A coal mine rock roadway super-deep hole blasting-mechanical combined tunneling method

Abstract

The application discloses a kind of coal mine rock roadway super-deep hole blasting-mechanical combined driving method, comprising the following steps: step 1, the basic mechanical properties of the rock of the rock roadway to be excavated and the ground stress condition are analyzed;Step 2, the number of super-deep blast holes needed to be drilled on the rock roadway driving section is determined;Step 3, each super-deep blast hole is drilled on the rock roadway driving section using a drilling machine;Step 4, explosives are loaded into each super-deep blast hole and plugged;Step 5, the initiation sequence is determined, and the explosives in each super-deep blast hole are sequentially initiated to blast weaken the rock within the driving path range;Step 6, the driving machine is used for driving.The application first blasts the rock within the driving path range using super-deep blast holes to pre-split, then drives using the driving machine after reducing the integrity of the rock within the driving path range, improves the working efficiency of the driving machine, improves the stability of the surrounding rock, and the blast weakening distance is longer, effectively improving the continuity of the driving.

Description

TECHNICAL FIELD

[0001] The present application belongs to the technical field of coal mine rock roadway driving, and particularly relates to a coal mine rock roadway super-deep hole blasting-mechanical combined driving method. BACKGROUND

[0002] Roadway is the vein of mine production system, and plays an extremely important role in mine production. The driving speed of roadway affects the normal replacement of working face, and is a key factor restricting the efficient production of mine.

[0003] In the past two decades, the coal mining technology and equipment in China have developed rapidly, while the rock roadway construction technology and equipment are not satisfactory. At present, the traditional blasting driving method and the driving machine driving method are generally used for coal mine rock roadway driving in China.

[0004] The main advantages of the blasting driving method are: fast operation preparation, strong adaptability to various rocks, flexible movement, easy to handle technical faults and geological faults, high efficiency and low cost. The disadvantages are: the underground roadway space is small, and if the operation is improper during blasting, it is easy to cause rock splashing, causing harm to personnel and equipment safety; the average driving speed is low; overblasting and underblasting often occur during blasting, the surrounding shaping is poor, and the utilization rate of blast hole is low.

[0005] The driving machine driving can be divided into full-face driving machine driving and fully-mechanized driving machine driving.

[0006] The advantages of full-face driving machine driving are: the driving speed is higher than that of the drilling and blasting method, the longer the driving duration, the better the economic benefit, and when the driving speed is high, the driving operation cost is similar to that of the drilling and blasting method; the stability of the roadway is good. The disadvantages are: the driving operation must be uninterrupted, and only when the driving speed is high and the driving duration is long, the driving is more economical. Most full-face driving machines can only drive circular cross-section roadways, and the lower part needs to be backfilled; branch roadways and curved roads cannot be excavated; the investment in full set of equipment is high, the cost of disassembly, transportation and assembly is also high; it is difficult to pass through faults, and the adaptability to engineering geological conditions is poor.

[0007] The advantages of fully-mechanized driving machine driving are: the driving speed of rock roadway can be improved, the economic benefit is improved, the integrity of rock stratum is not damaged, the designed cross-section can be driven, thereby the support condition can be improved and the maintenance cost can be reduced, and the accident rate is low. The disadvantages are: the cutting teeth are easily worn when hard rock is encountered, and need to be frequently replaced, resulting in the reduction of driving speed and economic benefit. The rock is difficult to break, and the driving efficiency is low; the cutting teeth collide with rock to generate sparks, which has safety hazards. SUMMARY

[0008] The purpose of the present application is to overcome the shortcomings of the prior art, and provide a coal mine rock roadway super-deep hole blasting-mechanical combined driving method.

[0009] To achieve the above object, the present application adopts the following technical solutions:

[0010] A coal mine rock roadway super-deep hole blasting-mechanical combined tunneling method, comprising the following steps:

[0011] Step 1, collect and analyze the engineering, hydrogeological data and rock roadway design data of the tunneling rock roadway, and test and analyze the basic mechanical properties of the rock of the tunneling rock roadway and the ground stress conditions;

[0012] Step 2, determine the number of super-deep blast holes to be drilled on the rock roadway tunneling section;

[0013] Step 3, use a drill to drill each super-deep blast hole in the direction perpendicular to the tunneling section on the rock roadway tunneling section;

[0014] Step 4, load explosives into each super-deep blast hole and plug;

[0015] Step 5, determine the detonation sequence, sequentially detonate the explosives in each super-deep blast hole, and blast the rock in the tunneling path range;

[0016] Step 6, use a tunneling machine to tunnel.

