Roadway tunneling method

Abstract

The invention discloses a roadway tunneling method, and relates to the technical field of roadways. The roadway tunneling method comprises the steps that a slotting hole set, a compensation hole set, a hole expanding hole set and a peripheral hole set are sequentially arranged, and the slotting hole set, the compensation hole set, the hole expanding hole set and the peripheral hole set are symmetrically arranged around the center of the section of a roadway; hole cavities in the slotting hole set, the compensation hole set, the hole expanding hole set and the peripheral hole set are all perpendicular to the section of the roadway and extend in the long axis direction of the roadway. The compensation holes are empty holes, the slotting holes, the slot expanding holes and the peripheral holes are charge holes, charge bags are loaded into each charge hole in a layered manner, each charge hole is subjected to delayed blasting layer by layer in the long axis direction of the roadway until the roadway is formed, the slotting hole group, the slot expanding hole group and the peripheral hole group are detonated in sequence, and the slots are gradually detonated and expanded from the center of the roadway to the boundary. According to the roadway method provided by the invention, layered delayed blasting is carried out on a single charging hole, and the blasting time is delayed in groups of all charging holes, so that a sufficient blasting compensation space is provided for subsequent blasting by previous blasting, and the roadway tunneling efficiency is improved.

Description

Technical Field

[0001] The present application relates to the technical field of tunnel excavation, and in particular to a tunnel excavation method. Background Art

[0002] As a key technology in the construction process of underground engineering, the construction quality and efficiency of tunnel excavation construction technology directly affect the safety and progress of the entire project. Tunnel excavation construction technology can be divided into drilling and blasting method, mechanical excavation method and comprehensive excavation method. Among them, drilling and blasting method is the most widely used tunnel excavation construction technology. It mainly breaks the rock through construction processes such as drilling, charging, and blasting, and performs slag removal and support work to form tunnel space.

[0003] The existing blasting method uses the tunnel section as the free surface. Due to the narrow blasting compensation space, a single blasting cycle is affected by the surrounding rock clamping effect, which greatly restricts the full play of the blasting performance. It is difficult to achieve the optimal utilization of explosive energy under limited space conditions, resulting in a low blasting energy utilization rate, low blasting efficiency, and reduced single-cycle multiplier footage efficiency. Summary of the invention

[0004] In view of this, the present application provides a tunnel excavation method, the purpose of which is to solve one of the technical problems in the prior art.

[0005] To achieve the above objectives, the technical solutions adopted in this application are as follows:

[0006] In a first aspect, an embodiment of the present application provides a tunnel excavation method, comprising:

[0007] Along the direction from the center of the tunnel section to the outside, a slotting hole group, a compensating hole group, a slot expansion hole group and a peripheral hole group are sequentially arranged, and the slotting hole group, the compensating hole group, the slot expansion hole group and the peripheral hole group are symmetrically arranged around the center of the tunnel section;

[0008] Each hole cavity in the cut hole group, the compensating hole group, the expanded slot hole group and the peripheral hole group is perpendicular to the tunnel section and extends along the long axis direction of the tunnel;

[0009] The compensation holes are empty holes, while the slot holes, expansion holes and peripheral holes are all charge holes;

[0010] Each charge hole is loaded with explosive packages in layers, and the explosive packages are detonated layer by layer in each charge hole along the long axis direction of the tunnel until a tunnel is formed. In addition, after the explosion of the previous layer of explosive packages in the same charge hole, a blasting compensation space is provided for the explosion of the next layer of explosive packages.

[0011] The slotting hole group, slot expansion hole group and peripheral hole group are detonated in sequence, and the slot expansion is gradually blasted from the center of the tunnel to the boundary.

[0012] In one embodiment of the first aspect, the slotting hole group, the slot expansion hole group and the peripheral hole group are detonated in a delayed sequence and in staggered layers:

[0013] First, detonate the first layer of explosive charge in the slot hole group;

[0014] Then, the first layer of explosive charge of the slot expansion hole group and the last layer of explosive charge of the slot cutting hole group are detonated simultaneously;

[0015] Then, the latter layer of explosive charge of the expansion slot hole group and the former layer of explosive charge of the peripheral hole group are detonated simultaneously;

[0016] Finally, the last layer of explosive charges in the surrounding hole group are detonated.

[0017] In one of the embodiments of the first aspect, the expanded slot hole group includes multiple layers of expanded slot hole groups, and the multiple expanded slot holes in each layer of expanded slot hole group are symmetrically arranged around the center position of the tunnel section. Along the direction from the center of the tunnel section to the outside, the hole spacing between adjacent expanded slot holes in each layer of expanded slot hole group gradually increases, and the spacing between adjacent expanded slot hole groups gradually increases.

