A retaining wall structure and construction method of a lower middle section extension horse head door

Abstract

The application discloses a kind of lower middle section extension horse head door through retaining wall structure and construction method, including straight-through surface shaft and for lifting ore or personnel, material up and down operation cage, and to be constructed lower middle section, cage way is equipped in the shaft;The cage is arranged in cage way;The lower middle section to be constructed two sides are equipped with the short horse head door of constructed short horse head door;The short horse head door is installed with retaining wall, and short horse head door and retaining wall form horse head door section between retaining wall;The retaining wall includes anchor rod, column, crossbeam, angle steel, small door and shock-absorbing layer.The application is aimed at the problem that existing underground mine in expansion period lower middle section extension horse head door through causes damage to shaft production influence, by the design of retaining wall structure, so that overall strength is high, simple to make and install, process is simple, little influence to shaft production, high safety, low cost.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of mine construction and production, in particular to a retaining wall structure and construction method for a lower middle section extended horsehead door. BACKGROUND

[0002] Generally, underground mining is to construct a vertical shaft to a certain depth from the ground surface, and a horsehead door roadway is constructed at the designed position of each middle section of the vertical shaft at the same time. Then, a crosscut roadway and a transportation level roadway are constructed. In this way, the mined ore can be lifted to the ground surface from the shaft through each level.

[0003] After a certain period of time and depth of underground mining, deep ore bodies need to be mined. The primary work of capacity expansion is to complete the shaft and roadway development project of the lower middle section. During the first phase of construction of an underground mine, the vertical shaft required for the mining depth in the later period is constructed in its entirety, and the shaft is equipped for lifting the mined ore in the first phase of production.

[0004] In order to shorten the construction period of an underground mine, produce ore as soon as possible, and generate benefits, or because of the complex hydrogeological conditions of the lower part of the shaft, the horsehead door roadway required for the later mining of the shaft is not constructed or is constructed for a short time when the vertical shaft is constructed in its entirety. During the expansion, the horsehead door roadway and the transportation level roadway, which must be constructed for the later mining of the ore and are connected to the shaft at each middle section, are conventionally constructed in two ways. One way is to remove the existing shaft equipment, install drilling facilities such as a hoist platform, and then construct the horsehead door roadway and the crosscut roadway. This method inevitably causes the existing shaft to stop production, resulting in large losses for the mine, a long time, complex process conversion, high cost, and the like. The other way is to use the existing short horsehead door to construct forward, which inevitably damages the existing shaft facilities during blasting and excavation, causing intermittent shaft production, manual ore removal, complex process conversion, a long time, high safety risk, low efficiency, and poor benefits. SUMMARY

[0005] The present application aims to provide a retaining wall structure and construction method for a lower middle section extended horsehead door, which has high strength, is simple to manufacture and install, has simple processes, has a small impact on shaft production, is safe, and is low in cost, so as to solve the problem of damage and impact on shaft production caused by the extension of the horsehead door of the lower middle section during the expansion of an existing underground mine.

[0006] To achieve the above-mentioned purpose, the present application provides the following technical solutions:

[0007] The application discloses a retaining wall structure of a lower middle section extended through a horsehead door, which comprises a shaft penetrating the ground surface, a cage for lifting ores or personnel and materials up and down, and a lower middle section to be constructed, wherein the shaft is provided with a cage way, the cage is arranged in the cage way, and the lower middle section to be constructed is provided with short horsehead doors constructed on both sides.

[0008] Further, the columns are arranged and installed at intervals not greater than 1 m along the horizontal direction of the horsehead door section; the cross beams are arranged and installed from the bottom plate upwards along the vertical direction of the horsehead door section, wherein the first cross beam is 200 mm above the bottom, and the remaining cross beams are arranged and installed at intervals not greater than 1 m; the column is a full-length whole 25# I-beam, and the two ends are arranged perpendicularly to the horsehead door bottom plate and top plate respectively; the cross beam is formed by connecting a plurality of short beams at the same level, each short beam is installed between two columns, each short beam is a 25# I-beam, the length of each short beam is the net distance between two columns minus 80 mm, and an elliptical hole with a diameter not less than 22 mm and a length not less than 60 mm is arranged at the central position of the end head of each short beam; and the two wings of the I-beam of the column and the cross beam are arranged perpendicularly to the direction of the horsehead door section.

