M-TYPE ENERGY-ABSORBING ROCKBOLT

Abstract

An M-type energy-absorbing rockbolt includes an anchorage structure, wherein two ends of the anchorage structure are respectively provided with a mixing blade and a threaded fastening section; a nut is screwed to the threaded fastening section; a plate is mounted at one end, which is close to the threaded fastening section, of the anchorage structure in a sleeving manner; one side of the plate abuts against the nut; the anchorage structure consists of first anchorage structure parts and second anchorage structure parts, wherein the second anchorage structure parts are arranged between two first anchorage structure parts; each of the second anchorage structure parts adopts an elliptical rod-shaped structure; a plurality of inwardly-concave arc-shaped grooves are formed in an outer wall of the second anchorage structure part in an axial direction, and a reinforcing rib is convexly formed at an intersection of two adjacent arc-shaped grooves.

Claims

1. An M-type energy-absorbing rockbolt comprising an anchorage structure, wherein one end of the anchorage structure is provided with a mixing blade, and the other end is provided with a threaded fastening section; a nut is screwed to the threaded fastening section; a plate is mounted at one end, which is close to the threaded fastening section, of the anchorage structure in a sleeving manner; one side of the plate abuts against the nut, and the plate is limited by the nut; theanchorage structure consists of first anchorage structure parts and second anchorage structure parts; the second anchorage structure parts are arranged between two first anchorage structure parts; each of the second anchorage structure parts adopts an elliptical rod-shaped structure; a plurality of inwardly-concave arc-shaped grooves are formed in an outer wall of the second anchorage structure part in an axial direction, and a reinforcing rib is convexly formed at an intersection of two adjacent arc-shaped grooves, so that a section of the second anchorage structure part is in a shape of polygon; and each of vertices of the polygon is rounded, and each of edges of the polygon is inwardly concave to form an arc surface.

2. The M-type energy-absorbing rockbolt according to claim 1, wherein the section of the second anchorage structure part is in a shape of quadrangle and the second anchorage structure part consists of two buckled M shapes.

3. The M-type energy-absorbing rockbolt according to claim 1, wherein the anchorage structure adopts an integrally formed structure.

4. The M-type energy-absorbing rockbolt according to claim 1, wherein the plate is circular or rectangular in a cross section; a bowl-shaped hole is formed in a center of the plate, the plate is mounted on the anchorage structure in a sleeving manner through the bowl-shaped hole, and one end, which is close to the nut, of the bowl-shaped hole extends toward an outside of the plate to form a bowl-shaped part.

5. The M-type energy-absorbing rockbolt according to claim 1, wherein a damping shim is mounted between the nut and the plate, with a thickness of 1-3 mm.

6. The M-type energy-absorbing rockbolt according to claim 1, wherein one end, which is far away from the anchorage structure, of the mixing blade, extends axially to form a boss, and an area of a cross section of the boss is less than that of a cross section of the anchorage structure.

7. The M-type energy-absorbing rockbolt according to claim 6, wherein an outer wall of the boss is concave toward an inside of the boss to form an arc surface.

8. The M-type energy-absorbing rockbolt according to claim 6, wherein a cross section of the boss is in a shape of rectangle or triangle.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

[0023] FIG. 1 is a schematic structural diagram of an M-type energy-absorbing rockbolt of the present invention;

[0024] FIG. 2 is an enlarged schematic diagram of I in FIG. 1;

[0025] FIG. 3 is a schematic structural diagram of a second anchorage structure part;

[0026] FIG. 4 is a schematic cross sectional view taken along line A-A in FIG. 3;

[0027] FIG. 5 is a schematic structural diagram of a plate;

[0028] FIG. 6 is a rear view of FIG. 5;

[0029] FIG. 7 is a schematic structural diagram of a nut with a spacer;

[0030] FIG. 8 is a rear view of FIG. 7; and

[0031] FIG. 9 is a left view of FIG. 2.