[0018] In one embodiment of the first aspect, during the blasting process of the slot expansion hole group, the slot expansion hole groups are detonated in sequence and in layers from the center of the tunnel section outward:

[0019] First, the first layer of explosive packs in the inner expanded slot hole grouping is detonated, and then the second layer of explosive packs in the outer inner expanded slot hole grouping and the first layer of explosive packs in the outer expanded slot hole grouping are detonated simultaneously.

[0020] In one of the embodiments of the first aspect, during the blasting process of the single-layer expanded slot hole grouping, the expanded slot holes arranged on the horizontal center line and the vertical center line of the tunnel section are detonated first, and then the remaining expanded slot holes are detonated.

[0021] In one embodiment of the first aspect, the peripheral hole group is arranged along the contour line of the tunnel section, and the peripheral hole group includes:

[0022] A plurality of bottom plate holes, wherein the plurality of bottom plate holes are arranged at intervals along the bottom contour line of the tunnel section and are arranged symmetrically at the center position of the tunnel section;

[0023] A plurality of edge holes are arranged along the remaining contour line of the tunnel section and are symmetrically arranged at the center position of the tunnel section.

[0024] In one embodiment of the first aspect, the edge holes are detonated first and then the bottom holes.

[0025] In one of the embodiments of the first aspect, the slot hole group, the compensation hole group and the peripheral hole group all adopt a hole-by-hole layered charging sequence. When charging a single hole, the charging is performed backwards from the inside to the outside of the hole cavity, and an uncoupled layered continuous charging structure is adopted.

[0026] In one embodiment of the first aspect, when charging a single hole, the explosive roll and the digital electronic detonator are installed at the bottom of the hole, and then the explosive is filled, and the filling is performed using taphole mud or an alternative filling material, so as to complete the single-layer charging;

[0027] Repeat the single-layer charging process for multiple times on a single charging hole until the opening of the charging hole is sealed.

[0028] In one embodiment of the first aspect, in the same charging hole, layered blasting is performed along the hole mouth toward the hole bottom according to a preset delayed blasting time.

[0029] Compared with the prior art, the beneficial effects of the present application are as follows: the present application proposes a tunnel method, comprising sequentially arranging a groove hole group, a compensation hole group, an expansion groove hole group and a peripheral hole group in a direction from the center of the tunnel section to the outside, wherein the groove hole group, the compensation hole group, the expansion groove hole group and the peripheral hole group are symmetrically arranged around the center of the tunnel section;

[0030] Each hole cavity in the slot hole group, compensation hole group, slot expansion hole group and peripheral hole group is perpendicular to the cross section of the tunnel and extends along the long axis of the tunnel; the compensation hole is an empty hole, and the slot hole, slot expansion hole and peripheral hole are all charged holes; each charge hole is loaded with explosive bags in layers, and each charge hole is delayed blasted layer by layer in the long axis direction of the tunnel until the tunnel is formed, so that the blasting of the previous layer of explosive bags in the same charge hole provides blasting compensation space for the blasting of the next layer of explosive bags; the slot hole group, slot expansion hole group and peripheral hole group are detonated in sequence, and the slot expansion is gradually blasted from the center of the tunnel to the boundary. After the initial blasting space is formed with the slot hole as the center, blasting is carried out in sequence from the inside to the outside, and the blasting compensation space is gradually expanded to ensure that the previous detonation can provide sufficient compensation space requirements for the subsequent adjacent detonation process, thereby improving the blasting efficiency. BRIEF DESCRIPTION OF THE DRAWINGS

[0031] In order to more clearly illustrate the technical solutions of the embodiments of the present application, the drawings required for use in the embodiments will be briefly introduced below. It should be understood that the following drawings only show certain embodiments of the present application and therefore should not be regarded as limiting the scope. For ordinary technicians in this field, other related drawings can be obtained based on these drawings without paying creative work.

[0032] Figure 1 The diagram shows the layout of blasthole positions in a tunnel section in some embodiments of the present application;

[0033] Figure 2 It shows a time sequence diagram of delayed detonation of blastholes in the surface blasting layer in some embodiments of the present application;

[0034] Figure 3 It shows a time sequence diagram of delayed detonation of blastholes of the inner blasting layer in some embodiments of the present application;

[0035] Figure 4 The charging structure diagram of a single blast hole in some embodiments of the present application is shown;

[0036] Figure 5 Shows Figure 1 The explosion structure diagram of the section at AA in the middle when the delay is 0ms;

[0037] Figure 6 Shows Figure 1 The explosion structure diagram of the section at AA in the middle with a delay of 10ms;

[0038] Figure 7 Shows Figure 1 The blasting structure diagram of the section at AA in the middle with a delay of 250ms;

[0039] Figure 8 Shows Figure 1 The blasting structure diagram of the section at AA in the middle with a delay of 500ms;

[0040] Fig. 9 Shows Figure 1 The blasting structure diagram of the section at AA in the middle with a delay of 750ms;

[0041] Fig.10 Shows Figure 1 The blasting structure diagram of the section at AA in the middle with a delay of 1100ms;

[0042] Fig.11 Shows Figure 1 The blasting structure diagram of the section at AA in the middle with a delay of 1600ms.

