A full-face grouting supporting structure for a strong pressure roadway

Abstract

The utility model discloses a whole section grouting support structure for strong mine pressure roadway belongs to mine roadway support technical field. The structure includes roof support subassembly and two side support subassembly, the roof support subassembly includes grouting anchor cable arranged in the roadway roof with predetermined interval spacing, the two side support subassembly includes grouting anchor rod arranged in the roadway two sides with predetermined interval spacing, grouting anchor cable and grouting anchor rod are all configured to the pressure grouting in the surrounding country rock can be carried out, make the roof support subassembly with two side support subassembly constitute a whole section grouting reinforcement structure of integral whole. The utility model forms the "reinforced concrete" formula structure of collaborative loading with anchor rod, anchor cable through grouting and breaks up the surrounding rock cement to the whole, has improved the integrity and strength of support system significantly, has effectively controlled the roof subsidence and two side side drum of strong mine pressure roadway, has solved the difficult problem of traditional support in the broken surrounding rock effect is not good.

Description

Technical Field

[0001] This utility model relates to the field of mine roadway support technology, and more specifically to a full-section grouting support structure for roadways under heavy mining pressure. Background Technology

[0002] In coal mining, the stability of the surrounding rock in roadways is directly related to the mine's safe production and operational efficiency. For roadways located in areas with high ground stress and complex geological structures, often characterized by "strong mine pressure," the surrounding rock is usually quite fractured and has poor self-stabilizing ability.

[0003] Specifically, the existing technology has the following prominent problems:

[0004] Insufficient overall support system: Traditional anchor bolts and cables mainly rely on their rods to provide axial restraint, which is difficult to effectively suppress the development of cracks and delamination in the surrounding rock.

[0005] Insufficient improvement of fractured surrounding rock: In fractured roof or sidewalls, the anchoring force of anchor bolts is difficult to guarantee, and their anchoring section may be located in the fractured rock mass, which cannot effectively inhibit the further development of surrounding rock fissures, leading to support failure.

[0006] Failure to form a coordinated load-bearing structure: The roof support and the sidewall supports are relatively independent, failing to form a unified full-section pressure-bearing structure. When the roadway is subjected to strong mining pressure, the roof subsidence and the sidewall heave exacerbate each other, easily forming a vicious cycle and leading to the overall instability of the support structure.

[0007] Therefore, how to provide a full-section grouting support structure for roadways under heavy mining pressure that can significantly improve the bearing capacity of the surrounding rock, enhance the integrity of the support system, and effectively control the deformation of roadways under heavy mining pressure is a problem that urgently needs to be solved by those skilled in the art. Utility Model Content

[0008] In view of this, the present invention provides a full-section grouting support structure for roadways under heavy mining pressure.

[0009] To achieve the above objectives, this utility model provides the following technical solution:

[0010] A full-section grouting support structure for roadways under heavy mining pressure, characterized in that it includes: a roof support assembly and two side support assemblies;

[0011] The roof support assembly consists of multiple grouting anchor cables arranged at a predetermined interval on the roof of the roadway, and the side support assembly consists of multiple grouting anchor bolts arranged at a predetermined interval on the two sides of the roadway.

[0012] The grouting anchor cable and the grouting anchor rod are both configured to perform pressure grouting into the surrounding rock, so that the roof support assembly and the two side support assemblies together form an integral full-section grouting reinforcement structure.

[0013] Preferably, the grouting anchor cable is a steel strand anchor cable.

[0014] Preferably, the grouting anchor is a left-hand threaded steel anchor without longitudinal reinforcement.

[0015] Preferably, the grouting anchor cable and grouting anchor rod are both full-length anchored.

[0016] As can be seen from the above technical solution, compared with the prior art, the full-section grouting support structure for roadways under heavy mining pressure disclosed in this utility model has the following significant beneficial effects:

[0017] This invention achieves full-section coordinated active reinforcement: By simultaneously grouting the roadway roof (using grouting anchor cables) and both sides (using grouting anchor rods), the originally independent roof support structure and side support structure are mechanically integrated into an organic whole. Under pressure, the grout penetrates and cements the surrounding rock fissures throughout the roadway cross-section, forming a unified "reinforcement ring" that jointly resists external mining pressure, significantly improving the overall stability and coordinated load-bearing capacity of the support system.

[0018] The deformation of the surrounding rock was greatly controlled: through numerical simulation verification, the full-section grouting scheme of this utility model reduced the maximum deformation of the roadway roof by 228mm and the maximum deformation of the sidewalls by 219mm compared with the original support. The deformation of the roof was reduced by 23% and the deformation of the sidewalls was reduced by 27% compared with the existing support conditions. This effectively controlled the shrinkage of the roadway cross section, ensured the space required for safe production such as ventilation and transportation, and extended the service life of the roadway. Attached Figure Description

[0019] To more clearly illustrate the technical solutions in the embodiments of this utility model or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only embodiments of this utility model. For those skilled in the art, other drawings can be obtained based on the provided drawings without creative effort.

