CN117027928B - Pressure relief drilling backfilling method based on rock burst roadway classification - Google Patents
Pressure relief drilling backfilling method based on rock burst roadway classification Download PDFInfo
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- CN117027928B CN117027928B CN202311127410.8A CN202311127410A CN117027928B CN 117027928 B CN117027928 B CN 117027928B CN 202311127410 A CN202311127410 A CN 202311127410A CN 117027928 B CN117027928 B CN 117027928B
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- 238000000034 method Methods 0.000 title claims abstract description 56
- 238000011049 filling Methods 0.000 claims abstract description 75
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- 238000010008 shearing Methods 0.000 claims description 64
- 238000011156 evaluation Methods 0.000 claims description 26
- 239000003245 coal Substances 0.000 claims description 25
- 238000012544 monitoring process Methods 0.000 claims description 22
- 239000004927 clay Substances 0.000 claims description 21
- 238000006073 displacement reaction Methods 0.000 claims description 21
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- 229920005989 resin Polymers 0.000 claims description 20
- 239000011280 coal tar Substances 0.000 claims description 17
- 238000005065 mining Methods 0.000 claims description 15
- 239000011148 porous material Substances 0.000 claims description 15
- 239000002250 absorbent Substances 0.000 claims description 14
- 238000005086 pumping Methods 0.000 claims description 13
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Classifications
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- E—FIXED CONSTRUCTIONS
- E21—EARTH OR ROCK DRILLING; MINING
- E21F—SAFETY DEVICES, TRANSPORT, FILLING-UP, RESCUE, VENTILATION, OR DRAINING IN OR OF MINES OR TUNNELS
- E21F15/00—Methods or devices for placing filling-up materials in underground workings
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- E—FIXED CONSTRUCTIONS
- E21—EARTH OR ROCK DRILLING; MINING
- E21F—SAFETY DEVICES, TRANSPORT, FILLING-UP, RESCUE, VENTILATION, OR DRAINING IN OR OF MINES OR TUNNELS
- E21F15/00—Methods or devices for placing filling-up materials in underground workings
- E21F15/005—Methods or devices for placing filling-up materials in underground workings characterised by the kind or composition of the backfilling material
-
- E—FIXED CONSTRUCTIONS
- E21—EARTH OR ROCK DRILLING; MINING
- E21F—SAFETY DEVICES, TRANSPORT, FILLING-UP, RESCUE, VENTILATION, OR DRAINING IN OR OF MINES OR TUNNELS
- E21F17/00—Methods or devices for use in mines or tunnels, not covered elsewhere
- E21F17/18—Special adaptations of signalling or alarm devices
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- Engineering & Computer Science (AREA)
- Mining & Mineral Resources (AREA)
- Life Sciences & Earth Sciences (AREA)
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- Geochemistry & Mineralogy (AREA)
- Geology (AREA)
- Investigation Of Foundation Soil And Reinforcement Of Foundation Soil By Compacting Or Drainage (AREA)
Abstract
The invention provides a pressure relief drilling backfill method based on rock burst roadway classification, which uses an in-situ test device, combines the characteristics of pressure relief drilling, can simply and rapidly acquire roadway surrounding rock in-situ parameters, and classifies backfill types of roadways on the basis of comprehensively considering the mechanical properties of the roadway surrounding rock, the deformation parameters of the roadway surrounding rock and the damage condition of the pressure relief drilling. By changing the proportion of the filling materials and grouting pressure, backfilling operation is carried out on the pressure-relief drilling holes, so that the roadway surrounding rock is changed from single-side pressure to triaxial pressure, the drilling pressure relief effect is realized, the integrity of the roadway surrounding rock is not damaged, secondary stress concentration is avoided, the pressure-bearing capacity of the roadway surrounding rock is enhanced, and the long-acting pressure relief requirement of the roadway is met. The filling material can play the roles of gas resistance, water shutoff and fire prevention while enhancing the supporting effect of surrounding rocks of the roadway, and the filling material has the advantages of easily available components, simple manufacturing process, low economic cost and good industrial practicability.
Description
Technical Field
The invention relates to the technical field of mine safety production, in particular to a pressure relief drilling backfilling method based on rock burst roadway classification.
Background
Compared with shallow mining, the deep coal mine is faced with more complex geological structures and stress environments in the mining process, and disaster accidents caused by rock burst are increased and enhanced sharply. In order to prevent rock burst accidents, a method generally adopted at the present stage is to arrange pressure relief drilling holes in surrounding rocks of a roadway, release elastic denaturation performance accumulated in the surrounding rocks of the roadway through deformation of the pressure relief drilling holes, release or transfer of stress is realized, the rock burst risk is eliminated or slowed down, and the roadway is kept stable.
When the roadway deformation is well controlled, the pressure relief drilling hole diameter is smaller, and the influence on the integrity and stability of the surrounding rock of the roadway is weaker. When the deformation of the roadway is large, the pressure relief drilling holes usually have serious influence on the integrity and stability of surrounding rocks of the roadway, and particularly in a large deformation area or a stress concentration area of the roadway, partial pressure relief drilling holes collapse to lose pressure relief effect. In order to achieve the pressure relief effect, a cutting operation is usually carried out on the pressure relief drilling hole of the collapsed hole, but the cutting operation further damages the integrity and stability of surrounding rock of a roadway. In addition, as the coal mining proceeds, if the roadway surrounding rock becomes a goaf or a geological structure boundary isolation zone, part of the pressure relief drilling holes are highly likely to become harmful gas leakage and underground water burst and ignition channels. Therefore, the corresponding pressure relief drilling hole is subjected to targeted backfill hole sealing, so that the purpose of pressure relief can be achieved while the integrity and stability of the roadway surrounding rock are protected, and the method has very important practical significance.
At present, relevant scholars at home and abroad have conducted pressure relief drilling backfill process research, wherein the concrete local backfill strengthening technology is widely popularized and used, and the technology realizes the purpose of hole sealing by prefabricating concrete filling columns matched with the pressure relief drilling hole diameters and filling the prefabricated concrete filling columns into the pressure relief drilling holes. Since pressure relief drilling typically has significant deformation after drilling is completed, the following problems occur during the implementation of this technique: a. the concrete filled column cannot be filled into the pressure relief borehole; b. the concrete filling column cannot form effective contact with the wall of the drilled hole after being filled into the pressure relief drilled hole; c. after filling the pressure relief drilling holes, the pressure relief drilling holes deform and squeeze the concrete filling columns, so that secondary stress concentration of surrounding rocks of the roadway is caused. Therefore, the technology does not have a long-acting pressure relief effect and a plugging effect of resisting harmful gas, avoiding mine water from entering and the like as a hard filling method. Therefore, under the current engineering field requirements, a flexible filling method is needed to solve the technical problems.
Disclosure of Invention
In order to solve the problems in the prior art, the invention provides a pressure relief drilling backfilling method based on rock burst roadway classification.
