CN111594241A - Shell expansion anchor rod for soft rock and construction method thereof - Google Patents

Shell expansion anchor rod for soft rock and construction method thereof Download PDF

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Publication number
CN111594241A
CN111594241A CN202010412166.XA CN202010412166A CN111594241A CN 111594241 A CN111594241 A CN 111594241A CN 202010412166 A CN202010412166 A CN 202010412166A CN 111594241 A CN111594241 A CN 111594241A
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China
Prior art keywords
shell
anchor rod
expanding
expansion
conical
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Chinese (zh)
Inventor
罗士亮
程良奎
陶燕丽
王哲
虞兴福
戚玉亮
董文澎
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Zhejiang Juneng Geotechnical Anchorage Research Co ltd
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Zhejiang Juneng Geotechnical Anchorage Research Co ltd
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Priority to CN202010412166.XA priority Critical patent/CN111594241A/en
Publication of CN111594241A publication Critical patent/CN111594241A/en
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    • EFIXED CONSTRUCTIONS
    • E21EARTH OR ROCK DRILLING; MINING
    • E21DSHAFTS; TUNNELS; GALLERIES; LARGE UNDERGROUND CHAMBERS
    • E21D21/00Anchoring-bolts for roof, floor in galleries or longwall working, or shaft-lining protection
    • E21D21/0026Anchoring-bolts for roof, floor in galleries or longwall working, or shaft-lining protection characterised by constructional features of the bolts
    • EFIXED CONSTRUCTIONS
    • E02HYDRAULIC ENGINEERING; FOUNDATIONS; SOIL SHIFTING
    • E02DFOUNDATIONS; EXCAVATIONS; EMBANKMENTS; UNDERGROUND OR UNDERWATER STRUCTURES
    • E02D5/00Bulkheads, piles, or other structural elements specially adapted to foundation engineering
    • E02D5/74Means for anchoring structural elements or bulkheads
    • EFIXED CONSTRUCTIONS
    • E21EARTH OR ROCK DRILLING; MINING
    • E21DSHAFTS; TUNNELS; GALLERIES; LARGE UNDERGROUND CHAMBERS
    • E21D20/00Setting anchoring-bolts
    • EFIXED CONSTRUCTIONS
    • E21EARTH OR ROCK DRILLING; MINING
    • E21DSHAFTS; TUNNELS; GALLERIES; LARGE UNDERGROUND CHAMBERS
    • E21D20/00Setting anchoring-bolts
    • E21D20/02Setting anchoring-bolts with provisions for grouting
    • EFIXED CONSTRUCTIONS
    • E21EARTH OR ROCK DRILLING; MINING
    • E21DSHAFTS; TUNNELS; GALLERIES; LARGE UNDERGROUND CHAMBERS
    • E21D21/00Anchoring-bolts for roof, floor in galleries or longwall working, or shaft-lining protection
    • E21D21/008Anchoring or tensioning means

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  • Engineering & Computer Science (AREA)
  • Mining & Mineral Resources (AREA)
  • Structural Engineering (AREA)
  • Life Sciences & Earth Sciences (AREA)
  • General Life Sciences & Earth Sciences (AREA)
  • Geochemistry & Mineralogy (AREA)
  • Geology (AREA)
  • Paleontology (AREA)
  • Civil Engineering (AREA)
  • General Engineering & Computer Science (AREA)
  • Piles And Underground Anchors (AREA)

Abstract

The invention discloses a shell-expanding anchor rod for soft rock, which comprises an expanding shell and an anchor rod, wherein two ends of the expanding shell are respectively provided with an expanding shell inner wedge and a conical top block, and the expanding shell inner wedge and the expanding shell top as well as the conical top block and the expanding shell bottom are in sliding contact; the anchor rod comprises an anchor rod body, one end of the anchor rod body is fixedly provided with a screw rod through a connecting sleeve, the screw rod is in transmission connection with the inner wedge of the expanding shell through threads, and the top of the connecting sleeve is embedded into the conical ejecting block and tightly presses the supporting flange of the conical ejecting block; rotating the anchor rod to drive the inner wedge of the expansion shell and the conical top block to move towards the inside of the expansion shell until the supporting flange of the conical top block is broken, so that the expansion shell piece deforms outwards and expands to the wall of the surrounding rock hole to apply prestress to the rock body; meanwhile, a construction method of the shell expansion anchor rod for soft rock is also provided. The invention has low cost, good anchoring effect and high construction efficiency, and can be well applied to soft rock stratums.

