Pre-controlled top small segment filling mining method

Abstract

The present invention relates to mining, and discloses a pre-controlled top small segment filling mining method, including S1, arranging and dividing the stope along the direction of the ore body, and dividing the small segments along the height direction of the stope; S2, arranging the mining and cutting engineering for the stope; S3, arranging multiple rows of vein anchor cables near the boundary of the upper plate of the ore body to reinforce and support the upper plate surrounding rock of each small segment, and the plane where the vein anchor cables in the same row are located is perpendicular to the cross section of the ore body; arranging multiple rows of rock drilling anchor cables along the direction of the ore body to reinforce the top plate of the small segment, and the plane where the rock drilling anchor cables in the same row are located is parallel to the cross section of the ore body; S4, mining the small segment, and performing filling operation after mining is completed; S5, repeating steps S3 and S4 in sequence until the mining of the middle segment is completed. The mining method can improve the production capacity of the stope, reduce the dilution loss, and has a simple process and high safety.

Description

Technical Field

[0001] The invention relates to mining, in particular to a pre-controlled top small-segment filling mining method. Background Art

[0002] In the field of metal mineral mining, steeply inclined, extremely broken, medium-thick ore bodies are common ore bodies. The surrounding rock of the upper plate is broken and unstable, and the roof is also unstable, so the mining safety is low. It has always been a difficult problem for steeply inclined, extremely broken, medium-thick ore bodies with complex mining conditions. At present, the traditional mining methods for the mining of such ore bodies mainly include the upward layered filling method, the upward approach filling mining method, the downward approach filling mining method, etc. However, these mining methods have their own advantages and disadvantages. For some ore bodies in special environments, the single traditional upward approach filling mining method, the downward approach filling mining method, and the upward horizontal layered filling method also have some disadvantages, such as small production capacity, complex process, high mining cost, etc. Therefore, the single upward approach filling method or the downward approach filling method and the upward layered filling method are difficult to adapt to the mining of such ore bodies.

[0003] The existing patent technology CN 110566255 B discloses a design and construction method for grouting long anchor cables in the upper plate of the mine room method in the stage of segmented rock drilling, and has developed a mine room method for grouting long anchor cables in the upper plate to support the stage of segmented rock drilling. This method arranges a long anchor cable measure tunnel in the upper plate of the ore body, and constructs grouting long anchor cables in the broken zone area through the long anchor cable measure tunnel to maintain the stability of the upper plate broken zone during the ore body mining process. It mainly uses upward and downward grouting long anchor cables for support, but this method requires the construction of two measure tunnels in the surrounding rock of the upper plate. Although it has an effect on the stability of the upper plate broken zone, the newly added tunnel excavation project is large and the excavation cost is high, which is easy to cause the loss of economic benefits of the mine. In addition, the anchor cable support volume is large, the construction period is long and the difficulty is high, which will also increase the support cost. In the actual production process, it is difficult to ensure the safety of the mine.

[0004] The existing patent technology CN 112664194 A discloses a method for overall reinforcement of the upper plate broken surrounding rock with long anchor cables, which is to excavate the upper plate surrounding rock broken zone along the rock drilling cross tunnel or chamber at the bottom of each segmented ore body, and to excavate the outer vein tunnel, and to pull it to both sides to form the outer vein chamber, and then to control the top of the outer vein chamber, and in the outer vein chamber, drill the anchor cable holes row by row downward along the ore body and install the long anchor cable, so as to achieve the effect of reinforcing the upper plate broken surrounding rock. However, this method also has the problem that the excavation work of the newly added outer vein chamber is large and the excavation cost is high, which is easy to cause the loss of economic benefits of the mine.

[0005] The existing patent technology CN 113464146 A discloses a method for overall pre-support of a long anchor cable in a broken upper plate ore body. This method excavates a vein tunnel and an anchor cable fixed tunnel in the upper plate surrounding rock along the rock tunnel under the segmented ore body, arranges steel beams in the anchor cable fixed tunnel, drills parallel and spaced anchor cable holes in the ore body along the edge of the inclined ore body, arranges long anchor cables through the anchor cable holes, and fixes the long anchor cables on the steel beams at the ends. The broken upper plate surrounding rock is reinforced by the long anchor cables to improve the overall stability of the mining area. This method requires the excavation of vein tunnels and anchor cable fixed tunnels in the upper plate surrounding rock. There are also problems such as large excavation engineering volume and high excavation cost of the newly added vein tunnels and anchor cable fixed tunnels, which can easily cause economic benefits losses in the mine.

[0006] Therefore, it is necessary to design a new type of pre-controlled top small-segment filling mining method. Summary of the invention

[0007] The technical problem to be solved by the present invention is to provide a pre-controlled top small segment filling mining method, which can improve the production capacity of the mining field, reduce the dilution loss, and has a simple process and high safety.

