Distributed rigid-flexible coupling bottom structure construction method

Abstract

The invention discloses a distributed rigid-flexible coupling bottom structure construction method, and belongs to the technical field of mine engineering, a rock mass stress transfer path is actively cut off through a presplitting space, a continuous bottom structure is divided into independent units, and therefore the problems of maximum principal stress concentration and blasting vibration accumulation conduction are solved; on the other hand, step-by-step stoping is matched with peach-shaped ore pillar forming, a rigid ore pillar bearing structure is formed by combining a filling body formed through double retaining wall guarantee, and a rigid-flexible coupling system is formed by combining flexible interval unloading of a presplitting space, so that structural deformation caused by sedimentation of the filling body is resisted, and linkage diffusion of local damage is avoided; the problems that in a traditional method, a super-large-scale panel bottom structure is prone to being disturbed, and production is prone to being interrupted are solved in a targeted mode.

Description

TECHNICAL FIELD

[0001] The application belongs to the technical field of mine engineering, and particularly relates to a distributed rigid-flexible coupling bottom structure construction method. BACKGROUND

[0002] In recent years, with the increasing development of deep mineral resources, the number of mines for mining super-large thick ore bodies continues to increase, and the mine infrastructure and production scale are expanding simultaneously. Combined with the occurrence conditions of ore bodies, the size of the mining panel of such mines often breaks through 200m x 200m, forming a super-large scale mining unit.

[0003] In such panel mining, the roadway engineering of the bottom structure needs to be constructed in advance before the stoping operation, and continuously bears double core loads throughout the entire mining cycle. It is easy to be disturbed during production, leading to unstable structure and affecting production efficiency. SUMMARY

[0004] In view of the technical problems in the background art, the application provides a distributed rigid-flexible coupling bottom structure construction method, which comprises: arranging the preparation engineering in the bottom structure of the super-large scale panel; in the bottom structure of the super-large scale panel, the pre-splitting blast holes are arranged along the strike of the ore body to be mined at intervals; performing pre-splitting blasting to form a pre-splitting space, which is within the peach-shaped ore pillar, and the two peach-shaped ore pillars containing the pre-splitting space are not adjacent; stopping the step stope, and forming the inclined surface of one side of the peach-shaped ore pillar by constructing inclined holes and blasting in the ore body; constructing an arched filling retaining wall at the pre-splitting space formed in the peach-shaped ore pillar draw-off roadway, and at the same time, setting an additional retaining wall at the intersection section of the step stope and the two-step stope draw-off roadway, and then filling the step stope goaf; after the filling body of the step stope reaches the designed strength and is fully consolidated, carrying out the two-step stope stoping operation, and forming the inclined surface of the other side of the peach-shaped ore pillar by constructing inclined holes and blasting, thereby forming the peach-shaped ore pillar.

[0005] In some embodiments, the preparation engineering comprises, on the basis of the development engineering of the upper panel along the vein transportation roadway, the lower panel along the vein transportation roadway and the panel through-vein roadway, sequentially constructing the draw-off roadway, the draw-off roadway and the draw-off access to constitute a complete panel bottom structure engineering system.

[0006] In some embodiments, the section size of the draw-off roadway, the draw-off roadway and the draw-off access needs to meet the requirements of ore drawing and ventilation, and provide operation space for subsequent pre-splitting blasting operation.

[0007] In some embodiments, the pre-splitting blast hole is arranged along the direction of the ore extraction roadway of the bottom structure, and a buffer layer is reserved between the bottom of the pre-splitting blast hole and the boundary of the bottom structure; the buffer layer is used to avoid damage to the main body of the bottom structure caused by pre-splitting blasting, so as to accurately control the blasting influence range.

[0008] In some embodiments, the pre-splitting blasting adopts an interlaced uncoupled charging structure.

[0009] In some embodiments, during the one-step stope recovery, upward fan-shaped medium-length holes are drilled in the upper part of the segment drilling roadway and the bottom ore receiving roadway, and inclined short blast holes are drilled adjacent to the stope boundary in the ore receiving roadway; the inclined short blast holes are used to form a ore falling groove to improve the ore flowability and ore extraction efficiency.

[0010] In some embodiments, the blasting of the one-step stope recovery adopts a row-by-row millisecond initiation method of medium-length holes.

[0011] In some embodiments, a preset number of blast holes are initiated each time, the blast holes in the row are divided into at least two sections according to the millisecond delay and are sequentially initiated, and the delay blasting is used between rows.

[0012] In some embodiments, while the arch-shaped filling retaining wall is constructed, an additional retaining wall is arranged at the intersection section of the one-step stope and the two-step stope in the ore receiving roadway.

[0013] In some embodiments, during the two-step stope recovery, the arrangement logic of the upward fan-shaped medium-length holes and the inclined short blast holes used to form the ore falling groove is consistent with that of the one-step stope; and when the inclined hole is drilled to form the other inclined surface of the peach-shaped ore pillar, the drilling direction of the inclined hole is adapted to the inclined hole that forms one inclined surface of the peach-shaped ore pillar in the one-step stope.

