CN116181385A - Anchor rod yielding and prestress monitoring integrated device and application method thereof - Google Patents
Anchor rod yielding and prestress monitoring integrated device and application method thereof Download PDFInfo
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- CN116181385A CN116181385A CN202310139778.XA CN202310139778A CN116181385A CN 116181385 A CN116181385 A CN 116181385A CN 202310139778 A CN202310139778 A CN 202310139778A CN 116181385 A CN116181385 A CN 116181385A
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- 238000012544 monitoring process Methods 0.000 title claims abstract description 52
- 238000000034 method Methods 0.000 title claims description 9
- IJGRMHOSHXDMSA-UHFFFAOYSA-N Atomic nitrogen Chemical compound N#N IJGRMHOSHXDMSA-UHFFFAOYSA-N 0.000 claims abstract description 197
- 229910052757 nitrogen Inorganic materials 0.000 claims abstract description 98
- 229910000831 Steel Inorganic materials 0.000 claims abstract description 74
- 239000010959 steel Substances 0.000 claims abstract description 74
- 239000011435 rock Substances 0.000 claims abstract description 42
- 238000009434 installation Methods 0.000 claims abstract description 13
- 230000000694 effects Effects 0.000 claims abstract description 6
- 229910001873 dinitrogen Inorganic materials 0.000 claims abstract description 3
- 239000003381 stabilizer Substances 0.000 claims description 27
- 238000002347 injection Methods 0.000 claims description 17
- 239000007924 injection Substances 0.000 claims description 17
- 239000007789 gas Substances 0.000 claims description 13
- 230000005540 biological transmission Effects 0.000 claims description 10
- 238000010276 construction Methods 0.000 claims description 6
- 238000013461 design Methods 0.000 claims description 6
- 230000033001 locomotion Effects 0.000 claims description 5
- 230000009471 action Effects 0.000 claims description 4
- 230000008859 change Effects 0.000 claims description 3
- 239000002699 waste material Substances 0.000 claims description 3
- 241000252254 Catostomidae Species 0.000 claims description 2
- 230000001360 synchronised effect Effects 0.000 claims description 2
- 230000006835 compression Effects 0.000 claims 1
- 238000007906 compression Methods 0.000 claims 1
- 230000008901 benefit Effects 0.000 abstract description 5
- 210000001503 joint Anatomy 0.000 abstract description 3
- 230000008093 supporting effect Effects 0.000 abstract description 3
- 238000001125 extrusion Methods 0.000 abstract description 2
- 238000004064 recycling Methods 0.000 abstract description 2
- 238000012806 monitoring device Methods 0.000 abstract 1
- 238000005259 measurement Methods 0.000 description 3
- 238000011160 research Methods 0.000 description 3
- 238000010586 diagram Methods 0.000 description 2
- 238000006073 displacement reaction Methods 0.000 description 2
- 239000000463 material Substances 0.000 description 2
- 230000007246 mechanism Effects 0.000 description 2
- 230000002787 reinforcement Effects 0.000 description 2
- 206010040007 Sense of oppression Diseases 0.000 description 1
- 238000004873 anchoring Methods 0.000 description 1
- 230000009286 beneficial effect Effects 0.000 description 1
- 239000012141 concentrate Substances 0.000 description 1
- 230000007547 defect Effects 0.000 description 1
- 238000011161 development Methods 0.000 description 1
- 238000005516 engineering process Methods 0.000 description 1
- 230000002708 enhancing effect Effects 0.000 description 1
- 238000011156 evaluation Methods 0.000 description 1
- 230000002349 favourable effect Effects 0.000 description 1
- 230000003993 interaction Effects 0.000 description 1
- 238000005065 mining Methods 0.000 description 1
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- 238000012360 testing method Methods 0.000 description 1
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- E—FIXED CONSTRUCTIONS
- E21—EARTH OR ROCK DRILLING; MINING
- E21D—SHAFTS; TUNNELS; GALLERIES; LARGE UNDERGROUND CHAMBERS
- E21D21/00—Anchoring-bolts for roof, floor in galleries or longwall working, or shaft-lining protection
- E21D21/0026—Anchoring-bolts for roof, floor in galleries or longwall working, or shaft-lining protection characterised by constructional features of the bolts
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- E—FIXED CONSTRUCTIONS
- E21—EARTH OR ROCK DRILLING; MINING
- E21D—SHAFTS; TUNNELS; GALLERIES; LARGE UNDERGROUND CHAMBERS
- E21D21/00—Anchoring-bolts for roof, floor in galleries or longwall working, or shaft-lining protection
- E21D21/0026—Anchoring-bolts for roof, floor in galleries or longwall working, or shaft-lining protection characterised by constructional features of the bolts
- E21D21/0033—Anchoring-bolts for roof, floor in galleries or longwall working, or shaft-lining protection characterised by constructional features of the bolts having a jacket or outer tube
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- E—FIXED CONSTRUCTIONS
- E21—EARTH OR ROCK DRILLING; MINING
- E21D—SHAFTS; TUNNELS; GALLERIES; LARGE UNDERGROUND CHAMBERS
- E21D21/00—Anchoring-bolts for roof, floor in galleries or longwall working, or shaft-lining protection
- E21D21/02—Anchoring-bolts for roof, floor in galleries or longwall working, or shaft-lining protection having means for indicating tension
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- Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
- Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
- Y02A—TECHNOLOGIES FOR ADAPTATION TO CLIMATE CHANGE
- Y02A10/00—TECHNOLOGIES FOR ADAPTATION TO CLIMATE CHANGE at coastal zones; at river basins
- Y02A10/23—Dune restoration or creation; Cliff stabilisation
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- Geology (AREA)
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Abstract
The invention discloses an anchor rod yielding and prestress monitoring device, and belongs to the technical field of underground engineering support and geotechnical engineering monitoring. Including steel sleeve, nitrogen spring and the atmospheric pressure prestressing force monitor of cover on the stock, steel sleeve's rear end is equipped with and is used for supporting the steel sleeve edge on the anchor eye outside rock mass, the front portion is equipped with the trench with the butt joint of nitrogen spring, nitrogen spring compressibility is good, make the stock produce when underground works rock mass warp and let the pressure effect, when prestressing force applys, high-strength gear nut will drive the atmospheric pressure push head of atmospheric pressure prestressing force monitor, the nitrogen gas in the extrusion atmospheric pressure prestressing force monitor cylinder makes atmospheric pressure value and prestressing force value each other be balanced power, the atmospheric pressure value can be caught by pressure sensor, finally through comprehensive data readout machine, according to the prestressing force numerical value of nitrogen pressure real-time display stock. The device has the advantages of large deformation yielding, recycling, simple and convenient installation, high monitoring precision and the like.