[0043] Explanation of main component symbols: 1-surrounding rock; 2-tunnel section; 301-compensation hole; 302-charging hole; 3021-groove hole; 3022-first circle expansion hole grouping; 3023-second circle expansion hole grouping; 3024-third circle expansion hole grouping; 3025-peripheral hole group; 3026-edge hole; 3027-bottom plate hole; 4-charging structure; 401-first layer of rock emulsion explosive; 402-second layer of rock emulsion explosive; 403-digital electronic detonator; 404-gun mud; 405-foot line; 5-blasting compensation space; 501-initial blasting compensation space. DETAILED DESCRIPTION

[0044] The embodiments of the present application are described in detail below, and examples of the embodiments are shown in the accompanying drawings, wherein the same or similar reference numerals throughout represent the same or similar elements or elements having the same or similar functions. The embodiments described below with reference to the accompanying drawings are exemplary and are only used to explain the present application, and cannot be understood as limiting the present application.

[0045] In the description of the present application, it should be understood that the terms "center", "longitudinal", "lateral", "length", "width", "thickness", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside", "clockwise", "counterclockwise", "axial", "radial", "circumferential" and the like indicate orientations or positional relationships based on the orientations or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the present application and simplifying the description, and do not indicate or imply that the referred device or element must have a specific orientation, be constructed and operated in a specific orientation, and therefore should not be understood as a limitation on the present application.

[0046] In addition, the terms "first" and "second" are used for descriptive purposes only and should not be understood as indicating or implying relative importance or implicitly indicating the number of the indicated technical features. Thus, a feature defined as "first" or "second" may explicitly or implicitly include one or more of the features. In the description of this application, the meaning of "plurality" is two or more, unless otherwise clearly and specifically defined.

[0047] In this application, unless otherwise clearly specified and limited, the terms "installed", "connected", "connected", "fixed" and the like should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection or an indirect connection through an intermediate medium, it can be the internal connection of two elements or the interaction relationship between two elements. For ordinary technicians in this field, the specific meanings of the above terms in this application can be understood according to specific circumstances.

[0048] In the present application, unless otherwise clearly specified and limited, a first feature being “above” or “below” a second feature may mean that the first and second features are in direct contact, or the first and second features are in indirect contact through an intermediate medium. Moreover, a first feature being “above”, “above”, and “above” a second feature may mean that the first feature is directly above or obliquely above the second feature, or simply means that the first feature is higher in level than the second feature. A first feature being “below”, “below”, and “below” a second feature may mean that the first feature is directly below or obliquely below the second feature, or simply means that the first feature is lower in level than the second feature.

[0049] like Figure 1 As shown, an embodiment of the present application provides a tunnel excavation method comprising:

[0050] Step S10, along the direction from the center of the tunnel section 2 to the outside, set the groove hole group, compensation hole group, expansion hole group and peripheral hole group 3025 in sequence, and the groove hole group, compensation hole group, expansion hole group and peripheral hole group 3025 are symmetrically arranged around the center of the tunnel section 2.

[0051] Among them, a tunnel is formed in the surrounding rock 1, and the tunnel section 2 refers to the excavation and support of rocks or soil during underground mining or tunnel construction, and finally forms a tunnel cross section that meets the design requirements.

[0052] In the present application, the tunnel section 2 is also the working surface for drilling construction and provides an initial free surface for tunnel blasting, thereby reducing the energy required for blasting and improving the blasting effect.

[0053] like Figure 2 and Figure 3 As shown, a plurality of charging holes 302 are arranged in the compensation hole group, the expansion slot hole group and the peripheral hole group 3025, and the groove hole group, the compensation hole group, the expansion slot hole group and the peripheral hole group 3025 form a concentric ring structure with multiple ring layers as a whole.

[0054] It should be noted that the structure of the concentric rings is circular, rectangular, polygonal or has the same shape as the contour of the tunnel section 2 .

[0055] Step S20, each hole cavity in the groove hole group, the compensation hole group, the expansion hole group and the peripheral hole group 3025 is perpendicular to the tunnel section 2 and extends along the long axis direction of the tunnel.

[0056] like Figure 1 As shown, a drilling rig is used to construct a vertical tunnel section 2 to form a slot hole group, a compensation hole group, an expansion hole group and a peripheral hole group 3025 that extend horizontally and have the bottom of the hole located in the same vertical section, thereby avoiding drilling deviation and perforation.