[0017] Preferably, the step 2 comprises the following sub-steps:

[0018] Step 21, determine the diameter D and depth of the super-deep blast hole;

[0019] Step 22, determine the weakening area S1 of a single super-deep blast hole, S1 = 350D 2 ~ 650D 2 ;

[0020] Step 23, calculate the number N of super-deep blast holes to be drilled on the rock roadway tunneling section, N = [S / S1] + 1, S is the section area of the rock roadway tunneling section, [S / S1] represents the maximum integer not exceeding S / S1.

[0021] Preferably, in the step 21, the diameter D of the super-deep blast hole is not greater than 110 mm.

[0022] Preferably, in the step 21, the depth of the super-deep blast hole is not less than 30 m.

[0023] Preferably, the center point of the super-deep blast hole on the rock roadway tunneling section is taken as the center to draw an inscribed circle of the rock roadway tunneling section contour line, and the radius of the inscribed circle is not less than 13D;

[0024] The connecting line of the center points of any two super-deep blast holes on the rock roadway tunneling section is not parallel to the rock roadway bottom edge and the rock roadway side edge straight wall;

[0025] The hole spacing range between any one of the super-deep blast holes on the rock roadway excavation section and the rest of the super-deep blast holes is 15D-35D.

[0026] Preferably, the vertical distance between the center points of any two super-deep blast holes on the rock roadway excavation section along the direction of the straight wall of the rock roadway side is not less than 150mm, and the horizontal distance along the direction of the rock roadway bottom is not less than 150mm.

[0027] Preferably, in the step 4, the blasting decoupling coefficient is not greater than 1.5.

[0028] Preferably, in the step 4, the plugging length of the super-deep blast hole is L, L≥L0, L0 is the larger value of 90D or L1, D is the diameter of the super-deep blast hole, and L1 is one third of the depth of the super-deep blast hole.

[0029] The plugging material of the super-deep blast hole is an expansive rapid-setting cement.

[0030] Preferably, in the step 5, the method for determining the initiation sequence is as follows:

[0031] The rock roadway surrounding rock part needing to be protected is determined, and the distance values of the super-deep blast holes from the rock roadway surrounding rock part needing to be protected are determined, and the order from low to high of the distance values is the initiation sequence of the super-deep blast holes.

[0032] Preferably, in the step 6, the cutting path of the excavator during excavation is perpendicular to the extension direction of the blasting cracks.

[0033] The beneficial effects of the present application are as follows:

[0034] The present application combines the advantages of blasting excavation and excavator excavation, overcomes the respective shortcomings, first pre-fractures the rock in the excavation path range through super-deep blast hole blasting, reduces the integrity of the rock in the excavation path range, then uses the excavator to excavate, the overall investment cost is low, the excavation can be interrupted, the average excavation speed is high; the super-deep hole blasting is used to reduce the integrity of the rock in the excavation path range, avoids the rock splashing, over-blasting and under-excavation in the existing blasting excavation method, at the same time, the rock pre-fracturing effect caused by the super-deep hole blasting improves the rock roadway excavation footage, improves the adaptability of the excavator to the engineering geological conditions, effectively reduces the wear of the cutting teeth of the excavator, the amount of dust and the probability of sparks generated by the collision of the cutting teeth and the rock, improves the working efficiency of the excavator, improves the stability of the surrounding rock, and the blasting weakening distance is relatively long, effectively improves the continuity of the excavation. BRIEF DESCRIPTION OF DRAWINGS

[0035] The drawings accompanying the specification of this application form a part hereof, serve to provide further understanding of the application, and together with the description of the exemplary embodiments of the application and explanations thereof, serve to explain the application, and do not constitute an improper limitation on the application.