[0009] Further, the anchor rod is anchored into the surrounding rock by 1000 mm, exposed by 500 mm, and has a diameter of 36 mm, two anchor rods form a group with a spacing not greater than 100 mm, and the number is determined according to the installation position of the cross beam and the column; the two ends of the column and the cross beam are firmly welded on each group of anchor rods, and the intersection of the column and the cross beam is connected through an angle steel.

[0010] Further, the angle steel is a 10# equilateral angle steel with a length of 100 mm, one wing of the angle steel is welded to the side of the column at the intersection of the cross beam and the column, and the other wing is provided with an elliptical hole with a diameter not less than 22 mm and a length not less than 60 mm at the central position of the end head.

[0011] Further, the long elliptical hole on the one wing of the angle steel welded to the column corresponds to the long elliptical hole at the end head of the short cross beam, two 18 mm bolts with washers are used to fix the short cross beam to the side of the column, and the two short cross beams are connected to form a cross beam, and the other short cross beam is directly welded to the anchor rod near the end side of the roadway section.

[0012] Further, the shock-absorbing layer is arranged between the horsehead door face and the column and cross beam frame, and is sequentially and densely provided with sand-filled burlap bags, bamboo rows and logs.

[0013] Further, the small door is arranged at the middle of the bottom end of the retaining wall, the width of the small door is the net distance between the two upright columns in the middle, and the height of the small door is the net distance below the third cross beam; the door frame of the small door is welded by 50mm angle steel, and the face plate is welded by steel mesh with a diameter of 10mm and a spacing of 100mm.

[0014] Further, the length of the upright column, the cross beam, the sack, the bamboo and the log is determined according to the existing horse head door specification.

[0015] The application provides another technical scheme: a construction method of a retaining wall structure of a lower middle section extending horse head door, comprising the following steps:

[0016] S1: the cage is lowered to the short horse head door, and the actual coordinate values of X, Y and Z of the center of the bottom plate of the short horse head door are accurately measured; the shape of the profile line of the roadway section about 1000mm away from the working face is measured;

[0017] S2: the retaining wall frame diagram is drawn according to the measured roadway section, the upright columns and the short cross beam are processed according to the diagram, and the angle steel wing is welded to the two wings of the upright column 62 according to the design position;

[0018] S3: the cage is lowered to the short horse head door, the anchor rod position is calibrated according to the design retaining wall frame diagram at the position of the roadway section about 1000mm away from the working face, the anchor rod is drilled and installed, and the two ends of the processed upright column are welded to the anchor rod group of the top and bottom plates;

[0019] S4: the sand-filled sack, the bamboo and the log are sequentially and densely arranged between the working face of the short horse head door and the upright column frame;

[0020] S5: the short cross beam is fixed on the other wing of the connecting angle steel according to the design position between each upright column by using a bolt, and the other end of the short cross beam on the two sides of the roadway is directly welded to the anchor rod of the two sides;

[0021] S6: the small door is installed at the middle position according to the design;

[0022] S7: the inclined roadway is excavated from the existing upper middle section at a proper position to a proper position of the designed lower middle section roadway to be developed;

[0023] S8: the actual coordinate values of X, Y and Z of the center of the bottom plate of the lower middle section roadway below the inclined roadway are accurately measured;

[0024] S9: the center line direction and the waist line position of the bottom plate of the excavation to the short horse head door are calculated according to the two actual coordinate values of S1 and S8;

[0025] S10: the lower middle section roadway is excavated to the short horse head door according to the data of S9, the gangue is lifted to the upper middle section by using a winch through the inclined roadway, and then the gangue is lifted to the ground through the shaft;

[0026] S11: at a position about 15 m from the short horse head door working face, accurately measuring the X, Y and Z actual coordinate values of the center of the floor of the lower middle section roadway working face, and calculating the distance between the center of the floor of the short horse head door working face;

[0027] S12: when the actual difference of S11 is less than 15 m, the lower middle section roadway is excavated in the direction of the short horse head door in a short excavation and short support mode with a shot footage of no more than 1000 mm; when the actual difference of S11 is less than 5 m, a small pilot hole is used for excavation; before each blasting, personnel at the wellhead of each level are notified to evacuate, and the cage is stopped from running; after blasting, the cage is used to check the well wall and well facilities, and after confirming that they are intact, the cage can be used for production;

[0028] S13: after the small pilot hole is excavated through, the layer is expanded and the roof is pressed until the horse head door section is excavated through;

[0029] S14: the horse head door is supported according to the design;

[0030] S15: the retaining wall structure is removed.