Description

Shell expansion anchor rod for soft rock and construction method thereof
Technical Field
The invention relates to the technical field of geotechnical engineering anchoring support, in particular to a shell-expanding anchor rod suitable for soft rock stratum and a construction method thereof.
Background
In the construction process of underground engineering, mine roadway, railway tunnel, slope protection and military engineering, in order to prevent stratum deformation, collapse and instability, the stratum needs to be reinforced, the adopted main measure is to embed a mortar anchor rod or an anchor rod with an expansion shell head in the stratum, and the stratum forms an integral reinforcing structure by utilizing the tension of the anchor rod and concrete grouting body integrated with the anchor rod, thereby achieving the purpose of controlling deformation.
Compared with the common mortar anchor rod, the prestressed anchor rod body has the following advantages: 1. a rock compression zone is formed by applying prestress on a rock body between the inner anchor head and the outer anchor head; 2) continuously installing prestressed anchor rods in a rock body, and forming a compression bearing layer with a certain thickness in mutually overlapped and crossed compression areas; 3) particularly in tunnel engineering, a compression area formed by the prestressed anchor rods can form a bearing arch of a rock body, and under the action of an arch effect, the self-bearing capacity of the surrounding rock is fully adjusted, and the resistance to the surrounding rock outside the arch is greatly improved. The prestressed anchor rods comprise rapid explosive cartridges, shell-expanding anchor rods and the like. The shell-expanding anchor rod is generally composed of basic components such as an expanding shell, a rod body, a base plate and a nut, and other components such as a ball pad, a grouting pipe, an exhaust pipe, a grout stop plug and a centering device are added when necessary, so that the shell-expanding anchor rod belongs to a mechanical anchor rod capable of being prestressed.
Compare with stock such as quick cartridge, under the condition that drilling depth, body of rod length are equivalent, the rock compression district scope that the shell stock that rises formed is bigger, can provide better anchor effect. Meanwhile, the instantaneity of the expansion shell anchor rod for providing prestress is more advantageous because the anchoring body does not need to be waited for to be solidified, and the grouting anchor rod can be better applied to soft rock stratum environments. The invention patent of application number CN201910265475.6 discloses an extremely soft rock anchor rod structure, which comprises a hollow anchor rod body, a connecting sleeve, a shell expansion anchor head, a grout stop plug, a base plate and a fixing nut, wherein a limit nut is sleeved on one side of the hollow anchor rod body close to the connecting sleeve in a threaded manner, through grooves between the limit nut and the connecting sleeve are formed in the front surface, the rear surface, the upper surface and the lower surface of the hollow anchor rod body, a moving block positioned at the through grooves is arranged inside the hollow anchor rod body, the moving block can move in the limit nut, and the front surface, the rear surface, the upper surface and the lower surface of the moving block are respectively and fixedly connected with a linkage block; the invention has the advantages of good anchor bolt supporting effect and improved anchoring agent injection efficiency, but still has the following problems: the supporting effect of the hollow anchor rod on soft rock is improved, the hollow anchor rod is dependent on the design of supporting ribs, expansion steel and other components arranged on the hollow rod body, the structure is complex, the production cost is high, the outer end of the hollow anchor rod body extends out of an anchor hole after operation is finished, cutting is needed due to factors such as process requirements and safety, construction steps are increased, the operation efficiency is reduced, and continuous and mechanical operation is difficult to achieve.
Disclosure of Invention
In order to overcome the defects of the prior art, the invention aims to provide the shell-expanding anchor rod which is low in cost, good in anchoring effect and high in construction efficiency, can be well applied to soft rock stratums and even different working conditions, and introduces the construction method of the shell-expanding anchor rod for the soft rock.