Description
Technical Field
The invention relates to an anchor rod yielding and prestress monitoring integrated device and a using method thereof, and belongs to the technical field of underground engineering support and geotechnical engineering monitoring.
Background
In recent years, with the rapid development of the anchor bolt support technology, the research on the anchor bolt support theory has also been greatly advanced. The decisive role of prestressing in the bolt support is progressively recognized. With respect to the importance of bolt prestressing, it has been widely accepted and appreciated in geotechnical reinforcement projects. In general, the application of the prestressing force is a main measure for the active supporting of the anchor rod on the surrounding rock of the underground engineering such as a roadway, a tunnel, a chamber and the like, and the larger the prestressing force is, the more favorable the active supporting effect of the anchor rod is. Along with the increase of mining resource exploitation intensity and large-scale construction of deep engineering, engineering technical problems that the prestress application value of an anchor rod cannot be intuitively obtained, the applied prestress is easy to lose and the like still exist in complex and difficult engineering environments such as tunnels, chambers and the like. Therefore, in order to deeply study the interaction mechanism of the anchor rod and surrounding rock and evaluate the safe use state of the anchor rod, a more reliable prestress monitoring and retaining device is required for engineering design.
At present, the engineering community has insufficient knowledge of the prestress action of the anchor rod, a mature and unified theoretical system is not formed, research results of the prestress anchor rod at home and abroad mainly concentrate on the aspects of an anchoring system and a rock mass reinforcement mechanism, and research on the anchor rod prestress monitoring and surrounding rock control effect evaluation method is relatively few. At present, a torque wrench, a torque amplifier, an anchor rod installing machine, an anchor rod shaft force dynamometer (a pressure box and a hydraulic pillow) or the size of the prestress applied by an anchor rod is judged according to the deformation of the anchor rod body, but the problems that the size of the prestress of the anchor rod cannot be obtained in real time, the measuring precision is low, the reliability is poor and the like still exist in the method, so that the design guidance of the test result on the anchor rod support is not strong. Meanwhile, the large deformation of surrounding rock in underground engineering can counteract the applied prestress, and the anchor rod body and a monitoring instrument thereof can be damaged, so that an anchor rod yielding structure (device) also develops. The yielding of the existing anchor rod can be mechanically divided into mechanical sliding yielding, yielding pipe (yielding pipe, yielding ring and the like) yielding and yielding depending on yielding elongation of the material. But has poor operability and popularization in engineering application level and certain limitation.
Disclosure of Invention
Technical problems: aiming at the defects of the prior art, the device for monitoring the yielding and prestress of the anchor rod and the application method thereof have the advantages of large deformation yielding, recycling, simple and convenient installation, high monitoring precision and the like.
The technical scheme is as follows: in order to achieve the technical aim, the invention provides the anchor rod yielding and prestress monitoring integrated device which is arranged on an anchor rod, wherein the tail part of the anchor rod, which is positioned outside an anchor hole, is provided with a high-density thread section, the tail part of the anchor rod is sleeved with a nitrogen spring yielding system and an air pressure prestress monitoring system, the nitrogen spring yielding system and the air pressure prestress monitoring system are connected through a sucker, the nitrogen spring yielding system is arranged on the anchor rod section inside the anchor hole, and the air pressure prestress monitoring system is arranged on the high-density thread section outside the anchor hole;
the nitrogen spring yielding system comprises a steel sleeve sleeved on the anchor rod, the front end of the steel sleeve is sealed and only provided with a hole allowing the anchor rod to pass through, the rear end of the steel sleeve is fully opened and provided with a flange-shaped steel sleeve flange, the steel sleeve is inserted into the anchor hole, the steel sleeve flange at the rear end is propped against the wall of a rock body where the anchor hole is positioned, a pair of nitrogen springs are arranged on two sides of the anchor rod in the steel sleeve, the end parts of the nitrogen springs are connected with the inner side of the front end of the steel sleeve, the tail parts of the nitrogen springs are provided with self-locking baffles contacted with the air pressure prestress monitoring system, and the self-locking baffles can resist the nitrogen springs protruding outwards due to deformation of surrounding rocks, so that the purposes of compressing the nitrogen springs and yielding the anchor rod are achieved;
the pneumatic prestress monitoring system comprises a rotatable tray, two cylinders filled with nitrogen and a high-strength gear nut arranged on a high-density thread section at the tail part of an anchor rod, wherein the rotatable tray is of a disc structure with a central opening, the opening of the rotatable tray is connected with the high-density thread section through a bearing connecting pipe, the bottom ends of the two cylinders are symmetrically arranged on a rotating surface of the rotatable tray through bolts, the other rotating surface of the rotatable tray is connected with a flange of a steel sleeve through a sucking disc, and a rotating grip is arranged between the two cylinders through a cross beam; the pneumatic pushing heads are arranged in all the cylinders, the tops of the pneumatic pushing heads are connected with rigid pushing rods, the rigid pushing rods are of special-shaped structures, one ends of the rigid pushing rods are connected with the pneumatic pushing heads, and the other ends of the rigid pushing rods are connected with high-strength gear nuts through high-strength bolts; all the cylinders are provided with air injection holes, the rigid pushing rod is provided with a toothed belt, and the cylinders are provided with pinions matched with the toothed belt so as to ensure the movement track of the rigid pushing rod; a tray nut stabilizer is arranged between the high-strength gear nut and the rotatable tray, so that the relative position of the high-strength gear nut and the rotatable tray after the prestress is applied is fixed;
the bottoms of all the cylinders are provided with pressure sensors, and all the pressure sensors are connected to a comprehensive data reader through built-in data lines;
when the rock mass is deformed, the anchor rod generates a yielding action, and when the prestress is applied, the high-strength gear nut drives the air pressure pushing head of the air pressure prestress monitor to downwards squeeze nitrogen in the air cylinder, so that the air pressure value of the air cylinder is balanced with the prestress value, the air pressure value is acquired by the pressure sensor, and finally, the prestress value of the anchor rod is displayed in real time according to the nitrogen pressure through the comprehensive data readout machine.
