Birdcage-shaped anchor cable with resistance increasing device

Abstract

An anchoring section of the anchor cable extends out of a butterfly-shaped tray and is connected with an anchor cable anchorage device, a non-anchoring section of the anchor cable is inserted into surrounding rock, a plurality of resistance increasing devices are arranged on a steel strand in the center of the non-anchoring section in a penetrating mode at equal intervals, and a birdcage-shaped structure is arranged on the non-anchoring section at the resistance increasing devices. When the birdcage-shaped anchor cable is arranged in broken surrounding rock, due to the resistance increasing effect of the birdcage-shaped inner spindle-shaped resistance increasing device, the resistance between the anchor cable and the surrounding rock is improved, meanwhile, the birdcage shrinkage deformation caused by impact of the surrounding rock is reduced, it is guaranteed that the anchor cable and the surrounding rock are bonded into a whole through anchoring agents, and the service life of the anchor cable is prolonged. And the effective acting force of anchoring surrounding rock by the anchor cable is fully exerted.

Description

Technical Field

[0001] The utility model relates to the field of roadway support equipment, and particularly relates to a cage-shaped anchor cable with a resistance increasing device. Background Art

[0002] The treatment of floor heave in coal mine roadways has always been a difficult problem in roadway support. Since the floor is the weakest link in the entire roadway support, under the influence of high stress and dynamic pressure, the surrounding rock of the roadway continuously moves towards the roadway floor, resulting in the uplift of the floor. And erecting a grouting cage-shaped anchor cable on the floor is an effective means to treat the floor heave of coal mine roadways. For the grouting and anchoring cage-shaped anchor cable, after the anchor solidifies, it is tensioned and pre-tightened, and then grouting is carried out in the anchor cable hole. This process can, while ensuring the anchoring force and the length of the free section of the anchor cable, spread the applied pre-tightening force to a larger range of rock masses, and finally the grouting can restore the integrity of the broken surrounding rock around the anchor cable, making the prestress spread better.

[0003] However, since the cage shape of the non-anchored section of the anchor cable is hollow and filled with impact-absorbing and energy-absorbing materials, which has the function of absorbing energy and resisting impact. In the case of good rock properties, when the anchor cable is subjected to impact load, the impact-absorbing and energy-absorbing materials in the anchor cable cage shrink and deform, storing deformation energy and playing the role of energy absorption; but when the anchor cable is arranged in broken surrounding rock, if the cage filled with energy-absorbing materials is still used, due to the shrinkage and deformation of the cage, the anchor cable cannot be bonded to the surrounding rock as a whole through the anchoring agent, and cannot effectively play the role of fixing the surrounding rock with the anchoring force, and in severe cases, the cage-shaped anchor cable fails as a whole. Content of the Utility Model

[0004] The utility model provides a cage-shaped anchor cable with a resistance increasing device, aiming at solving the problem that when the cage-shaped anchor cable is used for supporting broken surrounding rock, the anchor cable shrinks and deforms under impact load and is prone to failure.

[0005] To achieve its purpose, the utility model adopts the following technical scheme:

[0006] A cage-shaped anchor cable with a resistance increasing device, including a butterfly tray. A through hole is provided at the center of the butterfly tray, and an anchor cable passes through the through hole. The anchor cable is formed by spirally winding a plurality of steel strands. Its characteristics are that: the anchored section of the anchor cable extends out of the butterfly tray and is connected with an anchor cable anchor, the non-anchored section of the anchor cable is inserted into the surrounding rock, and a plurality of resistance increasing devices are equidistantly penetrated through the central steel strand of the non-anchored section, and a cage-shaped structure is arranged on the non-anchored section at the position of the resistance increasing device.

[0007] Further, the resistance increasing device is spindle-shaped.

[0008] Further, a connection hole is penetrated through the resistance increasing device.

[0009] Further, the inner diameter of the connection hole is larger than the outer diameter of the steel strand.

[0010] Furthermore, the spacing between adjacent resistance increasing devices is 400 - 500 mm.

[0011] Compared with the prior art, the beneficial effects of the present utility model are as follows:

[0012] When the birdcage-shaped anchor cable provided by the present utility model is arranged in the broken surrounding rock, due to the resistance increasing effect of the spindle-shaped resistance increasing device inside the birdcage, the resistance between the anchor cable and the surrounding rock is increased. At the same time, the shrinkage deformation amount of the birdcage caused by the impact of the surrounding rock is reduced, ensuring that the anchor cable is bonded to the surrounding rock as a whole through the anchoring agent, and the effective acting force of the anchor cable for anchoring the surrounding rock is fully exerted. Moreover, the spindle-shaped resistance increasing device can ensure that when the birdcage-shaped anchor cable is impacted by the surrounding rock, the stress received by each steel wire is uniform, and the practicability is strong. Description of the Drawings

