Method for tunnel excavation using a single-track railway tunnel protection support without risk of collapse

Abstract

The application discloses a tunnel excavation method using a single-line railway tunnel protection support without risk discharge, and the safety protection support comprises a rack, sleeves are arranged on the two sides of the rack, the sleeves are connected with one end of supporting rods, iron buckles are arranged on the supporting rods, a protective net is arranged above the supporting rods, the protective net is arranged in an arch shape, the protective net is connected with the supporting rods through iron sheets, hooks are arranged on the iron sheets, steel strands are arranged on the hooks and cross and cover the protective net; the supporting rods are installed before a single cycle footage support operation of the tunnel, ten supporting rods form a group, the protective net is laid between the supporting rods and the iron sheets, the adjusting device of the supporting rods is started to make the supporting rods elongate and make the protective net quickly adhere to the inner wall of the tunnel, the adhered protective net is supported, pre-supporting is conducted through the protective net, and the safety of the tunnel support operation can be effectively improved.

Description

Technical Field

[0001] This invention relates to the field of single-track railway tunnel construction technology, and in particular to a method for tunnel excavation using a single-track railway tunnel protective support system that eliminates the need for hazard removal. Background Technology

[0002] Currently, the main methods for tunneling in mountainous areas are drill-and-blast (DUB) and tunnel boring machine (TBM) methods. DUB accounts for a significant proportion of tunnel excavation, representing more than half of all tunnel projects. When using DUB, post-blast hazard removal is a crucial step in tunnel excavation, and the time required for hazard removal directly impacts construction progress and costs. When blasting is ineffective, issues such as over-excavation / under-excavation and severe damage to the surrounding rock after blasting can occur, creating significant safety hazards during construction.

[0003] During tunnel excavation, after each cycle of excavation, the exposed surrounding rock needs to be supported by a support system to prevent rockfall or collapse that could injure workers and equipment. Improving tunnel single-cycle excavation speed hinges on hazard mitigation. Existing hazard mitigation methods primarily utilize protective devices to protect workers and equipment, aiming to reduce mitigation time. However, in practical applications, when tunnels are excavated rapidly, protective devices need to be deployed quickly. Some existing protective devices are difficult to disassemble quickly after pre-support is completed, and their position cannot be rapidly adjusted according to the direction of excavation, resulting in poor portability. Summary of the Invention

[0004] The main objective of this invention is to provide a method for tunnel excavation using a single-track railway tunnel protective support system that eliminates the need for hazard removal, thereby addressing existing technical problems.

[0005] To achieve the above objectives, the present invention provides a method for tunnel excavation using a single-track railway tunnel protective support without the need for hazard removal. The protective support includes a platform with sleeves on both sides. The sleeves are connected to one end of a support rod. The support rod has iron buckles and a protective net above it. The protective net is arranged in an arch shape and is connected to the support rod by iron sheets. The iron sheets have hooks, and steel strands are threaded through the hooks. The steel strands cross and cover the protective net.

[0006] The support rod is provided with an adjustment groove, and the adjustment groove is provided with a telescopic rod. The end of the telescopic rod extends out of the support rod and is connected to the iron plate, and can slide and adjust its position within the adjustment groove. There are four iron plates.

[0007] The tunnel excavation method includes the following steps;

[0008] Step 1: Based on the footage advanced in a single cycle, perform drilling and charging operations, calculate and record the sum of the depths of each surrounding hole during the drilling operation. After blasting and muck removal operations, calculate and record the sum of the depths of each borehole along the outline. And calculate the residual borehole rate. ;

[0009] Step 2: Based on the numerical calculation results, conduct an evaluation and classification, and arrange flexible steel wire mesh of different strengths on the tunnel arch and sidewalls respectively;

[0010] Step 3: Use a support system consisting of "support rods + longitudinal connecting rods + right-angle connecting sleeves" to support and fix the flexible wire mesh;

[0011] In step one, the residual borehole rate must be calculated for the corresponding working face during each cycle of advance. ;

[0012] Workers perform drilling and explosive loading operations, while simultaneously calculating and recording the sum of the depths of each surrounding hole during the drilling process. After blasting and muck removal operations, calculate and record the sum of the depths of each borehole along the outline. And calculate the residual borehole rate. ;

[0013] Residual borehole rate The function expression is: ;

[0014] Step two includes,

[0015] Based on the residual borehole rate calculated in step one, if the residual borehole rate is greater than 90%, support operations will be carried out without hazard removal or protection.

[0016] When the residual borehole rate is between 70% and 90%, a flexible steel wire mesh of moderate strength is used to cover the wall surface.

[0017] When the residual borehole rate is less than 70%, high-strength flexible steel wire mesh is used for protection.

[0018] Furthermore, in step three, the support system used for the flexible wire mesh is simple and detachable;

[0019] After the blasting and muck removal are completed, the trolley is pushed to a distance of one cycle advance in front of the working face, and protective rods and flexible wire mesh are installed.

