CN210317342U - Large-inclination-angle working face soft coal seam grouting reinforcement structure - Google Patents
Large-inclination-angle working face soft coal seam grouting reinforcement structure Download PDFInfo
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- CN210317342U CN210317342U CN201921404649.4U CN201921404649U CN210317342U CN 210317342 U CN210317342 U CN 210317342U CN 201921404649 U CN201921404649 U CN 201921404649U CN 210317342 U CN210317342 U CN 210317342U
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- 239000003245 coal Substances 0.000 title claims abstract description 86
- 230000002787 reinforcement Effects 0.000 title claims abstract description 20
- 238000007569 slipcasting Methods 0.000 claims abstract description 25
- 230000003014 reinforcing effect Effects 0.000 claims description 2
- 238000005065 mining Methods 0.000 abstract description 9
- 239000002131 composite material Substances 0.000 description 3
- 230000000694 effects Effects 0.000 description 3
- 239000011435 rock Substances 0.000 description 3
- 238000010276 construction Methods 0.000 description 2
- 238000005553 drilling Methods 0.000 description 2
- 239000002002 slurry Substances 0.000 description 2
- 238000004901 spalling Methods 0.000 description 2
- 230000005641 tunneling Effects 0.000 description 2
- 239000000853 adhesive Substances 0.000 description 1
- 230000001070 adhesive effect Effects 0.000 description 1
- XAGFODPZIPBFFR-UHFFFAOYSA-N aluminium Chemical compound [Al] XAGFODPZIPBFFR-UHFFFAOYSA-N 0.000 description 1
- 229910052782 aluminium Inorganic materials 0.000 description 1
- 230000015572 biosynthetic process Effects 0.000 description 1
- 239000002775 capsule Substances 0.000 description 1
- 239000007788 liquid Substances 0.000 description 1
- 239000000463 material Substances 0.000 description 1
- 238000000034 method Methods 0.000 description 1
- 230000000737 periodic effect Effects 0.000 description 1
- 239000012779 reinforcing material Substances 0.000 description 1
- 238000000926 separation method Methods 0.000 description 1
- 239000007787 solid Substances 0.000 description 1
- 230000000087 stabilizing effect Effects 0.000 description 1
- 230000002195 synergetic effect Effects 0.000 description 1
- 239000010878 waste rock Substances 0.000 description 1
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Abstract
The utility model relates to a coal mining field discloses a structure that big inclination working face soft coal seam slip casting was consolidated. The grouting reinforcement structure comprises a return airway grouting hole and a working face grouting hole, wherein the return airway grouting hole comprises a return airway lower wall grouting hole and a return airway top plate grouting hole, the return airway lower wall grouting hole is arranged at the upper part of the return airway lower wall and deflects downwards, and the return airway top plate grouting hole is arranged at the top plate of the return airway and deflects towards the direction of the return airway lower wall; the working face top plate grouting holes are formed in the upper portion of the coal wall and incline upwards, the hole depth of the working face top plate grouting holes exceeds the plane where the working face top plate is located, and the coal wall middle grouting holes are formed in the middle of the coal wall and are arranged in the horizontal direction. The grouting reinforcement structure can enhance the overall stability of the working face and effectively reduce the caving problem of the rib caving.
Description
Technical Field
The utility model belongs to the technical field of the coal mining and specifically relates to a structure that big inclination working face soft coal seam slip casting was consolidated and is related to.
Background
The working face top plate is influenced by geological structure and mining, a high stress concentration area is formed near the coal wall, when the stress reaches the limit stress generated by the top plate cracks, the primary cracks in the top plate begin to expand, and weak face structures such as bedding, joints and the like begin to develop. Because the lithology of the top plate of the working surface is softer, the cracks are easier to develop, the adjacent cracks are communicated with each other along with the expansion of the cracks, the top plate forms a plate and block structure separated from the coal body, and the separation phenomenon is generated in the top plate along with the development of bedding. The roof breaks with further increase in tensile stress and eventually forms a fissure zone due to mining and the continued action of the upper strata and the cracks exhibit a periodic dynamic progression as mining progresses.
