Construction Method of High-Strength Isolation Layer-Side-Rack Cast-in-Place Pile Group-Anchor Cable Net Spatial Bearing Structure in Deep Fractured Ore Bodies

Abstract

This invention provides a method for constructing a spatial load-bearing structure in deep, fractured ore bodies, consisting of a high-strength isolation layer, sidewall pile group, and anchor cable mesh. The method involves first dividing the ore body into an upper and lower section. A high-strength reinforced concrete isolation layer is constructed in the upper ore body using a roadway construction method. After completion, a sidewall pile group is constructed in the lower ore body. This method addresses both the challenging mining conditions of deep, fractured rock, utilizing a roadway mining method in conjunction with anchor cable and steel mesh support to construct the high-strength reinforced concrete isolation layer, and the fractured surrounding rock and sidewall pile group. After the entire high-strength isolation layer, sidewall pile group, and anchor cable mesh spatial load-bearing structure is completed, the anchor cables in both directions interweave to form an anchor cable mesh. Grouting is used to "weave" the unstable rock strata on the sidewalls of the stope into a unified whole. Finally, grouting is used to reinforce the entire anchor cable mesh, maintaining the stability of the sidewalls.

Description

Technical Field

[0001] This invention relates to the field of underground mining technology, and in particular to a method for constructing a spatial bearing structure of high-strength isolation layer-side wall pile group-anchor cable net in deep fractured ore bodies, which is applied to the reconstruction of the mining environment during the mining process of fractured ore. Background Technology

[0002] With the continuous exploitation of mineral resources, domestic and foreign resource development has moved into deeper areas. As the depth of the ore body increases, the characteristics of high ground temperature, high ground stress, high osmotic pressure, and extreme susceptibility to disturbance become apparent, marking the beginning of another stage in mineral resource exploitation. This stage will face many technical challenges, and the difficulty of mining will be greatly increased if the surrounding rock or ore body is fractured.

[0003] In the prior art, patent application number CN201210076204.4, entitled "Method for Inducing Collapse Mining Under an Artificial False Roof," discloses a mining method using an artificial false roof. This method involves directly installing 1-2 layers of steel pipe piles on the steeply inclined stope roof and grouting to reinforce the roof, or directly cementing reinforced concrete to replace the ore body, forming an artificial false roof. Then, the bottom is gradually pulled down along the strike of the stope, while simultaneously using deep-hole pre-splitting blasting to sever the connection between the ore body and the hanging wall and footwall, inducing the ore body to naturally collapse. This prevents the ore body from collapsing through one or more sections of the upper part of the stope during the collapse process, thus protecting the upper aquitard from damage. However, this technical solution does not involve the reinforcement of the stope sidewalls, therefore it does not contribute to increasing the stope length. Furthermore, this artificial false roof scheme cannot achieve long-term stable control of the stope roof and cannot create a stable mining space to prepare for backfilling.

[0004] Patent application CN202210694904.3, entitled "Artificial False Bottom and Manufacturing Method for Thin Vein Stopes," discloses an artificial false bottom for thin vein stopes. The artificial false bottom is installed in the preparatory roadway and includes an internal structure and functional fillers within the internal structure. The artificial false bottom is fixed to the surrounding rock of the roadway via connectors and is integrated with the surrounding rock. The internal structure includes an upper steel mesh, a lower steel mesh, and a composite beam between the upper and lower steel meshes. The functional fillers are composed of foamed concrete and toughened polypropylene synthetic fibers. This artificial false bottom replaces the top and bottom pillars of the stope in thin veins, eliminating the need for pre-reservation during mining and avoiding subsequent recycling. However, this technical solution also fails to address the issue of sidewall stability control in fractured ore bodies. Furthermore, this technical solution is primarily designed for small-span stopes in thin veins and cannot achieve efficient mining of large-span fractured ore bodies.