[0057] In some embodiments, the blast holes in the cut hole group, the compensation hole group, the expansion hole group and the peripheral hole group 3025 are all medium-depth holes or deep holes. Generally, the drilling depth of the medium-depth hole is 5 meters to 20 meters, and the drilling depth of the deep hole is more than 20 meters.

[0058] In step S30 , the compensation hole 301 is an empty hole, and the groove hole 3021 , the expanded groove hole and the peripheral holes are all charging holes 302 .

[0059] By setting up empty holes, the number of charging holes 302 is reduced, and the cost is reduced. By setting up a compensation hole group on the periphery of the slot hole group, the empty space of the compensation hole 301 compensates for the blasting effect of the slot hole group to form sufficient blasting compensation space 5.

[0060] Step S40, explosive packages are loaded in layers in each charging hole 302, and each charging hole 302 is blasted layer by layer along the long axis direction of the tunnel until a tunnel is formed, so that after the previous layer of explosive packages in the same charging hole 302 are blasted, a blasting compensation space 5 is provided for the blasting of the next layer of explosive packages.

[0061] In one embodiment, if Figure 1As shown, two layers of drug packages are arranged in each drug charging hole 302, and the depth of each layer is 2.5m to 4m. In other embodiments, the number of drug package layers and the depth value of each layer can be adjusted according to the actual cutting groove depth.

[0062] Each charge hole 302 is blasted layer by layer in the direction of the long axis of the tunnel, which means that each charge hole 302 is blasted layer by layer in the direction of the tunnel section 2 going deeper into the tunnel.

[0063] Step S50, sequentially detonating the trenching hole group, the slot expansion hole group and the peripheral hole group 3025, gradually blasting and expanding the trench from the center of the tunnel to the boundary.

[0064] After the initial blasting space is formed with the slot hole 3021 as the center, group blasting is carried out from the inside to the outside in sequence, and the blasting compensation space 5 is gradually expanded to ensure that the previous detonation can provide sufficient compensation space requirements for the subsequent adjacent detonation process, thereby improving the blasting efficiency.

[0065] In some embodiments, the slotting hole group, the expanding slotting hole group and the peripheral hole group 3025 are detonated in sequence with delayed detonation:

[0066] First, introduce the first layer of explosive package of the slot hole group;

[0067] Then, the first layer of explosive charge of the slot expansion hole group and the last layer of explosive charge of the slot cutting hole group are detonated simultaneously;

[0068] Then, the latter layer of explosive charge of the expansion slot hole group and the former layer of explosive charge of the peripheral hole group are detonated simultaneously;

[0069] Finally, the last layer of explosive charges in the surrounding hole group are detonated until the tunnel is formed.

[0070] In this way, the blasting is carried out in sequence, synchronously and staggered, thereby improving the blasting efficiency. Sequentially means that the slotting hole group, the slot expansion hole group and the peripheral hole group 3025 are blasted in sequence; synchronously means that the detonation time is the same; staggered means that the positions with the same detonation time are in different hole groups, and the detonated explosive bags are located in different layers.

[0071] like Figure 5 and Figure 6 As shown, the free surface of the blasting of the first layer of the charge of the slot hole 3021 is the tunnel section 2, and the free surface of the blasting of the first layer of the charge of the slot expansion hole group and the last layer of the charge of the slot hole 3021 is the tunnel section 2 and the blasting compensation space 5 formed by the first layer of the blasting of the slot hole 3021, and the blasting compensation space 5 at this time is in a step shape. Similarly, the free surface of the blasting of the last layer of the charge of the slot expansion hole and the first layer of the charge of the peripheral hole is the blasting compensation space 5 formed by the first layer of the slot expansion hole group and the last layer of the slot hole 3021, which further expands the volume of the step-shaped blasting compensation space 5 and improves the blasting efficiency.

[0072] like Figures 6 to 11 In subsequent multiple blastings, the volume of the stepped temporary blasting compensation space 5 gradually increases, and the blasting efficiency gradually improves.

[0073] In addition, with the layer-by-layer delayed blasting of the same charge hole 302, the energy from the explosion of the next layer of explosive packs can act on the broken bulk formed by the blasting of the previous layer, causing a secondary impact on the broken bulk, thereby increasing the single-hole blasting throwing distance and blasting energy utilization rate, reducing the size of the blasting bulk and the energy consumption of explosives, increasing the single-cycle excavation footage to the greatest extent, reducing the number of cycle operations and repeated preparation time, improving the construction efficiency and speed of tunnel excavation, and reducing excavation costs.

[0074] In some embodiments, Figure 1 As shown, the number of the middle slot hole 3021 in the slot hole group is one, and the center axis position of the slot hole 3021 coincides with the center axis position of the tunnel section 2. In other embodiments, the number and hole spacing of the slot holes 3021 can be adjusted as required.

[0075] In some embodiments, Figure 1 and Figure 2 As shown, the multiple compensation holes 301 in the compensation hole group are arranged in a rectangular shape, and the hole distances between the compensation holes 301 are the same.