[0036] Figure 1 is a flow chart of the coal mine rock roadway super deep hole blasting-mechanical combined tunneling method of the present application;

[0037] Figure 2 is a blasting crack propagation plane shape diagram;

[0038] Figure 3 is a cross section schematic diagram of the auxiliary transport main roadway in the embodiment of the present application;

[0039] Figure 4 is a blast hole position diagram of the five super deep blast holes in the embodiment of the present application;

[0040] Figure 5 is a plugging schematic diagram of the super deep blast hole in the embodiment of the present application;

[0041] wherein:

[0042] 1-explosive, 2-plugging bag, 3-grouting pipe, 4-back grouting pipe, 5-grouting pump, 6-swelling rapid-setting cement supply tank, 7-detonator, 8-detonator leg line. DETAILED DESCRIPTION

[0043] It should be noted that the following detailed description is illustrative only and is intended to provide further description of the present application. 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.

[0044] It should be noted that the terms used herein are only intended to describe specific embodiments and are not intended to limit the exemplary embodiments according to the present application. As used herein, the singular form is intended to include the plural form unless the context clearly indicates otherwise, and it should also be understood that when the terms "comprise" and / or "include" are used in the specification, they indicate the presence of the features, steps, operations, devices, components and / or combinations thereof.

[0045] In the present application, the terms such as "upper", "lower", "bottom", "top" and the like indicate the orientation or positional relationship shown in the drawings, which is only a relationship word determined for the purpose of describing the structural relationship of the components or elements of the present application, and is not intended to specify any component or element in the present application, and cannot be understood as a limitation of the present application.

[0046] In the present application, the terms such as "connected", "connected" and the like should be understood broadly, which means that it can be fixedly connected, integrally connected or detachably connected; it can be directly connected or indirectly connected through an intermediate medium. For related researchers or technicians in the art, the specific meaning of the above terms in the present application can be determined according to the specific circumstances, and cannot be understood as a limitation of the present application.

[0047] The application will be further described below in conjunction with the drawings and examples.

[0048] As Figure 1 shown in the drawings, a coal mine rock roadway super deep hole blasting-mechanical combined tunneling method comprises the following steps:

[0049] Step 1, collect and analyze the engineering, hydrogeological data and rock roadway design data of the tunneling rock roadway, and test and analyze the basic mechanical properties of the rock of the tunneling rock roadway and the ground stress condition; wherein the specific implementation of this step is the prior art, which will not be described here;

[0050] Step 2, determine the number of super deep blast holes that need to be drilled on the rock roadway tunneling section;

[0051] Specifically, the step 2 comprises the following sub-steps:

[0052] Step 21, determine the diameter D and depth of the super deep blast hole;

[0053] Step 22, determine the weakening area S1 of a single super deep blast hole, S1 = 350D 2 ~ 650D 2 Under the ground stress condition, the blasting crack propagation plane shape is elliptical, as Figure 2 shown, the long axis is parallel to the maximum principal stress σ1, and the short axis is parallel to the minimum principal stress σ3;

[0054] Step 23, calculate the number N of super deep blast holes that need to be drilled on the rock roadway tunneling section, N = [S / S1] + 1, S is the section area of the rock roadway tunneling section, and [S / S1] represents the maximum integer not exceeding S / S1.

[0055] Specifically, in the step 21, the diameter D of the super deep blast hole is not greater than 110 mm.

[0056] Specifically, in the step 21, the depth of the super deep blast hole is not less than 30 m.

[0057] Step 3, use a drilling machine to drill each super deep blast hole on the rock roadway tunneling section along the direction perpendicular to the tunneling section;

[0058] Specifically, take the center point of the super deep blast hole on the rock roadway tunneling section as the center to draw an inscribed circle of the rock roadway tunneling section contour line, and the radius of the inscribed circle is not less than 13D;

[0059] The connecting line of the center points of any two super deep blast holes on the rock roadway tunneling section is not parallel to the rock roadway bottom edge and the rock roadway side edge straight wall, that is, all the super deep blast holes are staggered in the horizontal direction and the vertical direction, so as to realize the uniformity of the weakening of the super deep blast hole to the rock roadway tunneling section;

[0060] The hole spacing between any ultra-deep blasthole and other ultra-deep blastholes on the rock tunnel excavation section ranges from 15D to 35D.

[0061] Specifically, the vertical distance between the center points of any two ultra-deep blastholes on the rock tunnel excavation section along the extension direction of the straight wall of the rock tunnel side and the horizontal distance along the extension direction of the bottom edge of the rock tunnel shall not be less than 150 mm.