[0031] Compared with the prior art, the retaining wall structure and the construction method for extending the horse head door through the lower middle section have the following beneficial effects:

[0032] 1. The retaining wall structure and the construction method for extending the horse head door through the lower middle section, the stand and the beam are processed on the ground, which is convenient and fast; the stand and the beam are connected through bolts, which is simple, can shorten the installation time underground, reduce the construction amount and construction strength, and reduce the construction cost; the stand and the beam are welded on the anchor rod in the surrounding rock, the retaining wall and the surrounding rock form an integral whole through the anchor rod, and have good shock resistance, high strength and safety and reliability.

[0033] 2. The retaining wall structure and the construction method for extending the horse head door through the lower middle section, the stand and the beam steel frame and the working face are sequentially and densely provided with sand-filled burlap bags, bamboo piles and log shock absorption layers between the working face, which has the advantages of simple structure, convenient material, fast installation, low cost and good shock absorption effect.

[0034] 3. The retaining wall structure and the construction method for extending the horse head door through the lower middle section, the inclined roadway is excavated from the upper middle section to the lower middle section, which is separate from the original short horse head door construction, safe and reliable, and when the through distance is less than 5 m, a small pilot hole is used for excavation, which is safe, has small damage to the well facilities and can ensure normal production of the mine. BRIEF DESCRIPTION OF DRAWINGS

[0035] Figure 1 It is a horse head door through construction plane schematic diagram of the application;

[0036] Figure 2 It is a horse head door through construction section schematic diagram of the application;

[0037] Figure 3The schematic diagram of the through retaining wall structure of the horse head door of the present application;

[0038] Figure 4 The schematic diagram of the column and beam joint of the present application;

[0039] Figure 5 The schematic diagram of the shock absorbing layer structure of the present application.

[0040] In the figure: 1, shaft; 2, cage; 3, shaft guide; 4, short horse head door; 5, horse head door section; 6, retaining wall; 61, anchor rod; 62, column; 63, beam; 64, angle steel; 65, small door; 66, shock absorbing layer; 7, lower middle section. DETAILED DESCRIPTION

[0041] The technical solutions in the embodiments of the present application will be clearly and completely described below with reference to the accompanying drawings in the embodiments of the present application. Obviously, the described embodiments are only part of the embodiments of the present application, rather than all the embodiments. Based on the embodiments in the present application, all other embodiments obtained by those skilled in the art without creative work fall within the scope of protection of the present application.

[0042] Please refer to Figures 1-5 The present application provides a retaining wall structure extending through the horse head door of the lower middle section, which comprises a shaft 1 extending through the ground surface, a cage 2 for lifting ore or personnel and materials to run up and down, and a lower middle section 7 to be constructed, wherein the shaft 1 is provided with a shaft guide 3; the cage 2 is arranged in the shaft guide 3; the lower middle section 7 to be constructed is provided with a short horse head door 4 constructed on both sides; the short horse head door 4 is provided with a retaining wall 6 installed on the face of the horse head door, and a horse head door section 5 is formed between the short horse head door 4 and the retaining wall 6; the retaining wall 6 comprises an anchor rod 61, a column 62, a beam 63, an angle steel 64, a small door 65 and a shock absorbing layer 66.

[0043] In the above embodiment, the columns 62 are arranged and installed at equal distances along the horizontal direction of the horse head door section 5 with a spacing not greater than 1 m; the beams 63 are arranged and installed in the vertical direction of the horse head door section 5 from the bottom plate upwards, wherein the first beam is 200 mm above the bottom, and the remaining beams are arranged and installed at equal distances with a spacing not greater than 1 m; the column 62 is a full-length whole 25# I-beam, and the two ends are arranged perpendicularly to the bottom plate and the top plate of the horse head door; the beam 63 is formed by connecting a plurality of short beams at the same level, each short beam is installed between two columns 62, each short beam is a 25# I-beam, the length of each short beam is the net distance between the two columns 62 minus 80 mm, and an elliptical hole with a diameter width not less than 22 mm and a length not less than 60 mm is arranged at the central position of each short beam 30 mm from the end; the two wings of the I-beam of the column 62 and the beam 63 are arranged perpendicularly to the direction of the horse head door section 5.