[0076] The diameter of the compensation hole 301 is larger than that of the charge hole 302 .

[0077] The hole distance between the compensation hole 301 and the slot hole 3021 is D1, and the diameter of the compensation hole 301 is D2, which satisfies: 1.5<D2 / D1<2. D2 / D1 is 1.6, 1.7, 1.8, 1.9, etc., which are not limited to the values ​​of the examples. In this way, after the slot hole 3021 explodes, the compensation hole group can better cooperate with the compensation hole group demarcation area of ​​the surface blasting layer, further compensate for the blasting effect of the slot hole group, and form a sufficient blasting compensation space 5.

[0078] like Figure 1 As shown, a plurality of compensation holes 301 are evenly distributed in a rectangular shape around the center of the lane.

[0079] In some embodiments, the expanded slot hole grouping includes a multi-layer expanded slot hole grouping.

[0080] In one embodiment, the shape of each expansion slot hole group is the same as the shape of the compensation hole group, so that the explosion effect is more uniform.

[0081] In one embodiment, the multiple expanded slot holes in each layer of expanded slot hole grouping are symmetrically arranged around the center position of the tunnel section 2, and the spacing between adjacent expanded slot hole groups gradually increases from the center of the tunnel section 2 to the outside.

[0082] like Figure 2As shown, the spacing between the first circle expansion slot hole group 3022 and the compensation hole 301 is D3, which satisfies: 0.8<D3 / D1<1. D3 / D1 is 0.83, 0.85, 0.87, 0.89, etc., which are not limited to the exemplified values.

[0083] The spacing between the second circle expanded slot hole group 3023 and the first circle expanded slot hole group 3022 is D4, which satisfies: 0.5<D4 / D3<1. D4 / D3 is 0.6, 0.7, 0.8, 0.9, etc., which is not limited to the exemplified values.

[0084] The spacing between the third circle expanded slot hole group 3024 and the second circle expanded slot hole group 3023 is D5, which satisfies: 2<D5 / D4<3. D5 / D4 is 2.1, 2.3, 2.5, 2.7, 2.9, etc., which are not limited to the examples. Since the temporary blasting compensation space 5 mentioned above gradually increases, the blasting efficiency of each time gradually increases, and the blasting cost can be reduced by reducing the blasthole density of the expanded slot hole group.

[0085] In some embodiments, during the blasting process of the slot expansion hole group, the slot expansion hole groups are detonated in sequence and in layers from the center of the tunnel section 2 outward:

[0086] First, the first layer of explosive packs in the inner layer expanded slot hole grouping is detonated, and then the second layer of explosive packs in the outer layer expanded slot hole grouping and the first layer of explosive packs in the outer layer expanded slot hole grouping are detonated simultaneously. In this way, the inner layer expanded slot hole grouping blasting reserves sufficient time and blasting compensation space 5 for the outer layer expanded slot hole grouping blasting, thereby improving the blasting efficiency.

[0087] In some embodiments, during the blasting process of the single-layer expansion slot hole grouping, the expansion slot holes arranged on the horizontal center line and the vertical center line of the tunnel section 2 are detonated first, and then the remaining expansion slot holes are detonated.

[0088] like Figure 2 As shown, in the first group of slot holes 3021, the delay detonation of the expanded slot holes set on the horizontal center line and the vertical center line of the tunnel section 2 is 450ms, and the delay detonation of the remaining expanded slot holes is 500ms. In this way, the slot holes 3021 located in the middle position of the first group of slot holes 3021 are detonated first, expanding the temporary blasting compensation space 5 for the subsequent slot holes 3021 located at other positions of the first group of slot holes 3021, thereby improving the blasting efficiency.

[0089] In some embodiments, the peripheral hole group 3025 is arranged along the contour line of the tunnel section 2, and the peripheral hole group 3025 is used for blasting to form a tunnel boundary shape that meets the design size requirements.

[0090] The peripheral hole group 3025 includes a plurality of bottom plate holes 3027 and a plurality of edge holes 3026 .

[0091] like Figure 2and Figure 3 As shown, a plurality of bottom plate holes 3027 are arranged at intervals along the bottom contour line of the tunnel section 2, and are symmetrically arranged at the center position of the tunnel section 2; a plurality of edge holes 3026 are arranged along the remaining contour line of the tunnel section 2, and are symmetrically arranged at the center position of the tunnel section 2, so that the blasting boundary is more in line with the designed shape.

[0092] In some embodiments, during the blasting process of a single blasting layer, the edge holes 3026 are detonated first, and then the bottom plate holes 3027 are detonated.

[0093] like Figure 2 and Figure 3 As shown, the top and the edge holes 3026 on both sides are blasted first, which can loosen and release local stress in advance, avoid accidental collapse of the roof after the blasting of the bottom plate holes 3027, and reduce the risk of roof collapse after the tunnel is formed.