[0032] In the drawings, 1 indicates anchorage structure, 11 indicates first anchorage structure part, 12 indicates second anchorage structure part, 2 indicates mixing blade, 3 indicates threaded fastening section, 4 indicates nut, 5 indicates damping shim, 6 indicates plate, 7 indicates bowl-shaped hole, 8 indicates bowl-shaped part, and 9 indicates boss.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT

[0033] The technical schemes in the embodiments of the present invention are clearly and completely described below with reference to the accompanying drawings in the embodiments of the present invention. Apparently, the embodiments described are merely a part rather than all of the embodiments of the present invention. All other embodiments obtained by those of ordinary skilled in the art without any creative efforts based on the embodiments of the present invention shall fall within the scope of protection of the present invention.

[0034] As a note, all directional indications (such as upper, lower, left, right, front, rear, . . . ) in the embodiments of the present invention are only used for explaining the relative positional relationship, the movement among components and the like in a specific posture (as shown in the drawings). If the specific posture is changed, the directional indication also changes accordingly.

[0035] In addition, the descriptions of first, second and the like in the present invention are only used for the purpose of description and cannot be interpreted as indicating or implying relative importance or implicitly indicating the number of technical characteristics indicated. Therefore, the characteristics defined by first or second can include at least one of the characteristics explicitly or implicitly. In addition, the technical schemes of the embodiments can be combined with each other based on the realization by those of ordinary skilled in the art. When the combination of the technical schemes is contradictory or impossible to realize, the combination of the technical schemes should be considered inexistent and is not covered in the scope of protection required by the present invention.

[0036] As shown in FIG. 1 to FIG. 8, an M-type energy-absorbing rockbolt provided by the present invention comprises an anchorage structure 1 with the diameter of 16 mm-40 mm and the total length of 1200-4000 mm, and the length of the anchorage structure can be increased or decreased according to the mine ground pressure; one end of the anchorage structure 1 is provided with a mixing blade 2, and the other end is provided with a threaded fastening section 3, wherein a nut 4 is screwed to the threaded fastening section 3, and the nut 4 is 30 mm long and is made of low carbon steel; a plate 6 is mounted at one end, which is close to the threaded fastening section 3, of the anchorage structure 1 in a sleeving manner; one side of the plate 6 abuts against the nut 4, and the plate 6 is limited by the nut 4; the anchorage structure 1 consists of first anchorage structure parts 11 and second anchorage structure parts 12; when being stamped, the anchorage structure 1 is integrally formed by the first anchorage structure parts 11 and the second anchorage structure parts 12; the second anchorage structure parts 12 are arranged between two first anchorage structure parts 11; each of the second anchorage structure parts 12 adopts an elliptical rod-shaped structure, of which the left side and the right side adopt asymmetric structures, and distances from the two ends to the highest point of an arc surface of the elliptical rod-shaped structure are different; a plurality of inwardly-concave arc-shaped grooves are formed in the outer wall of the second anchorage structure part 12 in the axial direction, and a reinforcing rib is convexly formed at the intersection of two adjacent arc-shaped grooves, so that the section of the second anchorage structure part 12 is in the shape of polygon; each of the vertices of the polygon is rounded, and each of the edges is inwardly concave to form an arc surface; and a damping shim 5 is further arranged between the nut 4 and the plate 6, and the thickness of the damping shim 5 is 0.5-1 mm.

[0037] Further, in one of the embodiments, the section of the second anchorage structure part 12 is in the shape of quadrangle and the second anchorage structure part 12 consists of two buckled M shapes; each of the vertices of the quadrangle is rounded, each of the edges is inwardly concave to form an arc surface, and the radians of the arc surfaces are uniform. In other embodiments, the section of each of the second anchorage structure parts 12 can adopt any polygonal structure.