[0044] In the above embodiment, the anchor rod 61 is anchored into the surrounding rock by 1000mm, exposed by 500mm, and has a diameter of 36mm. Two anchor rods 61 form a group with a spacing of no more than 100mm, and the number of anchor rods is determined according to the installation position of the cross beam 63 and the column 62. The two ends of the column 62 and the cross beam 63 are respectively firmly welded on each group of anchor rods 61, and the intersection of the column 62 and the cross beam 63 is connected by an angle steel 64.

[0045] In the above embodiment, the angle steel 64 is a 10# equilateral angle steel with a length of 100mm. One wing of the angle steel 64 is welded to the column side at the intersection of the cross beam 63 and the column 62, and the other wing is provided with an elliptical hole with a diameter of no less than 22mm and a length of no less than 60mm at a position 30mm away from the end.

[0046] In the above embodiment, the long elliptical hole welded to one wing of the angle steel 64 on the column 62 corresponds to the long elliptical hole at the two ends of the short cross beam. The short cross beam is fixed to the column side by two 18mm diameter bolts with washers, and the two short cross beams are connected to form the cross beam 63. The other short cross beam is directly welded to the anchor rod 61 near the end side of the roadway cross section.

[0047] In the above embodiment, the shock-absorbing layer 66 is arranged between the short horsehead door 4 and the column cross beam frame. The sand-filled grass bag, bamboo and log are arranged in sequence and densely. The length and size of the column 62, the cross beam 63, the grass bag, the bamboo and the log are determined according to the existing horsehead door specifications.

[0048] In the above embodiment, a small door 65 is arranged at the middle of the bottom end of the retaining wall 6. The width of the small door 65 is the net distance between the two columns 62 in the middle, and the height is the net distance below the third cross beam. The door frame of the small door 65 is welded by a 50mm angle steel, and the panel is welded by a steel mesh with a diameter of 10mm and a spacing of 100mm.

[0049] In order to further better explain the embodiment of the present application, a construction method of a retaining wall structure extending through a lower middle section horsehead door is also provided, which comprises the following steps:

[0050] S1: ride the cage 2 to the short horsehead door 4, accurately measure the X, Y and Z actual coordinate values of the center of the short horsehead door 4, and measure the shape of the roadway cross section about 1000mm away from the working face.

[0051] S2: draw the frame diagram of the retaining wall 6 according to the measured roadway cross section, process each column 62 and short cross beam according to the diagram, and weld one wing of the angle steel 64 to the two wings of the column 62 according to the design position.

[0052] S3: ride cage 2 to the short horse head door 4, in about 1000mm away from the working face roadway section position, according to the design of retaining wall 6 frame figure calibration anchor rod 61 position, drilling installation anchor rod 61; The two ends of the column 62 are welded on the anchor rod group of the top and bottom plate;

[0053] S4: close to the short horse head door 4 and the frame between the working face and the column 62, in turn, densely set up sand bag, bamboo and logs;

[0054] S5: according to the design position between each column 62, the short beam is fixed on the other wing of the connecting angle steel 64 by bolt; The other end of the short beam on both sides of the roadway is directly welded on the anchor rod 61 of the two sides;

[0055] S6: according to the design, install the small door 65 at the middle position;

[0056] S7: open from the existing upper middle section at a proper position, excavate the inclined roadway to the designed lower middle section roadway at a proper position;

[0057] S8: accurately determine the X, Y, Z actual coordinate values of the center of the lower middle section roadway floor under the inclined roadway;

[0058] S9: according to the two actual coordinate values of S1 and S8, calculate the center line direction and floor waist line position of the lower middle section roadway excavated towards the short horse head door 4;

[0059] S10: according to the data of S9, excavate the lower middle section roadway towards the short horse head door 4, and the gangue is lifted to the upper middle section by winch and then to the ground through the shaft 1;

[0060] S11: about 15m away from the horse head door 4, accurately determine the X, Y, Z actual coordinate values of the center of the lower middle section roadway 5 floor, and calculate the distance between the center of the lower middle section roadway 5 floor and the center of the short horse head door 4 floor;

[0061] S12: when the actual difference of S11 is less than 15m, excavate the lower middle section roadway towards the short horse head door 4 by short drilling and short support with each shot less than 1000mm; When the actual difference of S11 is less than 5m, excavate by small pilot hole; Before each shot, inform the personnel at each level shaft to evacuate, and stop the operation of the cage 2; After blasting, check the shaft wall and shaft 1 facilities by riding the cage 2, and confirm that they are intact before the cage 2 can be operated for production;

[0062] S13: after the small pilot hole is excavated through, expand the side and press the roof layer by layer until the horse head door section 5 is excavated;

[0063] S14: support the horse head door according to the design;

[0064] S15: remove the retaining wall 6 structure.