The technical scheme of the invention is as follows:
the pressure relief drilling backfilling method based on rock burst roadway classification is characterized by comprising the following steps of:
step one, evaluating risk factors of a roadway adjacent area in a scoring mode, adding and summing, and determining a risk index Z of the roadway adjacent area 1 ；
Step two, calculating a deformation index Z of the surrounding rock of the roadway by measuring the deformation of the surrounding rock of the roadway and the absolute deformation of the surrounding rock of the roadway 2 ；
Step three, determining a pressure relief drilling-roadway distance index Z 3 ；
Step four, determining a pressure relief drilling damage rate index Z 4 ；
Step five, based on the indexes obtained in the step one to the step four, the index is calculated by the formula Z=Z 1 Z 2 +Z 3 Z 4 Calculating a comprehensive evaluation index Z of the surrounding rock of the roadway, and classifying the roadway according to the value of the comprehensive evaluation index Z;
and step six, preparing pressure relief drilling filling materials corresponding to the roadway classification, and completing the pressure relief drilling filling operation.
In the first step, the risk factors of the roadway adjacent area include: whether harmful gas in coal bodies in the roadway adjacent area exceeds standard or not; whether the roadway adjacent area is in a water burst area or not; whether coal dust in a roadway adjacent area has ignitability or not; whether the roadway adjacent area is adjacent to the goaf.
The risk factor evaluation scoring method for the roadway adjacent area comprises the following steps: the content of harmful gas in the coal body is not less than national standard, 1 minute is recorded, and the content of harmful gas in the coal body is less than national standard, 0 minute is recorded; the area near the roadway is in the water burst area range, 1 minute, and the area near the roadway is not in the water burst area range, 0 minute; the coal dust has ignition property, which is recorded as 1 minute, and the coal dust has no ignition property, which is recorded as 0 minute; and marking 0.5 minute when the roadway is close to the goaf, and marking 0 minute when the roadway is not close to the goaf.
In the second step, the deformation index Z of the surrounding rock of the roadway is calculated through the following formula 2 ，
The absolute deformation of the roadway is calculated by the following formula,
wherein: average volume weight of gamma-tunnel roof strata, N/m 3 The method comprises the steps of carrying out a first treatment on the surface of the H-the buried depth of the roadway, m; b, designing tunneling width m of a roadway; e-roadway surrounding rock elastic modulus, pa.
In the third step, determining a pressure relief drilling-roadway distance index Z 3 The method comprises the following steps: a. defining a sampling detection object as a pressure relief drilling hole between a mining working surface and a main roadway in the monitoring time; b. dividing the pressure relief drilling sequence into N groups by taking a main roadway as a starting point to the direction of a mining working surface, wherein each group comprises a plurality of pressure relief drilling holes, and the pressure relief drilling holes positioned in the middle position in each group are defined as sample pressure relief drilling holes; c. defining the space relative distance between the sample pressure relief drilling axis and the stope cut coal wall extension straight line as D i The method comprises the steps of carrying out a first treatment on the surface of the d. Defining a pressure relief drilling hole with the largest distance from a main roadway in the monitoring time, wherein the spatial relative distance between the axis of the pressure relief drilling hole and an extension straight line of a coal wall of a cutting hole of a stope is D max The method comprises the steps of carrying out a first treatment on the surface of the e. By the formulaAnd calculating a pressure relief drilling-roadway distance index.
In the fourth step, the pressure relief drilling damage rate index Z 4 The value rule is as follows: the drill failure rate is in the range of 0.0-0.4 and is slight failure, and the drill failure rate index Z 4 Taking 1; the drill failure rate is in the range of 0.4-0.7, is moderate failure, and has a drill failure rate index Z 4 Taking 3; a drilling failure rate of 0.7-1.0, a drilling failure rate index Z 4 Taking 5; wherein, the damage rate of the pressure relief drilling hole is calculated by the following formula,
wherein: n is a collapse position relation coefficient, taking the center of the length of the drill hole as a boundary, taking 1 from the collapse degree of the outer half section of the drill hole to be larger than that of the inner half section, and taking 0.5 from the inner half section.
In the fifth step, the roadway is classified into one type when the comprehensive evaluation index Z is 0-5; the comprehensive evaluation index Z is 6-10 time minutes, and the roadway is classified into two classes; the comprehensive evaluation index Z is 11-15, and the roadway is classified into three categories; and the comprehensive evaluation index Z is more than 15, and the roadway is classified into four categories.
When the roadway is of the same type, the filling materials are prepared from the following components in parts by weight: coal tar: water-absorbent resin: fine clay = 1:2:7, preparing a base material; when the roadway is of the second class, the filling materials are prepared from the following components in percentage by weight: coal tar: water-absorbent resin: fine clay = 1:1:18; when the roadway is of three types, the filling materials are prepared from the following components in percentage by weight: coal tar: water-absorbent resin: fine clay = 2:1:17; when the roadway is of four types, the filling materials are prepared from the following components in percentage by weight: coal tar: water-absorbent resin: fine clay = 1:1:9.
further, the filling operation method of the pressure relief drilling hole comprises the following steps: the filling range of the roadway is the full length of the pressure relief drilling hole, and the grouting pressure is two thirds of the threshold value of the surrounding rock of the hydraulic fracture drilling hole wall; the filling range of the second class roadway is the whole length of the pressure relief drilling hole, and the grouting pressure is one half of the threshold value of the surrounding rock of the hydraulic fracture drilling hole wall; the filling range of the three types of roadways is one third of the depth of the pressure relief drilling hole, when filling, the grouting pipe is penetrated into the bottom of the pressure relief drilling hole, after the grouting pipe is filled into one third of the pressure relief drilling hole, the grouting pipe is moved outwards to one third of the position away from the orifice of the pressure relief drilling hole, grouting is continued until grouting is finished, and grouting pressure is one half of the threshold value of the surrounding rock of the hydraulic fracture drilling hole wall; four types of roadways are filled in the full length of the drill hole, and grouting pressure is one third of the threshold value of the surrounding rock of the wall of the hydraulic fracture drill hole; the initial fracturing pressure of the pumping pressure peak value in the process of hydraulically fracturing the surrounding rock of the roadway is the threshold value of the surrounding rock of the hydraulically fracturing drilling wall.
The backfilling method further comprises a preliminary evaluation step of the surrounding rock of the roadway, and in-situ lithology parameters of the surrounding rock of the roadway are obtained by using an in-situ test device, wherein the in-situ lithology parameters comprise in-situ shear strength, loose bed cohesion, internal friction angle and in-situ elastic modulus.