Taking a working face of a certain mine 11392-1 as an example, the north part of the working face is a goaf, and the east part, the south part and the west part of the working face are all undeveloped solid coal seams. The coal seam mined on the working face is a 39# coal seam, belongs to a medium-thickness coal seam, has the thickness of 1.74-3.02 m and the average thickness of 2.38m, has the mining height of 2.33-3.37 m and the average thickness of 2.85m, contains 3-4 layers of sandwiched waste rock, belongs to a coal seam with a complex structure, and has the structure of 0.15(0.13), 0.93(0.22), 1.12(0.12) and 0.18; the dip angle of the coal seam is 16-20 degrees, and the average dip angle is 18 degrees. The industrial grade of the coal bed is lean coal, the mining index is 1, the coefficient of variation is 9 percent, and the coal bed belongs to a relatively stable coal bed. The coal seam roof is a composite roof, the thickness of the composite roof is 1.0-5.6 m, and the roof is broken under the influence of geological structures. When the working face return airway is used for tunneling construction, two normal faults F1 and F2 are disclosed, wherein the fall of F1 is 6.4m at most; during the tunneling construction of the working face transportation lane, eight normal faults F3-F10 are disclosed, wherein the fall of the normal fault F4 is 8.9m at most. When a working face enters a No. 16 syncline shaft part and a fault group for mining, a local composite top plate of the working face is broken due to the influence of the syncline shaft, the fault group and a gob-side entry retaining wall body of a return airway, so that rib spalling and top leakage of a No. 30-59 support of the working face are serious, wherein top leakage of a No. 41-46 support section is serious, the depth of rib spalling of a coal wall reaches 6.0m, and the roof caving width above a support top beam reaches 6m and the height is 5.5 m.
In order to treat the caving area of the ledge, a grouting reinforcement mode can be adopted. For example, patent application with publication number CN206397515U discloses a gob-side roadway protection structure for fully mechanized coal mining face, in which a plurality of grouting holes are arranged in the direction of the section of the gob-side roadway, and a reinforced structure is formed by grouting. The utility model discloses a consolidate broken country rock bearing capacity and anti deformability behind the improvement entry through the slip casting for the gob entry can be recycled, realizes reciprocating type exploitation, and economic benefits is showing.
The grouting reinforcement mode can be applied to reinforcement of the working surface of the soft coal seam, but the concrete grouting mode of the working surface of the soft coal seam, particularly the arrangement of grouting holes, cannot be directly referred to, and the best grouting reinforcement effect cannot be achieved.
SUMMERY OF THE UTILITY MODEL
The utility model aims to solve the technical problem that a structure that big inclination working face soft coal seam slip casting was consolidated is provided, strengthens the holistic stability of working face, effectively reduces the wall caving problem.
The utility model discloses a grouting and reinforcing structure of a soft coal seam on a large-dip-angle working face, which comprises a return airway grouting hole and a working face grouting hole,
the air return lane grouting holes comprise an air return lane lower side grouting hole and an air return lane top plate grouting hole, the air return lane lower side grouting hole is formed in the upper portion of the air return lane lower side and deflects downwards, and the air return lane top plate grouting hole is formed in the top plate of the air return lane and deflects towards the direction of the air return lane lower side;
the working face top plate grouting holes are formed in the upper portion of the coal wall and incline upwards, the hole depth of the working face top plate grouting holes exceeds the plane where the working face top plate is located, and the coal wall middle grouting holes are formed in the middle of the coal wall and are arranged in the horizontal direction.
Preferably, the coal wall middle grouting holes are located on the middle line of two adjacent working face top plate grouting holes, and the two adjacent working face top plate grouting holes and the coal wall middle grouting hole between the two adjacent working face top plate grouting holes form a grouting reinforcement group.
Preferably, the height difference between the grouting holes of the working face top plate and the working face top plate is 0.3-0.8 m, and the included angle between the grouting holes of the working face top plate and the plane of the working face top plate is 10-20 degrees.
Preferably, the distance between two adjacent working face top plate grouting holes is 5-8 m, and the horizontal distance between the middle part grouting hole of the coal wall and the adjacent working face top plate grouting hole is 2.5-4 m.
Preferably, the depths of the top plate grouting hole and the middle part grouting hole of the coal wall of the working face are both 3-4 m.
Preferably, the working face grouting holes further include working face bottom plate grouting holes, and the working face bottom plate grouting holes are opened at the bottom plate close to the coal wall and are arranged in the vertical direction.
Preferably, the distance between the grouting holes of the bottom plate of the working face and the coal wall is 0.1-0.5 m, and the depth is 1-2 m.
Preferably, the working face bottom plate grouting holes and the working face top plate grouting holes above the working face bottom plate grouting holes are arranged in a one-to-one correspondence mode, and the corresponding working face bottom plate grouting holes and the corresponding working face top plate grouting holes are located on the same vertical cross section.