[0020] Figure 1 The attached figure is a schematic diagram of the grouting support structure of the top slab anchor cable and the two side anchor bolts of this utility model.

[0021] Figure 2 The attached figure is a schematic diagram of the extended anchoring structure of the grouting anchor cable of this utility model.

[0022] Figure 3The attached figure is a schematic diagram of the working principle of the composite beam of this utility model. Detailed Implementation

[0023] The technical solutions of the present utility model will be clearly and completely described below with reference to the accompanying drawings of the embodiments. Obviously, the described embodiments are only some embodiments of the present utility model, and not all embodiments. Based on the embodiments of the present utility model, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the protection scope of the present utility model.

[0024] like Figures 1 to 3 As shown, this embodiment provides a full-section grouting support structure for roadways under heavy mining pressure;

[0025] The full-section grouting support structure for roadways under heavy mining pressure specifically includes: a roof support component 10 and two side support components 20.

[0026] The roof support assembly 10 consists of multiple grouting anchor cables 1 arranged on the roadway roof at a predetermined spacing. Specifically, the grouting anchor cables 1 are 22mm diameter steel strand anchor cables with a length of 6.3m to ensure that their anchoring section can penetrate deep into the stable rock strata of the roof. The spacing between the roof grouting anchor cables 1 is 1.5m to 2.0m, with a preferred spacing of 1.6m and a preferred row spacing of 2.0m, with three cables arranged in each row.

[0027] The two-side support assembly 20 consists of multiple grouting anchor bolts 2 arranged at predetermined intervals on both sides of the roadway. Specifically, the grouting anchor bolts 2 are left-handed threaded steel anchor bolts without longitudinal reinforcement, with a diameter of 22mm and a length of 2.4m. The interval between rows of the grouting anchor bolts 2 on both sides is 0.8m to 1.0m, with a preferred spacing of 0.9m and a preferred row spacing of 0.9m, with five bolts arranged in each row.

[0028] To form an effective full-section synergistic support, the grouting anchor cable 1 on the top slab and the grouting anchor rods 3 on both sides are connected to the grouting pump through grouting pipelines, enabling high-pressure injection of grout into the gaps between the borehole and the surrounding rock, as well as into the surrounding fissures. After the grout solidifies, it not only forms a wider reinforcement ring outside the anchoring agent, but also mechanically connects the support components of the top slab and both sides into a whole, jointly constituting a full-section grouting reinforcement structure.

[0029] By injecting grout into the borehole, the grout penetrates into the pores and fractures of the surrounding strata under pressure. For fractured and loose rock and soil masses, the solidified grout binds these loose particles together, increasing the cohesion and internal friction angle of the rock and soil mass, thereby improving its overall strength and stability. In coal mine roadways, grouting can effectively improve the cohesion, internal friction angle, and elastic modulus of fractured coal and rock masses, preventing roadway deformation and collapse.

[0030] Furthermore, such as Figure 2 As shown, during the initial installation, the grouting anchor cable 1 is pre-tensioned using a tensioning device. After a short delay, the grouting continues, filling the anchor cable holes with grout, transforming the end anchoring into full-length anchoring. This improves the anchor cable's stress distribution and sensitivity to delamination, and also resists shear deformation of the rock strata. Grouting and the anchor cable together inhibit crack propagation and delamination, forming a surrounding rock anchoring layer and a grouting layer that jointly bear the load, further enhancing the stability of the roof. Similar to reinforced concrete, the grouting anchor cable 1 acts as reinforcement; after the grout diffuses and solidifies, the fractured rock mass forms a unified whole, acting as concrete. Without reinforcement of the fractured rock mass, the anchor cable cannot function effectively on the fractured, loose roof. Practice shows that after reinforcing the fractured roof with grouting anchor cable 1, the strength is higher than the original roadway roof, allowing it to adapt to large deformations in soft rock.

[0031] Simultaneously, a metal mesh and W-shaped steel strip are laid on the surface of the tunnel. The metal mesh and W-shaped steel strip are tightly pressed against the surrounding rock surface by the anchor at the end of the grouting anchor cable 1 and the nut at the end of the grouting anchor rod 2, which plays a role in protecting the surface and controlling the shallow surrounding rock in the initial stage of support.

[0032] During construction, the top slab grouting anchor cables 1 and the two side grouting anchor rods 2 were first installed according to the design parameters, and pre-tightened. Then, high-pressure grouting was performed across the entire cross-section through the grouting pipes embedded in the anchor cables and anchor rods. Under pressure, the grout penetrated into the cracks in the top slab and the two side slabs.