[0062] Step 4: Fill each ultra-deep blasthole with explosives and plug it;

[0063] Specifically, in step 4, the blasting uncoupling coefficient is not greater than 1.5.

[0064] Specifically, in step 4, the plugging length of the ultra-deep blasthole is L, L≥L0, L0 is the larger value of 90D and L1, D is the diameter of the ultra-deep blasthole, and L1 is one third of the depth of the ultra-deep blasthole;

[0065] The plugging material for ultra-deep blastholes is expansive quick-setting cement.

[0066] Step 5: Determine the detonation sequence and detonate the explosives in each ultra-deep blasthole in sequence to weaken the rock within the excavation path.

[0067] Specifically, in step 5, the method for determining the detonation sequence is:

[0068] Determine the surrounding rock areas of the tunnels that need to be protected, and determine the distance values ​​between each ultra-deep blasthole and the surrounding rock areas of the tunnels that need to be protected. The order of the distance values ​​from low to high is the detonation order of the ultra-deep blastholes.

[0069] Step 6: Use a tunnel boring machine to excavate.

[0070] Specifically, in step 6, the cutting path of the tunnel boring machine is perpendicular to the expansion direction of the blasting cracks during tunneling.

[0071] Example:

[0072] This embodiment takes a coal mine auxiliary transport tunnel as an example. The auxiliary transport tunnel is entirely arranged in sandstone, and the rock strength is relatively high. The traditional excavation method is inefficient, so the ultra-deep hole blasting-mechanical combined excavation method of the coal mine rock tunnel of this application is adopted.

[0073] The cross section of the auxiliary transport tunnel is semicircular arch. Figure 3 As shown, the tunnel is 5700mm wide and 4650mm high, of which the side straight walls are 1800mm high and the semicircular arch is 2850mm high.

[0074] The ultra-deep hole blasting-mechanical combined excavation method for rock tunnels of the present application comprises the following steps:

[0075] Step 1, collect the engineering, hydrogeological data and rock roadway design data of the auxiliary haulage main roadway, test and analyze the basic mechanical properties of the rock of the auxiliary haulage main roadway and the ground stress condition;

[0076] Step 2, according to the data in step 1, design the blasting parameters, and finally design the hole depth of the super deep blast hole as 30m and the diameter D as 90mm;

[0077] Then according to the weakening area of the single super deep blast hole, take S1 = 630D 2 , and calculate the number N of the super deep blast holes needed to be drilled on the excavation section of the auxiliary haulage main roadway as 5;

[0078] Step 3, use the drilling machine to drill 5 super deep blast holes on the excavation section of the auxiliary haulage main roadway along the direction perpendicular to the excavation section;

[0079] The 5 super deep blast holes are K1, K2, K3, K4 and K5 respectively, and the blast hole positions are as shown in Figure 4 ;

[0080] The vertical distance between K1 and the bottom edge of the auxiliary haulage main roadway is 3000mm, and the vertical distance between K1 and the left straight wall is 1700mm; the vertical distance between K2 and the bottom edge of the auxiliary haulage main roadway is 2600mm, and the vertical distance between K2 and the right straight wall is 1400mm; the vertical distance between K3 and the bottom edge of the auxiliary haulage main roadway is 2200mm, and the vertical distance between K3 and the right straight wall is 2700mm; the vertical distance between K4 and the bottom edge of the auxiliary haulage main roadway is 1500mm, and the vertical distance between K4 and the left straight wall is 1500mm; the vertical distance between K5 and the bottom edge of the auxiliary haulage main roadway is 1200mm, and the vertical distance between K5 and the right straight wall is 1600mm.

[0081] Among them, take the K1 center point as the center to make an incircle of the auxiliary haulage main roadway contour line, the radius of the incircle is 1187.9mm, which is greater than 13D, 13D is 1170mm;

[0082] Take the K2 center point as the center to make an incircle of the auxiliary haulage main roadway contour line, the radius of the incircle is 1193.9mm, which is greater than 13D, 13D is 1170mm

[0083] Take the K3 center point as the center to make an incircle of the auxiliary haulage main roadway contour line, the radius of the incircle is 2200mm, which is greater than 13D, 13D is 1170mm;

[0084] Take the K4 center point as the center to make an incircle of the auxiliary haulage main roadway contour line, the radius of the incircle is 1500mm, which is greater than 13D, 13D is 1170mm;

[0085] Take the K5 center point as the center to make an incircle of the auxiliary haulage main roadway contour line, the radius of the incircle is 1200mm, which is greater than 13D, 13D is 1170mm.