The in-situ test device comprises a propulsion unit, a fracturing unit and a shearing unit; the pushing unit comprises a hydraulic pump station and a hydraulic drill rod, and is used for conveying the fracturing unit and the shearing unit to a set position in a pressure relief drilling hole, and the hydraulic drill rod can rotate anticlockwise under the pushing of the pumping pressure of the hydraulic pump station and provides torque for the shearing unit; the fracturing unit comprises a front end plugging device, a hydraulic fracturing fluid outlet device and a rear end plugging device, wherein the hydraulic fracturing fluid outlet device is positioned between the front end plugging device and the rear end plugging device, and the hydraulic fracturing fluid outlet device is used for providing hydraulic fracturing impact force for a pressure relief borehole after the front end plugging device and the rear end plugging device expand and seal the pressure relief borehole; the shearing unit comprises an integrated frame, a transmission gear, a transmission rack and a shearing die; the transmission gear, the transmission rack and the shearing die are fixedly arranged in the integrated frame; the transmission gear is arranged at the front end of the hydraulic drill rod and synchronously moves along with the hydraulic drill rod; the transmission rack is meshed with the transmission gear and applies pressure to the shearing die through a side slope vertically arranged on the shearing die; the shearing die acts on a drilling surrounding rock in-situ test piece in the pressure relief drilling.
Further, the shearing unit further comprises a gear shaft, a rack chute sleeve and an adjusting spring; the transmission gear is keyed on a gear shaft, and the gear shaft is fixedly connected with the front end surface of the hydraulic drill rod; the transmission rack is arranged above the transmission gear and is fixed through the rack sliding groove and the rack sliding groove sleeve; the adjusting spring is arranged above the transmission rack and used for further ensuring stable engagement of the transmission gear and the transmission rack.
Further, the in-situ test device also comprises a monitoring feedback unit, wherein the monitoring feedback unit comprises a first displacement sensor arranged at the fracturing unit, a high-pressure pump of the fracturing unit and a second displacement sensor arranged at the shearing unit; the first displacement sensor is arranged at the front end plugging device and the rear end plugging device and is used for monitoring the deformation amount of the plugging device; the second displacement sensor is arranged at the shearing die and is used for monitoring displacement deformation of the shearing die; the first displacement sensor and the second displacement sensor are connected with a computer through a signal transmission line and are used for reading and recording data.
The in situ shear strength τ is calculated by the following formula:
wherein: sigma-shear plane normal stress, pa;
-an internal friction factor;
P s -stabilizing the cracking pressure, pa;
P 0 -pore water pressure or groundwater pressure, pa;
the shear plane normal stress sigma is calculated by the following formula:
wherein: m is the torque output by the drilling tool, N.m;
eta-gear rack structure transmission efficiency,%;
alpha-shearing tool and shearing face included angle, °;
a is the area of the shearing surface, square meter;
r-radius of the transmission gear reference circle, m;
the bulk layer cohesion c is calculated by the following formula:
wherein: p (P) s -stabilizing the cracking pressure, pa;
P 0 -pore water pressure or groundwater pressure, pa;-internal friction angle;
-an internal friction factor;
the internal friction factor is calculated by the following formula
Wherein: m is the torque output by the drilling tool, N.m;
eta-gear rack structure transmission efficiency,%;
alpha-shearing tool and shearing face included angle, °;
a is the area of the shearing surface, square meter;
r-radius of the transmission gear reference circle, m;
P s -stabilizing the cracking pressure, pa;
P 0 -pore water pressure or groundwater pressure, pa; the internal friction angle is calculated by the following formula
Wherein: m-torque output by drilling tool;
eta-gear rack structure transmission efficiency;
alpha-shearing tool and shearing face included angle;
a-shear area;
r-radius of the transmission gear reference circle;
P s -stabilizing the cracking pressure;
P 0 -pore water pressure or groundwater pressure;
the in situ elastic modulus was calculated by the following formula:
wherein: the pumping pressure and Pa of the delta sigma-plugging device are increased linearly and uniformly;
the delta r-plugging device linearly and uniformly increases the variation of radius and m when pumping;
r-radius of the pressure relief borehole, m.
And burying a real-time stress sensor in the filling material in a period from the completion of pressure relief drilling filling to the solidification of the filling material.
The invention has the beneficial effects that:
1. according to the pressure relief drilling backfilling method provided by the invention, an in-situ test device is used, and the characteristics of pressure relief drilling are combined, so that all in-situ parameters of the surrounding rock of the roadway can be simply and rapidly obtained, and the backfilling types of the roadway are classified on the basis of comprehensively considering the mechanical properties of the surrounding rock of the roadway, the deformation parameters of the surrounding rock of the roadway and the damage condition of the pressure relief drilling; the pressure relief drilling operation of the surrounding rock of the roadway is carried out by changing the proportion of the filling material and the grouting pressure value, so that the surrounding rock of the roadway is changed from single-sided pressure to triaxial pressure, the integrity of the surrounding rock of the roadway is not damaged while the pressure relief effect of the drilling is realized, secondary stress concentration is avoided, the bearing capacity of the surrounding rock of the roadway is enhanced, and the long-acting pressure relief requirement of the roadway is met.
2. The filling material provided by the invention is a plastic filling material, can be continuously filled without being influenced by pressure relief drilling deformation, and can keep moderate strength after filling. The filling material can permeate into the cracks of the surrounding rock of the roadway, the supporting effect of the surrounding rock of the roadway is enhanced, and meanwhile, the effects of gas resistance, water shutoff and fire prevention can be achieved, so that the requirements of engineering sites are met. And the filling material has the advantages of easily obtained components, simple and feasible manufacturing process, low economic cost and good industrial practicability.
3. According to the pressure relief drilling backfilling method, the real-time stress monitoring device is buried in the plastic filling material, so that real-time monitoring data of surrounding rock stress can be provided for a coal enterprise anti-impact department, and meanwhile, an exemplary method for monitoring the surrounding rock stress is provided, and the expansion extensibility is high.
Drawings
Fig. 1: a flow diagram of the method of the invention;
fig. 2: the roadway backfill type evaluation method is schematically shown in the invention;
fig. 3: schematic structural diagram of in-situ test device;
fig. 4: a shearing unit structure schematic diagram of the in-situ test device;
fig. 5: a transmission rack nesting structure schematic diagram in the in-situ test device;
fig. 6: schematic diagram of stress state of pressure relief drilling unit body after plastic filling;
fig. 7: schematic diagram of pump pressure change of hydraulic fracturing of pressure relief drilling;
fig. 8: roadway deformation amount schematic diagram.
Detailed Description
A plurality of preparation lanes are tunneled before the production of the coal mine working face, and the invention is described in detail by way of example by taking one preparation lane as an example with reference to the accompanying drawings.
As shown in fig. 1 to 8, the invention provides a rock burst pressure relief drilling backfilling method based on roadway classification, which comprises the following steps of.
S1, acquiring in-situ lithology parameters of roadway surrounding rock, wherein the in-situ lithology parameters comprise in-situ shear strength, loose layer cohesion, internal friction angle and in-situ elastic modulus. By analyzing the in-situ lithology parameters of the surrounding rocks of the roadway, the properties of the surrounding rocks of the roadway can be judged in real time and in the field, and the stress state of the surrounding rocks of the roadway can be primarily evaluated. The in-situ shear strength, cohesion and internal friction angle can be used as evaluation indexes, and compared with a roadway evaluation standard mature in the technical field, the evaluation result is more accurate, and accurate and effective prediction guidance is made for pressure relief drilling and filling operation.