[0065] The column 62 and the cross beam 63 can be processed on the ground surface, which is convenient and fast, and is connected through bolts, which is simple, can shorten the installation time in the mine, reduce the construction amount and construction strength, and reduce the construction cost; the column 62 and the cross beam 63 are welded on the anchor rod 61 in the surrounding rock, the retaining wall 6 and the surrounding rock form an integrated body through the anchor rod 61, and the retaining wall 6 has good shock resistance, high strength, and is safe and reliable; secondly, the steel frame of the column 62 and the cross beam 63 and the face-to-face between the working face are sequentially and densely provided with the sand-filled burlap bag, the bamboo row and the log shock absorption layer, which has the advantages of simple structure, convenient material, fast installation, low cost and good shock absorption effect; in addition, the present application excavates the inclined roadway from the upper middle section to the lower middle section, which is separated from the original short horse head door 4 construction, is safe and reliable, and when the through distance is less than 5m, the small pilot hole is used for excavation, which is safe, has small damage to the facilities of the shaft 1, and can ensure the normal production of the mine.

[0066] The above is only a preferred embodiment of the present application, but the protection scope of the present application is not limited thereto, any person skilled in the art can make equivalent replacement or change according to the technical scheme and the inventive concept of the present application within the technical range disclosed by the present application, which should be covered in the protection scope of the present application.

Claims

1. A retaining wall structure extending through a lower intermediate section of a horsehead gate, characterised in that: The application relates to a mine shaft (1) passing through the ground surface and a cage (2) for lifting ores or personnel, materials, etc., and a lower middle section (7) to be constructed, wherein the mine shaft (1) is provided with a cage way (3); the cage (2) is arranged in the cage way (3); the lower middle section (7) to be constructed is provided with constructed short crosscuts (4) on both sides; the short crosscuts (4) are provided with retaining walls (6) on the front face of the crosscut; the short crosscuts (4) and the retaining walls (6) form crosscut sections (5); the retaining wall (6) comprises anchor rods (61), columns (62), cross beams (63), angle steels (64), small doors (65) and shock-absorbing layers (66). The columns (62) are arranged at equal intervals along the horizontal direction of the crosscut section (5) with a spacing not greater than 1 m; the cross beams (63) are arranged from the bottom plate upwards along the vertical direction of the crosscut section (5), wherein the first cross beam is arranged at a position 200 mm above the bottom plate, and the remaining cross beams are arranged at equal intervals with a spacing not greater than 1 m; the column (62) is a full-length whole 25# I-shaped steel, and the two ends are arranged perpendicularly to the crosscut bottom plate and top plate; the cross beam (63) is formed by connecting a plurality of short beams at the same level, each short beam is arranged between two columns (62), each short beam is a 25# I-shaped steel, the length of each short beam is the net distance between the two columns (62) minus 80 mm, and an elliptical hole with a diameter width not less than 22 mm and a length not less than 60 mm is arranged at the middle position of the short beam at a distance of 30 mm from the end; the two wings of the I-shaped steel of the column (62) and the cross beam (63) are arranged perpendicularly to the direction of the crosscut section (5); the shock-absorbing layer (66) is arranged between the crosscut face of the short crosscut (4) and the column and cross beam frame, and is sequentially and densely arranged with sand-filled burlap bags, bamboo rows and logs.

2. A retaining wall structure extending through a lower section of a horse head gate as claimed in claim 1, wherein: The anchor rod (61) is anchored into the surrounding rock by 1000 mm, exposed by 500 mm and has a diameter of 36 mm; two anchor rods (61) form a group with a spacing not greater than 100 mm, and the number is determined according to the installation positions of the cross beam (63) and the column (62); the two ends of the column (62) and the cross beam (63) are firmly welded on each group of anchor rods (61), and the intersection of the column (62) and the cross beam (63) is connected through the angle steel (64).

3. A retaining wall structure extending through a lower section of a horse head gate as claimed in claim 1, wherein: The angle steel (64) is a 10# equilateral angle steel with a length of 100 mm, one wing of the angle steel (64) is welded to the column side at the intersection of the cross beam (63) and the column (62), and the other wing is provided with an elliptical hole with a diameter width not less than 22 mm and a length not less than 60 mm at the middle position at a distance of 30 mm from the end.