[0014] The application provides a distributed rigid-flexible coupling bottom structure construction method, which comprises the following steps: Arranging the preparation engineering in the super-large scale panel bottom structure; In the super-large scale panel bottom structure, pre-splitting blast holes are arranged along the strike of the ore body to be mined; Performing pre-splitting blasting to form a pre-splitting space; Recovering the one-step stope and forming the inclined surface of one side of the peach-shaped ore pillar by drilling and blasting the inclined hole in the ore body; Constructing an arch-shaped filling retaining wall at the pre-splitting space formed in the peach-shaped ore pillar ore extraction roadway, and arranging an additional retaining wall at the intersection section of the one-step stope and the two-step stope in the ore receiving roadway, and then filling the goaf of the one-step stope; After the one-step stope filling body reaches the designed strength and is fully consolidated, the two-step stope recovery operation is carried out, and the inclined surface of the other side of the peach-shaped ore pillar is also formed by drilling and blasting the inclined hole, thereby forming the peach-shaped ore pillar.

[0015] By actively cutting off the stress transmission path of the rock mass through pre-splitting space, the continuous bottom structure is divided into independent units, thereby solving the problems of maximum principal stress concentration and blast vibration accumulation and conduction; on the other hand, step-by-step stoping is combined with the formation of peach-shaped pillars, and the formed filling body is combined with the double retaining wall to form a rigid pillar bearing structure, and the pre-splitting space is combined with the flexible interval unloading to form a rigid-flexible coupling system, which not only resists the structural deformation caused by the settlement of the filling body, but also avoids the local damage chain diffusion, and solves the core problem that the bottom structure is easily disturbed and production is easily interrupted in the traditional method. BRIEF DESCRIPTION OF DRAWINGS

[0016] Figure 1 is a whole layout schematic diagram of a large-scale panel bottom structure and a preparation engineering of a distributed rigid-flexible coupling bottom structure construction method provided in the embodiments of the present application; Figure 2 is a pre-splitting blast hole arrangement and a bottom structure schematic diagram after the formation of a pre-splitting space of a distributed rigid-flexible coupling bottom structure construction method provided in the embodiments of the present application; Figure 3 is a top view angle schematic diagram of filling work in a pre-splitting space of a distributed rigid-flexible coupling bottom structure construction method provided in the embodiments of the present application; Figure 4 is a one-step stope in-situ recovery blasting work schematic diagram of a distributed rigid-flexible coupling bottom structure construction method provided in the embodiments of the present application; Figure 5 is a one-step stope and peach-shaped pillar pre-splitting space in-situ filling work schematic diagram of a distributed rigid-flexible coupling bottom structure construction method provided in the embodiments of the present application.

[0017] The reference signs are explained as follows: 1, panel chute; 2, upper panel along-vein transportation roadway; 3, ore drawing access; 4, ore drawing roadway; 5, filling retaining wall; 6, air return raise; 7, peach-shaped pillar; 8, pre-splitting space; 9, pre-splitting blast hole; 10, arched filling retaining wall; 11, panel inter-column; 12, out-of-vein connecting roadway; 13, to-be-mined stope; 14, to-be-drawn ore; 15, filling body; 16, lower panel along-vein transportation roadway; 17, panel through-vein connecting roadway; 18, one-step stope ore receiving roadway; 19, one-step stope ore drawing access; 20, two-step stope ore receiving roadway; 21, two-step stope ore drawing access; 22, bottom structure; 23, upward fan-shaped blast hole; 24, segmented drilling roadway; 25, two-step to-be-mined stope; 26, inclined hole for forming peach-shaped pillar; 27, ore falling chute; 28, one-step stope filling body; 30, pre-splitting space filling body; 31, two-step ore receiving roadway filling retaining wall; 32, bottom filling body. DETAILED DESCRIPTION

[0018] The embodiments of the present application will be described in detail below with reference to the drawings. The following examples are only used to more clearly illustrate the technical solutions of the present application, and therefore only serve as examples, and cannot be used to limit the protection scope of the present application.

[0019] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this application belongs; the terminology used herein is for the purpose of describing particular embodiments only and is not intended to be limiting of the present application; the terms "comprising," "comprises" and "including" as used herein are synonymous with and meant to have the same meaning as the term "including"; the term "coupled" as used herein means the joining of two members together with one or more intervening members.

[0020] In the description of the embodiments of the present application, the technical terms "first", "second", etc. are only used to distinguish different objects, and cannot be understood as indicating or implying relative importance or implicitly indicating the number, specific order or primary and secondary relationship of the indicated technical features. In the description of the embodiments of the present application, the meaning of "a plurality of" is two or more, unless otherwise explicitly and specifically limited.

[0021] Reference herein to "an embodiment" means that a particular feature, structure, or characteristic described in connection with the embodiment can be included in at least one embodiment of the application. The appearance of the phrase in various places in the specification does not necessarily all refer to the same embodiment, nor is it necessarily independent or alternative embodiments to each other. It is explicitly and implicitly understood by those skilled in the art that the embodiments described herein can be combined with other embodiments.