[0005] Therefore, designing a construction method for a spatial bearing structure of high-strength isolation layer-side pile group-anchor cable net in deep fractured ore bodies is of great significance for ensuring the safe and efficient mining of fractured ore bodies in deep mines. Summary of the Invention

[0006] To address the current problems of difficult, low-safety, and inefficient mining of fractured ore bodies in deep mines, this invention provides a method for constructing a spatial bearing structure of high-strength isolation layer-side wall pile group-anchor cable net in deep fractured ore bodies, so as to improve the mining efficiency of deep fractured ore bodies, reduce mining costs, and achieve safe and efficient mining.

[0007] This invention provides a method for constructing a spatial load-bearing structure in deep fractured ore bodies, comprising the following steps: (High-strength isolation layer - sidewall cast-in-place pile group - anchor cable net)

[0008] S1, before mining the deep fractured ore body, the ore body is divided into an upper ore body and a lower ore body;

[0009] The lower ore body is divided into a first-stage stope and a second-stage pillar. The height of the first-stage stope is the same as the height of the lower ore body, and the width is 6-8m. The height of the second-stage pillar is the same as the height of the lower ore body, and the width is 8-12m. The first-stage stope and the second-stage pillar are alternated and mined in an alternating manner, with the first-stage stope being mined first, followed by the second-stage pillar.

[0010] S2, a high-strength reinforced concrete isolation layer is constructed in the upper ore body using the approach construction method, with the approach direction perpendicular to the mining direction; the high-strength reinforced concrete isolation layer consists of a single-layer approach with a thickness of 2-2.5m;

[0011] The upper ore body is divided into a one-step access method stope and a two-step access method stope, and is mined in two steps. The one-step access method stope and the two-step access method stope are alternated and mined in an alternating manner, with the one-step access method stope being mined first and then the two-step access method stope being mined.

[0012] After the first step of the approach method is completed, the high-strength reinforced concrete isolation layer is constructed. After the construction is completed, the second step of the approach method is carried out.

[0013] S3, After the mining is completed, construct the side wall grouting pile group of the lower ore body;

[0014] S31, corresponding to the boundary between the first-step stope and the second-step pillar in the lower ore body, uses a drilling rig to construct downward left-angled anchor cable holes, right-angled anchor cable holes and grouting holes;

[0015] S32, construct the left inclined anchor cable, right inclined anchor cable and vertical anchor cable of grouting pile respectively, and reinforce with grout;

[0016] S33, lay 15-20cm of crushed stone on the bottom plate of the quarry, and control the size of the crushed stone between 2-5cm;

[0017] S34, then lay the steel mesh, which is arranged at the bottom, top and both sides;

[0018] Both sides of the steel mesh are laid with main and secondary reinforcing bars made of 8-12mm diameter threaded steel bars, spaced 0.2-0.3m apart. The intersections of the main and secondary reinforcing bars are tied firmly with 10-12mm diameter iron wire. Then, connecting threaded steel bars with a length of 0.8-1.0m and a diameter of 18-22mm are inserted into the holes drilled for horizontal and inclined connecting threaded steel bars. The steel meshes on both sides are tied to the connecting threaded steel bars with 10-12mm diameter iron wire to fix the steel meshes on both sides.

[0019] The main reinforcement bars of the bottom reinforcement mesh are made of threaded steel bars with a diameter of 12-18mm and a spacing of 0.4-0.7m. The secondary reinforcement bars are made of threaded steel bars with a diameter of 8-12mm and a spacing of 0.2-0.3m. The main reinforcement bars are at the bottom and the secondary reinforcement bars are at the top. The intersection of the main reinforcement bars and the secondary reinforcement bars is tied firmly with iron wire with a diameter of 10-12mm. The intersection of the bottom reinforcement mesh and the threaded steel bars connecting the two sides is also tied firmly with iron wire with a diameter of 10-12mm.