[0008] In order to achieve the above technical problem, the present invention provides a pre-controlled top small-segment filling mining method, comprising the following steps:

[0009] S1. Arrange and divide the stope along the strike of the ore body, and divide the stope into small sections along the height direction;

[0010] S2, arranging the mining and cutting works for the stope;

[0011] S3, arranging multiple rows of vein-penetrating anchor cables near the boundary of the upper plate of the ore body to reinforce and support the surrounding rock and the top plate of the upper plate of each of the small segments, and the plane where the vein-penetrating anchor cables in the same row are located is perpendicular to the cross section of the ore body; arranging multiple rows of rock-drilling anchor cables along the direction of the ore body to reinforce the top plate of the small segments, and the plane where the rock-drilling anchor cables in the same row are located is parallel to the cross section of the ore body;

[0012] S4, mining the small segments, and performing filling operations after mining is completed;

[0013] S5. Repeat steps S3 and S4 in sequence until the mining of the stope is completed.

[0014] Preferably, in step S1, the width of the mining area is 40-50m, the height of the mining area is 50-60m, and one mining area is divided into 4-5 small sections, the height of each small section is 8-9m, and each small section is provided with a pre-controlled top of 3-4m.

[0015] Preferably, in step S2, rock drilling tunnels, segmented horizontal tunnels, chutes, chute connecting tunnels, vein tunnels, cutting shafts, cutting cross tunnels and middle transport tunnels are arranged to carry out the mining and cutting project, wherein the net cross-sectional specifications of the rock drilling tunnels, segmented horizontal tunnels, vein tunnels and chute connecting tunnels are 9 to 12 m2, the cutting shaft is 4 m2, the cutting cross tunnel is 6 m2, and the chute is 9 m2.

[0016] Specifically, a plurality of rows of blast holes are arranged downward from the bottom of the rock drilling tunnel, the blast holes in the same row are arranged in a fan shape, and the diameter of the blast holes is 76 mm, the row spacing between the blast holes is 1.8 m to 2.0 m, the hole bottom distance of the blast holes is 1.8 to 2.0 m, and the blast holes in each row are staggered.

[0017] Preferably, in step S3, several rows of the vein-penetrating anchor cables are arranged from outside the vein to inside the vein.

[0018] Preferably, in step S3, the safety net of the rock bolt is calculated by the formula: Calculation is performed, where D is the safety net, k is the unevenness coefficient, f is the Proctor coefficient, R is the breaking force, a is the width of the rock drilling tunnel, r is the weight of the ore rock, and m is the safety factor.

[0019] Preferably, in step S3, the design length of the rock bolt is calculated by the formula: L = L a +L b +L c +L d Calculate, where L is the design length of the rock drilling bolt, L a is the length of the rock bolt that needs to be exposed, L b is the thickness of the anchor, tray and metal mesh, L c is the thickness of the unstable rock layer that needs to be suspended, L d It is the anchoring length of the rock bolt penetrating into the stable rock formation.

[0020] Preferably, in step S4, the filling operation is carried out in stages, and the strength of the filling body in the middle of the filling area is lower than the strength of the filling body at the top.

[0021] Preferably, in step S5, the mining method for each of the small segments is to mine one by one from bottom to top along the mining area height, and after each small segment is mined, the filling operation is performed on it, and after the filling operation is completed, the next small segment is mined.

[0022] Preferably, the mining method for each stope is to mine in alternate locations along the direction of the ore body.

[0023] Through the above technical solution, the beneficial effects of the present invention are as follows:

[0024] The invention provides a pre-controlled top small-segment filling mining method, which is suitable for mining broken medium-thick ore bodies in areas where the ore body is steeply inclined, the upper wall surrounding rock and the stope roof are broken and unstable, and engineering geological disasters are easily caused locally. The main construction steps are as follows: first, the stope is arranged and divided along the direction of the ore body, and the small sections are divided along the height direction of the stope; then, the mining and cutting engineering is arranged for the stope; then, multiple rows of vein-penetrating anchor cables are arranged at the boundary near the upper wall of the ore body to reinforce and support the upper wall surrounding rock and the roof of each small section, and the plane where the vein-penetrating anchor cables in the same row are located is perpendicular to the cross section of the ore body; multiple rows of rock drilling anchor cables are arranged along the direction of the ore body to reinforce the roof of the small section, and the plane where the rock drilling anchor cables in the same row are located is parallel to the cross section of the ore body; then, the small section is mined, and filling operations are performed after the mining is completed; then, the remaining small sections are mined in turn until the mining of the stope is completed; finally, the remaining stopes are mined until the mining of the ore body is completed. The mining method provided by the present invention has the characteristics of large production capacity, low dilution loss rate and high safety, and the process is simple and can ensure the safety of mining.