[0022] In the description of the embodiments of the present application, the term "and / or" is only a description of the association relationship of the associated objects, which means that there can be three relationships, for example, A and / or B, which can represent the three cases of A alone, A and B together, and B alone. In addition, the character " / " in this paper generally represents that the front and rear associated objects are a "or" relationship.

[0023] In the description of the embodiments of the present application, the term "a plurality of" refers to two or more (including two), and similarly, "a plurality of groups" refers to two or more groups (including two groups), and "a plurality of pieces" refers to two or more pieces (including two pieces).

[0024] In the description of the embodiments of the present application, the orientations or positional relationships indicated by the technical terms "center", "longitudinal", "transverse", "length", "width", "thickness", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", "clockwise", "counterclockwise", "axial", "radial", "circumferential" and the like are based on the orientations or positional relationships shown in the drawings, and are only for the convenience of describing the embodiments of the present application and simplifying the description, and do not indicate or imply that the devices or elements referred to must have a particular orientation, be constructed and operated in a particular orientation, and therefore cannot be understood as limiting the embodiments of the present application.

[0025] In the description of the embodiments of the present application, unless otherwise explicitly specified and limited, the technical terms "mounting", "connection", "connection", "fixing" and the like should be understood broadly, for example, can be fixed connection, can also be detachable connection, or integral; can be mechanical connection, can also be electrical connection; can be directly connected, can also be indirectly connected through an intermediate medium, can be the internal communication of two elements or the interaction relationship between two elements. For those skilled in the art, the specific meanings of the above terms in the embodiments of the present application can be understood according to the specific circumstances.

[0026] In order to make the purpose, technical scheme and advantages of the present application more clear, the present application will be further described in detail below with examples. It should be understood that the specific embodiments described herein are only used to explain the present application and not to limit the present application.

[0027] In recent years, with the increasing development of deep mineral resources, the number of super-large thick ore body mining mines continues to increase, and the mine infrastructure and production scale are expanding synchronously. Combined with the occurrence conditions of ore bodies, the size of the mining panel of such mines often breaks through 200m x 200m, forming a super-large mining unit.

[0028] In such panel mining, the roadway engineering of the bottom structure needs to be constructed in advance before the stoping operation, and continuously bears double core loads throughout the entire mining cycle. On the one hand, the cyclic blasting vibration during the stoping process will propagate through the interconnected roadway network, causing the vibration energy to continuously accumulate inside the structure, especially forming superimposed disturbance to the bottom structure of the terminal stoping section, aggravating the damage risk. On the other hand, due to the limitation of the existing filling process, the lower filling body is difficult to completely interface with the top and has a natural settlement rate, which is easy to cause the settlement of the top filling body, and then drive the settlement deformation of the bottom structure, affecting the structural integrity.

[0029] Meanwhile, in order to maintain the stability of the long side of the stope, the long side direction of the stope is usually kept consistent with the direction of the maximum principal stress, but this arrangement causes the bottom structure to extend vertically to the direction of the maximum principal stress, resulting in obvious stress concentration of the maximum principal stress on the bottom structure, further increasing the probability of structural damage. More importantly, the super-large scale panel bottom structure is designed as an integral interconnected structure, and the local structural damage caused by the above problems such as cumulative blasting vibration, stress concentration, and filling body settlement deformation can quickly spread across the region through the interconnected roadway, not only leading to a decrease in the efficiency of the damaged area, but also endangering the bottom structure of the adjacent stope, causing the difficulty of repairing the bottom structure to increase dramatically, and even interrupting the production of the entire panel.

[0030] Therefore, how to solve the problems of insufficient stability and local damage chain diffusion of the super-large scale panel bottom structure under the complex stress and multi-factor coupling has become a problem of ensuring safe and efficient mining in deep mines.

[0031] To solve the above technical problems, the application provides a distributed rigid-flexible coupling bottom structure construction method, referring to Figures 1 to 5 , comprising: S10, arranging the preparation engineering in the super-large scale panel bottom structure; the purpose of this step is to construct the foundation engineering system for subsequent mining operations, such as development roadway, stope connecting roadway, ore receiving roadway, and ore outlet roadway, to provide a channel for subsequent pre-splitting blast hole construction, stope mining, ore transportation, and personnel and equipment passage, and to clearly define the boundaries of the one-step and two-step stope to plan the spatial range for step-by-step mining; at the same time, auxiliary systems such as ventilation, drainage, and power supply are established in advance to ensure the continuity and safety of subsequent operations.

[0032] For example, the upper panel along-vein transportation roadway 2 and the lower panel along-vein transportation roadway 16 are constructed as the main channel for ore transportation and personnel and equipment passage in the panel; at the same time, the panel through-vein connecting roadway 17 is constructed to connect the upper and lower panel along-vein transportation roadways, forming a horizontal connecting network of the panel and clearly defining the overall boundary range of the panel.