[0020] The main and secondary reinforcement bars of the top reinforcement mesh are laid in the same manner as the bottom reinforcement mesh;

[0021] After the reinforcement is laid (S35), a retaining wall with a thickness of 0.3m-0.6m is built at the entrance using hollow slag bricks or cement hollow bricks; a high-strength isolation layer artificial roof with concrete side anchor cables is used, and the concrete meets the C25 strength requirements. The width of the high-strength isolation layer artificial roof is 3-4m, the thickness is 2-2.5m, and the length needs to extend 2-3m beyond the boundaries of the two mining areas.

[0022] As a further improvement of the present invention, the side-mounted cast-in-place pile group includes 10-15 sets of left inclined anchor cable holes, right inclined anchor cable holes and grouting holes, forming an interlaced anchor cable net.

[0023] As a further improvement of the present invention, the diameter of the left inclined anchor cable hole is 60-70mm, and the angle with the ground is 100°-110°; the diameter of the right inclined anchor cable hole is 60-70mm, and the angle with the ground is 70°-80°; the diameter of the grouting hole is 150-250mm, and it is drilled perpendicular to the ground.

[0024] As a further improvement of the present invention, the left oblique anchor cable hole, the right oblique anchor cable hole, and the grouting hole are staggered by 0.3-0.5m in all directions, and the anchor cables in the same direction are on the same plane.

[0025] As a further improvement of the present invention, in step S32, the construction process of the grouting pile is as follows: a disc locator is placed and fixed on the drilled grouting hole, and then the prepared anchor cable is inserted into the anchor cable hole corresponding to the disc locator. The anchor cable lowering speed is controlled until the anchor cable reaches the bottom of the hole. This step is repeated until all the anchor cables are placed. Then, grout is injected into the grouting hole until the grout overflows, thus completing the construction of the grouting pile.

[0026] As a further improvement of the present invention, the disc positioner includes a grouting hole disposed in the middle and a plurality of anchor cable holes arranged around the outer periphery of the grouting hole; the disc positioner is provided with 4-8 anchor cable holes.

[0027] As a further improvement of the present invention, the size of the disc positioner is consistent with the size of the grouting hole.

[0028] As a further improvement of the present invention, the access routes of the first-step stope and the second-step stope of the upper ore body are spatially intersected with those of the first-step stope and the second-step pillar of the lower ore body.

[0029] As a further improvement of the present invention, the span of the first-step mining area and the second-step mining area of ​​the approach method are both 3 to 4 meters.

[0030] As a further improvement of the present invention, in step S2, constructing a high-strength reinforced concrete isolation layer includes the following steps: constructing vertically upward anchor cables on the top slab of the access road, wherein the length of the anchor cables is 10-12m, the row spacing is 1.5-1.8m, the hole spacing is 1.5-1.8m, and the exposed section of the anchor cables is reserved for 2.5-3.0m; drilling the horizontal connecting threaded steel holes every 0.8-1.2m at a distance of 0.4-0.5m from the bottom slab on both sides of the access road, with a drilling depth of 0.5-1.0m; drilling the inclined connecting threaded steel holes every 0.8-1.2m at a distance of 2.0-2.5m from the bottom slab on both sides of the access road, with a drilling depth of 0.5-1.0m and a drilling inclination angle of 0-45°.

[0031] The beneficial effects of the present invention are:

[0032] 1. The present invention provides a method for constructing a spatial bearing structure for a high-strength isolation layer, sidewall cast-in-place pile group, and anchor cable net in deep fractured ore bodies. On one hand, it addresses the mining conditions of deep, fractured ore bodies by using the approach mining method, in conjunction with anchor cable and steel mesh support, to construct a high-strength reinforced concrete isolation layer. On the other hand, it addresses the sidewall cast-in-place pile group in fractured surrounding rock and ore bodies. After the entire high-strength isolation layer, sidewall cast-in-place pile group, and anchor cable net spatial bearing structure is completed, the anchor cables in both directions interweave to form an anchor cable net. Grouting is used to "weave" the unstable rock strata on the sidewall of the stope into a whole. Finally, grouting is used to reinforce the entire anchor cable net through grouting holes, thus maintaining the stability of the sidewall.