[0025] Other features and advantages of the present invention will be described in detail in the following detailed description. BRIEF DESCRIPTION OF THE DRAWINGS

[0026] The accompanying drawings are used to provide a further understanding of the present invention and constitute a part of the specification. Together with the following specific embodiments, they are used to explain the present invention but do not constitute a limitation of the present invention. In the accompanying drawings:

[0027] Figure 1 It is a structural schematic diagram of a specific implementation method of a pre-controlled top small-segment filling mining method of the present invention;

[0028] Figure 2 yes Figure 1 Cross-sectional view in the AA direction;

[0029] Figure 3 yes Figure 1 Cross-sectional view in the BB direction;

[0030] Figure 4 yes Figure 1 The cross-sectional view in CC direction;

[0031] Figure 5 yes Figure 3 Cross-sectional view in DD direction;

[0032] Figure 6 It is a vein anchor cable support arrangement diagram of a pre-controlled top small segment filling mining method of the present invention;

[0033] Figure 7 It is a rock drilling and anchor cable support arrangement diagram of a pre-controlled top small-segment filling mining method of the present invention;

[0034] Figure 8 It is a construction schematic diagram of a rock drilling anchor cable in a pre-controlled top small-segment filling mining method of the present invention;

[0035] Fig. 9 It is a long anchor cable construction process flow chart of a pre-controlled top small segment filling mining method of the present invention;

[0036] Fig.10 It is a construction step diagram of a pre-controlled top small-segment filling mining method of the present invention.

[0037] Description of Reference Numerals

[0038] 1 Middle transport tunnel 2 Sectional level tunnel

[0039] 3 rock drilling tunnel 4 chute

[0040] 5 blastholes 6 caving ore

[0041] 7 Filling area 8 Through-vein tunnel

[0042] 9 Vein anchor cable 10 Rock drilling anchor cable

[0043] 11 Exhaust pipe 12 Cement slurry

[0044] 13 Grouting pipe 14 Hole plug DETAILED DESCRIPTION

[0045] The specific embodiments of the present invention are described in detail below in conjunction with the accompanying drawings. It should be understood that the specific embodiments described herein are only used to illustrate and explain the present invention, and the protection scope of the present invention is not limited to the following specific embodiments.

[0046] In the description of the present invention, it should be noted that, unless otherwise clearly specified and limited, the terms "set", "provided with", "installed", "matched", "connected", and "arranged" should be understood in a broad sense. For example, the connection can be a direct connection or an indirect connection through an intermediate medium, a fixed connection, a detachable connection, or an integral connection; it can be a direct connection or an indirect connection through an intermediate connector, and it can be the internal connection of two elements or the interaction relationship between two elements. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0047] In the present invention, unless otherwise specified, the directional words used, such as "inside" and "outside", are defined based on the inside and outside of the corresponding parts. In addition, "upper" and "lower" are defined based on the layout direction of each tunnel in the ore body. Specifically, in the drawings provided by the present invention, the orientation or position relationship used is based on the orientation or position relationship shown in the drawings, which is only for the convenience of describing the present invention and simplifying the description, and does not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation. Therefore, it cannot be understood as a limitation on the present invention. The orientation terms of the present invention should be understood in conjunction with the actual installation status.

[0048] See also Figure 1 and Fig.10 The present invention provides a pre-controlled top small-segment filling mining method, which is mainly aimed at steeply inclined broken medium-thick ore bodies. The upper surrounding rock of this ore body is a broken and unstable rock mass, and the roof is also unstable. During mining, the safety is low and the work efficiency is also low. The mining method provided by the present invention can avoid the occurrence of such problems. The specific steps of the method include: a first step, arranging and dividing the mining area along the direction of the ore body, and then dividing the mining area along the height direction into several small sections; a second step, arranging the mining and cutting engineering for the middle section that needs to be mined; a third step, mainly reinforcing the upper wall surrounding rock of the broken and unstable rock mass in the ore body, reinforcing the top plate of each small section, using vein-penetrating anchor cables 9, setting multiple rows of vein-penetrating anchor cables 9 near the boundary of the upper wall of the ore body, and the plane where the vein-penetrating anchor cables 9 in the same row are located is perpendicular to the cross section of the ore body, using rock drilling anchor cables 10 to reinforce the top plate of each small section, and setting multiple rows of rock drilling anchor cables 10 on the top plate of each small section along the direction of the ore body, and the plane where the rock drilling anchor cables 10 in the same row are located is parallel to the cross section of the ore body; a fourth step, mining the small section after reinforcement, and filling the small section after mining is completed; a fifth step, repeating the third and fourth steps in sequence until the mining of the middle section is completed.