Further, the nitrogen spring is of a gas piston structure, and comprises a nitrogen cylinder, a cylinder piston head in the nitrogen cylinder, and a piston transmission rod connected to the cylinder piston head, wherein a clamping groove is formed in the end portion of the nitrogen cylinder, a clamping tenon is arranged on the inner side of the end portion of the steel sleeve, the clamping groove of the end portion of the nitrogen cylinder is quickly connected with the clamping tenon of the end portion of the steel sleeve, and the self-locking baffle contacts with the tail end of the nitrogen spring.
Further, before the air pressure prestress monitor is used, nitrogen with atmospheric pressure is filled into the air cylinder from the air injection hole, the air pressure pushing head is slowly pushed to the top end of the air cylinder by utilizing nitrogen expansion, the air injection hole is closed after the pressure value on the comprehensive data reading machine is adjusted to zero, and the pressure sensor at the moment is defined to be 0.
Further, after the high-strength gear nut is arranged at the tail part of the anchor rod, the tail end of the rigid pushing rod with the head part being an air pressure pushing head is fixed with the high-strength gear nut through two high-strength bolts; specifically, a prestress moment is applied by rotating the grip, and the high-strength gear nut is screwed in along the anchor rod towards the rock body to finish installation; the inner side of the self-locking baffle is provided with an internal thread matched with the high-density thread section, so that the self-locking baffle can move on the anchor rod.
Further, the nitrogen cylinder of nitrogen spring is filled with the nitrogen of an atmospheric pressure, and the nitrogen spring is in the relaxation state of natural extension at normal state, and total length is unanimous with steel sleeve length, and when the rock mass takes place to warp, the rock mass can promote the whole displacement that produces of steel sleeve to anchor eye external normal direction, and the piston transfer line of the self-locking baffle extrusion nitrogen spring of fixing on the stock this moment prevents it to continue to follow steel sleeve and move outward to, under the oppression of steel sleeve, the cylinder piston head can extrude nitrogen in the nitrogen cylinder, and nitrogen spring contracts to alleviate the stock that leads to because of the rock mass warp and be damaged.
Further, the rigid pushing rod comprises a piston rod section which is perpendicular to the cylinder and can move in the cylinder along with the pneumatic pushing head, the end part of the piston rod section is connected with a high-strength gear nut connecting section which is parallel to the piston rod section through a connecting section, the end part of the high-strength gear nut connecting section is connected with a high-strength gear nut through a high-strength bolt, and a toothed belt matched with a pinion is arranged on the high-strength gear nut connecting section, so that the rigid pushing rod can be conveniently and horizontally displaced.
Further, the contact surface of the rotatable tray is connected with the flange of the steel sleeve through a plurality of suckers, the contact surface of the rotatable tray is connected with the flange of the steel sleeve, and the other rotary surface of the rotatable tray is fixed with the air pressure prestress monitor through 4 bolts so as to realize synchronous rotary motion.
Further, a tray nut stabilizer is arranged between the high-strength gear nut and the rotatable tray, the tray nut stabilizer is of a length-adjustable structure and comprises a telescopic rod and a base for installing the telescopic rod, a length fixing knob is arranged on the base, the telescopic rod is used for self-defining adjustment of the length of the tray nut stabilizer, and the length fixing knob is used for fixing the position of the telescopic rod; the end parts of the telescopic rod and the base are respectively provided with a hook which is respectively used for being fixed on the bolt and the high-strength bolt.
Further, the integrated data reader needs to perform addition calculation on the trunk circuit electric signal from the built-in data line, and because the applied prestress and the pressure of nitrogen in the cylinder are a pair of balance forces, the displayed pressure value result is the applied prestress value, the data can change in real time according to the condition of the pressure of nitrogen in the cylinder, and all circuit elements except the integrated data reader are built in the air pressure prestress monitor.