Preferably, the top plate grouting hole of the return airway is positioned on the side of the center line of the return airway close to the lower side of the return airway, and the horizontal distance between the top plate grouting hole of the return airway and the center line of the return airway is 0.1-0.3 m.
Preferably, the distance between the grouting holes of the lower side of the air return lane and the top plate of the air return lane is 0.1-0.2 m, the depths of the grouting holes of the lower side of the air return lane and the grouting holes of the top plate of the air return lane are both 3-4 m, the included angle between the grouting holes of the lower side of the air return lane and the horizontal plane is 10-20 degrees, and the included angle between the grouting holes of the top plate of the air return lane and the vertical direction is 10-20 degrees.
The utility model has the advantages that: the utility model discloses a reinforced (rfd) structure of slip casting according to the characteristics at the position of the easy group roof fall of working face, arranges in the preferred position of return airway and working face respectively to the deviation of control slip casting concreties coal seam and top bottom plate, improves coal seam and top bottom plate self stability, thereby reaches the purpose of working face safety stoping, reduces the grouting hole total number to a certain extent simultaneously, reduces the work load of slip casting.
Drawings
Fig. 1 is an overall plan view of the present invention;
FIG. 2 is a cross-sectional view of the return airway;
FIG. 3 is a schematic illustration of a coal wall;
fig. 4 is a cross-sectional view of the working face.
The arrows in fig. 1 indicate the direction of advance of the working surface.
Reference numerals: the grouting device comprises a return airway top plate grouting hole 1, a return airway lower wall grouting hole 2, a working face top plate grouting hole 3, a coal wall middle grouting hole 4, a working face bottom plate grouting hole 5, a return airway central line 6 and a support 7.
Detailed Description
The present invention will be further explained with reference to the accompanying drawings.
The utility model discloses a structure that big inclination working face soft coal seam slip casting was consolidated, including return air tunnel slip casting hole and working face slip casting hole, return air tunnel slip casting hole includes return air tunnel lower wall slip casting hole 2 and return air tunnel roof slip casting hole 1, return air tunnel lower wall slip casting hole 2 sets up in the upper portion of return air tunnel lower wall and incline downwards, return air tunnel roof slip casting hole 1 sets up in the roof of return air tunnel and incline towards return air tunnel lower wall direction;
as shown in fig. 3, from mechanical analysis, the rib stripping problem is more easily taken place to one side of group under the return airway, and the roof fall problem then mainly takes place in the roof region of group under being close to, consequently, the utility model discloses the top of group sets up group slip casting hole 2 under the return airway to make it move towards on the lower side, with return airway roof slip casting hole 1 towards return airway roof slip casting hole 1, the important roof region of group under group and being close to down of group under consolidating the return airway, utilize less slip casting hole can reach the effect of stabilizing the coal seam.
The working face top plate grouting holes comprise working face top plate grouting holes 3 and coal wall middle part grouting holes 4, the working face top plate grouting holes 3 are formed in the upper portion of the coal wall and are inclined upwards, the hole depth of the working face top plate grouting holes 3 exceeds the plane where the working face top plate is located, and the coal wall middle part grouting holes 4 are formed in the middle of the coal wall and are arranged in the horizontal direction.
Because the coal wall is nearer with the distance of support 7, at the direct comparatively difficult in roof drilling, for this reason, the utility model discloses set up working face roof slip casting hole 3 in coal wall upper portion, the plane at the place of working face roof is surpassed to the incline hole depth that makes progress to the realization is to the enhancement of working face roof, and coal wall middle part slip casting hole 4 is seted up to the level simultaneously, further strengthens whole coal wall intensity.
Grouting can be carried out after the grouting holes are arranged, the best grouting is a Basff grouting liquid, and the grouting process is completed according to three steps of drilling, inserting a grouting pipe, grouting a hole packer and grouting. In the initial stage of grouting, the capsule of the grouting hole packer is expanded by the grouting pressure of the equipment; when the grouting pressure exceeds a certain value, an aluminum sheet at the front end of the grouting hole packer is broken, and grouting is started; when the slurry fills the borehole, the slurry is forced into the fractures of the coal formation due to the pressure of the grouting equipment (up to about 50 MPa). After the crushed coal rock mass is pressed into the cracks, the Passion reinforcing material is quickly solidified, and the crushed coal rock mass can be quickly and completely bonded into a whole with pressure bearing capacity due to the extremely strong adhesive capacity of the material.