[0033] By employing a synergistic control system of cast-in-place piles and anchor cables, the physical and mechanical properties of the sidewall ore were improved, enhancing its resistance to damage. Therefore, even with increased stope length and height, and a larger exposed sidewall area, the stability of the stope sidewalls can still be guaranteed. In other words, this sidewall control technology ensures sidewall stability, providing a stable mining environment; it also increases the exposed sidewall area, allowing for larger stope lengths and heights, thereby increasing stope structural parameters and improving stope production capacity. This provides an engineering application scenario for the safe and efficient mining of fractured ore bodies.

[0034] 2. The construction steps in this invention are relatively simple, which can significantly reduce the construction period. Compared with the artificial false roof structure constructed by the double-layer approach method, it can save more than half the time, thereby achieving an overall cost reduction. In addition, combined with the spatial bearing structure of the side-side cast-in-place pile group, it can realize efficient mining of medium-deep holes with large spans (10-12m), long distances (ore body thickness 35-40m), and large heights (35-40m). Attached Figure Description

[0035] Figure 1 A schematic diagram of the high-strength isolation layer-side grouting pile group-anchor cable net spatial bearing structure provided by the present invention;

[0036] Figure 2 For along Figure 1 Schematic diagram of the high-strength reinforced concrete isolation layer of the upper ore body of the Middle AA line;

[0037] Figure 3 For along Figure 2 Side view of the high-strength reinforced concrete isolation layer along the BB line;

[0038] Figure 4 For along Figure 3 Top view of the bottom reinforcement mesh of the CC line;

[0039] Figure 5 A schematic diagram of one embodiment of the disc positioner;

[0040] Figure 6 This is a schematic diagram of another implementation of the disc positioner. Detailed Implementation

[0041] To make the objectives, technical solutions, and advantages of this invention clearer, the invention will be described in detail below with reference to the accompanying drawings and specific embodiments.

[0042] It should also be noted that, in order to avoid obscuring the present invention with unnecessary details, only the structures and / or processing steps closely related to the present invention are shown in the accompanying drawings, while other details that are not closely related to the present invention are omitted.

[0043] Additionally, it should be noted that the terms “comprising,” “including,” or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such process, method, article, or apparatus.

[0044] Please see Figures 1 to 6 As shown, this invention provides a method for constructing a spatial bearing structure of a high-strength isolation layer, sidewall cast-in-place pile group, and anchor cable mesh in deep fractured ore bodies. This method, designed for deep, fractured ore mining conditions, utilizes a route mining method, combined with anchor cable and steel mesh support, to construct a high-strength reinforced concrete isolation layer. Furthermore, it addresses the sidewall cast-in-place pile group in fractured surrounding rock and ore bodies. Specifically, it includes the following steps:

[0045] S1, Before mining the deep fractured ore body, the ore body is divided into upper ore body 1 and lower ore body 2;

[0046] The lower ore body 2 is divided into a first-step stope 22 and a second-step pillar 23.

[0047] The first-stage stope 22 has the same height as the lower ore body 2 and a width of 6-8m; the second-stage pillar 23 has the same height as the lower ore body 2 and a width of 8-12m. The first-stage stope 22 and the second-stage pillar 23 are alternated and mined in a one-off manner, with the first-stage stope 22 being mined first, followed by the second-stage pillar 23.

[0048] S2, a high-strength reinforced concrete isolation layer 11 is constructed in the upper ore body 1 using the approach construction method. The approach direction is perpendicular to the mining direction, and the approach dimensions are 3-4m wide × 3-4m high.