The purpose of the invention is realized by adopting the following technical scheme:
a shell-expanding anchor rod for soft rock comprises an expanding shell and an anchor rod, wherein an expanding shell inner wedge and a conical top block are respectively arranged at two ends of the expanding shell, and the expanding shell inner wedge and the expanding shell top as well as the conical top block and the expanding shell bottom are in sliding contact; the anchor rod comprises an anchor rod body, one end of the anchor rod body is fixedly provided with a screw rod through a connecting sleeve, the screw rod is in transmission connection with the inner wedge of the expanding shell through threads, and the top of the connecting sleeve is embedded into the conical ejecting block and tightly presses the supporting flange of the conical ejecting block; and rotating the anchor rod to drive the inner wedge of the expansion shell and the conical ejection block to move towards the inside of the expansion shell until the supporting flange of the conical ejection block is broken, so that the expansion shell piece deforms outwards and expands to the wall of the surrounding rock hole to apply prestress to the rock mass.
Furthermore, the shell that rises includes integrated into one piece's the shell connecting portion that rises and set up two sets of shell pieces that rise in shell connecting portion both sides respectively, and every group rises shell piece circumference and sets up on the shell connecting portion that rises, and the shell inboard that rises is formed with first interior conical surface, interior anchor ring and second interior conical surface from top to bottom, and wherein first interior conical surface, second interior conical surface respectively with rise the shape looks adaptation of shell interior wedge, toper kicking block.
Furthermore, the shell inner wedge that rises is the cone nut structure, including the cone, is provided with the through-hole of taking the internal thread in the cone, and the external conical surface of cone and the first interior conical surface that rises the shell are sliding contact.
Furthermore, a through hole is formed in the conical ejecting block, an annular supporting flange matched with the top of the connecting sleeve is arranged above the through hole, and the outer conical surface of the conical ejecting block is in sliding contact with the second inner conical surface of the expanding shell.
Furthermore, the shell that rises adopts split type structure, two sets of shell connecting portions that rise are nested in same shell connecting portion that rises, or same shell connecting portion that rises and one set of integrated into one piece in two sets of shell pieces that rise, or a set of shell piece that rises and the nested setting behind the shell connecting portion that rises of integrated into one piece.
Furthermore, the outer side of the shell expansion sheet is provided with continuously arranged sawteeth.
Furthermore, a base plate and a driving nut are arranged at the end part of the anchor rod body, two ends of the anchor rod body are fixedly installed with the driving nut and a connecting sleeve respectively, and the driving nut is rotated to enable the anchor rod body to rotate and extrude the conical top block through the connecting sleeve; preferably, the drive nut is provided as a blind nut.
Further, an independent extrusion head is arranged at the top of the connecting sleeve.
Furthermore, the anchor rod body is a hollow anchor rod, and a grout outlet is formed in the connecting sleeve.
Further, an anti-seismic box is arranged between the driving nut and the backing plate, and a yielding component is arranged at the end part of the anchor rod body.
The invention also provides a construction method based on the soft rock expansion shell anchor rod, which comprises the following steps:
s1 drilling: drilling an anchor hole in the rock mass through a drill bit;
and (3) mounting the S2 component: inserting a pre-assembled shell expansion anchor rod component into the anchor hole to enable the backing plate to be tightly attached to the rock wall of the anchor hole opening;
s3 anchoring: the driving nut is rotated, the anchor rod body rotates to drive the connecting sleeve and the screw rod to rotate, so that the conical jacking block moves into the anchor hole to apply pretightening force, and the expansion shell inner wedge moves towards the outer side of the anchor hole, and the expansion shell is tightly attached to and fixed on the anchor hole and applies prestress to a rock stratum.
The step S3 includes the following sub-steps:
initial stage of S31: rotating the anchor rod to drive the connecting sleeve to extrude the conical ejecting block inwards to apply pretightening force to the inner part of the expansion shell, and rotating the screw rod to enable the inner wedge of the expansion shell to slide towards the expansion shell, so that the expansion shell pieces are pushed to deform outwards to be attached to the wall of the surrounding rock hole, and even the end parts of a group of the expansion shell pieces at the outer side are inserted into the wall of the surrounding rock hole in a barb manner, so that the expansion shell fixation is completed;
s32 intermediate stage: the anchor rod is continuously rotated, when the torque exceeds a certain value and the acting force of the connecting sleeve exceeds the strength limit of the supporting flange of the conical top block, the supporting flange is broken, and an internal space is made;
s33 end stage: and continuing to rotate the anchor rod, driving the upper end of the anchor rod body to move upwards through the connecting sleeve by the screw rod, elastically extending the anchor rod, and applying axial pretightening force to the inner wedge, the conical jacking block and the expanding shell of the expanding shell, wherein at the moment, the axial pretightening force is transmitted to the rock wall of the anchor hole through the anchor rod body, the driving nut and the base plate, so that effective prestress application action is carried out on the surrounding rock.