[0033] Based on the development engineering, the one-step stope ore receiving roadway 18 and the two-step stope ore receiving roadway 20 are constructed in sequence to receive the ore from the stope; at the same time, the ore outlet roadway 4 is constructed as a channel for ore transfer; then the one-step stope ore outlet access 19 and the two-step stope ore outlet access 21 are constructed to connect the ore receiving roadway and the ore outlet roadway, forming an ore transfer path; in addition, the off-vein connecting roadway 12 is constructed to realize the personnel, equipment, and ventilation connection between different stope.

[0034] The construction panel area chute 1 connects the mining roadway and the external transportation system, and improves the ore transfer efficiency. The construction return air shaft 6 cooperates with the along-vein transportation roadway and the vein outside connecting roadway to construct a ventilation system. Meanwhile, the drainage pipeline, power supply line and other supporting facilities are arranged, which cooperates with the roadway engineering to form a complete panel bottom structure engineering system, and meets the operation requirements of subsequent pre-splitting blasting and stope mining.

[0035] S20, in the ultra-large panel bottom structure, pre-splitting blast holes are arranged along the trend of the ore body to be mined; the purpose of this step is to preset the hole position for controllable pre-splitting blasting, to ensure that a spaced pre-splitting space can be formed in the trend of the ore body, which is beneficial to the division of the whole peach-shaped pillar into multiple independent units.

[0036] For example, the holes are arranged along the extension direction of the ore outlet roadway 4 in the bottom structure 22, to ensure that the trend of the pre-splitting blast hole 9 is consistent with the trend of the ore body to be mined, and to lay a foundation for the subsequent formation of a pre-splitting space 8 distributed along the trend of the ore body.

[0037] In the region of the ore body between the stope receiving roadway 18 of the first step and the stope receiving roadway 20 of the second step, the pre-splitting blast holes 9 are arranged according to the spacing requirements, and the region is the formation range of the subsequent peach-shaped pillar 7. The spacing of the holes can plan the pillar division unit in advance.

[0038] When arranging the holes, the core bearing section of the stope outlet approach 19 of the first step, the stope outlet approach 21 of the second step and the receiving roadway are avoided, to ensure that the hole position of the pre-splitting blast hole 9 does not affect the main stability of the bottom structure 22, and to reserve a safe operation space for the subsequent pre-splitting blasting.

[0039] The hole position of each pre-splitting blast hole 9 corresponds to the central region of the subsequent pre-splitting space 8 to be formed, to ensure that the pre-splitting space can be accurately formed after blasting, and to make good hole position preset for the subsequent division of the whole peach-shaped pillar.

[0040] S30, pre-splitting blasting is performed to form a pre-splitting space, which is located in the peach-shaped pillar, and the two peach-shaped pillars containing the pre-splitting space are not adjacent. This step is to cut off the stress transmission path of the pre-splitting space which cuts off the continuous ore body, to realize the physical division of the pillar region in advance, to block the stress transmission from the surrounding rock mass to the subsequent peach-shaped pillar region, and to avoid the instability and damage of the pillar due to stress concentration.

[0041] For example, staggered uncoupled charging is used in the arranged pre-splitting blast hole 9, to ensure that the explosive energy is uniformly transmitted to the hole wall rock mass, and to avoid excessive charging density which may cause excessive blasting impact force, to protect the main components such as the ore outlet roadway 4 and the receiving roadway of the bottom structure 22 from being damaged.

[0042] Take the interval distribution of pre-splitting blast hole 9 as the benchmark, start the blasting operation in batches, and each batch of blasting is adjacent to 1-2 pre-splitting blast holes 9, which ensures that the blasting energy is concentrated on the current hole position rock mass, accurately forms an independent pre-splitting space 8, and avoids excessive fragmentation of the rock mass caused by multi-hole simultaneous blasting.

[0043] During the blasting process, the buffer layer at the boundary of the pre-splitting blast hole 9 hole bottom and the bottom structure 22 is strictly controlled to ensure that the blasting only forms a pre-splitting space 8 in the area of the ore body to be mined, does not affect the bearing section of the step 2 stope ore roadway 20, and maintains the overall stability of the bottom structure.

[0044] Through the above blasting operation, a pre-splitting space 8 corresponding to the hole position is formed at the position of the pre-splitting blast hole 9 along the ore body trend, and each pre-splitting space 8 is distributed at the formation area of the subsequent peach-shaped ore pillar 7 according to the preset interval, which realizes the physical cutting of the continuous ore body and provides a spatial basis for subsequent segmentation of the peach-shaped ore pillar 7 into independent units.

[0045] S40, stoping the step 1 stope, and forming the inclined surface of the peach-shaped ore pillar on one side in the ore body by constructing an inclined hole and blasting; as the first stage of step-by-step stoping, part of the ore body is mined first to realize resource recovery, and the inclined surface of the peach-shaped ore pillar on one side is formed by means of inclined hole blasting.

[0046] For example, taking the step 1 stope ore roadway 18 as the bottom operation benchmark and using the segmented rock drilling roadway 24 as the rock drilling operation channel, it ensures that personnel and equipment can enter the operation area through the vein external connecting roadway 12, and at the same time, the return air shaft 6 ensures the ventilation of the stope, providing a safe operation environment for the stoping blasting.