[0049] It should be noted that the arrangement of the vein anchor cable 9 and the rock anchor cable 10 in the above mining method can be as follows: Figure 1 , Figure 2 , Figure 6 and Figure 7 As shown, the vein-penetrating anchor cables 9 or the rock-drilling anchor cables 10 in the same row can be arranged in a fan-shaped structure. Figure 1Taking the vein-penetrating anchor cable 9 in the example, it spreads outward from the position close to the vein to the position far from the vein to form a fan-shaped structure. Such a design can make the force of each vein-penetrating anchor cable 9 more uniform, making the vein-penetrating anchor cable 9 more effective in reinforcing the surrounding rock of the upper wall of each small segment. In addition, the "cross-section of the ore body" mentioned in the above mining method refers to the cross-section from top to bottom along the height direction of the ore body, which is perpendicular to the length direction of the ore body, such as Figure 2 As shown, Figure 2 This is a cross-sectional view of the ore body.

[0050] It should also be noted that the specific number of rows of the vein-penetrating anchor cables 9 and the rock-drilling anchor cables 10 can be adjusted according to the specific use environment and the range of the area to be reinforced. Figure 1 , Figure 2 , Figure 5 All of them are specific implementations of the present invention. In addition, the thickness of the steeply inclined broken medium-thick ore body mentioned in the above technical solution is 4 to 10 meters, and the inclination angle of the ore body is greater than 55°. Moreover, although the above technical solution is mainly aimed at steeply inclined broken medium-thick ore bodies, it can also be applied to other types of ore body structures.

[0051] The pre-controlled top small segment filling mining method can not only provide safety during the mining process and ensure the safety of personnel, but also further improve the mining efficiency and solve the problem that the steeply inclined broken medium-thick ore body is difficult to mine. In addition, by using this method to mine the ore body, the vein-piercing anchor cable 9 and the rock drilling anchor cable 10 are used to support and fix the upper wall surrounding rock and the pre-controlled top respectively, which not only improves the overall recovery rate of the mining field and reduces the ore loss rate, but also enables the use of mechanized rock drilling and ore dropping in the mining field, further improving the rock drilling efficiency of the entire mining field.

[0052] As a specific implementation of the present invention, the stope in the first step can be divided into a stope with a width of 40 to 50 m and a height of 50 to 60 m, and a stope can be divided into 4 to 5 small sections, each of which has a height of 8 to 9 m, and a 3 to 4 m pre-controlled top can be set inside each small section. This division method can divide the ore body more evenly, optimize the structural parameters for the stope and the division of small sections, and will not cause problems such as landslides due to uneven force during mining.

[0053] See also Figure 1 and Figure 2, using the method of the present invention for mining, the mining and cutting project arranged in step S2 can be carried out by arranging rock drilling tunnels 3, segmented horizontal tunnels 2, chute 4, chute connecting tunnels, vein tunnels 8, cutting skylights, cutting cross tunnels and middle transport tunnels 1, wherein the net cross-sectional specifications of the rock drilling tunnels 3, segmented horizontal tunnels 2, vein tunnels and chute connecting tunnels can be 9-12㎡, the cutting skylight specifications can be 4㎡, the cutting cross tunnel specifications can be 6㎡, and the chute 4 specifications can be 9㎡. There is no need to excavate new vein tunnels and chambers, which not only reduces the excavation workload and saves construction costs, but also ensures the safety of the mining site.

[0054] See also Figure 2 and Figure 5 , a plurality of rows of blast holes 5 are arranged downward at the bottom of the rock drilling tunnel 3, and the blast holes 5 in the same row are arranged in a fan shape. Specifically, Figure 2 As shown in FIG, the fan-shaped structure spreads downward from the bottom of the rock drilling tunnel 3, and the diameter of the blasthole 5 is 76 cm, the spacing between each row of blastholes 5 is 1.8 to 2.0 m, and the distance between the bottoms of the blastholes 5 is 1.8 to 2.0 m. The present invention adopts medium-deep hole mining, which can improve the overall safety of the mining field and the comprehensive production capacity of the entire mining field, speed up production efficiency, and shorten the operation cycle time of the mining field.

[0055] For details, see Figure 1 The preferred arrangement of the vein-penetrating anchor cables 9 is to set several rows of vein-penetrating anchor cables 9 from the outside of the vein to the inside of the vein. The vein-penetrating anchor cables 9 can reinforce the upper wall surrounding rock of each small segment, and can avoid the danger of mining difficulties or landslides during mining due to the instability of the upper wall surrounding rock.