[0020] The trolley is pushed in front of the working face to carry out support work;

[0021] During support operations, the protective netting uses flexible steel wire mesh, and the longitudinal connecting rods directly support it from behind, making it fit the wall surface. If the calculated residual blast hole rate is greater than 90%, the steel frame is removed later; otherwise, the steel frame is retained and the protective netting is used for joint support, so that the protective netting and shotcrete work together to provide support, and only the support system members are removed.

[0022] Without the support of a steel frame, workers, protected by safety netting, proceed directly to the next cycle of drilling and loading operations, while simultaneously recording the number of surrounding holes drilled. .

[0023] The beneficial effects of this invention are reflected in:

[0024] This invention involves installing support rods before a single cycle of tunnel support operations. Ten support rods are grouped together, and a protective net is laid between the support rods and the iron sheet. The adjustment device of the support rods is activated to extend the support rods and quickly fit the protective net against the inner wall of the tunnel. The fitted protective net is then supported, and pre-support is performed through the protective net, which can effectively improve the safety of tunnel support operations.

[0025] This invention takes into account the impact of falling debris from the tunnel arch and sidewalls during the excavation process, which optimizes the excavation technology to a certain extent and shortens the time for a single advance. Attached Figure Description

[0026] Figure 1 This is a schematic diagram of the structure of the present invention;

[0027] Figure 2 This is a schematic diagram of the supporting architecture of the present invention;

[0028] Figure 3 For the present invention Figure 2 Structural side view diagram;

[0029] Figure 4 For the present invention Figure 2 Top view of the structure;

[0030] Figure 5 This is a schematic diagram of the method for tunnel excavation using the safety protection support for single-track railway tunnels that eliminates the need for hazard removal, as described in this invention.

[0031] Explanation of reference numerals in the attached figures:

[0032] 1: Iron sheet; 2: Steel strand; 3: Protective net; 4: Support rod; 5: Sleeve; 6: Iron buckle; 7: Hook; 8: Adjustment groove. Detailed Implementation

[0033] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only a part of the embodiments of the present invention, and not all of them. Unless otherwise specified, the embodiments and features in the embodiments of this application can be combined with each other. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0034] Please see Figure 1-3 This invention provides a single-track railway tunnel protection support without the need for hazard removal, including a platform. The platform has sleeves 5 on both sides, which are connected to one end of a support rod 4. The support rod 4 has iron buckles 6, and a protective net 3 is provided above the support rod 4. The protective net 3 is arranged in an arch shape and is connected to the support rod 4 through an iron sheet 1. The iron sheet 1 has hooks 7, and steel strands 2 are threaded through the hooks 7. The steel strands 2 cross and cover the protective net 3.

[0035] The support rod 4 is provided with an adjustment groove 8, and the adjustment groove 8 is provided with a telescopic rod. The end of the telescopic rod passes through the support rod 4 and is connected to the iron plate 1, and can slide and adjust its position within the adjustment groove 8. There are four iron plates 1.

[0036] Please see Figure 5 The method for tunnel excavation using the aforementioned risk-free single-track railway tunnel protective support includes the following steps:

[0037] Step 1: Based on the footage advanced in a single cycle, perform drilling and charging operations, calculate and record the sum of the depths of each surrounding hole during the drilling operation. After blasting and muck removal operations, calculate and record the sum of the depths of each borehole along the outline. And calculate the residual borehole rate. ;

[0038] Step 2: Based on the numerical calculation results, conduct an evaluation and classification, and arrange flexible steel wire mesh of different strengths on the tunnel arch and sidewalls respectively;

[0039] Step 3: Use a support system consisting of "support rods + longitudinal connecting rods + right-angle connecting sleeves" to support and fix the flexible wire mesh.

[0040] In step one, the residual borehole rate must be calculated for the corresponding working face during each cycle of advance. .

[0041] Workers perform drilling and explosive loading operations, while simultaneously calculating and recording the sum of the depths of each surrounding hole during the drilling process. After blasting and muck removal operations, calculate and record the sum of the depths of each borehole along the outline. And calculate the residual borehole rate. ;

[0042] Residual borehole rate The function expression is: .

[0043] Step two includes,

[0044] Based on the residual borehole rate calculated in step one, if the residual borehole rate is greater than 90%, support operations will be carried out without hazard removal or protection.

[0045] When the residual borehole rate is between 70% and 90%, a flexible steel wire mesh of moderate strength is used to cover the wall surface.

[0046] When the residual borehole rate is less than 70%, high-strength flexible steel wire mesh is used for protection.

[0047] In step three, the support system used for the flexible wire mesh is simple and detachable.

[0048] After the blasting and muck removal are completed, the trolley is pushed to a distance of one cycle advance in front of the working face, and protective rods and flexible wire mesh are installed.