The application method of the anchor rod yielding and prestress monitoring integrated device is characterized by comprising the following steps of:
firstly, arranging anchor holes on a rock body, reaming 0.5-1.0 m of the end parts of the anchor holes to form installation macropores, wherein the sizes of the installation macropores are matched with those of steel sleeves, so that the steel sleeves are tightly contacted with the installation macropores, and the flanges of the steel sleeves are guaranteed to prop against the outer walls of the anchor holes;
placing the anchor rod and the steel sleeve into an anchor hole with a large hole, wherein the outer side of the steel sleeve is tightly attached to the surface of a rock body, and the flange of the steel sleeve plays a role of a tray; a pair of nitrogen springs in a loose and elongated state are placed in a gap between an anchor rod and a steel sleeve, a clamping tenon is abutted with a clamping groove, and a self-locking baffle is fixed at the exposed end of the anchor rod on the sleeve so as to be in light contact with a piston transmission rod of the nitrogen springs;
step three, a rotatable tray is arranged on the self-locking baffle plate, and the air pressure prestress monitor is fixed with the rotatable tray through bolts; connecting an exposed part plug of the built-in data line with a built-in data line port on the integrated data reader, and operating the integrated data reader to initialize data;
opening the gas injection holes at the tops of the two cylinders, injecting nitrogen into the cylinders until the air pressure pushing head is pushed to the top of the cylinders, stopping injecting nitrogen and closing the gas injection holes when the air pressure value on the comprehensive data reading machine is zero, and resetting the data on the comprehensive data reading machine again to prepare for starting to read new data next; installing a high-strength gear nut, fixing the tail end of the rigid pushing rod on the high-strength gear nut by utilizing a high-strength bolt, and then installing a tray nut stabilizer between the high-strength gear nut and the rotatable tray;
step five, loosening a length fixing knob on the tray nut stabilizer, wherein the telescopic rod can be freely telescopic without resistance; starting prestress monitoring, providing a prestress moment for a rotary grip clockwise by a machine, rotating an air pressure prestress monitor, screwing a high-strength gear nut in the direction of a rock body, driving an air pressure push head to squeeze nitrogen in two cylinders to generate pressure, capturing data by a pressure sensor, and transmitting the data to a comprehensive data reader, wherein the comprehensive data reader displays the current prestress value in real time;
step six, observing a prestress value on the comprehensive data reading machine, stopping applying prestress moment after reaching a target prestress, and simultaneously twisting a length fixing knob, wherein the length of a telescopic rod on a tray nut stabilizer is fixed, the whole tray nut stabilizer becomes a rigid jacking column, and the rigid jacking column is clamped between a high-strength gear nut and a rotatable tray, so that the relative positions of the high-strength gear nut and the rotatable tray are maintained, and the application effect of prestress is ensured not to be invalid due to deformation of a rock mass;
step seven, after the prestressing force is applied, the prestressing force condition is needed to be obtained at any time, only the display number of the comprehensive data reader is read, and the prestressing force application condition and the subsequent prestressing force loss condition can be judged through the display data of the comprehensive data reader;
step eight, maintaining the whole state of the system until the project is finished, and setting the display screen of the comprehensive data reader to be in an automatic screen-extinguishing mode, so that unnecessary electric energy waste is reduced; the above considerations are combined: the actual prestress value of the anchor rod is dynamically fed back through real-time monitoring of the anchor rod prestress, so that the prestress condition is ensured to meet the construction design requirement, and safety accidents are avoided.
The beneficial effects are that: the device has the advantages of controlling the early deformation of surrounding rock, monitoring the prestress of the anchor rod in real time, generating large deformation yielding, and enhancing the reliability of anchor rod support and the control effect of the surrounding rock; the magnitude of the prestress of the anchor rod can be obtained in real time, so that the service life of the anchor rod is prolonged, and the probability of safety accidents is reduced. The prestress measured by the device is described by the pressure change amount of nitrogen in two cylinders, and the result has good reliability and high measurement accuracy. Under the measurement cooperation of the cylinder bottom pressure sensor and the out-of-structure comprehensive data reader, the difficulty coefficient of worker operation is reduced, the intuitiveness of the measurement result is enhanced, and the cost of manpower and material resources is greatly saved. All components related to the device have reusability, can be recovered after construction is finished, and can be put into use again in the next project. The intelligent monitoring system has the advantages of simple structure, convenience in operation, high monitoring precision, reusability, good economic benefit and the like, and has wide applicability and popularization in the technical field.
Drawings
FIG. 1 is a schematic view of an anchor hole used in an integrated device for monitoring yielding and prestressing of an anchor rod based on the principle of air pressure;
FIG. 2 is a schematic diagram of an integrated device for monitoring the yielding and pre-stressing of an anchor rod based on the principle of air pressure in an embodiment of the present invention;
FIG. 3 is a schematic view of the nitrogen spring of the present invention;
FIG. 4 is a schematic diagram of the pneumatic prestressing monitor according to the present invention;
fig. 5 is a schematic view of the structure of the retractable tray nut stabilizer of the present invention.
In the figure: the device comprises a 1-anchor rod, a 2-rotary handle, a 3-rigid pushing rod, a 4-pneumatic push head, a 5-cylinder, a 6-toothed belt, a 7-gas injection hole, an 8-integrated data reader, a 9-bolt, a 10-steel sleeve flange, a 11-rotatable tray, a 12-rock mass, a 13-steel sleeve, a 14-trip, a 15-anchor hole, a 16-nitrogen spring, a 17-self-locking baffle, a 18-tray nut stabilizer, a 19-high strength bolt, a 20-built-in data wire, a 21-pressure sensor, a 22-pinion, a 23-high strength gear nut, a 24-high density thread section, a 25-hook, a 26-telescopic rod, a 27-length fixed knob, a 28-piston transmission rod, a 29-cylinder, a 30-nitrogen cylinder and a piston head 31-clamping groove.
Detailed Description
The invention is further described below with reference to examples of embodiments in the accompanying drawings:
the invention relates to an anchor rod yielding and prestress monitoring integrated device and a use method thereof. The nitrogen spring yielding system mainly comprises a steel sleeve 13, a nitrogen spring 16 and a self-locking baffle 17 which resists a piston transmission rod 28 at the tail end of the nitrogen spring, as shown in fig. 2 and 3, the steel sleeve 13 is sleeved on an opening section of the inside of a rock body 12 of the anchor rod 1, two nitrogen springs 16 are installed at a gap between the sleeve and the anchor rod, a clamping groove 31 at the bottom of the spring is aligned with a clamping tenon 14 at the bottom of the sleeve during butt joint, a high-density thread section 24 is distributed on an exposed section of an anchor hole of the anchor rod 1, the self-locking baffle 17 is rotated to a proper position, and the self-locking baffle 17 just sticks to the piston transmission rod 28 of the spring, when the rock body 12 is deformed and the whole body of the anchor rod is driven to displace in the outward normal direction, the nitrogen spring 16 is pressed by the self-locking baffle 17 which is fixed, so that the yielding performance of the spring is released is achieved, the purpose of protecting the anchor rod body is achieved, and the service life and durability of the anchor rod are improved.