[0049] The high-strength reinforced concrete isolation layer 11 consists of a single-layer access road with a thickness of 3-4m;

[0050] In a single-layer access route, the upper ore body 1 is divided into a one-step access stop 12 and a two-step access stop 13, which are mined in two steps. The span of both the one-step access stop 12 and the two-step access stop 13 is 3-4m.

[0051] The first-step stope 12 and the second-step stope 13 of the approach method are alternated and mined in an alternating manner, with the first-step stope 12 being mined first and the second-step stope 13 being mined later.

[0052] After the first step of the approach method, stope 12 is completed, a high-strength reinforced concrete isolation layer 11 is constructed. After the isolation layer is completed, the second step of the approach method, stope 13, is then carried out.

[0053] The access routes of the first-step stope 12 and the second-step stope 13 of the upper ore body 1 are spatially intersected with the access routes of the first-step stope 22 and the second-step pillar 23 of the lower ore body 2.

[0054] Specifically, in step S2, constructing a high-strength reinforced concrete isolation layer includes the following steps: Installing vertically upward anchor cables 3 on the top slab of the access road. The length of the anchor cables 3 is 10-12m, the row spacing is 1.5-1.8m, the hole spacing is 1.5-1.8m, and the exposed section of the anchor cables 3 is reserved for 2.5-3.0m; At a distance of 0.4-0.5m from the bottom slab on both sides of the access road, horizontal connecting threaded steel drill holes are installed every 0.8-1.2m, with a drilling depth of 0.5-1.0m; At a distance of 2.0-2.5m from the bottom slab on both sides of the access road, inclined connecting threaded steel drill holes are installed every 0.8-1.2m, with a drilling depth of 0.5-1.0m and an inclination angle of 0-45°, whichever is convenient for installation.

[0055] S3, after the mining is completed, construct the side wall pile group 21 of the lower ore body 2;

[0056] S31: A loader is used to clear away the remaining ore, fallen waste rock, and all other debris from the stope floor. Corresponding to the boundary between the first-step stope 22 and the second-step pillar 23 in the lower ore body 2, a YGZ-90 shallow-hole drilling rig is used to construct downward-facing left-angled anchor cable holes 211, right-angled anchor cable holes 212, and grouting holes 213. The sidewall cast-in-place pile group 21 contains multiple sets of left-angled anchor cable holes 211, right-angled anchor cable holes 212, and grouting holes 213, forming an interwoven anchor cable network. Generally, there are 10-15 sets.

[0057] In this embodiment, the diameter of the left oblique anchor hole 211 is 60 mm, and the angle with the ground is 105°; the diameter of the right oblique anchor hole 212 is 60 mm, and the angle with the ground is 75°; the diameter of the grouting hole 213 is 150-250 mm, and it is drilled perpendicular to the ground. It should be understood that, depending on actual needs, the diameter of the left oblique anchor hole can be 60-70 mm, and the angle with the ground can be 100°-110°; the diameter of the right oblique anchor hole can be 60-70 mm, and the angle with the ground can be 70°-80°.

[0058] Preferably, to avoid damage caused by the holes intersecting with each other, the left oblique anchor cable hole 211, the right oblique anchor cable hole 212, and the grouting hole 213 are staggered by 0.3-0.5m in all directions. Furthermore, this ensures that the anchor cables in the same direction are on the same plane, guaranteeing the reinforcement effect of the sidewall.

[0059] The disc locator 5 is placed at the grouting hole 213 for positioning during the construction of the grouting pile anchor cable. The size of the disc locator 5 is the same as that of the grouting hole 213.

[0060] The disc locator 5 includes a grouting hole 52 located in the center and a number of anchor holes 51 arranged around the outer periphery of the grouting hole 52. Preferably, the disc locator 5 can be provided with 4-8 anchor holes 51 depending on the size of the grouting hole 213, so as to be suitable for ore bodies and surrounding rocks with different degrees of fracture.