Compared with the prior art, the invention has the beneficial effects that:
1. the invention adopts a unique shell expansion structure provided with the shell expansion connecting part, and compared with the common shell expansion structure, the shell expansion structure has the advantages of fewer components, simpler design, easy realization of standardized production, low cost and convenient assembly.
2. The sawtooth structure outside the expansion shell has good adhesive force with the wall of the surrounding rock, particularly, the expansion shell inner wedge, the conical jacking block and the two groups of expansion shell pieces positioned above and below the expansion shell connecting part form an expansion structure tightly attached to the wall of the surrounding rock, and the group of expansion shell pieces positioned below the expansion shell connecting part have the barb effect of being embedded into the soft rock stratum, so that the structural stability can be kept after the expansion shell connecting part is broken, and a good anchoring effect can be obtained on the soft rock stratum.
3. The shell expansion connecting part can also be broken from the strip-shaped groove under the condition that the external force exceeds the strength limit of the shell expansion connecting part, so that the shell expansion sheet is expanded outwards more fully, the soft rock stratum and even different working conditions are better adapted, and the application range is expanded.
4. The invention does not need to cut the exposed part of the anchor rod body, so the construction steps are simpler, and meanwhile, the blind nut structure is adopted by the driving nut, thereby the continuous and mechanical automatic operation is easy to realize, and the working efficiency can be obviously improved.
Drawings
FIG. 1 is a perspective view of the anchoring portion of the soft rock forced expansion shell anchor of the present invention;
FIG. 2 is a cross-sectional view of the anchoring of the expanding anchor rod for soft rock according to the present invention;
FIG. 3 is a sectional view of the anchoring portion of the expandable shell anchor for soft rock according to the present invention with an extrusion head;
FIG. 4 is an overall structure view of the anchor rod for soft rock of the present invention;
FIG. 5 is a structural view of the expansion anchor rod for soft rock of the present invention configured as a hollow anchor rod body;
FIG. 6 is a structural diagram of the anti-seismic box provided with the expansion anchor rod for soft rock according to the invention;
FIG. 7 is a structural diagram of the soft rock casing-expanding anchor rod setting pressure-relieving assembly according to the present invention;
FIG. 8 is a structural diagram of the anti-seismic box and the yielding component arranged on the expansion anchor rod for soft rock according to the invention;
FIG. 9 is a view showing a construction state of the expanding anchor rod for soft rock according to the present invention;
FIG. 10 is a flow chart of the construction of the anchor rod for soft rock of the present invention;
the labels and counterparts in the figures are: 1-shell expanding sheet, 11-shell expanding connecting part, 12-sawtooth, 13-second inner conical surface, 14-inner annular surface, 15-first inner conical surface, 2-conical top block, 21-supporting flange, 3-shell expanding inner wedge, 30-cone, 31-outer conical surface, 4-anchor rod, 40-grout outlet, 41-connecting sleeve, 42-screw rod, 5-extrusion head, 6-anchor rod body, 7-backing plate, 8-driving nut, 80-anti-seismic box, 81-yielding component and 9-anchor hole.
Detailed Description
The present invention will now be described in more detail with reference to the accompanying drawings, in which the description of the invention is given by way of illustration and not of limitation. The various embodiments may be combined with each other to form other embodiments not shown in the following description.
The shell expansion anchor rod for soft rock provided by the invention is simple in structure, low in production cost, good in anchoring performance and suitable for mechanical automation operation, so that the construction efficiency is obviously improved.