The nitrogen spring yielding system comprises a steel sleeve 13 sleeved on the anchor rod 1, wherein the front end of the steel sleeve 13 is sealed and only provided with a hole allowing the anchor rod 1 to pass through, the rear end of the steel sleeve 13 is fully opened and provided with a flange-shaped steel sleeve flange 10, the steel sleeve 13 is inserted into an anchor hole 15, the steel sleeve flange 10 at the rear end is propped against the wall of a rock body 12 where the anchor hole 15 is positioned, a pair of nitrogen springs 16 are arranged in the steel sleeve 13 at two sides of the anchor rod 1, the ends of the nitrogen springs 16 are connected with the inner side of the front end of the steel sleeve 13, the tail part of the nitrogen springs 16 is provided with a self-locking baffle 17 contacted with a pneumatic prestress monitoring system, and the self-locking baffle 17 can resist the nitrogen springs protruding outwards due to surrounding rock deformation, so that the nitrogen springs are compressed, and the purpose of protecting the anchor rod is achieved;
the pneumatic prestress monitoring system comprises a rotatable tray 11, two cylinders 5 filled with nitrogen gas inside and a high-strength gear nut 23 arranged on a high-density threaded section 24 at the tail part of an anchor rod 1, wherein the rotatable tray 11 is of a disc structure with a central opening, the opening of the rotatable tray 11 is connected with the high-density threaded section 24 through a bearing connecting pipe, the bottom ends of the two cylinders 5 are symmetrically arranged on a rotating surface of the rotatable tray 11 through bolts 9, the other rotating surface of the rotatable tray 11 is connected with a steel sleeve flange 10 through a sucking disc, and a rotary grip 2 is arranged between the two cylinders 5 through a cross beam; the pneumatic push heads 4 are arranged in all the cylinders 5, the top parts of the pneumatic push heads 4 are connected with rigid push rods 3, the rigid push rods 3 are of special-shaped structures, one ends of the rigid push rods 3 are connected with the pneumatic push heads 4, and the other ends of the rigid push rods 3 are connected with high-strength gear nuts 23 through high-strength bolts 19; all the cylinders 5 are provided with air injection holes 7, the rigid pushing rod 3 is provided with toothed belts 6, and the cylinders 5 are provided with pinions 22 which are matched with the toothed belts 6 so as to ensure the movement track of the rigid pushing rod 3; a tray nut stabilizer 18 is provided between the high-strength gear nut 23 and the rotatable tray 11, so that the relative position of the high-strength gear nut 23 and the rotatable tray 11 after the prestressing force is applied is fixed;
the bottoms of all the cylinders 5 are provided with pressure sensors 21, and all the pressure sensors 21 are connected to the comprehensive data reader 8 through built-in data lines 20;
when the rock mass is deformed, the anchor rod 1 generates a yielding action, and when the prestress is applied, the high-strength gear nut 23 drives the air pressure pushing head 4 of the air pressure prestress monitor to downwards squeeze nitrogen in the air cylinder 5, so that the air pressure value of the air cylinder 5 is balanced with the prestress value, the air pressure value is acquired by the pressure sensor 21, and finally the prestress value of the anchor rod 1 is displayed in real time according to the nitrogen pressure through the comprehensive data reader 8.
As shown in fig. 1 and 2, holes are drilled in the design positions of the anchor rods 1, the anchor holes 15 need to be reamed, and the size of the anchor holes meets the placement requirement of the steel sleeve 13.
As shown in fig. 2, 4 and 5, a method for using an anchor rod yielding and prestress monitoring integrated device comprises the following steps:
firstly, arranging an anchor hole 15 on a rock body 12, reaming 0.5-1.0 m of the end part of the anchor hole 15 to form an installation large hole, wherein the size of the installation large hole is matched with that of a steel sleeve 13, so that the steel sleeve 13 is tightly contacted with the installation large hole, and the flange 10 of the steel sleeve is ensured to prop against the outer wall of the anchor hole 15;
placing the anchor rod 1 and the steel sleeve 13 into an anchor hole 15 with a large hole, wherein the outer side of the steel sleeve 13 is tightly attached to the surface of the rock mass 12, and the steel sleeve flange 10 plays a role of a tray; a pair of nitrogen springs 16 in a loose and stretched state are placed in the interval between the anchor rod 1 and the steel sleeve 13, the clamping tenons 14 are in butt joint with the clamping grooves 31, and the self-locking baffle 17 is fixed at the exposed end of the anchor rod 1 in the sleeve so as to be in light contact with the piston transmission rod 28 of the nitrogen springs 16;
step three, a rotatable tray 11 is arranged on the self-locking baffle 17, and the air pressure prestress monitor is fixed with the rotatable tray 11 through bolts 9; connecting the plug of the exposed part of the built-in data line 20 with the built-in data line end of the integrated data reader 8, and operating the integrated data reader 8 to initialize data;
step four, opening the gas injection holes 7 positioned at the tops of the two cylinders 5, injecting nitrogen into the cylinders 5 until the gas pressure pushing head 4 is pushed to the top end of the cylinders, stopping injecting the nitrogen and closing the gas injection holes 7 when the gas pressure value on the comprehensive data reader 8 is zero, and then resetting the data on the comprehensive data reader 8 again to prepare for starting reading new data next; installing a high-strength gear nut 23, fixing the end of the rigid pushing rod 3 on the high-strength gear nut 23 by utilizing a high-strength bolt 19, and then installing a tray nut stabilizer 18 between the high-strength gear nut 23 and the rotatable tray 11;
step five, loosening the length fixing knob 27 on the tray nut stabilizer 18, wherein the telescopic rod 26 can be freely telescopic without resistance; starting prestress monitoring, the machine provides prestress moment for the rotary grip 2 clockwise, the rotary air pressure prestress monitor, the high-strength gear nut 23 is screwed into the direction of the rock mass 12 to drive the air pressure push head 4 to squeeze nitrogen in the two air cylinders 5 to generate pressure, data are captured by the pressure sensor 21 and transmitted to the comprehensive data reader 8, and the comprehensive data reader 8 displays the current prestress value in real time;