[0047] Construct upward fan-shaped blast holes 23 in the segmented rock drilling roadway 24, which cover the area of the ore body to be mined in the step 1 stope; after blasting, the ore falls into the step 1 stope ore roadway 18 by its own gravity, and then is transported to the ore drawing roadway 4 through the step 1 stope ore drawing access 19, completing the ore recovery of the step 1 stope.

[0048] At the boundary of the step 1 stope close to the subsequent peach-shaped ore pillar 7, the inclined hole 26 of the peach-shaped ore pillar is constructed along the preset inclination angle; after the construction of the inclined hole is completed, directional blasting is carried out, and after blasting, an inclined surface is formed in the ore body which is adapted to the profile of one side of the peach-shaped ore pillar 7, and at the same time, the inclined short blast hole is constructed to form the ore falling groove 27 in the area adjacent to the inclined surface of the step 1 stope ore roadway 18, ensuring that the subsequent ore can flow smoothly into the ore roadway.

[0049] S50, Construct an arched filling retaining wall at the pre-splitting space formed in the ore drawing roadway of the peach-shaped pillar, and at the same time, set an additional retaining wall at the intersection section of the one-step stope and the two-step stope ore drawing roadway, and then fill the goaf of the one-step stope; maintain the ore drawing roadway in the peach-shaped pillar through the filling retaining wall, so as to prevent the slurry from invading the ore drawing roadway of the peach-shaped pillar through the gap of the pre-splitting space in the filling operation, and form an interval filling body cushion layer in the peach-shaped pillar.

[0050] For example, at the pre-splitting space 8 in the ore drawing roadway 4 corresponding to the peach-shaped pillar 7, an arched filling retaining wall 10 is built to ensure that the retaining wall completely covers the opening area of the pre-splitting space 8, blocks the subsequent filling slurry from invading the ore drawing roadway 4 through the gap of the pre-splitting space 8, and at the same time, uses the arched structure to improve the impact resistance of the retaining wall itself and adapt to the filling pressure.

[0051] At the intersection section of the one-step stope ore drawing roadway 18 and the two-step stope ore drawing roadway 20, a two-step stope ore drawing filling retaining wall 31 (additional retaining wall) is installed to form double protection, avoid the overflow of filling slurry from the intersection gap of the two ore drawing roadways, and at the same time, protect the structural integrity of the intersection section of the roadway.

[0052] Through the segmented drilling roadway 24 or a special filling pipeline, filling material is injected into the goaf formed after the one-step stope is mined, until the top surface of the filling body is flush with the roof of the stope, forming a one-step stope filling body 28; the sealing property of the retaining wall is monitored during the filling process to ensure that the slurry does not leak into the ore drawing roadway 4 or the two-step stope area, and finally an interval filling body cushion layer is formed in the peach-shaped pillar 7 under the cooperation of the pre-splitting space 8 and the retaining wall.

[0053] S60, After the one-step stope filling body reaches the designed strength and is fully consolidated, the two-step stope mining operation is carried out, and at the same time, the inclined surface on the other side of the peach-shaped pillar is formed by constructing an inclined hole and blasting, thereby forming the peach-shaped pillar. The continuous bottom structure is separated into multiple independent units by the interval pre-splitting space, forming a distributed pillar group, avoiding the overall damage caused by the excessive stress on a single pillar, and each unit independently supports, further improving the overall stability of the bottom structure.

[0054] For example, the strength of the one-step stope filling body 28 is verified by a detection device, and after it reaches the design requirements and is fully consolidated, the two-step stope mining preparation is started to ensure that the subsequent operation does not damage the formed filling body and retaining wall structure.

[0055] Taking the two-step stope ore drawing roadway 20 as the operation reference, the upward fan-shaped blast hole 23 is constructed in the segmented drilling roadway 24 (the arrangement logic is consistent with that of the one-step stope), covering the ore body area of the two-step stope to be mined 25; after blasting, the ore is transported to the ore drawing roadway 4 through the two-step stope ore drawing roadway 20 and the two-step stope ore drawing approach 21, and the resource recovery of the two-step stope is completed.

[0056] At the boundary of the two-step stope close to the peach-shaped pillar 7, the inclined hole 26 forming the peach-shaped pillar is constructed at an angle matched with the inclined hole of the one-step stope; through directional blasting, the inclined surface of the other side of the peach-shaped pillar 7 is formed in the ore body, and the inclined surface formed in the S40 step forms a complete peach-shaped contour together.

[0057] The interval pre-splitting space 8 formed in the previous S30 step is used to divide the continuous ore body bottom into multiple independent units, each unit is isolated from each other through the pre-splitting space 8, and a distributed pillar group is formed, that is, the bottom structure 22 is formed, so as to avoid that a single unit is subjected to excessive stress and causes overall damage.