The method specifically comprises the following steps:
s1-1, testing the surrounding rock of the roadway through pressure relief drilling by using an in-situ test device.
The in-situ experiment device comprises a propulsion unit, a fracturing unit, a shearing unit and a monitoring feedback unit.
The propulsion unit comprises a hydraulic pump station, a fixed sleeve and a hydraulic drill rod 11. The fixed sleeve is embedded and arranged at the inlet of the pressure relief drilling hole and is used for supporting the hydraulic drill rod 11 and keeping the hydraulic drill rod 11 stable in the drilling operation process; the hydraulic drill rod 11 passes through the drill rod fixing sleeve, and lubricating oil is smeared between the hydraulic drill rod 11 and the drill rod fixing sleeve, so that the drilling resistance is reduced; after the hydraulic drill rod 11 is penetrated into the hydraulic drilling setting position, the hydraulic drill rod can rotate anticlockwise under the pushing of the pumping pressure of the hydraulic pump station.
The fracturing unit comprises a front end plugging device 21, a hydraulic fracturing fluid outlet device 22 and a rear end plugging device 23. The fracturing mechanism is cylindrical, is fixedly sleeved on the outer wall of the hydraulic drill rod 11 close to the front end face, and moves synchronously with the hydraulic drill rod 11. The front end blocking device 21 and the rear end blocking device 23 preferably use a high strength rubber blocking balloon having a fixed width, preferably in the range of 20-30cm. The hydraulic fracturing fluid outlet device 22 is arranged between the front end plugging device 21 and the rear end plugging device 23 and is an alloy ring with a certain width, and the width is preferably 10-20cm. The alloy ring is connected with a high-pressure pump, liquid outlet holes 24 are distributed on the outer surface of the alloy ring, the high-pressure pump pumps high-pressure fracturing fluid into the alloy ring, and the fracturing fluid is pressed out of the liquid outlet holes 24; the outlet holes 24 are spaced 15-25mm, preferably 20mm apart to obtain a uniform hydraulic fracturing effect; the diameter of the outlet holes 24 is 3-8mm, preferably 5mm, to obtain a better hydraulic fracturing impact force. Opening and closingThe dynamic pressure fracturing unit records the pumping pressure change data of the high-pressure pump in the hydraulic fracturing process, and fig. 7 shows a schematic diagram of the pumping pressure change of the hydraulic fracturing of the pressure relief drilling hole, wherein the characters in the diagram have the following meanings: p (P) 0 -testing the pore water pressure in the pressure relief borehole; p (P) b -an initial fracturing pressure at which hydraulic fracturing fractures the test pore wall; p (P) s -hydraulic pressure of the cleaving liquid into the pressure-releasing borehole wall surrounding rock to cleave it continuously; p (P) s0 Stopping the pressure maintained on the pressure gauge after pressurization; p (P) b0 -pressure to re-open the closed fracture by re-opening the pump after stopping the pressurization.
The shearing unit comprises an integrated frame 31, a transmission gear 32, a transmission rack 33, a rack runner 34, a rack runner sleeve 35, an adjusting spring 36, a rolling bearing 37 and a shearing die 38. Wherein, the transmission gear 32, the transmission rack 33, the rack chute 34, the rack chute sleeve 35, the adjusting spring 36 and the rolling bearing 37 are packaged inside the integrated frame 31, and the integrated frame 31 is preferably made of aluminum alloy, so that the integrated frame has excellent mechanical properties and light and corrosion-resistant overall structure.
The transmission gear 32 is keyed on a gear shaft, the gear shaft is fixedly connected with the front end face of the hydraulic drill rod 11, and when the hydraulic drill rod 11 rotates, the gear shaft drives the transmission gear 32 to synchronously rotate. In order to make the gear shaft work smoothly, it is fixedly mounted inside the integrated frame 31 through the rolling bearing 37.
The transmission rack 33 is meshed with the transmission gear 32, is installed above the transmission gear 32, specifically, right above the central axis of the transmission gear 32, and is fixed through the rack chute 34 and the rack chute sleeve 35. The adjusting spring 36 is arranged right above the transmission rack 33, and the effective engagement of the transmission gear 32 and the transmission rack 33 is further ensured by the adjusting spring 36.
The transmission rack 33 is vertically connected with the side inclined surface of the shearing die 38, and the shearing die 38 acts on the inner wall of the pressure relief drilling hole; the torque of the hydraulic drill rod 11 is applied to the transmission rack 33 through the transmission gear 32, and the rotation torque of the hydraulic drill rod 11 is further converted into pressure applied to the shearing die 38 by the transmission rack 33 along the rack chute 34 through meshing transmission; the angle between the cutting die 38 and the cutting plane is 30 °.
The working principle (or working method) of the shearing die is as follows: rotating the hydraulic drill rod 11 to drive the transmission gear 32 to push the transmission rack 33 and the shearing die 38 to be close to a drilling surrounding rock in-situ test piece in the pressure relief drilling, wherein the surrounding rock in-situ test piece is formed by stepped drilling surrounding rocks formed when progressive unequal diameter drill rods are used for deep drilling expansion of the pressure relief drilling; the rotation moment of the hydraulic drill rod 11 is gradually increased slowly after the hydraulic drill rod is pressed close to the surrounding rock in-situ test piece and compacted, and the hydraulic drill rod is regarded as shear failure when one or more of the following conditions occur, wherein the shear stress reaches a peak value, the shear deformation is increased sharply or the shear deformation is greater than 10% of the in-situ test piece in the horizontal direction; after the shear failure is reached, the application of torsion force by the hydraulic drill rod is terminated, and the torque of the drilling tool during the shear failure is recorded.
The monitoring feedback unit comprises a first displacement sensor arranged at the fracturing unit, a high-pressure pump of the fracturing unit and a second displacement sensor arranged at the shearing unit. The first displacement sensor is arranged at the front end plugging device 21 and the rear end plugging device 23 and is used for monitoring the deformation quantity of the plugging device, namely the radius variation quantity of the plugging device; the second displacement sensor is arranged at the shearing die 38 and is used for monitoring displacement deformation of the shearing die 38; the first displacement sensor and the second displacement sensor are connected with a computer through a signal transmission line and are used for reading and recording data.
The operation of the in situ test apparatus is further described by the following experimental procedure:
a. arranging and installing an in-situ test device, and recording the included angle between a shearing die and a shearing surface, the area of the shearing surface, the radius of a pressure relief drilling hole, the radius of a selected transmission gear reference circle and the average transmission efficiency of a gear and a rack;
b. before the formal test is started, pre-checking is needed, so that the hydraulic drill rod is penetrated into the position where the pressure relief drilling hole is arranged, a plugging device is started to test plugging effect, and the running state of the equipment is confirmed by the slow idle hydraulic drill rod;
c. taking out the in-situ test device from the test pressure relief drilling hole, and repeating the operation to perform the test operation of the next sample pressure relief drilling hole; after test data of a plurality of sample pressure relief drilling holes are obtained, the data are evaluated and screened, for example, an average value is taken, and in-situ lithology parameters of roadway surrounding rocks are respectively calculated through an in-situ lithology parameter calculation formula.