The coal wall middle grouting holes 4 and the working face top plate grouting holes 3 are close to the positions of the two to mutually influence each other, in order to achieve the best synergistic effect, the coal wall middle grouting holes 4 are located on the central lines of the two adjacent working face top plate grouting holes 3, the two adjacent working face top plate grouting holes 3 and the coal wall middle grouting hole 4 between the two adjacent working face top plate grouting holes form a grouting reinforcement group, wherein the two working face top plate grouting holes 3 are used for grabbing tops, one coal wall middle grouting hole 4 is used for fixing sides, the tops are grabbed and the sides are fixed together, and the strength of the coal wall is guaranteed.
Regarding the parameters of the concrete working face grouting holes, in the embodiment shown in fig. 3 and 4, the height difference between the working face top plate grouting holes 3 and the working face top plate is 0.3-0.8 m, and the included angle between the working face top plate grouting holes 3 and the plane of the working face top plate is 10-20 degrees, wherein the optimal value is 15 degrees. The distance between two adjacent working face top plate grouting holes 3 is 5-8 m, and the horizontal distance between the coal wall middle part grouting hole 4 and the adjacent working face top plate grouting hole 3 is 2.5-4 m. The depths of the working face top plate grouting holes 3 and the coal wall middle grouting holes 4 are both 3-4 m.
Except for the coal wall middle grouting holes 4 and the working face top plate grouting holes 3, the bottom plate can be further reinforced according to specific conditions, and the concrete scheme is as follows: the working face grouting holes further comprise working face bottom plate grouting holes 5, and the working face bottom plate grouting holes 5 are formed in the bottom plate close to the coal wall and are arranged in the vertical direction. Although the support 7 and the coal wall are still small on the floor, the grouting position is at the bottom, so that the operation is convenient for personnel, the limited influence is small, and the arrangement of the grouting holes 5 on the floor of the working face can be considered when necessary. In the embodiment shown in fig. 4, the distance between the grouting holes 5 of the bottom plate of the working face and the coal wall is 0.1-0.5 m, and the depth is 1-2 m. The bottom plate grouting holes 5 of the working face are also considered to be cooperated with other grouting holes, and as an optimal scheme, the bottom plate grouting holes 5 of the working face and the top plate grouting holes 3 of the working face above the bottom plate grouting holes 5 of the working face are arranged in a one-to-one correspondence mode, and the corresponding bottom plate grouting holes 5 of the working face and the top plate grouting holes 3 of the working face are located on the same vertical cross section. Therefore, the working face bottom plate grouting holes 5, the working face top plate grouting holes 3 and the coal wall middle part grouting holes 4 form quincunx arrangement, and the optimal upper fixing effect is achieved.
As shown in fig. 2, as a preferred embodiment, the return airway top plate grouting hole 1 is located on the side of the return airway central line 6 close to the lower side of the return airway, so as to better reinforce the return airway, and the horizontal distance between the return airway top plate grouting hole 1 and the return airway central line 6 is preferably 0.1-0.3 m in terms of specific parameters. The distance between the grouting holes 2 on the lower side of the air return lane and the top plate of the air return lane is 0.1-0.2 m, the depths of the grouting holes 2 on the lower side of the air return lane and the grouting holes 1 on the top plate of the air return lane are both 3-4 m, the included angle between the grouting holes 2 on the lower side of the air return lane and the horizontal plane is 10-20 degrees, and the included angle between the grouting holes 1 on the top plate of the air return lane and the vertical direction is 10-20 degrees.
Claims (10)
1. The grouting reinforcement structure for the soft coal seam on the large-inclination working face is characterized by comprising a return airway grouting hole and a working face grouting hole;
the air return lane grouting holes comprise an air return lane lower side grouting hole (2) and an air return lane top plate grouting hole (1), the air return lane lower side grouting hole (2) is formed in the upper portion of the air return lane lower side and deflects downwards, and the air return lane top plate grouting hole (1) is formed in the top plate of the air return lane and deflects towards the direction of the air return lane lower side;
the working face top plate grouting holes comprise working face top plate grouting holes (3) and coal wall middle part grouting holes (4), the working face top plate grouting holes (3) are arranged on the upper part of the coal wall and incline upwards, the hole depth of the working face top plate grouting holes (3) exceeds the plane where the working face top plate is located, and the coal wall middle part grouting holes (4) are arranged in the middle of the coal wall and are arranged along the horizontal direction.
