yield strength of 180-200 MPa.

The rear end of the anchor rod 1 is provided with two cross-shaped cross-shaped anchor end openings 5 with a hole diameter of 3-5mm, the distance between the two holes is 20-30mm, and the outer hole is 10 away from the end of the anchor -30mm.

The specific steps of the deformation energy-absorbing anchor ring and the anchor rod supporting method for preventing the bolt from breaking and ejecting are as follows:

1. Drill the hole 8 according to the established rules for the predetermined rock mass 10, remove the cuttings through the blow hole, insert the anchoring agent 9, and drill the anchor rod 1;

2. Press the tray 6 on the wire mesh 7 at the hole of the drill hole, check the anchor ring nut opening 2-1 and the anchor ring tray opening 2-4 inner anchor ring nut of the opposite hole on the anchor ring 2 The position of the rubber gasket 2-2 at the end and the rubber gasket 2-5 at the end of the anchor ring tray. Check the fitting of the fluorescent tape 3, and then the bonding surface 2-6 of the anchor ring tray end of the anchor ring 2 The opening 2-4 on the side of the anchor ring tray on one side penetrates into the anchor rod 1, and then the hole 2-1 on the end of the anchor ring nut end on the fitting surface of the anchor ring nut 2-1 penetrates into the anchor rod to insert the anchor ring 2 Tighten the tray;

3. Pass the nut 4 through the tail of the anchor rod and tighten it on the anchor ring, and tighten the screw thread on the anchor ring 2 through the tail of the anchor rod 1, apply the specified torque with the construction machine to lock the nut;

4. Observe the deformation of the anchor ring 2. When the anchor ring is deformed, the fluorescent band deforms accordingly. When the deformation of the anchor ring 2 along the diameter of the opposed hole exceeds 30%, the fluorescent band 3 in the middle of the fluorescent band 3 has the organic glass inner layer 3-1 Cracked, the ester compound and fluorescent dye in the inner layer 3-1 of the fluorescent band organic glass reacted with the peroxide in the outer layer 3-2 of the fluorescent band to release fluorescence; the greater the deformation of the anchor ring 2, the fluorescent band The larger the rupture range of the inner glass layer 3-1, the stronger the intensity of fluorescence, which indicates that the anchor ring 2 is subjected to more stress, and the greater the probability of the ejection of the anchor rod breaking;

5. When the deformation of the anchor ring 2 in the direction of the opposing hole exceeds two thirds, or the fluorescent diffusion range in the fluorescent band 3 exceeds two thirds of the length of the fluorescent band, two bulletproof wires 11 are used to penetrate the anchor rod respectively The perforation 5 in the tail, the two ends of the bulletproof wire 7 are respectively tightened and fixed on the wire mesh 7 near the tray, and the two bulletproof wires 11 have a cross-shaped distribution;

6. When the stress of the rod body of the anchor rod 1 reaches the load limit and the anchor rod breaks, whether the sudden ejection of the tray 6, the nut 4, or the sudden ejection of the anchor ring 1, will be blocked by the cross-shaped and distributed bulletproof wire , Can effectively protect the safety of underground equipment and personnel.