S1-2, calculating the in-situ shear strength tau by the following formula:
wherein: sigma-shear plane normal stress, pa;
-an internal friction factor;
P s -stabilizing the cracking pressure, pa;
P 0 -pore water pressure or groundwater pressure, pa.
The shear plane normal stress sigma is calculated by the following formula:
wherein: m is the torque output by the drilling tool, N.m;
eta-gear rack structure transmission efficiency,%;
alpha-shearing tool and shearing face included angle, °;
a is the area of the shearing surface, square meter;
r-radius of pitch circle of transmission gear, m.
S1-3, calculating the cohesive force c of the loose layer of the roadway surrounding rock through the following formula:
wherein: p (P) s -stabilizing the cracking pressure, pa;
P 0 -pore water pressure or groundwater pressure, pa;
-internal friction angle;
-internal friction factor.
The internal friction factor is calculated by the following formula
Wherein: m is the torque output by the drilling tool, N.m;
eta-gear rack structure transmission efficiency,%;
alpha-shearing tool and shearing face included angle, °;
a is the area of the shearing surface, square meter;
r-radius of the transmission gear reference circle, m;
P s -stabilizing the cracking pressure, pa;
P 0 -pore water pressure or groundwater pressure, pa.
S1-4, calculating an internal friction angle by the following formula
Wherein: m-torque output by drilling tool;
eta-gear rack structure transmission efficiency;
alpha-shearing tool and shearing face included angle;
a-shear area;
r-radius of the transmission gear reference circle;
P s -stabilizing the cracking pressure;
P 0 -pore water pressure or groundwater pressure.
S1-5, calculating the in-situ elastic modulus by the following formula:
wherein: the pumping pressure and Pa of the delta sigma-plugging device are increased linearly and uniformly;
the delta r-plugging device linearly and uniformly increases the variation of radius and m when pumping;
r-radius of the pressure relief borehole, m.
S2, determining a risk index Z of a roadway adjacent area 1 The roadway adjacent area refers to an area radiating from the roadway wall to the interior of the surrounding rock within about 10 meters. The method specifically comprises the following steps:
and evaluating the risk factors of the roadway adjacent area.
Risk factors include:
1. whether the harmful gas in the coal body in the roadway adjacent area exceeds the standard or not, wherein the harmful gas comprises but is not limited to gas;
2. whether the roadway adjacent area is in a water burst area or not;
3. whether coal dust in a roadway adjacent area has ignitability or not;
4. whether the roadway adjacent area is adjacent to the goaf.
Evaluation according to index type X i The scoring was performed as follows:
1. index of harmful gas (X) 1 ): the content of harmful gas in the coal body is not less than national standard, and 1 minute is recorded; content of harmful gas in coal body<National standard, record 0 point. The national standard refers to the code of safety regulations for coal mine, the code of engineering design for gas extraction for coal mine and the like.
2. Index of water inrush condition (X) 2 ): the area near the roadway is in the range of the water burst area, and 1 minute is recorded; the area near the roadway is not in the range of the water burst area, and the score is recorded as 0.
3. Fire condition index (X) 3 ): the coal dust has ignition property and is recorded as 1 minute; the coal dust had no ignitability, and was recorded as 0 minutes.
4. Near goaf condition index (X) 4 ): recording 0.5 minute in a goaf near the roadway; and marking 0 minutes when the roadway adjacent area is not adjacent to the goaf.
Adding and summing the evaluation results of the risk factors to obtain a numerical value which is the risk index Z of the roadway adjacent area 1 。
The roadway hazard index Z is as follows 1 In the example of the calculation of (a),
if: content of harmful gas in coal body<National standard, X 1 =0; the roadway adjacent area is in the range of the water burst area, X 2 =1; the coal dust has ignitability, X 3 =1; near goaf of roadway near area X 4 ＝0.5；
Then: roadway hazard index
S3, determining the deformation index Z of the surrounding rock of the roadway 2 Comprising the following steps:
s3-1, calculating the deformation of surrounding rock of the roadway:
the deformation of the surrounding rock of the roadway can be measured by using a tape measure or other length measuring tools according to the regulations of the coal anchor supporting roadway safety management method of the coal face; and (2) comparing the in-situ lithology parameters obtained in the step (S1) with the design parameters of the end face of the roadway when the roadway is designed, and making a difference, wherein the difference is the deformation of the surrounding rock of the roadway.
S3-2, calculating the absolute deformation of the roadway through the following formula:
wherein: average volume weight of gamma-tunnel roof strata, N/m 3 ；
H-the buried depth of the roadway, m;
b, designing tunneling width m of a roadway;
e-roadway surrounding rock elastic modulus, pa.
S3-3, calculating the deformation index Z of the surrounding rock of the roadway through the following formula 2 ：
In the present step, the step of the method,
1. roadway surrounding rock deformation index Z 2 Also known as roadway relative deflection;
2. the modulus of elasticity E of the surrounding rock of the roadway can also be measured by using a drilling elastometer. The drilling elastic modulus method is a commonly used method for measuring deformation or elastic modulus of surrounding rock, and the principle of the method is that a pair of radial pressure is applied to the wall of a drilling hole by using a piston, a wedge block or a small flexible pressure pillow and the like, and corresponding pore diameter change is measured at the same time, so that the deformation or elastic modulus of the rock mass is calculated.
S4, determining a pressure relief drilling-roadway distance index Z 3 。
The arrangement of the pressure relief drilling is as follows: and pressure relief drilling holes are arranged from the roadway to the mining working surface at intervals along the inner wall of the roadway, and the drilling directions of the pressure relief drilling holes are approximately perpendicular to the axis of the roadway. Because the roadway mining operation is a continuous operation process, the stress state of the pressure relief drilling holes is changed along with the pushing of the mining working face. In order to obtain an accurate pressure relief borehole-roadway distance index, a certain short period of time is defined in the step as a monitoring time, preferably 15-30min, and sampling detection is carried out on the pressure relief borehole in the monitoring time.
S4-1, defining a sampling detection object as pressure relief drilling between the mining working face and the main roadway in the monitoring time.
S4-2, taking a main roadway as a starting point to the direction of a mining working surface, dividing the pressure relief drilling sequence into N groups, wherein each group comprises a plurality of pressure relief drilling holes, and the pressure relief drilling holes positioned in the middle position in each group are defined as sample pressure relief drilling holes.
Preferably, the pressure relief boreholes are divided into 5 groups; if the number of the pressure relief drilling holes contained in each group is an odd number, taking the pressure relief drilling holes in the middle position as sample pressure relief drilling holes; if the number of the pressure relief holes contained in each group is even, taking the average value of parameters obtained by two pressure relief holes positioned at the middle position as a sample pressure relief hole parameter.