step six, observing the prestress value on the comprehensive data reader 8, stopping applying prestress moment after reaching the target prestress, simultaneously twisting the length fixing knob 27, fixing the length of the telescopic rod 26 on the tray nut stabilizer 18, enabling the whole tray nut stabilizer 18 to be a rigid prop, clamping between the high-strength gear nut 23 and the rotatable tray 11, keeping the relative positions of the high-strength gear nut 23 and the rotatable tray 11, enabling the high-strength gear nut 23 to apply prestress to the rotatable tray 11 and the steel sleeve flange 10 through the tray nut stabilizer 18, and ensuring that the applying effect of the anchor prestress cannot be invalid due to deformation of the rock mass 12;
step seven, after the prestressing force is applied, the prestressing force condition is needed to be obtained at any time, only the display number of the comprehensive data reader 8 is needed to be read, and the prestressing force application condition and the subsequent prestressing force loss condition can be judged through the display data of the comprehensive data reader 8;
step eight, maintaining the whole state of the system until the project is finished, and setting the display screen of the comprehensive data reader 8 to be an automatic screen-extinguishing mode, so that unnecessary electric energy waste is reduced; the above considerations are combined: the actual prestress value of the anchor rod is dynamically fed back through real-time monitoring of the anchor rod prestress, so that the prestress condition is ensured to meet the construction design requirement, and safety accidents are avoided.
As shown in fig. 2, 4 and 5, the high-strength gear nut 23 is sleeved on the high-density threaded section 24 of the anchor rod 1 to be close to the tray before the pneumatic prestress monitoring system is used, then the pneumatic prestress monitoring system is fixed on the rotatable tray 11 by using four bolts 9, then the starting of the integrated data reader 8 is carried out, compressible nitrogen is injected into the cylinders 5 on two sides through the air injection holes 7 until the air pressure push head 4 is pushed to the cylinder bottom by the expansion of the nitrogen, the air injection is stopped until the number of the integrated data reader 8 shows zero, the air injection holes 7 are closed, the high-strength gear nut 23 is rotated to be in contact with the tail end of the rigid push rod 3 in the direction away from the tray at the moment, the two high-strength bolts 19 are used for fixing, and finally the tray nut stabilizer 18 is arranged between the tray and the nut, and the length fixing knob 27 is released so that the telescopic rod 26 can be freely telescopic without resistance.
When the prestress monitoring starts, the mechanical clockwise twists the rotary grip 2 to provide a prestress moment, so that the high-strength gear nut 23 drives the rigid push rod 3 and the pneumatic push head 4 to compress nitrogen in the two cylinders 5, the variation of the pneumatic pressure is captured by the pressure sensor 21 at the bottom of the cylinders 5, and the signal is finally transmitted into the comprehensive data reader 8 through the built-in data line 20 to carry out addition calculation, wherein the sum of the variation of the pneumatic pressure in the two cylinders 5 is the applied prestress; when the expected prestress application value is reached, the torsion rotation grip 2 is stopped, and the length fixing knob 27 of the tray nut stabilizer 18 is screwed, so that the telescopic rod 26 cannot continue to stretch to form a rigid stable support, the relative position between the nut and the tray is maintained, and the condition that prestress monitoring fails due to deformation of the rock mass 12 and outward expansion displacement is prevented. After the construction is finished, the aim of repeated use can be achieved by simply removing each device.
Claims (10)
1. The utility model provides a stock lets presses and prestressing force monitoring integrated device, sets up on stock (1), its characterized in that: the tail part of the anchor rod (1) positioned outside the anchor hole (15) is provided with a high-density thread section (24), the tail part of the anchor rod (1) is sleeved with a nitrogen spring yielding system and a pneumatic prestress monitoring system, the nitrogen spring yielding system and the pneumatic prestress monitoring system are connected through a sucker, the nitrogen spring yielding system is arranged on the anchor rod section inside the anchor hole (15), and the pneumatic prestress monitoring system is arranged on the high-density thread section (24) outside the anchor hole (15);
the nitrogen spring yielding system comprises a steel sleeve (13) sleeved on the anchor rod (1), the front end of the steel sleeve (13) is sealed and only provided with a hole allowing the anchor rod (1) to pass through, the rear end of the steel sleeve (13) is fully opened and provided with a flange-shaped steel sleeve flange (10), the steel sleeve (13) is inserted into an anchor hole (15), the steel sleeve flange (10) at the rear end is propped against the wall of a rock mass (12) where the anchor hole (15) is positioned, a pair of nitrogen springs (16) are arranged on two sides of the anchor rod (1) in the steel sleeve (13), the end parts of the nitrogen springs (16) are connected with the inner side of the front end of the steel sleeve (13), the tail parts of the nitrogen springs (16) are provided with self-locking baffle plates (17) contacted with the air pressure prestress monitoring system, and the self-locking baffle plates (17) can resist the nitrogen springs protruding outwards due to surrounding rock deformation, so that the nitrogen springs are compressed, and the purpose of protecting the anchor rod is achieved;