[0061] S32, construct the left inclined anchor cable, right inclined anchor cable and vertical anchor cable of grouting pile respectively, and reinforce with grout;

[0062] Specifically, in step S32, the construction process of the grouting pile is as follows: Place and fix the disc locator 5 on the drilled grouting hole 213, then insert the prepared anchor cable into the corresponding anchor cable hole 51 of the disc locator 5, control the anchor cable lowering speed until the anchor cable reaches the bottom of the hole, repeat this step until all anchor cables are placed; then inject grout into the grouting hole 52 until the grout overflows, thus completing the construction of the grouting pile.

[0063] S33, lay 15-20cm of crushed stone 6 on the bottom plate of the quarry. The size of the crushed stone 6 should be controlled at about 5cm, generally 2-5cm.

[0064] S34, then lay the steel mesh, which is arranged at the bottom, top and both sides;

[0065] Both sides of the steel mesh are laid with main and secondary reinforcing bars made of 8-12mm diameter threaded steel bars, spaced 0.2-0.3m apart. The intersections of the main and secondary reinforcing bars are tied firmly with 10-12mm diameter iron wire. Then, connecting threaded steel bars with a length of 0.8-1.0m and a diameter of 18-22mm are inserted into the holes drilled for horizontal and inclined connecting threaded steel bars. The steel meshes on both sides are tied to the connecting threaded steel bars with 10-12mm diameter iron wire to fix the steel meshes on both sides.

[0066] The main reinforcement 71 (horizontal reinforcement) of the bottom reinforcement mesh is made of threaded steel with a diameter of 12-18mm and a spacing of 0.4-0.7m. The secondary reinforcement 72 (longitudinal reinforcement) is made of threaded steel with a diameter of 8-12mm and a spacing of 0.2-0.3m. The main reinforcement 71 is at the bottom and the secondary reinforcement 72 is at the top. The intersection of the main reinforcement 71 and the secondary reinforcement 72 is tied firmly with iron wire with a diameter of 10-12mm. The intersection of the bottom reinforcement mesh and the threaded steel connecting the two sides is also tied firmly with iron wire with a diameter of 10-12mm.

[0067] The laying of the main reinforcement 71 (transverse reinforcement) and secondary reinforcement 72 (longitudinal reinforcement) of the top reinforcement mesh is consistent with the laying of the bottom reinforcement mesh;

[0068] After the reinforcement is laid (S35), a retaining wall with a thickness of 0.3-0.6m is built at the entrance using hollow slag bricks or cement hollow bricks; a high-strength isolation layer artificial false roof with concrete side anchor cables is used, and the concrete meets the C25 strength requirements. The width of the high-strength isolation layer artificial false roof is 3-4m, the thickness is 2-2.5m, and the length needs to extend 2-3m beyond the boundaries of the two mining areas at both ends.

[0069] That is, after the first-step mining of the access method 12 is completed, a high-strength reinforced concrete isolation layer 11 is constructed. After the construction is completed, the second-step mining of the access method is carried out. After the mining is completed, the side wall grouting pile group 21 of the lower ore body 2 is constructed according to steps S31-S35, thus completing the construction of the entire high-strength isolation layer-side wall grouting pile group-anchor cable net spatial bearing structure.

[0070] With this setup, after the entire high-strength isolation layer-side wall pile group-anchor cable net spatial bearing structure is completed, the anchor cables in both directions intersect to form an anchor cable net. Grouting is used to "weave" the unstable rock strata on the side of the mining area into a whole. Finally, grouting is used to reinforce the entire anchor cable net through grouting holes to maintain the stability of the side wall.

[0071] In summary, this invention provides a method for constructing a spatial bearing structure for deep, fractured ore bodies, consisting of a high-strength isolation layer, sidewall cast-in-place pile group, and anchor cable mesh. On one hand, it addresses the mining conditions of deep, fractured ore bodies by employing a route mining method, in conjunction with anchor cable and steel mesh support, to construct a high-strength reinforced concrete isolation layer. On the other hand, it addresses the sidewall cast-in-place pile group within the fractured surrounding rock and ore body. Through the coordinated control of the cast-in-place pile group and anchor cable mesh, the stability of the sidewalls is ensured, the exposed area of ​​the sidewalls is increased, and the length and height of the stope can be expanded, thereby increasing the structural parameters of the stope and improving its production capacity. This provides an engineering application scenario for the safe and efficient mining of fractured ore bodies.