S4-3, defining the space relative distance between the sample pressure relief drilling axis and the stope cut coal wall extension straight line as D i . Namely, the junction of the central extension surface of the cutting hole of the stope and the ready roadway to be tested is taken as a starting surface, which is equivalent to the starting section to be evaluated of the roadway, D i The geometric spatial distance between the hole axis of the pressure relief borehole for the sample and the coal roadway mining initiation surface.
S4-4, defining a pressure relief drilling hole with the farthest distance from the main roadway in the monitoring time, wherein the spatial relative distance between the axis of the pressure relief drilling hole and the extension straight line of the coal wall of the cutting hole of the stoping work is D max ；
S4-5, calculating a pressure relief drilling-roadway distance index Z by the following formula 3
In the present step, the step of the method,
if the sample pressure relief drilling is seriously damaged and deformed, carrying out slitting operation or re-drilling on the sample pressure relief drilling;
if the drilling is re-drilled, the pressure relief drilling is re-drilled in the group where the sample pressure relief drilling is located, and the target of the re-drilling is selected from 1-3 drilling holes far away from the direction of the mining working surface.
S5, determining a pressure relief drilling damage rate index Z 4 。
The pressure relief borehole failure rate was calculated by the following formula:
wherein: n is a collapse position relation coefficient, taking the center of the length of the drill hole as a boundary, taking 1 from the collapse degree of the outer half section of the drill hole to be larger than that of the inner half section, and taking 0.5 from the inner half section.
Pressure reliefIndex of failure rate of borehole Z 4 The value rule is as follows:
the drill failure rate is in the range of 0.0-0.4 and is slight failure, and the drill failure rate index Z 4 Taking 1;
the drill failure rate is in the range of 0.4-0.7, is moderate failure, and has a drill failure rate index Z 4 Taking 3;
a drilling failure rate of 0.7-1.0, a drilling failure rate index Z 4 Taking 5.
S6, classifying the roadways, wherein the classifying method comprises the following steps:
s6-1, calculating the comprehensive evaluation index Z of the roadway surrounding rock by the following formula based on the indexes obtained in the steps S2-S5,
Z＝Z 1 Z 2 +Z 3 Z 4
s6-2, classifying the roadways according to a numerical range in which the comprehensive evaluation index Z falls, wherein the roadway comprises one class, two classes, three classes and four classes, and the classification standards are shown in the following table:
| comprehensive evaluation index Z | Roadway classification |
| 0-5 | Class I |
| 6-10 | Class II |
| 11-15 | Three types |
| ＞15 | Four classes |
S7, preparing the pressure relief drilling filling material.
The filling material of the pressure relief drilling hole is a plastic filling material comprising coal tar, fine clay and water-absorbing resin. Wherein, coal tar and fine clay are used as matrixes of filling materials, and water-absorbing resin is used as an additive. The plastic filling material is an oily plastic material, has poor fluidity, good plastic characteristics and good water, gas and flame retarding effects.
Fine clay is an aluminum silicate with particles <2 μm, which is generally formed by silicate minerals after weathering on the earth's surface, and is widely distributed in rock and soil, and is an important mineral raw material. The fine clay is moistened by water to form a mud ball, the mud ball is deformed but not cracked under the action of external force, and the original shape can be kept unchanged after the external force is dissipated, so that the water is not easy to pass through, and the mud ball has good plasticity. Meanwhile, the fine clay can be deformed under a small pressure and can keep the original shape for a long time, and the specific surface area is large, and particles have electronegativity, so that the fine clay also has good physical adsorptivity and surface chemical activity.
The water-absorbing resin is a novel functional polymer material with a large amount of hydrophilic groups, can expand rapidly when meeting water, has a high water-absorbing function of absorbing water which is hundreds to thousands times heavier than the water, and has excellent water-retaining performance even though water is difficult to separate when the water-absorbing resin is pressed once the water-absorbing resin expands into hydrogel.
The filling material configuration operation is carried out in a room temperature environment, and comprises the following steps:
1. weighing a certain weight of coal tar liquid, putting the coal tar liquid into a stirrer, and keeping the stirrer to rotate at a constant speed;
2. weighing a certain weight of fine clay, adding the fine clay into a stirrer in batches, and stirring for a period of time not less than 4H to prepare a uniformly mixed filling material matrix.
3. Weighing a certain weight of water-absorbent resin, keeping a stirrer to stir at a constant speed, and adding the water-absorbent resin into a filling material matrix in batches to prepare the oily filling material.
4. The weight ratio of coal tar, fine clay and water-absorbing resin is adjusted to obtain the type of filling material matched with the roadway classification, and the concrete table is shown as follows:
| comprehensive evaluation index Z | Roadway classification | Type of filler material |
| 0-5 | Class I | Class I |
| 6-10 | Class II | Class II |
| 11-15 | Three types | Class III |
| ＞15 | Four classes | Class IV |
Wherein,
the weight ratio of the class I filling material is as follows: coal tar: water-absorbent resin: fine clay = 1:2:7
The weight ratio of the class II filling material is as follows: coal tar: water-absorbent resin: fine clay = 1:1:18;
the weight ratio of the III-class filling material is as follows: coal tar: water-absorbent resin: fine clay = 2:1:17;
the weight ratio of the IV-class filling material is as follows: coal tar: water-absorbent resin: fine clay = 1:1:9.
s8, determining filling ranges of pressure relief drilling holes and grouting pressure in different roadway classifications, wherein the filling ranges are as follows:
pressure relief drilling of a class of roadways: the filling range is the whole length of the pressure relief drilling hole; the grouting pressure is two thirds of the threshold value of the surrounding rock of the hydraulic fracture borehole wall.
Pressure relief drilling of the class II roadway: the filling range is the whole length of the pressure relief drilling hole; the grouting pressure is one half of the threshold value of the surrounding rock of the hydraulic fracture borehole wall.
Pressure relief drilling of three types of roadways: the filling range is one third of the depth of the pressure relief drilling hole respectively: during filling, the grouting pipe is penetrated into the bottom of the pressure relief drilling hole, after the grouting pipe is filled into one third of the pressure relief drilling hole, the grouting pipe is moved outwards to one third of the position away from the orifice of the pressure relief drilling hole, and grouting is continued until grouting ends; the grouting pressure is one half of the threshold value of the surrounding rock of the hydraulic fracture borehole wall.
Pressure relief drilling of four types of roadways: the filling range is the whole length of the drilling hole; the grouting pressure is one third of the threshold value of the surrounding rock of the hydraulic fracture borehole wall.
In the present step, the step of the method,
1. the calculation method of the hydraulic fracture borehole wall surrounding rock threshold value comprises the following steps: pump pressure peak initial fracturing pressure P in hydraulic fracturing roadway surrounding rock process b Is a hydraulic fracture borehole wall surrounding rock threshold.