[0049] The trolley is pushed in front of the working face to carry out support work;

[0050] During support operations, the protective netting uses flexible steel wire mesh, and the longitudinal connecting rods directly support it from behind, making it fit the wall surface. If the calculated residual blast hole rate is greater than 90%, the steel frame is removed later; otherwise, the steel frame is retained and the protective netting is used for joint support, so that the protective netting and shotcrete work together to provide support, and only the support system members are removed.

[0051] Without the support of a steel frame, workers, protected by safety netting, proceed directly to the next cycle of drilling and loading operations, while simultaneously recording the number of surrounding holes drilled. .

[0052] It should be noted that if the embodiments of the present invention involve directional indicators such as up, down, left, right, front, back, etc., the directional indicators are only used to explain the relative positional relationship and movement of the components in a specific posture as shown in the attached figure. If the specific posture changes, the directional indicators will also change accordingly.

[0053] Furthermore, if the embodiments of this invention involve descriptions such as "first" or "second," these descriptions are for descriptive purposes only and should not be construed as indicating or implying their relative importance or implicitly specifying the number of technical features indicated. Therefore, a feature defined with "first" or "second" may explicitly or implicitly include at least one of those features. Additionally, the meaning of "and / or" throughout the text includes three parallel solutions; for example, "A and / or B" includes solution A, solution B, or a solution where both A and B are satisfied. Furthermore, "multiple" refers to two or more. Moreover, the technical solutions of the various embodiments can be combined with each other, but this must be based on the ability of those skilled in the art to implement them. When the combination of technical solutions is contradictory or impossible to implement, such a combination of technical solutions should be considered non-existent.

[0054] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the protection scope of the present invention.

Claims

1. A method for tunnel excavation using a single-track railway tunnel protective support system that eliminates the need for hazard removal, characterized in that: The protective support includes a platform, with sleeves (5) on both sides of the platform. The sleeves (5) are connected to one end of a support rod (4). The support rod (4) is provided with iron buckles (6), and a protective net (3) is provided above the support rod (4). The protective net (3) is arranged in an arch shape, and the protective net (3) is connected to the support rod (4) through an iron sheet (1). The iron sheet (1) is provided with hooks (7), and steel strands (2) are threaded through the hooks (7). The steel strands (2) cross and cover the protective net (3). The support rod (4) is provided with an adjustment groove (8), and the adjustment groove (8) is provided with a telescopic rod. The end of the telescopic rod passes through the support rod (4) and is connected to the iron plate (1) and can slide to adjust its position in the adjustment groove (8). There are four iron plates (1). The tunnel excavation method includes the following steps; Step 1: Based on the footage advanced in a single cycle, perform drilling and charging operations, calculate and record the sum of the depths of each surrounding hole during the drilling operation. After blasting and muck removal operations, calculate and record the sum of the depths of each borehole along the outline. And calculate the residual borehole rate. ; Step 2: Based on the numerical calculation results, conduct an evaluation and classification, and arrange flexible steel wire mesh of different strengths on the tunnel arch and sidewalls respectively; Step 3: Use a support system consisting of "support rods + longitudinal connecting rods + right-angle connecting sleeves" to support and fix the flexible wire mesh; In step one, the residual borehole rate must be calculated for the corresponding working face during each cycle of advance. ; Workers perform drilling and loading operations, while simultaneously calculating and recording the sum of the depths of each surrounding hole during the drilling process. After blasting and muck removal operations, calculate and record the sum of the depths of each borehole along the outline. And calculate the residual borehole rate. ; Residual borehole rate The function expression is: ; Step two includes, Based on the residual borehole rate calculated in step one, if the residual borehole rate is greater than 90%, support operations will be carried out without hazard removal or protection. When the residual borehole rate is between 70% and 90%, a flexible steel wire mesh of moderate strength is used to cover the wall surface. When the residual borehole rate is less than 70%, high-strength flexible steel wire mesh is used for protection.

2. The method for tunnel excavation using a single-track railway tunnel protection support system that eliminates the need for hazard removal, as described in claim 1, is characterized in that: In step three, the support system used for the flexible wire mesh is simple and detachable. After the blasting and muck removal are completed, the trolley is pushed to a distance of one cycle advance in front of the working face, and protective rods and flexible wire mesh are installed. The trolley is pushed in front of the working face to carry out support work; During support operations, the protective netting uses flexible steel wire mesh, and the longitudinal connecting rods directly support it from behind, making it fit the wall surface. If the calculated residual blast hole rate is greater than 90%, the steel frame is removed later; otherwise, the steel frame is retained and the protective netting is used for joint support, so that the protective netting and shotcrete work together to provide support, and only the support system members are removed. Without the support of a steel frame, workers, protected by safety netting, proceed directly to the next cycle of drilling and loading operations, while simultaneously recording the number of surrounding holes during the drilling process. .

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