[0058] In this example, the peach-shaped pillar 7 and other filling bodies form a rigid bearing part to bear the main load and resist overall instability of the structure; the pre-splitting space 8 forms a flexible stress relief part to absorb local deformation and block stress transmission. The traditional bottom structure is continuous and integral, and once local stress concentration or damage occurs, it will quickly spread through the connected roadway. The pre-splitting space gives the system the ability to flexibly relieve stress by actively creating a physical gap. When the surrounding rock transmits the maximum principal stress, the pre-splitting space can block the continuous transmission of stress: when the stress reaches the pre-splitting space, it will be greatly attenuated due to the lack of rock bearing in the interval, and cannot be transmitted to the peach-shaped pillar or the bottom structure of the adjacent unit, solving the problem of structure damage caused by stress concentration. When the filling body produces slight settlement due to subsidence, the gap of the pre-splitting space can provide a certain deformation allowance, and the settlement deformation is only limited within the current unit and cannot be transmitted to other units through the continuous structure, avoiding that local deformation causes overall instability.

[0059] The particularity of the pre-splitting space 8 being placed in the peach-shaped pillar 7 is that the peach-shaped pillar is a stress concentration area in the bottom structure, and the pre-splitting space is placed in the peach-shaped pillar to relieve the excessive stress in the peach-shaped pillar, thereby maintaining the integrity of the bearing structure of the peach-shaped pillar and avoiding instability of the bearing structure caused by stress concentration.

[0060] The two peach-shaped pillars containing the pre-splitting space are not adjacent, which means that there is at least one complete peach-shaped pillar between the two peach-shaped pillars with the pre-splitting space. The peach-shaped pillar with the pre-splitting space has the advantage of having a certain load release capacity, but the shortcoming is that the bearing stiffness is slightly weak; the complete peach-shaped pillar has the advantage of strong bearing stiffness, but the shortcoming is that it will completely absorb stress and cause cracking. Through the design of spacing at least one complete pillar, the advantages of the two can be complementary, which is beneficial to the formation of the rigid and flexible coupling bottom structure.

[0061] The application provides a distributed rigid and flexible coupling bottom structure construction method, which comprises: S10, arranging the mining and preparation engineering in the bottom structure of the super-large scale panel; S20, in the super-large scale panel bottom structure, pre-splitting blast holes are arranged along the trend of the ore body to be mined at intervals; S30, pre-splitting blasting is performed to form a pre-splitting space; S40, the step 1 stope is recovered, and an inclined surface of one side of the peach-shaped ore pillar is formed in the ore body by means of construction of an inclined hole and blasting; S50, an arched filling retaining wall is constructed at the pre-splitting space formed in the peach-shaped ore pillar recovery roadway, and an additional retaining wall is arranged at the intersection of the step 1 stope and the step 2 stope recovery roadway, and then the step 1 stope goaf is filled; S60, after the step 1 stope filling body reaches the designed strength and is fully consolidated, the step 2 stope recovery operation is carried out, and an inclined surface of the other side of the peach-shaped ore pillar is formed by means of construction of an inclined hole and blasting, so as to form the peach-shaped ore pillar.

[0062] By actively cutting off the stress transmission path of the rock mass through the pre-splitting space, the continuous bottom structure is divided into independent units, thereby solving the problems of maximum principal stress concentration and blast vibration accumulation and conduction. On the other hand, the step-by-step recovery is combined with the formation of the peach-shaped ore pillar, and the filling body formed in combination with the double retaining walls, to form a rigid-soft coupling system of rigid ore pillar bearing combined with flexible interval unloading, which not only resists the structural deformation caused by the settlement of the filling body, but also avoids the chain diffusion of local damage, and solves the core problems of insufficient stability of the bottom structure and easy interruption of production in the traditional method.

[0063] In some embodiments, with reference to Figure 1 , the preparation engineering includes, on the basis of the development engineering such as the upper-vein transportation roadway on the middle section, the lower-vein transportation roadway and the vein-passing roadway in the panel, the ore receiving roadway, the ore recovery roadway and the ore recovery access are sequentially constructed to form a complete panel bottom structure engineering system.

[0064] For example, on the basis of the development engineering such as the upper-vein transportation roadway 2, the lower-vein transportation roadway 16 and the vein-passing roadway 17 in the panel, the step 1 stope ore receiving roadway 18 and the step 2 stope ore receiving roadway 20 are sequentially constructed, and then the ore recovery roadway 4 is simultaneously constructed, and finally the step 1 stope ore recovery access 19 and the step 2 stope ore recovery access 21 are further constructed, so that the ore receiving roadway, the ore recovery roadway and the ore recovery access are connected to each other to form a complete panel bottom structure engineering system.

[0065] At the same time, the vein external connecting roadway 12, the panel chute 1 and the air return raise 6 are constructed in combination with the mining requirements of the panel.

[0066] In some embodiments, with reference to Figure 2 , the cross-sectional size of the ore receiving roadway, the ore recovery roadway and the ore recovery access needs to meet the ore recovery and ventilation requirements and provide operation space for subsequent pre-splitting blasting operations.

[0067] In some embodiments, with reference toFigure 2 The pre-splitting blast hole is arranged along the direction in which the ore drawing tunnel of the bottom structure extends, and a buffer layer is reserved between the bottom of the pre-splitting blast hole and the boundary of the bottom structure; the buffer layer is used to avoid damage to the main body of the bottom structure caused by pre-splitting blasting, so as to accurately control the blasting influence range.