[0094] At the same time, the crushed rocks produced after the blasting of the top edge hole 3026 have initial kinetic energy to be thrown outwards, and the bottom plate hole 3027 is subsequently detonated, and the detonation gas produced will push the crushed rocks to the free surface, forming a coherent throwing trajectory, thereby preventing the rock from rebounding and impacting the formed tunnel wall.

[0095] The bottom area of ​​the tunnel is used for gravel transportation and needs to be relatively flat. The post-detonation strategy allows the bottom plate blasting to fully utilize the gravity squeezing effect of the top broken rock mass to reduce the "under-excavation" or "over-excavation" phenomenon.

[0096] In some embodiments, the slot hole group, the compensation hole group and the peripheral hole group 3025 all adopt a hole-by-hole layered charging sequence. When charging a single hole, the charging is performed backwards from the inside to the outside of the hole cavity, and an uncoupled layered continuous charging structure 4 is adopted.

[0097] The uncoupled layered continuous charging structure 4 is an optimized blasting charging technology, which is widely used in medium-depth and deep-hole blasting projects. This charging structure 4 can significantly improve the blasting effect, reduce energy loss, and effectively control the impact of blasting on the surrounding environment by reasonably designing the gap between the explosive and the blasthole wall (i.e., the uncoupled coefficient) and the layered charging method.

[0098] In some embodiments, when charging a single hole, the explosive roll and the digital electronic detonator 403 are installed at the bottom of the hole, and then the explosive is filled, and the taphole mud 404 or an alternative filling material is used for filling, so as to complete the single-layer charging;

[0099] The single-layer charging process is repeated multiple times for a single charging hole 302 until the opening of the charging hole 302 is blocked.

[0100] The total length of the single-layer charge structure 4 is L1, which satisfies: 2.5 meters ≤ L1 ≤ 4 meters.

[0101] The length of the explosive in the single-layer charge structure 4 is L2, which satisfies: 1 meter ≤ L2 ≤ 3.5 meters.

[0102] The length of the taphole mud 404 or the alternative filler of the single-layer charge structure 4 is L3, which satisfies: 0.3 m ≤ L3 ≤ 0.7 m.

[0103] In some embodiments, in the same charging hole 302, layered blasting is performed along the hole mouth toward the hole bottom according to a preset delayed blasting time, so as to realize a blasting method from the outside to the inside.

[0104] The following is a specific example for explanation:

[0105] like Figure 2 and Figure 3 As shown, there are 8 compensation holes 301 and 53 charging holes 302 in the blast hole.

[0106] In this embodiment, the design size of the tunnel section 2 is 3600mm*3200mm, and the depth of each blast hole is 6000mm.

[0107] The number of the cutout hole 3021 is one, and the compensation hole 301 surrounds the cutout hole 3021 at the center of the tunnel section 2 and is evenly distributed. The blasthole diameter of the compensation hole 301 is 90 mm, the blasthole spacing is 170 mm, and the overall arrangement is quadrilateral, preferably square.

[0108] In this embodiment, all the charging holes 302 are arranged in four circles from the inside to the outside, with the groove hole 3021 at the center of the tunnel section 2 as the center, and are arranged in a ring shape as a whole.

[0109] The diameter of each charge hole 302 is 45 mm. The spacing between the holes in the first circle of expansion slot hole group 3022 is 320 mm, and the overall arrangement is a quadrilateral, preferably a square arrangement, with a side length of 640 mm.

[0110] The spacing between the blast holes in the second circle expanded slot hole group 3023 is 620 mm, and the overall arrangement is a quadrilateral, preferably a square arrangement, with a side length of 1240 mm. The spacing between the blast holes in the first circle expanded slot hole group 3022 and the second circle expanded slot hole group 3023 is 300 mm.

[0111] The spacing between the blast holes in the third circle expanded slot hole group 3024 is 560 mm, and the overall arrangement is a quadrilateral, preferably a square arrangement, with a side length of 2240 mm. The spacing between the blast holes in the second circle expanded slot hole group 3023 and the third circle expanded slot hole group 3024 is 500 mm.

[0112] The blast holes in the peripheral hole group 3025 are evenly arranged along the boundary contour line of the tunnel section 2, and the blast hole spacing is 600 mm. The blast hole spacing between the third circle expansion slot hole group 3024 and the edge hole 3026 is 680 mm, and the blast hole spacing between the third circle expansion slot hole group 3024 and the bottom plate hole 3027 is 380 mm.

[0113] See also Figure 4 , provides a preferred structure of the charge structure 4 in this embodiment. The charge structure 4 adopts a layered uncoupled charge form, and is composed of a first layer of rock emulsion explosive 401, a second layer of rock emulsion explosive 402, a digital electronic detonator 403, taphole mud 404, and a foot line 405.