Claims

A deformable energy-absorbing anchor ring and an anchor rod supporting device for preventing the ejection of the anchor rod from breakage, which includes an anchor rod (1) extending into a borehole (8) and fixed by an anchoring agent (9), which is sequentially arranged and exposed at the opening A barbed wire (7), a tray (6) and a nut (4) on the anchor rod (1), characterized in that two ends of the anchor rod (1) are provided at the end of the anchor rod (1) with a cross in a cross shape A hole (5), an anchor ring (2) is provided between the tray (6) and the nut (4), the anchor ring (2) is provided with an opposite hole that is sleeved on the anchor rod (1), and the anchor The contact ends of the ring (2) and the tray (6) and the nut (4) are flat, which are the fitting surface (2-3) of the nut end of the anchor ring and the fitting surface (2-6) of the tray end of the anchor ring, the anchor ring respectively (2) Two fluorescent bands (3) are respectively laid on the outer arc surfaces of the upper and lower sides of the bonding surface.
The deformable energy-absorbing anchor ring and the anchor rod supporting device for preventing ejection of the anchor rod according to claim 1, characterized in that the inner diameter of the anchor ring (2) is 90-110mm, and the outer diameter is 120 -140mm, the height of the anchor ring in the axial direction is 30-50mm, the diameter of the opposite hole of the anchor rod (1) is 19-23mm, the opposite hole of the anchor ring is divided into the opening of the end of the anchor ring nut (2-1) and anchor ring tray end openings (2-4), the opposite holes are covered with rubber washers, respectively, anchor ring nut end opening rubber washers (2-2) and anchor ring tray end openings Hole rubber washer (2-5).
The deformable energy-absorbing anchor ring and the anchor rod supporting device for preventing the bolt from breaking and ejecting according to claim 1 or 2, characterized in that: the opposite hole of the anchor ring (2) is fit to the tray (6) The width of the end fitting surface (2-6) of the end of the anchor ring tray is 50-60mm, and the length is equal to the height of the anchor ring in the axial direction; the end surface of the anchor end of the anchor ring (2-3) is attached to the nut (4) ) Has a width of 30-40 mm and a length equal to the height of the anchor ring in the axial direction.
The deformable energy-absorbing anchor ring and the anchor supporting device for preventing the bolt from breaking and ejecting according to claim 1, characterized in that the two fluorescent bands (3) are arranged symmetrically, and the fluorescent bands (3) are along The center angle of the anchor ring corresponding to the outer circumference of the anchor ring is 90°. The center line is perpendicular to the axis of the opposite hole of the anchor ring. The inside of each plastic fluorescent strip is divided into two layers, the inner layer is encapsulated with ester compounds and The inner surface of the fluorescent band of the fluorescent dye (3-1), the outer layer is the outer layer (3-2) of the fluorescent band encapsulated with peroxide, and the inner layer of the fluorescent band (3-1) is located in the middle.
The deformable energy-absorbing anchor ring and the anchor rod supporting method for preventing the ejection of the anchor rod according to claim 1, characterized in that the anchor ring (2) is made of alloy steel, and the yield strength is 180- 200MPa.
The deformable energy-absorbing anchor ring and the anchor rod supporting method for preventing the bolt from breaking and ejecting according to claim 1, characterized in that: the anchor rod (1) is provided with two cross-shaped anchors spaced at the tail The hole diameter of the hole (5) at the end of the rod is 3-5mm, the distance between the two holes is 20-30mm, and the outer hole is 10-30mm away from the end of the anchor rod.
A deformation energy-absorbing anchor ring using the device of claim 1 and a bolt supporting method for preventing the ejection of the bolt from breaking, including drilling holes at a predetermined rock mass location, inserting an anchoring agent, and drilling into the anchor rod ; It is characterized by specific support steps as follows:

(1) Press the tray (6) on the wire mesh (7) at the hole of the drilling hole, and check the opening (2-1) and the end of the anchor ring tray of the anchor hole (2) of the opposite hole on the anchor ring (2) The position of the rubber gasket (2-2) at the end of the anchor ring nut and the rubber gasket (2-5) at the end of the anchor ring tray at the opening (2-4), check the fitting and fixing of the fluorescent tape (3), Then first insert the hole (2-4) on the anchor ring tray end side of the anchor ring tray end fitting surface (2-6) of the anchor ring (2) into the anchor rod (1), and then connect the anchor ring nut end The hole (2-1) at the end of the anchor ring nut on the side of the fitting surface (2-3) penetrates the anchor rod (1), and presses the anchor ring (2) against the tray (6);

(2) Pass the nut (4) through the tail of the anchor rod, tighten it on the anchor ring (2), and apply the specified torque with the machine tool according to the prior art;

(3) Observe the deformation of the anchor ring (2). When the anchor ring (2) is deformed, the fluorescent band (3) deforms accordingly. When the anchor ring (2) is deformed by more than 30% along the diameter of the opposite hole, the fluorescent band (3) The inner layer (3-1) of the fluorescent organic glass begins to crack, and the ester compounds and fluorescent dyes in the inner layer (3-1) of the fluorescent organic glass ooze out and the outer layer of the fluorescent tape (3-2) outside the organic glass ) Reacts with the peroxide and releases fluorescence; the greater the deformation of the anchor ring (2), the greater the rupture range of the inner layer (3-1) of the fluorescent glass with organic glass, and the stronger the fluorescence intensity, indicating that the anchor ring (2) will withstand The greater the stress, the greater the probability of bolt ejection potential to occur;

(4) When the deformation of the anchor ring (2) in the direction of the opposed hole exceeds two thirds, or the fluorescent diffusion range in the fluorescent band (3) exceeds two thirds of the length of the fluorescent band, use two bulletproof wire Through the perforation at the end of the anchor rod, the two ends of the bullet-proof wire are respectively fastened and fixed on the wire mesh near the tray, and the two bullet-proof wires show a cross-shaped distribution;

(5) When the stress of the anchor rod body reaches the load limit and the anchor rod breaks, whether it is the sudden ejection of the tray (6), the nut (4), or the sudden ejection of the anchor ring (1), they will be distributed in a cross shape Blocked by bulletproof wire.