[0072] The above embodiments are only used to illustrate the technical solutions of the present invention and are not intended to limit it. Although the present invention has been described in detail with reference to preferred embodiments, those skilled in the art should understand that modifications or equivalent substitutions can be made to the technical solutions of the present invention without departing from the spirit and scope of the technical solutions of the present invention.

Claims

1. A method for constructing a spatial load-bearing structure of high-strength isolation layer-side wall pile group-anchor cable net in deep fractured ore bodies, characterized in that, Includes the following steps: S1, before mining the deep fractured ore body, the ore body is divided into an upper ore body and a lower ore body; The lower ore body is divided into a first-stage stope and a second-stage pillar. The height of the first-stage stope is the same as the height of the lower ore body, and the width is 6-8m. The height of the second-stage pillar is the same as the height of the lower ore body, and the width is 8-12m. The first-stage stope and the second-stage pillar are alternated and mined in an alternating manner, with the first-stage stope being mined first, followed by the second-stage pillar. S2, a high-strength reinforced concrete isolation layer is constructed in the upper ore body using the approach construction method, with the approach direction perpendicular to the mining direction; the high-strength reinforced concrete isolation layer consists of a single-layer approach with a thickness of 2-2.5m; The upper ore body is divided into a one-step access method stope and a two-step access method stope, and is mined in two steps. The one-step access method stope and the two-step access method stope are alternated and mined in an alternating manner, with the one-step access method stope being mined first and then the two-step access method stope being mined. After the first step of the approach method is completed, the high-strength reinforced concrete isolation layer is constructed. After the construction is completed, the second step of the approach method is carried out. S3, After the mining is completed, construct the side wall grouting pile group of the lower ore body; S31, corresponding to the boundary between the first-step stope and the second-step pillar in the lower ore body, uses a drilling rig to construct downward left-angled anchor cable holes, right-angled anchor cable holes and grouting holes; S32, construct the left inclined anchor cable, right inclined anchor cable and vertical anchor cable of grouting pile respectively, and reinforce with grout; S33, lay 15-20cm of crushed stone on the bottom plate of the quarry, and control the size of the crushed stone between 2-5cm; S34, then lay the steel mesh, which is arranged at the bottom, top and both sides; Both sides of the steel mesh are laid with main and secondary reinforcing bars made of 8-12mm diameter threaded steel bars, spaced 0.2-0.3m apart. The intersections of the main and secondary reinforcing bars are tied firmly with wire. Then, connecting threaded steel bars with a length of 0.8-1.0m and a diameter of 18-22mm are inserted into the holes drilled for horizontal and inclined connecting threaded steel bars. The steel meshes on both sides are tied to the connecting threaded steel bars with wire to fix the steel meshes on both sides. The main reinforcement bars of the bottom reinforcement mesh are made of threaded steel bars with a diameter of 12-18mm and a spacing of 0.4-0.7m. The secondary reinforcement bars are made of threaded steel bars with a diameter of 8-12mm and a spacing of 0.2-0.3m. The main reinforcement bars are at the bottom and the secondary reinforcement bars are at the top. The intersection of the main reinforcement bars and the secondary reinforcement bars is tied firmly with wire. The intersection of the bottom reinforcement mesh and the threaded steel bars connecting the two sides is also tied firmly with wire. The main and secondary reinforcement bars of the top reinforcement mesh are laid in the same manner as the bottom reinforcement mesh; S35, after the reinforcement is laid, a retaining wall is built at the entrance using hollow slag bricks or cement hollow bricks; a high-strength isolation layer artificial false roof with concrete side anchor cables is used, the concrete meets the C25 strength requirement, the width of the high-strength isolation layer artificial false roof is 3-4m, the thickness is 2-2.5m, and the length direction needs to extend 2-3m beyond the boundaries of the two mining areas.