[0038] Further, the plate 6 is circular or rectangular in cross section, with a diameter of 150 mm or an overall dimension of 150 mm*150 mm and a thickness of 5-10 mm; a bowl-shaped hole 7 is formed in the center of the plate 6, the plate 6 is mounted on the anchorage structure 1 in a sleeving manner through the bowl-shaped hole 7, and one end, which is close to the nut 4, of the bowl-shaped hole 7, extends toward the outside of the plate 6 to form a bowl-shaped part 8; and the diameter of the bowl-shaped hole 7 is determined according to the diameter of the rockbolt. If the stress of the surrounding rock is large, the diameter of the plate 6 can be 200 mm or the overall dimensions can be 200 mm*200 mm and the thickness can be 10 mm. The plate 6 is made of low carbon steel by stamping.

[0039] Further, the mixing blade 2 is made of round steel by turning, with the length of 50 mm-100 mm and the thickness of 5 mm-15 mm; one end, which is far away from the anchorage structure 1, of the mixing blade 2, extends axially to form a boss 9, and the area of the cross section of the boss 9 is less than that of the cross section of the anchorage structure 1; the outer wall of the boss 9 is concave toward the inside of the boss 9 to form an arc surface; the cross section of the boss 9 is in the shape of rectangle or triangle; when the cross section of the boss 9 is in the shape of rectangle, the radians of two opposite arc surfaces of the rectangle are the same, and the radians of two adjacent arc surfaces are different, so that the boss 9 adopts a flat structure.

[0040] According to the M-type energy-absorbing rockbolt provided by the present invention, the full word of M is mace, which refers to a mace type rockbolt, wherein each of the second anchorage structure parts 12 appears as a structure formed by buckling double M; the size and the design position of the mixing blade 2 arranged at the end of the anchorage structure 1 and the second anchorage structure parts 12 arranged in the center are designed and adjusted according to the dynamic response characteristics of the rock mass; the anchoring length is the full length, and the anchoring range is between 1.5 m and 3 m; the anchoring material is resin or cement; the length of each of the second anchorage structure parts 12 can be determined according to the actual ground pressure on the site, and adjusted according to the anchoring force and the dynamic response requirements of the rock mass. Each of the second anchorage structure parts 12 not only can realize anchoring at multiple points, but also can absorb energy through tensile or shear deformation between two anchors, and besides, the kinetic energy can be absorbed through the overall sliding of the anchorage structure under the action of dynamic impact.

[0041] During the mounting of the rockbolt, the mixing blade 2 uniformly disperses resin or cement around the rockbolt in the borehole, so that the anchorage structure 1 is anchored with the surrounding rock through the uniform resin. The plate 6, the damping shim 5 and the nut 4 are mounted at the end of the anchorage structure 1, so that the rockbolt is further fixed to the surface of the surrounding rock. Under the action of static ground pressure, the mechanism of action of the energy-absorbing rockbolt is the same as that of a common rockbolt. In case of large deformation caused by high stress or dynamic damage caused by rockburst, a damping module acts to cause the damping module to rapidly slide from the resin anchoring agent, and therefore the energy accumulated in the surrounding rock is absorbed. Under the action of high stress, rockburst and brittle-ductile large deformation, the rockbolt can also stay in the resin to play a static anchoring role. That is to say, the rockbolt can be consistent with the deformation of the surrounding rock of the roadway, so that the strain performance of the surrounding rock can be absorbed and the stability of the roadway can be maintained.

[0042] To sum up, by designing the rockbolts of different types and different lengths, large deformation and strong rockburst of the surrounding rock of the roadway can be resisted; and the stability of the roadway can be realized, and the potential safety hazard caused by large deformation and rockburst of deep mines can be eliminated.

[0043] Finally, it should be noted that the above embodiments are only used for illustrating the technical scheme of the present invention, but the present invention is not limited thereto. Although the present invention is described in details with reference to the above embodiments, those of ordinary skilled in the art should understand that the embodiments of the present invention can be modified or substituted. Any modifications or equivalent substitutions without departing from the spirit and scope of the present invention should be covered in the scope of claims.