4. A retaining wall structure extending through a lower section of a horse head gate as claimed in claim 1, wherein: The long elliptical hole on the one wing of the angle steel (64) welded to the column (62) corresponds to the long elliptical hole at the two ends of the short cross beam, the short cross beam is fixed on the column side through two 18 mm bolts with a diameter and a gasket, the two short cross beams are connected to form the cross beam (63), and the other short cross beam is directly welded to the anchor rod (61) close to the end side of the roadway section.

5. A retaining wall structure for a through-penetrating horse-head door of a lower intermediate extension according to claim 1, characterized in that: The small door (65) is arranged at the middle of the bottom end of the retaining wall (6), the width of the small door (65) is the net distance of the two middle vertical columns (62), and the height of the small door (65) is the net distance below the third crossbeam; the door frame of the small door (65) is welded by 50mm angle steel, and the face plate is welded by the steel mesh with a diameter of 10mm and a spacing of 100mm.

6. A retaining wall structure extending through a lower section of a horse head gate as claimed in claim 1, wherein: The length of the vertical column (62), the crossbeam (63), the sack bag, the bamboo row and the log is determined according to the existing horse head door specification.

7. A construction method of a retaining wall structure extending through a lower intermediate section of a horse head door according to claim 1, characterized in that: The method comprises the following steps: S1: the cage (2) is lowered to the short horse head door (4), the actual coordinate values of the X, Y and Z of the center of the bottom plate of the short horse head door (4) are accurately measured, and the shape of the profile line of the roadway section about 1000mm away from the working face is measured; S2: the frame drawing of the retaining wall (6) is drawn according to the actually measured roadway section, each vertical column (62) and the short crossbeam are processed according to the drawing, and the one wing of the angle steel (64) is welded to the two wings of the vertical column (62) according to the design position; S3: the cage (2) is lowered to the short horse head door (4), the position of the anchor rod (61) is calibrated according to the design frame drawing of the retaining wall (6) at the position of the roadway section about 1000mm away from the working face, the anchor rod (61) is installed by drilling, and the two ends of the processed vertical column (62) are welded to the anchor rod group of the roof and floor; S4: the sack bag, the bamboo row and the log filled with sand are arranged in sequence and densely between the working face of the short horse head door (4) and the frame of the vertical column (62); S5: the short crossbeam is fixed on the other wing of the connecting angle steel (64) by bolts according to the design position between each vertical column (62), and the other end of the short crossbeam on the two sides of the roadway is directly welded to the anchor rod (61) of the two sides; S6: the small door (65) is installed at the middle position according to the design; S7: an opening is formed at a proper position of the existing upper and middle sections, the inclined roadway is excavated to a proper position of the designed lower and middle section roadway to be developed; S8: the actual coordinate values of the X, Y and Z of the center of the floor of the lower and middle section roadway are accurately measured; S9: the center line direction and the floor waist line position of the excavation in the direction of the short horse head door (4) are calculated according to the actual coordinate values of S1 and S8; S10: the lower and middle section roadway is excavated in the direction of the short horse head door (4) according to the data of S9, the gangue is lifted to the upper and middle section by the winch through the inclined roadway, and then the gangue is lifted to the ground through the shaft (1); S11: the actual coordinate values of the X, Y and Z of the center of the floor of the working face of the lower and middle section roadway are accurately measured at the position 15m away from the working face of the horse head door (4), and the distance between the center of the floor of the working face of the lower and middle section roadway and the center of the floor of the working face of the short horse head door (4) is calculated; S12: when the actual difference of S11 is less than 15m, the lower and middle section roadway is excavated in the direction of the short horse head door (4) by the short excavation and short support method with the footage of each shot being not more than 1000mm; when the actual difference of S11 is less than 5m, the small pilot hole is excavated; the personnel at the shaft mouth of each level is informed to evacuate before each shot, and the cage (2) is stopped from running; after blasting, the cage (2) is used to check the shaft wall and the facilities of the shaft (1), and the cage (2) can be used for production only after it is confirmed that the shaft wall and the facilities of the shaft (1) are intact; S13: after the small pilot hole is excavated through, the sides are expanded and the roof is pressed in layers until the horse head door section (5) is excavated; S14: the support of the horse head door is performed according to the design. S15: dismantle the retaining wall (6) structure.

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