2. And embedding a real-time stress monitoring device in the filling material in a period from the completion of filling to the solidification of the filling material. The real-time stress monitoring device is a real-time stress sensor, and the mining intrinsic safety type filling body continuous stress sensor is selected, and the filling material has good cohesiveness and plasticity, so that the coupling effect of the real-time stress sensor and the filling material is good. The real-time stress sensor is connected with the anti-flushing department terminal through a data transmission line, and can synchronously collect and upload pressure monitoring data to the anti-flushing department terminal.
The foregoing has shown and described the basic principles, principal features and advantages of the invention. It will be understood by those skilled in the art that the present invention is not limited to the embodiments described above, and that the above embodiments and descriptions are merely illustrative of the principles of the present invention, and various changes and modifications may be made without departing from the spirit and scope of the invention, which is defined in the appended claims.
Claims (11)
1. The pressure relief drilling backfilling method based on rock burst roadway classification is characterized by comprising the following steps of:
step one, evaluating risk factors of a roadway adjacent area in a scoring mode, adding and summing, and determining a risk index Z of the roadway adjacent area 1 ；
The dangerous factors of the roadway adjacent area comprise: whether harmful gas in coal bodies in the roadway adjacent area exceeds standard or not; whether the roadway adjacent area is in a water burst area or not; whether coal dust in a roadway adjacent area has ignitability or not; whether the roadway adjacent area is adjacent to the goaf or not;
the risk factor evaluation scoring method for the roadway adjacent area comprises the following steps: the content of harmful gas in the coal body is not less than national standard, 1 minute is recorded, and the content of harmful gas in the coal body is less than national standard, 0 minute is recorded; the area near the roadway is in the water burst area range, 1 minute, and the area near the roadway is not in the water burst area range, 0 minute; the coal dust has ignition property, which is recorded as 1 minute, and the coal dust has no ignition property, which is recorded as 0 minute; marking 0.5 score when the roadway is close to the goaf, and marking 0 score when the roadway is not close to the goaf;
step two, calculating a deformation index Z of the surrounding rock of the roadway by measuring the deformation of the surrounding rock of the roadway and the absolute deformation of the surrounding rock of the roadway 2 ；
Calculating the deformation index Z of the surrounding rock of the roadway by the following formula 2 ，
The absolute deformation of the roadway is calculated by the following formula,
wherein: average volume weight of gamma-tunnel roof strata, N/m 3 The method comprises the steps of carrying out a first treatment on the surface of the H-the buried depth of the roadway, m; b, designing tunneling width m of a roadway; e-roadway surrounding rock elastic modulus, pa;
step three, determining a pressure relief drilling-roadway distance index Z 3 ；
Determining a pressure relief borehole-roadway distance index Z 3 The method comprises the following steps: a. defining a sampling detection object as a pressure relief drilling hole between a mining working surface and a main roadway in the monitoring time; b. dividing the pressure relief drilling sequence into N groups by taking a main roadway as a starting point to the direction of a mining working surface, wherein each group comprises a plurality of pressure relief drilling holes, and the pressure relief drilling holes positioned in the middle position in each group are defined as sample pressure relief drilling holes; c. defining the space relative distance between the sample pressure relief drilling axis and the stope cut coal wall extension straight line as D i The method comprises the steps of carrying out a first treatment on the surface of the d. Defining a pressure relief drilling hole with the largest distance from a main roadway in the monitoring time, wherein the spatial relative distance between the axis of the pressure relief drilling hole and an extension straight line of a coal wall of a cutting hole of a stope is D max The method comprises the steps of carrying out a first treatment on the surface of the e. By the formulaCalculating a pressure relief borehole-roadway distance index;
step four, determining a pressure relief drilling damage rate index Z 4 ；
The pressure relief borehole failure rate index Z 4 The value rule is as follows: the drill failure rate is in the range of 0.0-0.4 and is slight failure, and the drill failure rate index Z 4 Taking 1; the drill failure rate is in the range of 0.4-0.7, is moderate failure, and has a drill failure rate index Z 4 Taking 3; a drilling failure rate of 0.7-1.0, a drilling failure rate index Z 4 Taking 5; wherein, the damage rate of the pressure relief drilling hole is calculated by the following formula,
wherein: n is a collapse position relation coefficient, taking the center of the drilling length as a boundary, taking 1 from the outer half section of the drilling to have a collapse degree larger than that of the inner half section, and taking 0.5 from the opposite side;
step five, based on the indexes obtained in the step one to the step four, the index is calculated by the formula Z=Z 1 Z 2 +Z 3 Z 4 Calculating a comprehensive evaluation index Z of the surrounding rock of the roadway, and classifying the roadway according to the value of the comprehensive evaluation index Z;
and step six, preparing pressure relief drilling filling materials corresponding to the roadway classification, and completing the pressure relief drilling filling operation.
2. The pressure relief drilling backfill method based on rock burst roadway classification of claim 1, wherein in the fifth step, the comprehensive evaluation index Z is 0-5 time minute, and the roadway classification is one type; the comprehensive evaluation index Z is 6-10 time minutes, and the roadway is classified into two classes; the comprehensive evaluation index Z is 11-15, and the roadway is classified into three categories; and the comprehensive evaluation index Z is more than 15, and the roadway is classified into four categories.
3. The pressure relief drilling backfilling method based on rock burst roadway classification as claimed in claim 2, wherein when the roadways are of one type, the filling materials are mixed in the following weight ratio: coal tar: water-absorbent resin: fine clay = 1:2:7, preparing a base material; when the roadway is of the second class, the filling materials are prepared from the following components in percentage by weight: coal tar: water-absorbent resin: fine clay = 1:1:18; when the roadway is of three types, the filling materials are prepared from the following components in percentage by weight: coal tar: water-absorbent resin: fine clay = 2:1:17; when the roadway is of four types, the filling materials are prepared from the following components in percentage by weight: coal tar: water-absorbent resin: fine clay = 1:1:9.
4. the pressure relief borehole backfilling method based on rock burst roadway classification as claimed in claim 3, wherein the filling operation method of the pressure relief borehole is as follows: the filling range of the roadway is the full length of the pressure relief drilling hole, and the grouting pressure is two thirds of the threshold value of the surrounding rock of the hydraulic fracture drilling hole wall; the filling range of the second class roadway is the whole length of the pressure relief drilling hole, and the grouting pressure is one half of the threshold value of the surrounding rock of the hydraulic fracture drilling hole wall; the filling range of the three types of roadways is one third of the depth of the pressure relief drilling hole, when filling, the grouting pipe is penetrated into the bottom of the pressure relief drilling hole, after the grouting pipe is filled into one third of the pressure relief drilling hole, the grouting pipe is moved outwards to one third of the position away from the orifice of the pressure relief drilling hole, grouting is continued until grouting is finished, and grouting pressure is one half of the threshold value of the surrounding rock of the hydraulic fracture drilling hole wall; four types of roadways are filled in the full length of the drill hole, and grouting pressure is one third of the threshold value of the surrounding rock of the wall of the hydraulic fracture drill hole; the initial fracturing pressure of the pumping pressure peak value in the process of hydraulically fracturing the surrounding rock of the roadway is the threshold value of the surrounding rock of the hydraulically fracturing drilling wall.