[0114] Among them, the lengths of the first layer of rock emulsion explosive 401 and the second layer of rock emulsion explosive 402 are both 2500 mm, and the design length of the single-stage taphole mud 404 is 500 mm.

[0115] In this embodiment, the first layer of rock emulsion explosive 401 and the second layer of rock emulsion explosive 402 are both No. 2 rock emulsion explosives, and each explosive roll has a diameter of 30 mm, a length of 300 mm, and a mass of 300 g.

[0116] See also Figures 5 to 11 , provides the preferred structure for designing the detonation sequence and the delayed detonation time in this embodiment. Figure 5 As shown, the charge hole 302 as a whole adopts a design detonation sequence of layers within the hole and circles within the layers.

[0117] Among them, combined with reference Figure 2 and Figure 3 The single charge hole 302 is detonated in layers, and the designed time delay detonation time interval between the first layer of rock emulsion explosive 401 and the second layer of rock emulsion explosive 402 is 500ms.

[0118] like Figure 2 or Figure 3 As shown, during the blasting process of a single blasting layer, detonations are performed circle by circle from the center to the outside. In the first circle of expanded slot hole grouping 3022 to the third circle of expanded slot hole grouping 3024, the designed delayed detonation time interval between adjacent blast holes is 50ms, and the designed delayed detonation time interval between the edge holes 3026 and the bottom plate holes 3027 in the peripheral hole group 3025 is 100ms.

[0119] Combined with reference Figure 2 and Figure 3The initial detonation delay times of the first circle expanded slot hole group 3022, the second circle expanded slot hole group 3023, the third circle expanded slot hole group 3024, and the peripheral hole group 3025 of the surface rock emulsion explosive are 200ms, 450ms, 700ms, and 1000ms, respectively. The initial detonation delay times of the first circle expanded slot hole group 3022, the second circle expanded slot hole group 3023, the third circle expanded slot hole group 3024, and the peripheral hole group 3025 of the inner layer rock emulsion explosive are 700ms, 950ms, 1200ms, and 1500ms, respectively.

[0120] Need to explain, Figure 2 and Figure 3 In order to more intuitively display the blasting methods of the front and rear layers, each charging hole is numbered, such as Figure 2 In the example, "9-1" means that the number of the slot hole is 9, and 1 refers to the previous layer. In the previous layer, the number of the charge holes is 9 to 61. "ms10" means that the delay blasting time is 10ms. For example, in Figure 3 In the figure, "9-2" means that the serial number of the slot hole is 9, and 2 refers to the next layer. In the next layer, the serial numbers of the charge holes are also 9 to 61. "ms500" means that the delayed blasting time is 500ms.

[0121] Please refer to Figure 2 and Figure 3 The delayed blasting time of the slotting hole 3021, the slot expansion hole group and the surrounding hole group 3025 in sequence and staggered layers is as follows:

[0122] First, the explosive pack in the layer before the slot hole 3021 is detonated, and the delay time is 10ms;

[0123] Then, the first layered explosive charge of the first circle expansion slot group 3022 is detonated, with delay times of 200ms and 250ms respectively;

[0124] Then, the first layer of explosive charge of the second circle of expanded slot hole group 3023 is detonated, with delay times of 450ms and 500ms respectively, and when the delay time is 500ms, the last layer of explosive charge of the cut slot hole 3021 is detonated simultaneously;

[0125] Then, the first layer of the explosive package of the third circle expanded slot hole group 3024 is detonated, and the delay time is 700ms, 750ms, and 800ms respectively. When the delay time is 700ms and 750ms, the last layer of the explosive package of the first circle expanded slot hole group 3022 is detonated simultaneously;

[0126] Then, the first layer of the edge hole 3026 is detonated, and the delay time is 1000ms. When the delay time is 950ms and 1000ms, the last layer of the second circle expansion slot hole group 3023 is detonated at the same time.

[0127] Then detonate the previous layered charge in the bottom plate hole 3027, with a delay time of 1100ms;

[0128] Then, the next layered charge in the third circle of expanded slots is detonated, with delay times of 1200ms, 1250ms, and 1300ms respectively;

[0129] Then, the next layered charge in the edge hole 3026 is detonated, and the delay time is 1500ms;

[0130] The next layer of explosive charge in the bottom plate hole 3027 is detonated again, with a delay time of 1600ms.

[0131] To sum up, the tunnel excavation method provided in the present application can give full play to the full-space blasting compensation space 5 and the free surface, greatly improve the blasting energy utilization rate and the single-cycle footage effect, fundamentally reduce the number of cycle operations and repeated preparation time, reduce personnel operation risks, and improve tunnel efficiency. It has the characteristics of simple structure, safety and efficiency, and good blasting effect.