[0013] Figure 1 is a schematic structural diagram of the birdcage-shaped anchor cable of the present utility model;

[0014] Figure 2 is Figure 1 the enlarged view at A in

[0015] Figure 3 is a schematic structural diagram of the resistance increasing device of the present utility model;

[0016] In the figure: 1 - anchoring section; 2 - butterfly tray; 3 - birdcage-shaped structure; 4 - non-anchoring section; 5 - resistance increasing device; 6 - anchoring agent; 7 - surrounding rock; 8 - steel strand; 9 - connection hole; 10 - anchor cable anchor. Detailed Embodiment

[0017] The present utility model will be further described below with reference to the accompanying drawings:

[0018] As Figures 1 - 3 shown, the present utility model is a birdcage-shaped anchor cable with a resistance increasing device, including a butterfly tray 2. A through hole is provided at the center of the butterfly tray 2, and a Φ21.6 mm anchor cable is passed through the through hole. The anchor cable is made by helically winding and twisting seven standard steel strands. The anchoring section 1 of the anchor cable extends out of the butterfly tray 2 and is connected with an anchor cable anchor 10. The non-anchoring section 4 of the anchor cable is inserted into the surrounding rock 7, and three spindle-shaped resistance increasing devices 5 are equidistantly arranged at intervals of 400 mm on the central steel strand 8 of the non-anchoring section 4. A domed birdcage-shaped structure 3 is provided on the non-anchoring section 4 at the position of the resistance increasing device 5. The 1 steel strand 8 at the center is twisted with the six steel strands 8 on the periphery to make a 1×7 type prestressed structural steel strand anchor cable; specifically, the outer diameter of the resistance increasing device is Φ11.4 mm, the overall length is 50 mm, and a ∅7.6 mm connection hole 9 is provided through the resistance increasing device 5. The inner diameter of the connection hole 9 is larger than the outer diameter of the steel strand 8.

[0019] During the tunneling process of mine roadways, when it is necessary to fix the broken surrounding rock 7, after drilling holes at the designated positions, anchoring agents 6 are injected into the holes. A birdcage-shaped anchor cable made of seven-strand steel strands 8 is placed into the holes. After the birdcage-shaped anchor cable is bonded to the surrounding rock through the anchoring agent 6 in the holes of the broken surrounding rock 7, the butterfly tray 2 is pressed tightly against the surface of the surrounding rock by tightening the anchor cable anchor 10. During the tightening process, the spindle-shaped resistance-increasing device 5 prevents the shrinkage of the domed birdcage structure 3, increases the resistance between the anchor cable and the surrounding rock, and at the same time alleviates the impact on the anchor cable and the surrounding rock, enabling the anchor cable to better fix the surrounding rock. Through the resistance-increasing effect of the spindle-shaped resistance-increasing device 5 inside the birdcage, the resistance between the anchor cable and the surrounding rock 7 is increased, and at the same time, the shrinkage deformation amount of the birdcage caused by the impact of the surrounding rock 7 is reduced, ensuring that the anchor cable is bonded to the surrounding rock 7 as a whole through the anchoring agent 6, and the effective acting force of the anchor cable to anchor the surrounding rock is fully exerted, extending the service life of the birdcage-shaped anchor cable.

Claims

1. A birdcage-shaped anchor cable with a resistance-increasing device, comprising a butterfly tray (2), a through hole is provided at the center of the butterfly tray (2), an anchor cable is threaded through the through hole, and the anchor cable is formed by spirally winding a plurality of steel strands (8), and is characterized in that: The anchorage section (1) of the cable bolt extends out of the butterfly-shaped tray (2) and is connected with a cable bolt anchor (10). The non-anchorage section (4) of the cable bolt is inserted into the surrounding rock (7), and a number of resistance increasing devices (5) are equidistantly arranged on the central steel strand (8) of the non-anchorage section (4). A birdcage-like structure (3) is arranged on the non-anchorage section (4) at the position of the resistance increasing device (5).

2. The birdcage-shaped anchor cable with a resistance increasing device according to claim 1, wherein: The resistance increasing device (5) is spindle-shaped.

3. The birdcage-shaped anchor cable with a resistance increasing device according to claim 2, characterized in that: A connection hole (9) is arranged through the resistance increasing device (5).

4. The birdcage-shaped anchor cable with a resistance increasing device according to claim 3, characterized in that: The inner diameter of the connection hole (9) is larger than the outer diameter of the steel strand (8).

5. A birdcage-shaped anchor cable with a resistance increasing device according to any one of claims 1-4, characterized in that: The distance between adjacent resistance increasing devices (5) is 400 - 500 mm.

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