2. The structure for grouting reinforcement of a soft coal seam on a large-dip-angle working face as claimed in claim 1, wherein: the coal wall middle grouting holes (4) are positioned on the center lines of the two adjacent working surface top plate grouting holes (3), and the two adjacent working surface top plate grouting holes (3) and the coal wall middle grouting hole (4) between the two adjacent working surface top plate grouting holes form a grouting reinforcement group.
3. The structure for grouting reinforcement of a soft coal seam on a large-dip-angle working face as claimed in claim 2, wherein: the height difference between the working face top plate grouting holes (3) and the working face top plate is 0.3-0.8 m, and the included angle between the working face top plate grouting holes (3) and the plane where the working face top plate is located is 10-20 degrees.
4. The structure for grouting reinforcement of a soft coal seam on a large-dip-angle working face as claimed in claim 2, wherein: the distance between two adjacent working face top plate grouting holes (3) is 5-8 m, and the horizontal distance between the coal wall middle grouting hole (4) and the adjacent working face top plate grouting hole (3) is 2.5-4 m.
5. The structure for grouting and reinforcing the soft coal seam of the large-inclination-angle working face as claimed in claim 1, 2, 3 or 4, wherein: the depths of the working face top plate grouting holes (3) and the coal wall middle grouting holes (4) are both 3-4 m.
6. The structure for grouting reinforcement of a soft coal seam on a large-dip-angle working face as claimed in claim 2, wherein: the working face grouting holes further comprise working face bottom plate grouting holes (5), and the working face bottom plate grouting holes (5) are formed in the positions, close to the coal wall, of the bottom plates and are arranged in the vertical direction.
7. The structure for grouting reinforcement of the soft coal seam of the large-dip-angle working face as claimed in claim 6, wherein: the distance between the grouting holes (5) of the bottom plate of the working face and the coal wall is 0.1-0.5 m, and the depth is 1-2 m.
8. The structure for grouting reinforcement of the soft coal seam of the large-dip-angle working face as claimed in claim 6, wherein: working face bottom plate slip casting hole (5) and working face roof slip casting hole (3) one-to-one above it arrange, corresponding working face bottom plate slip casting hole (5) and working face roof slip casting hole (3) are located same vertical cross-section.
9. The structure for grouting reinforcement of a soft coal seam on a large-dip-angle working face as claimed in claim 1, wherein: the air return lane top plate grouting hole (1) is located on the side, close to the lower side of the air return lane, of the air return lane central line (6), and the horizontal distance between the air return lane top plate grouting hole (1) and the air return lane central line (6) is 0.1-0.3 m.
10. The structure for grouting reinforcement of a soft coal seam on a large-dip-angle working face as claimed in claim 1, wherein: the distance between the lower side grouting holes (2) of the air return lane and the top plate of the air return lane is 0.1-0.2 m, the depths of the lower side grouting holes (2) of the air return lane and the top plate grouting holes (1) of the air return lane are 3-4 m, the included angle between the lower side grouting holes (2) of the air return lane and the horizontal plane is 10-20 degrees, and the included angle between the top plate grouting holes (1) of the air return lane and the vertical direction is 10-20 degrees.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201921404649.4U CN210317342U (en) | 2019-08-27 | 2019-08-27 | Large-inclination-angle working face soft coal seam grouting reinforcement structure |
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| Application Number | Priority Date | Filing Date | Title |
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| CN201921404649.4U CN210317342U (en) | 2019-08-27 | 2019-08-27 | Large-inclination-angle working face soft coal seam grouting reinforcement structure |
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Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN114837604A (en) * | 2022-05-25 | 2022-08-02 | 安徽理工大学 | Soft coal seam working face segmented grouting system and advanced grouting method |
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2019
- 2019-08-27 CN CN201921404649.4U patent/CN210317342U/en active Active
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN114837604A (en) * | 2022-05-25 | 2022-08-02 | 安徽理工大学 | Soft coal seam working face segmented grouting system and advanced grouting method |
| CN114837604B (en) * | 2022-05-25 | 2023-09-22 | 安徽理工大学 | Segmented grouting system and advanced grouting method for soft coal seam working face |
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Address after: 617066 Sichuan Chuanmei Huarong Energy Co., Ltd., xujiadu village, West District, Panzhihua City, Sichuan Province Patentee after: Sichuan Chuanmei Huarong Energy Co.,Ltd. Address before: 617066 Sichuan Chuanmei Huarong Energy Co., Ltd., xujiadu village, West District, Panzhihua City, Sichuan Province Patentee before: SICHUAN CHUANMEI HUARONG ENERGY CO.,LTD. |