[0086] The hole spacing between K1 and K2 is 2630.6mm, which is 29.23D;

[0087] The hole spacing between K1 and K3 is 1526.4mm, which is 16.96D;

[0088] The hole spacing between K1 and K4 is 1513.3mm, which is 16.81D;

[0089] The hole spacing between K1 and K5 is 3000.0mm, which is 33.33D;

[0090] The hole spacing between K2 and K3 is 1360.1mm, which is 15.11D;

[0091] The hole spacing between K2 and K4 is 3008.3mm, which is 33.43D;

[0092] The hole spacing between K2 and K5 is 1414.2mm, which is 15.71D;

[0093] The hole spacing between K3 and K4 is 1655.3mm, which is 18.39D;

[0094] The hole spacing between K3 and K5 is 1486.6mm, which is 16.52D;

[0095] The hole spacing between K4 and K5 is 2617.3mm, which is 29.08D.

[0096] The vertical distance between the center points of K1 and K2 along the extension direction of the straight wall of the side edge of the rock roadway is 400mm, and the horizontal distance along the extension direction of the bottom edge of the rock roadway is 2600mm, both of which are greater than 150mm;

[0097] The vertical distance between the center points of K1 and K3 along the extension direction of the straight wall of the side edge of the rock roadway is 800mm, and the horizontal distance along the extension direction of the bottom edge of the rock roadway is 1300mm, both of which are greater than 150mm;

[0098] The vertical distance between the center points of K1 and K4 along the extension direction of the straight wall of the side edge of the rock roadway is 1500mm, and the horizontal distance along the extension direction of the bottom edge of the rock roadway is 200mm, both of which are greater than 150mm;

[0099] The vertical distance between the center points of K1 and K5 along the extension direction of the straight wall of the side edge of the rock roadway is 1800mm, and the horizontal distance along the extension direction of the bottom edge of the rock roadway is 2400mm, both of which are greater than 150mm;

[0100] The vertical distance between the center points of K2 and K3 along the direction of the straight wall extending along the side edge of the rock roadway is 400 mm, and the horizontal distance along the direction of the straight wall extending along the bottom edge of the rock roadway is 1300 mm, both of which are greater than 150 mm;

[0101] The vertical distance between the center points of K2 and K4 along the direction of the straight wall extending along the side edge of the rock roadway is 1100 mm, and the horizontal distance along the direction of the straight wall extending along the bottom edge of the rock roadway is 2800 mm, both of which are greater than 150 mm;

[0102] The vertical distance between the center points of K2 and K5 along the direction of the straight wall extending along the side edge of the rock roadway is 1400 mm, and the horizontal distance along the direction of the straight wall extending along the bottom edge of the rock roadway is 200 mm, both of which are greater than 150 mm;

[0103] The vertical distance between the center points of K3 and K4 along the direction of the straight wall extending along the side edge of the rock roadway is 700 mm, and the horizontal distance along the direction of the straight wall extending along the bottom edge of the rock roadway is 1500 mm, both of which are greater than 150 mm;

[0104] The vertical distance between the center points of K3 and K5 along the direction of the straight wall extending along the side edge of the rock roadway is 1000 mm, and the horizontal distance along the direction of the straight wall extending along the bottom edge of the rock roadway is 1100 mm, both of which are greater than 150 mm;

[0105] The vertical distance between the center points of K4 and K5 along the direction of the straight wall extending along the side edge of the rock roadway is 300 mm, and the horizontal distance along the direction of the straight wall extending along the bottom edge of the rock roadway is 2600 mm, both of which are greater than 150 mm.

[0106] Step 4, loading explosives into each super-deep blast hole and plugging.