the pneumatic prestress monitoring system comprises a rotatable tray (11), two cylinders (5) filled with nitrogen gas inside and a high-strength gear nut (23) arranged on a high-density threaded section (24) at the tail part of an anchor rod (1), wherein the rotatable tray (11) is of a disc structure with a hole in the center, the hole of the rotatable tray (11) is connected with the high-density threaded section (24) through a bearing connecting pipe, the bottom ends of the two cylinders (5) are symmetrically arranged on a rotating surface of the rotatable tray (11) through bolts (9), the other rotating surface of the rotatable tray (11) is connected with a flange (10) of a steel sleeve through a sucking disc, and a rotating grip (2) is arranged between the two cylinders (5) through a cross beam; the pneumatic pushing heads (4) are arranged in all the cylinders (5), the tops of the pneumatic pushing heads (4) are connected with rigid pushing rods (3), the rigid pushing rods (3) are of special-shaped structures, one ends of the rigid pushing rods (3) are connected with the pneumatic pushing heads (4), and the other ends of the rigid pushing rods are connected with high-strength gear nuts (23) through high-strength bolts (19); all the cylinders (5) are provided with air injection holes (7), the rigid pushing rod (3) is provided with toothed belts (6), and the cylinders (5) are provided with pinions (22) matched with the toothed belts (6) so as to ensure the movement track of the rigid pushing rod (3); a tray nut stabilizer (18) is arranged between the high-strength gear nut (23) and the rotatable tray (11), so that the relative position of the high-strength gear nut (23) and the rotatable tray (11) after the prestress is applied is fixed;
the bottoms of all the cylinders (5) are provided with pressure sensors (21), and all the pressure sensors (21) are connected to a comprehensive data reader (8) through built-in data lines (20);
when the rock mass is deformed, the anchor rod (1) generates a yielding action, and when the prestress is applied, the high-strength gear nut (23) drives the air pressure pushing head (4) of the air pressure prestress monitor to downwards squeeze nitrogen in the air cylinder (5), so that the air pressure value of the air cylinder (5) is balanced with the prestress value, the air pressure value is acquired by the pressure sensor (21), and finally the prestress value of the anchor rod (1) is displayed in real time according to the nitrogen pressure through the comprehensive data reader (8).
2. The anchor bar yielding and prestress monitoring integrated device as claimed in claim 1, wherein: the nitrogen spring (16) is of a gas piston structure and comprises a nitrogen cylinder (30), a cylinder piston head (29) in the nitrogen cylinder (30), a piston transmission rod (28) is connected to the cylinder piston head (29), a clamping groove (31) is formed in the end portion of the nitrogen cylinder (30), a clamping tenon (14) is arranged on the inner side of the end portion of the steel sleeve (13), the clamping groove (31) of the end portion of the nitrogen cylinder (30) is quickly connected with the clamping tenon (14) of the end portion of the steel sleeve (13), and the self-locking baffle (17) is in contact with the tail end of the nitrogen spring (16).
3. The anchor bar yielding and prestress monitoring integrated device as claimed in claim 1, wherein: before the air pressure prestress monitor is used, nitrogen with atmospheric pressure is filled into an air cylinder (5) from an air injection hole (7), an air pressure pushing head (4) is slowly pushed to the top end of the air cylinder by utilizing nitrogen expansion, the air injection hole (7) is closed after the pressure value on the comprehensive data reader (8) is adjusted to zero, and the pressure sensor at the moment is defined to be 0.
4. The anchor bar yielding and prestress monitoring integrated device as claimed in claim 1, wherein: after the high-strength gear nut (23) is arranged at the tail part of the anchor rod (1), the tail end of the rigid pushing rod (3) with the head part being an air pressure pushing head (4) is fixed with the high-strength gear nut (23) through two high-strength bolts (19); specifically, a prestress moment is applied by rotating the grip (2), and the high-strength gear nut (23) is screwed in along the anchor rod (1) towards the rock mass (12) to finish installation; the inner side of the self-locking baffle plate (17) is provided with internal threads matched with the high-density thread section (24) so that the self-locking baffle plate can move on the anchor rod (1).
5. The anchor bar yielding and prestress monitoring integrated device as claimed in claim 1, wherein: the nitrogen cylinder (30) of the nitrogen spring (16) is filled with nitrogen with atmospheric pressure, the nitrogen spring (16) is in a natural extension relaxation state in a normal state, the total length is consistent with the length of the steel sleeve (13), when the rock body (12) is deformed, the rock body (12) can push the steel sleeve (13) to integrally displace towards the outer normal direction of the anchor hole (15), at the moment, the self-locking baffle (17) fixed on the anchor rod (1) extrudes the piston transmission rod (28) of the nitrogen spring (16) to prevent the piston transmission rod from continuously moving outwards along with the steel sleeve (13), under the compression of the steel sleeve (13), the cylinder piston head (29) can extrude nitrogen in the nitrogen cylinder (30), and the nitrogen spring (16) is contracted to relieve the damage to the anchor rod (1) caused by the deformation of the rock body (12).
6. The anchor bar yielding and prestress monitoring integrated device as claimed in claim 1, wherein: the rigid pushing rod (3) comprises a piston rod section which is perpendicular to the cylinder (5) and can move in the cylinder (5) along with the pneumatic pushing head (4), the end part of the piston rod section is connected with a high-strength gear nut connecting section which is parallel to the piston rod section through a connecting section, the end part of the high-strength gear nut connecting section is connected with a high-strength gear nut (23) through a high-strength bolt (19), and a toothed belt (6) matched with a pinion (22) is arranged on the high-strength gear nut connecting section, so that the rigid pushing rod (3) can be horizontally displaced conveniently.
7. The anchor bar yielding and prestress monitoring integrated device as claimed in claim 1, wherein: the contact surfaces of the rotatable tray (11) and the steel sleeve flange (10) are connected through a plurality of suckers, the contact surfaces of the rotatable tray (11) and the steel sleeve flange (10) of the steel sleeve (13) are connected, and the other rotary surface of the rotatable tray (11) is fixed with the air pressure prestress monitor through 4 bolts (9) so as to realize synchronous rotary motion.