[0132] In the description of this specification, the description with reference to the terms "one embodiment", "some embodiments", "example", "specific example", or "some examples" etc. means that the specific features, structures, materials or characteristics described in conjunction with the embodiment or example are included in at least one embodiment or example of the present application. In this specification, the schematic representations of the above terms do not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials or characteristics described may be combined in any one or more embodiments or examples in a suitable manner. In addition, those skilled in the art may combine and combine the different embodiments or examples described in this specification and the features of the different embodiments or examples, without contradiction.

[0133] Although the embodiments of the present application have been shown and described above, it can be understood that the above embodiments are exemplary and cannot be understood as limitations on the present application. Ordinary technicians in this field can change, modify, replace and modify the above embodiments within the scope of the present application.

Claims

1. A tunnel excavation method, characterized in that: include: Along the direction from the center of the tunnel section to the outside, a slotting hole group, a compensating hole group, a slot expansion hole group and a peripheral hole group are sequentially arranged, and the slotting hole group, the compensating hole group, the slot expansion hole group and the peripheral hole group are symmetrically arranged around the center of the tunnel section; Each hole cavity in the cut hole group, the compensating hole group, the expanded slot hole group and the peripheral hole group is perpendicular to the tunnel section and extends along the long axis direction of the tunnel; The compensation holes are empty holes, while the slot holes, expansion holes and peripheral holes are all charge holes; Each charging hole is loaded with explosive packages in layers, and each charging hole is blasted layer by layer along the long axis direction of the tunnel until a tunnel is formed, so that the blasting of the previous layer of explosive packages in the same charging hole provides blasting compensation space for the blasting of the next layer of explosive packages; The slotting hole group, slot expansion hole group and peripheral hole group are detonated in sequence, and the slot expansion is gradually blasted from the center of the tunnel to the boundary.

2. The tunnel excavation method according to claim 1, characterized in that: The slotting hole group, slot expansion hole group and peripheral hole group are detonated in sequence and in different layers with a delay: First, detonate the first layer of explosive charge in the slot hole group; Then, the first layer of explosive charge of the slot expansion hole group and the last layer of explosive charge of the slot cutting hole group are detonated simultaneously; Then, the latter layer of explosive charge of the expansion slot hole group and the former layer of explosive charge of the peripheral hole group are detonated simultaneously; Finally, the last layer of explosive charges in the surrounding hole group are detonated.

3. The tunnel excavation method according to claim 2, characterized in that: The expanded slot hole group includes multiple layers of expanded slot hole groups. The multiple expanded slot holes in each layer of expanded slot hole group are symmetrically arranged around the center position of the tunnel section. The spacing between adjacent expanded slot hole groups gradually increases from the center of the tunnel section to the outside.

4. The tunnel excavation method according to claim 3, characterized in that: During the blasting process of the slot expansion hole group, the slot expansion hole groups are detonated in sequence and in layers from the center of the tunnel section to the outside: First, the first layer of explosive packs in the inner expanded slot hole grouping is detonated, and then the second layer of explosive packs in the outer inner expanded slot hole grouping and the first layer of explosive packs in the outer expanded slot hole grouping are detonated simultaneously.

5. The tunnel excavation method according to claim 3, characterized in that: In the blasting process of single-layer expansion slot holes grouping, the expansion slot holes set on the horizontal center line and vertical center line of the tunnel section are detonated first, and then the remaining expansion slot holes are detonated.

6. The tunnel excavation method according to claim 1, characterized in that: The peripheral hole groups are arranged along the contour line of the tunnel section, and the peripheral hole groups include: A plurality of bottom plate holes, wherein the plurality of bottom plate holes are arranged at intervals along the bottom contour line of the tunnel section and are arranged symmetrically at the center position of the tunnel section; A plurality of edge holes are arranged along the remaining contour line of the tunnel section and are symmetrically arranged at the center position of the tunnel section.

7. The tunnel excavation method according to claim 6, characterized in that: Detonate the edge holes first, then the bottom holes.

8. The tunnel excavation method according to claim 1, characterized in that: The slot hole group, compensation hole group and peripheral hole group all adopt a hole-by-hole layered charging sequence. When charging a single hole, the charging is carried out in reverse order from the inside to the outside of the hole cavity, and an uncoupled layered continuous charging structure is adopted.

9. The tunnel excavation method according to claim 8, characterized in that: When charging a single hole, install the explosive roll and the digital electronic detonator to the bottom of the hole, and then fill it with explosives, using gun mud or alternative filling materials to fill it, so as to complete the single-layer charging; Repeat the single-layer charging process for multiple times on a single charging hole until the opening of the charging hole is sealed.

10. The tunnel excavation method according to claim 9, characterized in that: In the same charging hole, layered blasting is carried out from the hole mouth to the hole bottom according to the preset delayed blasting time.

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