The anchoring head structure of the shell expansion anchor rod for soft rock is shown in figures 1 and 2 and comprises an expansion shell, an expansion shell inner wedge 3 and a conical top block 2, wherein the expansion shell inner wedge 3 and the conical top block 2 are arranged at two ends of the expansion shell, the materials of all components adopt alloy steel, cast iron and other materials with certain strength, the expansion shell inner wedge 3 is movably embedded into the top of the expansion shell, the conical top block 2 is movably embedded into the bottom of the expansion shell, the anchor rod 4 comprises an anchor rod body 6, one end of the anchor rod body 6 is fixedly provided with a screw rod 42 through a connecting sleeve 41, the screw rod 42 is in threaded transmission connection with the expansion shell inner wedge 3, and the top of the connecting sleeve 41 is embedded into the conical top block 2 and compresses a;
the shell expanding of the shell expanding anchor rod for soft rock comprises shell expanding connecting parts 11 and shell expanding pieces 1 which are integrally formed, wherein two groups of the shell expanding pieces 1 are respectively arranged on two sides of the shell expanding, the shell expanding pieces 1 in the same group are annularly and uniformly arranged on the shell expanding connecting parts 11, the number of the shell expanding pieces 1 in each group is more than two, the shapes of the shell expanding pieces 1 in the same group are the same, strip-shaped grooves are formed between the adjacent shell expanding pieces 1, so that the shell expanding pieces 1 can be gradually expanded outwards, a first inner conical surface 15, an inner annular surface 14 and a second inner conical surface 13 are formed at the upper part and the lower part of the inner side of the shell expanding, and the first inner conical surface 15 and the second inner conical surface 13 are respectively matched with the shapes of a shell expanding inner wedge 3 and a conical ejector block 2; in the embodiment, the number of the shell expansion pieces 1 is four, so that the contact area between the shell expansion pieces 1 and the wall of the surrounding rock is effectively increased, the outer sides of the shell expansion pieces 1 are provided with the continuously arranged sawteeth 12, the friction force between the shell expansion pieces and the wall of the surrounding rock is effectively increased, and the anchoring performance of the shell expansion pieces is improved;
the shell expansion inner wedge 3 of the shell expansion anchor rod for soft rock is of a conical nut structure and comprises a cone 30, wherein a through hole with internal threads is arranged in the cone 30, an external conical surface 31 of the cone 30 is in sliding contact with a first internal conical surface 15 of the shell expansion, a through hole is arranged in a conical ejection block 2, an annular supporting flange 21 matched with the top of a connecting sleeve 41 is arranged above the through hole, the supporting flange 21 has a function of limiting the connecting sleeve 41 before fracture, and mainly plays a role in supporting and clamping the shell expansion in the inner part after fracture, and the external conical surface 31 of the conical ejection block 2 is in sliding contact with a second internal conical surface 13 of the shell expansion;
further, shell connecting portion 11 that rises also can be in external force surpass its intensity limit from the fracture of bar fluting department, then make shell piece 1 that rises outwards expand more fully to better adaptation soft rock stratum or even different operating modes expand the range of application, can understand: according to the application scene and the processing and manufacturing requirements, the expanding shell can also be designed into various types of split structures, such as: 1) the two groups of shell expansion pieces 1 are all nested in the same shell expansion connecting part 11; 2) the same shell expansion connecting part 11 and one of the two shell expansion pieces 1 are integrally formed; 3) a group of shell expansion sheets 1 and a shell expansion connecting part 11 are nested after being integrally formed.