2. The construction method of the spatial bearing structure of high-strength isolation layer-side wall pile group-anchor cable net in deep fractured ore body according to claim 1, characterized in that: The side-mounted cast-in-place pile group includes 10-15 sets of left-angled anchor cable holes, right-angled anchor cable holes and grouting holes, forming an interlaced anchor cable network.

3. The construction method of the spatial bearing structure of high-strength isolation layer-side wall pile group-anchor cable net in deep fractured ore body according to claim 1, characterized in that: The diameter of the left inclined anchor cable hole is 60-70mm, and the angle with the ground is 100°-110°; the diameter of the right inclined anchor cable hole is 60-70mm, and the angle with the ground is 70°-80°; the diameter of the grouting hole is 150-250mm, and it is drilled perpendicular to the ground.

4. The construction method of the spatial bearing structure of high-strength isolation layer-side wall pile group-anchor cable net in deep fractured ore body according to claim 3, characterized in that, The left inclined anchor cable hole, the right inclined anchor cable hole, and the grouting hole are staggered by 0.3-0.5m in all directions.

5. The construction method of the spatial bearing structure of high-strength isolation layer-side wall pile group-anchor cable net in deep fractured ore body according to claim 1, characterized in that, In step S32, the construction process of the grouting pile is as follows: a disc locator is placed and fixed on the drilled grouting hole. The disc locator includes a grouting hole in the middle and several anchor cable holes around the grouting hole. Then, the prepared anchor cable is inserted into the corresponding anchor cable hole of the disc locator, and the lowering speed of the anchor cable is controlled until the anchor cable reaches the bottom of the hole. This step is repeated until all the anchor cables are placed. Then, grout is injected into the grouting hole until the grout overflows, thus completing the construction of the grouting pile.

6. The construction method of the spatial bearing structure of high-strength isolation layer-side wall pile group-anchor cable net in deep fractured ore body according to claim 5, characterized in that: The disc positioner is provided with 4-8 anchor cable holes.

7. The construction method of the spatial bearing structure of high-strength isolation layer-side wall pile group-anchor cable net in deep fractured ore body according to claim 5, characterized in that: The size of the disc positioner is the same as the size of the grouting hole.

8. The construction method of the spatial bearing structure of high-strength isolation layer-side wall pile group-anchor cable net in deep fractured ore body according to claim 1, characterized in that, The access routes of the first-step and second-step access methods of the upper ore body are spatially intersected with the access routes of the first-step stope and second-step pillar of the lower ore body.

9. The construction method of the spatial bearing structure of high-strength isolation layer-side wall pile group-anchor cable net in deep fractured ore body according to claim 1, characterized in that: The span of both the first-step and second-step mining areas of the approach method is 3-4m.

10. The construction method of the spatial bearing structure of high-strength isolation layer-side wall pile group-anchor cable net in deep fractured ore body according to claim 1, characterized in that, In step S2, constructing a high-strength reinforced concrete isolation layer includes the following steps: Installing vertically upward anchor cables on the top slab of the access road, the anchor cables being 10-12m long, spaced 1.5-1.8m apart, and having a hole spacing of 1.5-1.8m, with an exposed section of 2.5-3.0m reserved; drilling horizontal connecting threaded steel holes every 0.8-1.2m at a distance of 0.4-0.5m from the bottom slab on both sides of the access road, with a drilling depth of 0.5-1.0m; drilling inclined connecting threaded steel holes every 0.8-1.2m at a distance of 2.0-2.5m from the bottom slab on both sides of the access road, with a drilling depth of 0.5-1.0m and an inclination angle of 0-45°.

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