[0056] In the third step, the safety net for the rock bolt 10 can be provided by: Calculation is performed, where D is the safety net, k is the unevenness coefficient, f is the Proctor coefficient, R is the breaking force, a is the width of the rock drilling tunnel 3, r is the weight of the ore rock, and m is the safety factor.

[0057] The design length of the rock bolt 10 can be obtained by: L = L a +L b +L c +L d Calculation is performed, where L is the design length of the rock bolt 10, L a The length of the rock bolt 10 that needs to be exposed, L b is the thickness of the anchor, tray and metal mesh, L c is the thickness of the unstable rock layer that needs to be suspended, L d It is the anchoring length of the rock bolt 10 that penetrates into the stable rock formation.

[0058] In addition, as a specific embodiment of the present invention, the filling operation in the fourth step of the present invention can be carried out in stages, and the strength of the filling body in the middle of the filling area 7 is lower than the strength of the filling body at the top and bottom thereof. It should be noted that the filling operation adopts a staged filling method, and because of different sections and different positions of the stope, the strength and proportion of the filling body are also different. The advantage of such a design is that the filling body can be filled according to the specific implementation environment, so that the filling work can achieve the expected use effect without affecting the next stage of mining.

[0059] In addition, in the fifth step of the mining method provided by the present invention, the mining method for each small segment can be mainly from bottom to top along the height direction of the mining field. After each small segment is mined, the small segment is filled, and after the filling operation is completed, the next small segment is mined. In this way, the safety of the mining process is further improved.

[0060] In addition, as a specific implementation of the present invention, the mining method for each mining area in the ore body can be to mine one by one. Interval mining is more conducive to the pressure distribution in the ore body. Mining one by one will not cause the pressure on the rear section of the ore body to increase, while the mining area mined in the front section cannot withstand excessive pressure.

[0061] In order to better understand the pre-controlled top small segment filling method provided by the present invention, the following will be combined with Figures 1 to 10 And a preferred embodiment of the present invention is described.

[0062] In the preferred embodiment, the ore body to be mined is the ore body in the middle section of 3760-4005 of the west area of ​​a gold mine. The average thickness of the ore body is 9.88m, the inclination is 63-80°, and it is mainly steeply inclined medium-thick ore bodies. The mining conditions of the ore bodies in the west area are complex. The upper wall surrounding rock carbonaceous slate is a V-level rock body, the ore body is a IV-level rock body, and the lower wall tuff is a IV-level rock body. The stability of the ore rock is overall unstable, and the overall ore rock joints of the mining area are well developed and relatively broken. The upper wall surrounding rock is a V-level carbonaceous slate. Mining disturbances can easily cause local collapse, which brings challenges and difficulties to safe production. The pre-controlled top small segment filling method provided by the present invention is used for mining, and the specific construction steps are as follows:

[0063] The first step is to arrange and divide the mining area along the direction of the ore body, and then divide it into small sections along the height of the mining area. The mining area is 40m long, 10m wide, 60m high, and about 12-15m high. The mining area is divided into 4-5 small sections for drilling and mining. The top layer height is pre-controlled to be 3-4m, and the height of each small section is 8-9m.

[0064] The second step is to arrange the mining and cutting project, which mainly includes the excavation and digging of the rock drilling access road, the segmented horizontal road 2, the chute 4, the chute connecting road, the vein, the cutting skylight and the cutting cross road. Among them, the net cross-sectional specifications of the rock drilling access road, the segmented horizontal road 2, the vein and the chute connecting road are 3.0~4.0m×3.0m, the cutting skylight is 2.0m×2.0m, the cutting cross road is 2.0m×3.0m, and the chute 4 is 3.0m×3.0m.

[0065] The third step is to set multiple rows of vein anchor cables 9 near the boundary of the upper plate of the ore body to reinforce and support the surrounding rock of the upper plate of each small segment, and the plane where the vein anchor cables 9 in the same row are located is perpendicular to the cross section of the ore body; multiple rows of rock drilling anchor cables 10 are set along the direction of the ore body to reinforce the top plate of each small segment, and the plane where the rock drilling anchor cables 10 in the same row are located is parallel to the cross section of the ore body. Specifically, firstly, the safety net degree of the rock drilling anchor cable 10 installation is designed, and the formula is used for calculation. The length of the stope is 40m, the width of the stope is 10m of the thickness of the ore body, the width of the pre-controlled top rock drilling route is 3~4m, and the height of the rock drilling roadway 3 is 3m. The width of the pre-controlled top rock drilling route is 3~4m, and 4m is taken, then a=2m; the average thickness of the ore body is 10m. Considering that the rock mass of the upper plate is relatively unstable, it is necessary to strengthen the support. The pre-controlled top rock drilling route is the length of the stope, that is, the total length of the pre-controlled top rock drilling route is 40m. Among them, the weight of the ore rock is r = 2.9t / m3, the Proctor coefficient f is 4, the non-uniformity coefficient k is 0.2, and referring to the experience of similar mines, the nominal diameter of the anchor cable is 17.8mm, and the breaking force is 300KN, that is, R = 30t. The safety net calculation formula is: After calculation, the design installation mesh of the anchor cable is:

[0066] When the safety factor m is 1.0:

[0067] When the safety factor m is 1.25:

[0068] When the safety factor m is 1.5:

[0069] Calculation results show that the theoretical installation grid size of the rock drilling anchor 10 in the preferred embodiment is 1.9×1.9m~2.4×2.4m. In order to facilitate on-site construction and ensure the safety of the pre-controlled roof of each small section, 2.0×2.0m is selected as the safety grid size of the rock drilling anchor 10, that is, the row spacing between each row of rock drilling anchors 10 and the spacing between each rock drilling anchor 10 are both 2.0m.

[0070] Then, the design length of the rock drilling anchor cable 10 is determined. The length of the rock drilling anchor cable 10 should be greater than the maximum height of the roof falling. According to the height of the small segment, it can be known that the thickness of the unstable rock layer of the roof is generally 8.0 to 9.0 m. Based on the suspension theory, the length of the long anchor cable can be calculated by the formula: L = L a +L b +L c +L d Calculation is performed, where L is the design length of the rock bolt 10, L a L is the length of the rock bolt 10 that needs to be exposed, preferably 0.5 m; b L is the thickness of anchor, tray and metal mesh, generally 0.15m; c The thickness of the unstable rock layer that needs to be suspended is preferably 8.0-9.0m; L d The anchoring length of the rock drilling anchor 10 deep into the stable rock formation is generally 0.5 to 2.0 m. Substituting it into the formula, the following result can be obtained:

[0071] L=L a +L b +L c +L d =9.15~11.65m

[0072] The calculation results show that the length of the rock drilling anchor 10 is 9.15-11.65 m. Considering the on-site rock exposure conditions, rock drilling equipment, safety factor and other factors, the design length of the rock drilling anchor 10 is determined to be 10.0-12.0 m.

[0073] Because the anchor cable pre-controlled top support technology is adopted, it is mainly used to reinforce the broken surrounding rock of the upper plate and the roof of the mining area, so the number of rows of vein anchor cables 9 set in the vein-penetrating tunnel 8 can be 2 to 3 rows, and then the vein anchor cables 9 need to pass through the flash plate broken ore body to support and reinforce the broken ore body of the upper plate, wherein the spacing of the vein anchor cables 9 in the vein-penetrating tunnel 8 is 1.8m×1.8m, and the length is 12m; at the same time, several rows of rock drilling anchor cables 10 are set along the direction of the ore body in the mining area drilling tunnel 3, and full-length anchor cable support is adopted. The length of the rock drilling anchor cable 10 is 12m, and the safety net of the rock drilling anchor cable 10 is 2.0m×2.0m. The safety net of the rock drilling anchor cable 10 is appropriately adjusted according to the rock condition of the roof exposed by tunnel excavation. When the rock of the mining area roof is unstable, the net width can be appropriately reduced to 1.8m×1.8m.

[0074] Then, after completing the relevant parameter design and specification design, the anchor cable construction is carried out. The YGZ-90 rock drill is used to construct the upward hole with a diameter of 60-65mm. Before construction, the center line is placed on site, the line is drawn on the side wall, and the angle is adjusted according to the design drawings to carry out the construction. If obstacles such as anchor rods are encountered during construction, the anchor cable hole can be adjusted forward and backward appropriately. After the construction of the anchor cable hole is completed, before withdrawing the drill rod, the anchor hole is flushed with high-pressure water to flush away the mineral powder on the hole wall to prevent the hole from being blocked and affecting subsequent installation.

[0075] Then, the steel strand is processed and the rope is fed. The steel strand with a diameter of 17.8mm, a tensile strength of 1860MPa, and a breaking force of 300KN is cut into sections according to the actual hole depth. The length of each section of the steel strand is the actual hole depth + 0.5m. Before feeding the rope, the exhaust pipe 11 is tied with black tape at a distance of 5-10cm from the top of the steel strand, and tied every 2m. During the feeding process of the steel strand, 8# iron wire is tied on the steel strand at a certain interval (2m) to form a cross bracket, and the steel strand is pushed into the bottom of the hole together with the exhaust pipe 11 to fix the steel strand in the center of the drill hole, and then the plugging plug 14 with the grouting pipe 13 and the exhaust pipe 11 inserted is sent to the blocking position. The plugging plug 14 adopts a molded rubber plug.