[0107] Each super-deep blast hole has a loading length of 20 m, a plugging length of 10 m, and the plugging material uses expanded rapid-setting cement. The plugging diagram of the super-deep blast hole is shown in Figure 5 After the explosives 1 are installed in the super-deep blast hole, the detonator leg wire 8 of the detonator 7 penetrates out of the super-deep blast hole, and then the sealing bag 2 is arranged at the hole opening of the super-deep blast hole, the sealing bag 2 is provided with a grouting pipe 3 and a back grouting pipe 4, the end of the grouting pipe 3 penetrating out of the sealing bag 2 is connected with the outlet of the grouting pump 5, the inlet of the grouting pump 5 is connected with the expanded rapid-setting cement supply tank 6, and the end of the back grouting pipe 4 located in the sealing bag 2 extends to the bottom end of the plugged end in the super-deep blast hole. The grouting pump 5 is started to inject the expanded rapid-setting cement into the super-deep blast hole through the grouting pipe 3, and the grouting is stopped when the expanded rapid-setting cement comes out of the outlet of the back grouting pipe 4.

[0108] Step 5, determining the detonation sequence, detonating the explosives in each super-deep blast hole in turn, and blasting and weakening the rock in the range of the excavation path.

[0109] Considering the support problem of the semi-circular arch, the semi-circular arch of the auxiliary haulage roadway is the part of the rock roadway surrounding rock which needs to be protected, the vertical distance between K1 and the semi-circular arch of the auxiliary haulage roadway is 1407.7mm, the vertical distance between K2 and the semi-circular arch of the auxiliary haulage roadway is 1653.6mm, the vertical distance between K3 and the semi-circular arch of the auxiliary haulage roadway is 2446.1mm, the vertical distance between K4 and the semi-circular arch of the auxiliary haulage roadway is 2810.0mm, and the vertical distance between K5 and the semi-circular arch of the auxiliary haulage roadway is 3161.3mm. Therefore, the blasting is sequentially initiated in the order of K1, K2, K3, K4 and K5, that is, the K1 blast hole is initiated first, and the K5 blast hole is initiated last, so as to prevent the blast fracture zone formed by the front initiation blast hole from hindering the seismic wave of the subsequent initiation blast hole.

[0110] The length of the foot line of the required electronic detonator for the coal mine is 15m, and the initiation mode is parallel, that is, 3 detonators are connected in parallel in the hole, and the holes are connected in parallel; the delay interval is that the electronic detonators of the K1, K2, K3, K4 and K5 blast holes are respectively set to have delay times of 0ms, 25ms, 50ms, 75ms and 100ms.

[0111] The personnel and equipment are evacuated to the safe range of the blasting, and the electronic detonator is initiated by using a special initiator.

[0112] After the blasting, the ventilation is strengthened, and after 30 minutes of ventilation, the construction personnel enter the heading face to check the safety of the roof and the two sides, and process the floating stone of the roof and the two sides.

[0113] Step 6: The heading machine is used for heading.

[0114] Specifically, in the step 6, the cutting path of the heading machine is perpendicular to the extension direction of the blast crack when the heading machine is heading.

[0115] According to the shape of the roadway and the lithology, the EBZ260 type heading machine is selected. The EBZ260 type heading machine is opened to the heading face, and after reaching the working position, the scraper conveyor is started and the heading is started. The heading machine cuts from the middle of the roadway arch baseline to the right, and then cuts from the right to the left spirally upward. When the cutting reaches the top of the roadway, the roof is temporarily supported and primary supported, and then the heading machine cuts from top to bottom and left to right reciprocally until the designed floor height. The heading process is repeated until the boundary of the pre-splitting affected area of the super-deep hole blasting is reached.

[0116] Before each time the heading machine starts to head, it is checked whether there is a blind or residual blast hole in the single heading depth of the heading face, and the blast crack extension is observed. The cutting head cuts in a direction perpendicular to the extension direction of the blast crack.

[0117] The application first blasts the rock in the tunneling path range by super-deep hole blasting, reduces the integrity of the rock in the tunneling path range, and then uses a tunneling machine to tunnel, which has low overall investment cost, can tunnel according to the design, the tunneling operation can be interrupted, and has high average tunneling speed; the super-deep hole blasting is used to reduce the integrity of the rock in the tunneling path range, avoids the rock splashing, over-blasting and under-excavation in the existing blasting tunneling method, the rock pre-splitting effect caused by the super-deep hole blasting improves the rock tunneling footage, improves the adaptability of the tunneling machine to the engineering geological conditions, effectively reduces the wear of the cutting tooth of the tunneling machine, the dust amount and the probability of the spark generated by the collision between the cutting tooth and the rock, improves the working efficiency of the tunneling machine, improves the stability of the surrounding rock, and the blasting weakening distance is long, effectively improves the continuity of the tunneling.