8. The anchor bar yielding and prestress monitoring integrated device as claimed in claim 1, wherein: the tray nut stabilizer (18) is arranged between the high-strength gear nut (23) and the rotatable tray (11), the tray nut stabilizer (18) is of a length-adjustable structure, the tray nut stabilizer (18) comprises a telescopic rod (26) and a base for installing the telescopic rod (26), the base is provided with a length fixing knob (27), the telescopic rod (26) is used for self-defining adjustment of the length of the tray nut stabilizer (18), and the length fixing knob (27) is used for fixing the position of the telescopic rod (26); the telescopic rod (26) and the end part of the base are respectively provided with a hook (25) which is respectively fixed on the bolt (9) and the high-strength bolt (19).
9. The anchor bar yielding and prestress monitoring integrated device as claimed in claim 1, wherein: the comprehensive data reader (8) needs to perform addition calculation on the trunk circuit electric signals from the built-in data line (20), and because the applied prestress and the nitrogen pressure in the air cylinder (5) are balanced, the displayed pressure value result is the applied prestress value, the data can change in real time according to the condition of the nitrogen pressure in the air cylinder (5), and all circuit elements are arranged in the air pressure prestress monitor except the comprehensive data reader (8).
10. A method of using an integrated device for bolt yielding and prestressing monitoring according to any of claims 1-9, characterized by the steps of:
firstly, arranging an anchor hole (15) on a rock body (12), reaming the 0.5-1.0 m position of the end part of the anchor hole (15) to form an installation large hole, wherein the size of the installation large hole is matched with that of a steel sleeve (13), so that the steel sleeve (13) is tightly contacted with the installation large hole, and the flange (10) of the steel sleeve is ensured to prop against the outer wall of the anchor hole (15);
placing the anchor rod (1) and the steel sleeve (13) into an anchor hole (15) with a large hole, wherein the outer side of the steel sleeve (13) is tightly attached to the surface of a rock mass (12), and the steel sleeve flange (10) plays a role of a tray; a pair of nitrogen springs (16) in a loose and elongated state are placed in the interval between the anchor rod (1) and the steel sleeve (13), the clamping tenons (14) are abutted with the clamping grooves (31), and the self-locking baffle plates (17) are fixed on the exposed ends of the anchor rod (1) in the sleeve so as to be lightly contacted with the piston transmission rods (28) of the nitrogen springs (16);
step three, a rotatable tray (11) is arranged on the self-locking baffle (17), and the air pressure prestress monitor is fixed with the rotatable tray (11) through bolts (9); connecting an exposed part plug of the built-in data line (20) with a built-in data line end on the integrated data reader (8), and operating the integrated data reader (8) to initialize data;
opening the gas injection holes (7) at the tops of the two cylinders (5), injecting nitrogen into the cylinders (5) until the gas pressure pushing head (4) is pushed to the top of the cylinders, stopping injecting the nitrogen and closing the gas injection holes (7) when the gas pressure value on the comprehensive data reader (8) is zero, and then resetting the data on the comprehensive data reader (8) again to prepare for starting reading new data next; installing a high-strength gear nut (23), fixing the tail end of the rigid pushing rod (3) on the high-strength gear nut (23) by utilizing a high-strength bolt (19), and then installing a tray nut stabilizer (18) between the high-strength gear nut (23) and the rotatable tray (11);
step five, loosening a length fixing knob (27) on the tray nut stabilizer (18), wherein the telescopic rod (26) can freely stretch without resistance; starting prestress monitoring, providing a prestress moment for a rotary grip (2) clockwise by a machine, rotating an air pressure prestress monitor, screwing a high-strength gear nut (23) in the direction of a rock mass (12), driving an air pressure push head (4) to squeeze nitrogen in two air cylinders (5) to generate pressure, capturing data by a pressure sensor (21), and transmitting the data to a comprehensive data reader (8), wherein the comprehensive data reader (8) displays the current prestress value in real time;
step six, observing a prestress value on the comprehensive data reading machine (8), stopping applying a prestress moment after reaching a target prestress value, simultaneously tightening a length fixing knob (27), fixing the length of a telescopic rod (26) on a tray nut stabilizer (18), enabling the whole tray nut stabilizer (18) to be a rigid prop, clamping between a high-strength gear nut (23) and a rotatable tray (11), and keeping the relative positions of the two, so that the prestress application effect is ensured not to be invalid due to deformation of a rock mass (12);
step seven, after the prestressing force is applied, the prestressing force condition is needed to be obtained at any time, only the display number of the comprehensive data reader (8) is read, and the prestressing force application condition and the subsequent prestressing force loss condition can be judged through the display data of the comprehensive data reader (8);
step eight, maintaining the whole state of the system until the project is finished, and setting a display screen of the comprehensive data reader (8) to be in an automatic screen-extinguishing mode, so that unnecessary electric energy waste is reduced; the above considerations are combined: the actual prestress value of the anchor rod is dynamically fed back through real-time monitoring of the anchor rod prestress, so that the prestress condition is ensured to meet the construction design requirement, and safety accidents are avoided.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
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| CN202310139778.XA CN116181385A (en) | 2023-02-20 | 2023-02-20 | Anchor rod yielding and prestress monitoring integrated device and application method thereof |
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| CN202310139778.XA CN116181385A (en) | 2023-02-20 | 2023-02-20 | Anchor rod yielding and prestress monitoring integrated device and application method thereof |
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Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN117738744A (en) * | 2024-02-21 | 2024-03-22 | 中国矿业大学(北京) | Intelligent anchor rod pretightening force applying system and method |
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Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN117738744A (en) * | 2024-02-21 | 2024-03-22 | 中国矿业大学(北京) | Intelligent anchor rod pretightening force applying system and method |
| CN117738744B (en) * | 2024-02-21 | 2024-05-28 | 中国矿业大学(北京) | Intelligent anchor rod pretightening force applying system and method |
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