[0068] For example, the pre-splitting blast hole 9 is arranged continuously along the direction in which the ore drawing tunnel 4 of the bottom structure extends, and a certain thickness of rock mass is reserved as a buffer layer between the bottom of each pre-splitting blast hole and the boundary of the bottom structure, for example, 1 meter thick rock mass is reserved as a buffer layer. The buffer layer can absorb part of the energy of pre-splitting blasting, avoid the direct action of the blasting shock wave on the main body of the bottom structure, prevent the cracking or deformation of the tunnel wall of the ore drawing tunnel and the ore drawing tunnel, protect the integrity of the bottom structure 22, and ensure that the pre-splitting space 8 is formed only inside the peach-shaped ore pillar 7, without affecting the surrounding ore drawing access.

[0069] In some embodiments, with reference to Figure 2 For example, during pre-splitting blasting, staggered uncoupling charging structure is used in the pre-splitting blast hole 9, that is, a gap is left between the explosive and the blast hole wall, and the charging positions of adjacent blast holes are staggered and not aligned in a straight line. Uncoupling charging can reduce the impact pressure of blasting on the hole wall, reduce the degree of crushing of the ore pillar rock mass, ensure the smoothness of the boundary of the pre-splitting space 8, and avoid the formation of irregular cracks; staggered arrangement can uniformly distribute the blasting energy, ensure the accurate formation of the pre-splitting space 8 along the designed direction, and reduce the disturbance to adjacent ore pillar units.

[0070] In some embodiments, with reference to Figure 4 For example, during one-step stope mining, upward fan-shaped medium-length holes are drilled in the upper section of the drill hole and the bottom ore receiving tunnel, and inclined short blast holes are drilled near the stope boundary of the ore receiving tunnel; the inclined short blast holes are used to form ore falling grooves to improve the flowability of the ore and the efficiency of ore drawing. For example, during one-step stope mining, the blast holes are drilled in two steps: upward fan-shaped medium-length holes are drilled in the upper section of the drill hole, and inclined downward short blast holes are drilled near the stope boundary of the one-step stope ore receiving tunnel 18. After the blasting of the inclined short blast holes, the ore falling grooves 27 are formed.

[0071] In some embodiments, with reference to Figure 4 For example, during one-step stope mining, the medium-length holes are blasted in a row-by-row differential initiation mode; a differential delay is set between each row of blast holes; the row-by-row differential initiation can control the blasting vibration intensity, avoid the strong shock wave generated by the simultaneous initiation of multiple rows of blast holes from damaging the bottom structure or the peach-shaped ore pillar 7; the blasting of the subsequent row of blast holes can form a squeezing effect on the ore blasted by the previous row of blast holes, promote the crushing of the ore, and at the same time avoid the ore from splashing too far, thereby improving the blasting safety and the quality of ore crushing.

[0072] In some embodiments, referring to Figure 1 , 2 , 4, a preset number of blast holes are initiated each time, the blast holes in the row are sequentially initiated in at least two segments by differential delay, and delay blasting is used between rows. For example, during the stoping blasting, only a preset number of blast holes are initiated each time; the blast holes in the same row are sequentially initiated in at least two segments by differential delay; and a delay interval is also set between different rows. By controlling the single-segment initiation explosive charge, the peak value of the blasting vibration is further reduced, and the pre-splitting space 8 and the bottom structure 22 are protected from impact. The segmented initiation in the row can avoid the formation of large blocks caused by the mutual extrusion of ores in the same row. The delay between rows can reserve time for the ore to fall, prevent the one-step stope ore drawing passage 19 from being blocked, and improve the continuity of ore drawing.

[0073] In some embodiments, referring to Figure 3 and Figure 5 , while the arch-shaped filling retaining wall is constructed, an additional retaining wall is arranged at the intersection section of the one-step stope and the two-step stope ore receiving roadway. For example, after the one-step stope is mined, the arch-shaped filling retaining wall 10 is constructed, and an additional retaining wall, i.e., the two-step ore receiving roadway filling retaining wall 31, is additionally arranged at the intersection section of the one-step stope ore receiving roadway 18 and the two-step stope ore receiving roadway 20. The arch-shaped filling retaining wall bears the main pressure of the filling body, and the additional retaining wall serves as a secondary protection to prevent the filling body from leaking from the gap between the two ore receiving roadways, thereby avoiding the blockage of the ore receiving roadways or the pollution of the two-step stope. The intersection section is a stress concentration area, and the additional retaining wall can enhance the structural stability of this part to provide a safe boundary for the two-step stope mining.