[0118] Although the specific embodiments of the application are described above with reference to the drawings, the application is not limited thereto, and those skilled in the art should understand that various modifications or changes made on the basis of the technical solutions of the application without creative labor are still within the protection scope of the application.

Claims

1. A coal mine rock tunnel ultra-deep hole blasting-mechanical combined excavation method, characterized in that: The following steps are involved: Step 1: Collect and analyze the engineering, hydrogeological and design data of the rock tunnel to be excavated, and test and analyze the basic mechanical properties and ground stress conditions of the rock in the rock tunnel to be excavated; Step 2: Determine the number of ultra-deep blastholes to be drilled on the rock tunnel excavation section; Step 3: Use a drilling rig to drill each ultra-deep blasthole on the rock tunnel excavation section in a direction perpendicular to the excavation section; Step 4: Fill each ultra-deep blasthole with explosives and plug it; Step 5: Determine the detonation sequence and detonate the explosives in each ultra-deep blasthole in sequence to weaken the rock within the excavation path. Step 6, using a tunnel boring machine to excavate; The step 2 includes the following sub-steps: Step 21, determining the diameter D and depth of the ultra-deep blasthole; Step 22: Determine the weakened area S1 of a single ultra-deep blasthole, S1 = 350D 2 ~650D 2 ; Step 23, calculating the number N of ultra-deep blastholes that need to be drilled on the rock roadway excavation section, where N = [S / S1] + 1, where S is the cross-sectional area of ​​the rock roadway excavation section, and [S / S1] represents the largest integer that does not exceed S / S1; An inscribed circle of the rock tunnel excavation section contour line is drawn with the center point of the super-deep blasthole on the rock tunnel excavation section as the center, and the radius of the inscribed circle is not less than 13D; The line connecting the center points of any two ultra-deep blastholes on the rock tunnel excavation section is not parallel to the bottom edge of the rock tunnel or the vertical wall of the rock tunnel side; The hole spacing between any ultra-deep blasthole and other ultra-deep blastholes on the rock roadway excavation section ranges from 15D to 35D; In step 5, the method for determining the detonation sequence is: Determine the surrounding rock areas of the tunnels that need to be protected, and determine the distance values ​​between each ultra-deep blasthole and the surrounding rock areas of the tunnels that need to be protected. The order of the distance values ​​from low to high is the detonation order of the ultra-deep blastholes.

2. The method for ultra-deep hole blasting and mechanical combined excavation of coal mine rock tunnels according to claim 1, characterized in that: In step 21, the diameter D of the ultra-deep blasthole is not greater than 110 mm.

3. The method for ultra-deep hole blasting and mechanical combined excavation of coal mine rock tunnels according to claim 1, characterized in that: In step 21, the depth of the ultra-deep blasthole is not less than 30m.

4. The method for ultra-deep hole blasting and mechanical combined excavation of a coal mine rock roadway according to claim 1, characterized in that: The vertical distance between the center points of any two ultra-deep blastholes on the rock tunnel excavation section along the extension direction of the straight wall of the rock tunnel side and the horizontal distance along the extension direction of the bottom edge of the rock tunnel shall not be less than 150mm.

5. The method for ultra-deep hole blasting and mechanical combined excavation of coal mine rock roadway according to claim 1, characterized in that: In step 4, the blasting uncoupling coefficient is not greater than 1.

5.

6. The method for ultra-deep hole blasting and mechanical combined excavation of coal mine rock roadway according to claim 1, characterized in that: In step 4, the plugging length of the ultra-deep blasthole is L, L≥L0, L0 is the larger value of 90D and L1, D is the diameter of the ultra-deep blasthole, and L1 is one third of the depth of the ultra-deep blasthole; The plugging material for ultra-deep blastholes is expansive quick-setting cement.

7. The method for ultra-deep hole blasting and mechanical combined excavation of coal mine rock tunnels according to claim 1, characterized in that: In step 6, the cutting path of the roadheader is perpendicular to the expansion direction of the blasting cracks during excavation.

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