[0076] Next, grouting construction is carried out, using a ZKHB-3 single-cylinder piston mortar pump for grouting, with a water-cement mass ratio of (0.2-0.3): 1. The grouting pipe 13 uses a 28mm plastic pipe or a plastic pipe of similar size already available in the mine, and the exhaust pipe 11 uses a Φ8mm plastic pipe. The upward hole adopts forward grouting, that is, the grouting pipe 13 is inserted into the plug 14 about 0.2m, and the cement slurry 12 is injected into the hole by the pressure of the grouting pump. The grouting is stopped when water comes out of the exhaust pipe 11. The grouting pressure of the upward hole is 3MPa.

[0077] Finally, the anchor is installed one day after the grouting and curing (after the initial setting period). The support plate uses a 200mm×200mm×20mm steel plate, and the lock is fixed to the support plate and the steel strand with a tensioner, with a tension force of 60-80MPa.

[0078] The fourth step is to carry out mining. First, rock drilling is carried out. A down-the-hole drilling trolley is used to drill vertical medium-deep holes downwards. However, the roof support in the drilling tunnel 3 must be well done to prevent the danger of collapse. Then, the hole network is arranged. In the drilling tunnel 3, starting from the end, a down-the-hole drilling trolley is used to drill vertical medium-deep holes downwards. The diameter of the blasthole 5 is 76mm, the row spacing of the blasthole 5 is 1.8m to 2.0m, and the distance from the bottom of the hole is 1.8 to 2.0m. Each time blasting is done, 2 to 3 rows are arranged, and the blast holes 5 between rows are staggered; then blasting is carried out, using segmented blasting, the depth of the blast holes 5 is about 8 to 9 meters, and the charge is charged in intervals in the hole, the height of each layer of charge is 1.5 meters, and the next layer of charge is charged at intervals of 0.6 meters, and the hole mouth is blocked at a height of 0.6 meters; then the ore is removed from the stope, and the mining starts from the end of the stope, that is, the side of the cutting shaft, using the backward mining method, and the collapsed ore 6 in the segmented stope is firstly carried by a manually driven scraper Part of the ore is shoveled out from the drilling chamber, and the remaining ore is shoveled out from the drilling tunnel 3 into the empty area of ​​the mining area by a remote-controlled shovel loader and transported to the chute 4, where the ore is pulled to the surface by a dump truck; finally, the interior of the mining area is ventilated, and fresh air flows into the drilling chamber of this section from the segmented horizontal tunnel 2 of this section. After flushing the working face in the mining area, the polluted air enters the drilling tunnel 3 of the previous section and is discharged to the segmented horizontal tunnel 2 of the previous section, and then discharged to the surface through the return air tunnel.

[0079] Next, backfilling is carried out. The preparation work before backfilling is mainly to seal the mining area and separate the entire mining area from all the shafts and tunnels outside to prevent the loss and pollution of the filling materials. Secondly, appropriate water filtering facilities are installed on the partition wall to prevent water accumulation in the mining area and reduce the pressure at the bottom of the mining area. The backfill retaining wall is made of brick or steel structure.

[0080] The filling of the mining area is carried out in stages. The strength and proportion of the filling body are different in different sections and locations of the mining area. High-strength filling bodies are used at the bottom and top of the segmented mining area, and the filling body strength can be appropriately reduced in the middle of the mining area. At the beginning of the filling operation, the rising height of the primary material surface should be strictly controlled to ensure the stability of the retaining wall. When starting to fill, the primary filling height is controlled within 1m, and filling can be continued only after the filling body solidifies. After the filling surface exceeds the highest point of the filling retaining wall, the primary filling height is controlled at 2m, but the principle is that there is no water accumulation on the surface of the filling body.

[0081] Finally, when the filling body reaches a certain strength, the adjacent mine room can be mined. In order to reduce the vibration damage of blasting to the filling body, two-step block mining shall not be carried out on both sides of the filling body at the same time.

[0082] The method for pre-controlled top small-segment filling mining provided by the present invention can mine steeply inclined broken medium-thick ore bodies with high safety and high working efficiency.

[0083] In the description of the present invention, the description with reference to the terms "one embodiment", "some embodiments", "a specific implementation", etc. means that the specific features, structures, materials or characteristics described in conjunction with the embodiment or example are included in at least one embodiment or example of the present invention. In the present invention, the schematic representation of the above terms does not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials or characteristics described may be combined in any one or more embodiments or examples in a suitable manner.