[0033] For the roof: Grouting binds the broken roof coal and the rock mass at the coal-rock interface into a whole, forming a "composite beam" structure that combines the "grouting reinforcement ring" and the "anchor cable skeleton", which greatly improves the integrity and bearing capacity of the roof.

[0034] For the two sides: Grouting strengthens the cohesion and internal friction angle of the coal and rock mass in the side, so that the function of the grouting anchor 2 changes from simple suspension to overall reinforcement of the surrounding rock of the side, effectively inhibiting the bulging of the side and the expansion of the plastic zone.

[0035] Specifically, the principle of composite beam theory is as follows: When excavating a tunnel in a deeply buried rock mass with a layered structure, if there is no hard and stable rock mass within the tunnel roof area, the suspension function of the anchor bolts on the roof rock mass is secondary. In a layered rock mass, each layer of rock has its corresponding cohesion and internal friction angle; however, the bonding force and interlocking effect between the rock layers are very weak. Without the action of anchor bolts and cables, the layered roof rock mass in this area of ​​the tunnel forms a corresponding composite beam structure. Under the action of surrounding rock stress, this causes the layered roof rock mass to slide and delaminate, a situation that is highly prone to roof collapse accidents. However, after reinforcing the surrounding rock with anchor bodies, the layered roof rock mass forms a composite beam structure, which greatly increases the strength of the surrounding rock and improves its stability. Figure 3 As shown.

[0036] Compared with existing technologies, the full-section grouting support structure for roadways under heavy mining pressure provided by this utility model has the following significant advantages:

[0037] This invention achieves full-section coordinated active reinforcement: By simultaneously grouting the roadway roof (using grouting anchor cables) and both sides (using grouting anchor rods), the originally independent roof support structure and side support structure are mechanically integrated into an organic whole. Under pressure, the grout penetrates and cements the surrounding rock fissures throughout the roadway cross-section, forming a unified "reinforcement ring" that jointly resists external mining pressure, significantly improving the overall stability and coordinated load-bearing capacity of the support system.

[0038] The deformation of the surrounding rock was greatly controlled: through numerical simulation verification, the full-section grouting scheme of this utility model reduced the maximum deformation of the roadway roof by 228mm and the maximum deformation of the sidewalls by 219mm compared with the original support. The deformation of the roof was reduced by 23% and the deformation of the sidewalls was reduced by 27% compared with the existing support conditions. This effectively controlled the shrinkage of the roadway cross section, ensured the space required for safe production such as ventilation and transportation, and extended the service life of the roadway.

[0039] The above description of the disclosed embodiments enables those skilled in the art to make or use the present invention. Various modifications to these embodiments will be readily apparent to those skilled in the art, and the general principles defined herein may be implemented in other embodiments without departing from the spirit or scope of the present invention. Therefore, the present invention is not to be limited to the embodiments shown herein, but is to be accorded the widest scope consistent with the principles and novel features disclosed herein.

Claims

1. A full-section grouting support structure for roadways under heavy mining pressure, characterized in that, include: Top plate support assembly (10), side plate support assembly (20); The roof support assembly (10) consists of multiple grouting anchor cables (1) arranged on the roof of the roadway at a predetermined spacing, and the side support assembly (20) consists of multiple grouting anchor bolts (2) arranged on the two sides of the roadway at a predetermined spacing. The grouting anchor cable (1) and the grouting anchor rod (2) are both configured to perform pressure grouting into the surrounding rock, so that the top plate support assembly (10) and the two side support assemblies (20) together form an integral full-section grouting reinforcement structure. The grouting anchor cable (1) is a steel strand anchor cable; The grouting anchor (2) is a left-hand threaded steel anchor without longitudinal reinforcement; The grouting anchor cable (1) and grouting anchor rod (2) are both of the full-length anchoring type; The grouting anchor cable (1) is a steel strand anchor cable with a diameter of 22mm and a length of 6.3m. The spacing between the top slab grouting anchor cables (1) is 1.5m to 2.0m, with three anchor cables arranged in each row. The grouting anchor rod (2) is a left-hand threaded steel anchor rod with a diameter of 22mm and a length of 2.4m. The spacing between the two sides grouting anchor rods (2) is 0.8m to 1.0m, with five anchor rods arranged in each row. It also includes a metal mesh and W-steel strip laid on the surface of the roadway. The metal mesh and W-steel strip are tightly pressed against the surface of the surrounding rock by the anchor at the end of the grouting anchor cable (1) and the nut at the end of the grouting anchor rod (2). The grouting reinforcement ring of the grouting anchor cable (1) and the anchor cable skeleton together form a composite beam structure. The grouting anchor rod (2) inhibits the bulging of the side wall and the expansion of the plastic zone by the overall reinforcement of the side wall surrounding rock.

Images