5. A pressure relief borehole backfill method based on rock burst roadway classification as claimed in any one of claims 1 to 4, further comprising a roadway surrounding rock preliminary evaluation step, wherein roadway surrounding rock in-situ lithology parameters are obtained by using an in-situ test apparatus, said in-situ lithology parameters comprising in-situ shear strength, unconsolidated layer cohesion, internal friction angle and in-situ elastic modulus.
6. The pressure relief borehole backfill method based on rock burst roadway classification as claimed in claim 5, wherein said in situ test apparatus comprises a propulsion unit, a fracturing unit and a shearing unit;
the pushing unit comprises a hydraulic pump station and a hydraulic drill rod, and is used for conveying the fracturing unit and the shearing unit to a set position in a pressure relief drilling hole, and the hydraulic drill rod can rotate anticlockwise under the pushing of the pumping pressure of the hydraulic pump station and provides torque for the shearing unit;
the fracturing unit comprises a front end plugging device, a hydraulic fracturing fluid outlet device and a rear end plugging device, wherein the hydraulic fracturing fluid outlet device is positioned between the front end plugging device and the rear end plugging device, and the hydraulic fracturing fluid outlet device is used for providing hydraulic fracturing impact force for a pressure relief borehole after the front end plugging device and the rear end plugging device expand and seal the pressure relief borehole;
the shearing unit comprises an integrated frame, a transmission gear, a transmission rack and a shearing die; the transmission gear, the transmission rack and the shearing die are fixedly arranged in the integrated frame; the transmission gear is arranged at the front end of the hydraulic drill rod and synchronously moves along with the hydraulic drill rod; the transmission rack is meshed with the transmission gear and applies pressure to the shearing die through a side slope vertically arranged on the shearing die; the shearing die acts on a drilling surrounding rock in-situ test piece in the pressure relief drilling.
7. The pressure relief borehole backfill method based on rock burst roadway classification of claim 6, wherein said shear unit further comprises a gear shaft, a rack runner sleeve, and an adjustment spring; the transmission gear is keyed on a gear shaft, and the gear shaft is fixedly connected with the front end surface of the hydraulic drill rod; the transmission rack is arranged above the transmission gear and is fixed through the rack sliding groove and the rack sliding groove sleeve; the adjusting spring is arranged above the transmission rack and used for further ensuring stable engagement of the transmission gear and the transmission rack.
8. The pressure relief borehole backfill method based on rock burst roadway classification of claim 6, wherein said in situ test device further comprises a monitoring feedback unit comprising a first displacement sensor disposed at said fracturing unit, a high pressure pump of said fracturing unit, and a second displacement sensor disposed at said shearing unit; the first displacement sensor is arranged at the front end plugging device and the rear end plugging device and is used for monitoring the deformation amount of the plugging device; the second displacement sensor is arranged at the shearing die and is used for monitoring displacement deformation of the shearing die; the first displacement sensor and the second displacement sensor are connected with a computer through a signal transmission line and are used for reading and recording data.
9. The pressure relief borehole backfill method based on rock burst roadway classification as claimed in claim 8, wherein,
the in situ shear strength τ is calculated by the following formula:
wherein: sigma-shear plane normal stress, pa;
-an internal friction factor;
P s -stabilizing the cracking pressure, pa;
P 0 -pore water pressure or groundwater pressure, pa;
the shear plane normal stress sigma is calculated by the following formula:
wherein: m is the torque output by the drilling tool, N.m;
eta-gear rack structure transmission efficiency,%;
alpha-shearing tool and shearing face included angle, °;
a is the area of the shearing surface, square meter;
r-radius of the transmission gear reference circle, m;
the bulk layer cohesion c is calculated by the following formula:
wherein: p (P) s -stabilizing the cracking pressure, pa;
P 0 -pore water pressure or groundwater pressure, pa;-internal friction angle;
-an internal friction factor;
the internal friction factor is calculated by the following formula
Wherein: m is the torque output by the drilling tool, N.m;
eta-gear rack structure transmission efficiency,%;
alpha-shearing tool and shearing face included angle, °;
a is the area of the shearing surface, square meter;
r-radius of the transmission gear reference circle, m;
P s -stabilizing the cracking pressure, pa;
P 0 -pore water pressure or groundwater pressure, pa; the internal friction angle is calculated by the following formula
Wherein: m-torque output by drilling tool;
eta-gear rack structure transmission efficiency;
alpha-shearing tool and shearing face included angle;
a-shear area;
r-radius of the transmission gear reference circle;
P s -stabilizing the cracking pressure;
P 0 -pore water pressure or groundwater pressure;
10. the method of pressure relief borehole backfill based on rock burst roadway classification of claim 8 wherein said in situ elastic modulus is calculated by the following equation:
wherein: the pumping pressure and Pa of the delta sigma-plugging device are increased linearly and uniformly;
the delta r-plugging device linearly and uniformly increases the variation of radius and m when pumping;
r-radius of the pressure relief borehole, m.
11. The pressure relief borehole backfill method based on rock burst roadway classification of claim 8, wherein a real-time stress sensor is embedded in the filling material during a period from after the completion of the pressure relief borehole filling to before the solidification of the filling material.
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Citations (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| SU1126698A1 (en) * | 1983-09-29 | 1984-11-30 | Ордена Трудового Красного Знамени Научно-Исследовательский Институт Оснований И Подземных Сооружений Им.Н.М.Герсеванова | Method of tunelling deep mine shafts in low-flooded rocks |
| CN104763432A (en) * | 2015-01-27 | 2015-07-08 | 安徽理工大学 | Method for controlling large deformation by releasing pressure of high-stress roadway surrounding rocks |
| CN105631102A (en) * | 2015-12-24 | 2016-06-01 | 河南理工大学 | Numerical simulation determination method of deep high-stress roadway drilling pressure relief parameter |
| CN111608663A (en) * | 2020-04-29 | 2020-09-01 | 临沂矿业集团菏泽煤电有限公司 | Omnibearing pressure relief method for rock burst dangerous roadway of thick coal seam working face |
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Patent Citations (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| SU1126698A1 (en) * | 1983-09-29 | 1984-11-30 | Ордена Трудового Красного Знамени Научно-Исследовательский Институт Оснований И Подземных Сооружений Им.Н.М.Герсеванова | Method of tunelling deep mine shafts in low-flooded rocks |
| CN104763432A (en) * | 2015-01-27 | 2015-07-08 | 安徽理工大学 | Method for controlling large deformation by releasing pressure of high-stress roadway surrounding rocks |
| CN105631102A (en) * | 2015-12-24 | 2016-06-01 | 河南理工大学 | Numerical simulation determination method of deep high-stress roadway drilling pressure relief parameter |
| CN111608663A (en) * | 2020-04-29 | 2020-09-01 | 临沂矿业集团菏泽煤电有限公司 | Omnibearing pressure relief method for rock burst dangerous roadway of thick coal seam working face |
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