[0084] The preferred embodiments of the present invention are described in detail above in conjunction with the accompanying drawings. However, the present invention is not limited to the specific details in the above embodiments. Within the technical concept of the present invention, a variety of simple modifications can be made to the technical solution of the present invention, and these simple modifications all belong to the protection scope of the present invention.

[0085] It should also be noted that the various specific technical features described in the above specific embodiments can be combined in any suitable manner without contradiction. In order to avoid unnecessary repetition, the present invention will not further describe various possible combinations.

[0086] In addition, various embodiments of the present invention may be arbitrarily combined, and as long as they do not violate the concept of the present invention, they should also be regarded as the contents disclosed by the present invention.

Claims

1. A pre-controlled top small segment filling mining method, It is characterized in that The following steps are involved: S1. Arrange and divide the stope along the strike of the ore body, and divide the stope into small sections along the height direction; S2, arranging the mining and cutting works for the stope; S3. Arrange multiple rows of vein-penetrating anchor cables (9) near the boundary of the upper plate of the ore body to reinforce and support the surrounding rock of the upper plate of each of the sub-segments, and the planes of the vein-penetrating anchor cables (9) in the same row are perpendicular to the cross-section of the ore body; arrange multiple rows of rock-drilling anchor cables (10) along the direction of the ore body to reinforce the top plate of the sub-segments, and the planes of the rock-drilling anchor cables (10) in the same row are parallel to the cross-section of the ore body; S4, mining the small segments, and performing filling operations after mining is completed; S5. Repeat steps S3 and S4 in sequence until the mining of the stope is completed.

2. The pre-controlled top small-segment filling mining method according to claim 1, It is characterized in that In step S1, the width of the mining area is 40-50m, the height of the mining area is 50-60m, and one mining area is divided into 4-5 small sections, the height of each small section is 8-9m, and each small section is provided with a 3-4m pre-controlled top.

3. The pre-controlled top small-segment filling mining method according to claim 1, It is characterized in that In step S2, a rock drilling tunnel (3), a segmented horizontal tunnel (2), a chute (4), a chute connecting tunnel, a vein tunnel (8), a cutting skylight, a cutting cross tunnel and a middle transport tunnel (1) are arranged to carry out the mining and cutting project, wherein the net cross-sectional specifications of the rock drilling tunnel (3), the segmented horizontal tunnel (2), the vein tunnel (8) and the chute connecting tunnel are 9 to 12 m2, the specification of the cutting skylight is 4 m2, the specification of the cutting cross tunnel is 6 m2, and the specification of the chute (4) is 9 m2.

4. The pre-controlled top small-segment filling mining method according to claim 3, It is characterized in that A plurality of rows of blast holes (5) are arranged downwardly at the bottom of the rock drilling tunnel (3); the blast holes (5) in the same row are arranged in a fan shape, and the diameter of the blast holes (5) is 76 mm. The row spacing between the blast holes (5) is 1.8 m to 2.0 m, the hole bottom distance of the blast holes (5) is 1.8 to 2.0 m, and the blast holes (5) in each row are arranged in a staggered manner.

5. The pre-controlled top small-segment filling mining method according to claim 1, It is characterized in that In step S3, a plurality of rows of the vein-penetrating anchor cables (9) are arranged from outside the vein to inside the vein.

6. The pre-controlled top small-segment filling mining method according to claim 3, It is characterized in that In step S3, the safety net of the rock bolt (10) is calculated by the formula: Calculation is performed, where D is the safety net, k is the unevenness coefficient, f is the Proctor coefficient, R is the breaking force, a is the width of the rock drilling tunnel, r is the weight of the ore rock, and m is the safety factor.

7. The pre-controlled top small-segment filling mining method according to claim 1, It is characterized in that In step S3, the design length of the rock bolt (10) is calculated by the formula: Calculation is performed, wherein L is the design length of the rock drilling bolt (10), L a The length of the rock bolt (10) to be exposed is L b is the thickness of the anchor, tray and metal mesh, L c is the thickness of the unstable rock layer that needs to be suspended, L d The anchoring length of the rock bolt (10) penetrating into a stable rock formation.

8. The pre-controlled top small-segment filling mining method according to claim 1, It is characterized in that In step S4, the filling operation is carried out in stages, and the strength of the filling body in the middle of the filling area (7) is lower than the strength of the filling body at the top and bottom thereof.

9. The pre-controlled top small-segment filling mining method according to claim 1, It is characterized in that In step S5, the mining method for each small segment is to mine one by one from bottom to top along the mining area height, and after each small segment is mined, the filling operation is performed on it, and after the filling operation is completed, the next small segment is mined.

10. The pre-controlled top small-segment filling mining method according to claim 1, It is characterized in that The mining method for each of the mining areas is to mine every other mining area along the direction of the ore body.

Images