[0074] In some embodiments, referring to Figure 1 and Figure 4 , the arrangement logic of the upward fan-shaped medium-length hole and the inclined short blast hole for forming the ore falling groove during the two-step stope mining is consistent with that of the one-step stope; and when the inclined hole is constructed to form the other inclined surface of the peach-shaped ore pillar, the construction direction of the inclined hole is adapted to the inclined hole for forming one inclined surface of the peach-shaped ore pillar in the one-step stope. For example, during the two-step stope mining, the arrangement logic of the upward fan-shaped medium-length hole and the inclined short blast hole at the two-step stope ore receiving roadway 20 is completely consistent with that of the one-step stope. When the inclined hole is constructed to form the other inclined surface of the peach-shaped ore pillar 7, the construction direction of the inclined hole is adapted to the inclined hole for forming the other inclined surface of the ore pillar in the one-step stope. The consistent hole arrangement logic can reduce the construction difficulty, ensure the consistency of the mining efficiency and ore recovery rate of the two-step stope, and the adaptation of the inclined hole direction can ensure the precise butt joint of the two inclined surfaces of the peach-shaped ore pillar 7 to form a complete peach-shaped load-bearing structure, avoid stress concentration caused by irregular ore pillar shape, and improve the load-bearing stability of the ore pillar.

[0075] The above merely describes specific embodiments of the present application, but the protection scope of the present application is not limited thereto, and any modification, equivalent replacement, and improvement within the technical range disclosed by the present application and within the spirit and principle of the present application should be encompassed within the protection scope of the present application.

[0076] Note that the present application is not limited to the above-described embodiments. The above-described embodiments are merely examples, and embodiments having substantially the same configuration and exerting the same effects as the technical idea within the technical scope of the present application are also included in the technical scope of the present application. Furthermore, other modes constructed by applying various modifications to the embodiments or combining part of the configuration elements of the embodiments that a person skilled in the art can conceive within the scope of the gist of the present application are also included in the scope of the present application.

Claims

1. A method for constructing a distributed rigid-flexible coupled bottom structure, characterized in that, The application relates to a method for constructing a large-scale panel bottom structure and a method for mining a large-scale panel. The method comprises the following steps: arranging mining preparation engineering in a large-scale panel bottom structure; arranging pre-splitting blast holes in the large-scale panel bottom structure along the trend of a to-be-mined ore body; performing pre-splitting blasting to form a pre-splitting space, which is located in a peach-shaped pillar, and two peach-shaped pillars containing the pre-splitting space are not adjacent; mining a one-step stope and forming an inclined surface of one side of the peach-shaped pillar by means of construction and blasting in the ore body; constructing an arched filling retaining wall at the pre-splitting space formed in a peach-shaped pillar mining roadway, and arranging an additional retaining wall at a junction section of the one-step stope and a two-step stope receiving roadway, and then filling the one-step stope goaf; after the one-step stope filling body reaches the designed strength and is fully consolidated, carrying out two-step stope mining operation, and forming an inclined surface of the other side of the peach-shaped pillar by means of construction and blasting, so as to form the peach-shaped pillar. The mining preparation engineering comprises the following steps: on the basis of development engineering such as an upper panel along-vein transportation roadway, a lower panel along-vein transportation roadway and a panel through-vein roadway, sequentially constructing a receiving roadway, a mining roadway and a mining access to form a complete panel bottom structure engineering system. The section size of the receiving roadway, the mining roadway and the mining access needs to meet the requirements of ore drawing and ventilation, and provide operation space for subsequent pre-splitting blasting operation. The pre-splitting blast holes are arranged along the extension direction of the mining roadway of the panel bottom structure, and a buffer layer is reserved between the bottom of the pre-splitting blast hole and the boundary of the panel bottom structure; the buffer layer is used to avoid damage to the main body of the panel bottom structure caused by pre-splitting blasting, so as to accurately control the blasting influence range. The pre-splitting blasting adopts an interlaced uncoupled charging structure. During one-step stope mining, upward fan-shaped medium-length holes are drilled in the stope section and the receiving roadway of the panel bottom structure, and inclined short blast holes are drilled near the stope boundary of the receiving roadway; the inclined short blast holes are used to form a falling ore chute to improve the ore flowability and ore drawing efficiency.

2. The method of claim 1, wherein, The blasting of the one-step stope adopts a medium-length hole row-by-row millisecond initiation mode.

3. The method of claim 2, wherein, Each time, a preset number of blast holes are initiated, the blast holes in the row are divided into at least two sections and sequentially initiated by millisecond delay, and the delay blasting is adopted between the rows.

4. The method of claim 1, wherein, The arched filling retaining wall is constructed, and an additional retaining wall is arranged at the junction section of the one-step stope and the two-step stope receiving roadway.

5. The method of claim 4, wherein, During two-step stope mining, the arrangement logic of the upward fan-shaped medium-length holes and the inclined short blast holes for forming a falling ore chute is consistent with that of the one-step stope; and when the inclined holes are drilled to form the inclined surface of the other side of the peach-shaped pillar, the drilling direction of the inclined holes is matched with that of the inclined holes drilled to form the inclined surface of one side of the peach-shaped pillar of the one-step stope.

6. The method of claim 1, wherein, ​ 7. The method of claim 5, wherein, ​ 8. The method of claim 7, wherein, ​ 9. The method of claim 1, wherein, ​ 10. The method of claim 1, wherein, ​

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