As shown in fig. 3 and 4, the top of the connecting sleeve 41 can be provided with an independent extrusion head 5, the top of the extrusion head 5 is movably contacted with the supporting flange 21 above the through hole of the conical top block 2, and has the advantages of easy standardized manufacture and low cost, and the other end of the anchor rod body 6 is provided with a backing plate 7 and a driving nut 8 to form a set of soft rock shell-expanding anchor rod fixed in the anchor hole 9;
by rotating the driving nut 8, the anchor rod body 6 rotates to drive the connecting sleeve 41 and the screw rod 42 to rotate, the top of the connecting sleeve 41 or the extrusion head 5 presses the supporting flange 21 of the conical top block 2 to apply pressing force inwards to the expanding shell, the screw rod 42 drives the inner wedge 3 of the expanding shell to move towards the inner side of the expanding shell piece 1 and apply pressing force outwards to the expanding shell, the expanding shell deforms under the action of force at the upper end and the lower end, the sawteeth 12 of the upper group of expanding shell piece 1 and the lower group of expanding shell piece 1 cling to the wall of the surrounding rock, the conical top block 2 is clamped in the lower group of expanding shell piece 1 due to the fact that the supporting flange 21 of the conical top block 2 is broken because of exceeding the strength limit by continuing to rotate, and therefore structural stability is kept after the expanding shell tightly clings to the surrounding rock, and prestress application action and rock stratum compression effect on the anchor;
in this embodiment, set up driving nut 8 to blind nut, set up the external screw thread on the stock body 6, set up the internal thread on adapter sleeve 41, stock body 6 is fastening installation and constitutes a body structure with driving nut 8 and adapter sleeve 41, under the drive of blind nut, rises shell inner wedge 3 and toper kicking block 2, stock body 6 and is the relative motion, promptly: the driving nut 8 is rotated, the inner wedge 3 of the expanding shell moves towards the inside of the expanding shell (outside the anchor hole 9) along the screw rod 42, the conical jacking block 2 and the anchor rod body 6 move towards the inside of the anchor hole 9, and the anchor rod body 6 is ensured not to be exposed;
further, as shown in fig. 5, the anchor rod body 6 may be provided as a hollow anchor rod 4, and a grout outlet 40 is provided on the connecting sleeve 41, so that grouting of the anchor rod 4 is facilitated, and thus the anchoring performance is enhanced.
Further, as shown in fig. 6, an anti-seismic box 80 is arranged between the driving nut 8 and the backing plate 7 to form a prestressed anti-seismic anchor rod which is suitable for being used in projects with anti-seismic requirements, such as earthquake regions, military projects and the like;
further, as shown in fig. 7, a yielding component 81 is arranged at the end of the anchor rod body 6 to form a yielding anchor rod for soft rock capable of being prestressed;
further, as shown in fig. 8, an anti-seismic box 80 is arranged between the driving nut 8 of the yielding anchor rod and the backing plate 7, so that the prestressed anti-seismic yielding anchor rod is formed, and the application range is further expanded.
Compared with the existing shell expansion anchor rod, the extremely soft rock shell expansion anchor rod provided by the invention has the advantages that the number of shell expansion structural components is small, the design is simpler, the standardized production is easy to realize, the cost is low, the assembly is convenient, the sawtooth 12 structure outside the expansion shell has good adhesive force with the wall of a surrounding rock hole, particularly, the expansion shell inner wedge 3, the conical top block 2 and the two groups of shell expansion pieces 1 positioned above and below the shell expansion connecting part 11 form an expansion structure attached to the wall of the surrounding rock hole, and the group of shell expansion pieces 1 positioned below has a barb effect embedded into a soft rock stratum, so that the structural stability can be kept after the shell expansion connecting part 11 is broken, and the excellent anchoring effect is achieved on the soft rock stratum.
As shown in fig. 9 and 10, the construction process of the present invention is divided into the following steps: 1) drilling: drilling an anchor hole 9 in the rock body through a drill bit; 2) assembly installation: a shell-expanding anchor rod assembly which is assembled in advance in the anchor hole 9 is used for enabling the backing plate 7 to be tightly attached to the rock wall at the mouth of the anchor hole 9; 3) anchoring: the driving nut 8 is rotated, the anchor rod body 6 rotates to drive the connecting sleeve 41 and the screw rod 42 to rotate, so that the conical jacking block 2 moves into the anchor hole 9 to apply pretightening force, and the inner wedge 3 of the expanding shell moves towards the outer side of the anchor hole 9, thereby realizing the close attachment and fixation of the expanding shell on the anchor hole 9 and applying prestress to a rock stratum; the anchoring step can be specifically divided into the following sub-steps:
a) an initial stage: rotating the anchor rod 4 to drive the connecting sleeve 41 or the extrusion head 5 to extrude the conical top block 2 inwards, so that the conical top block 2 applies pretightening force to the inside of the expanding shell, and the screw rod 42 rotates to enable the inner wedge 3 of the expanding shell to slide towards the inside of the expanding shell, so that the expanding shell pieces 1 are pushed to deform outwards to be attached to the wall of the surrounding rock, and even the end parts of one group of the outer expanding shell pieces 1 are inserted into the wall of the surrounding rock in a barb manner, so that the expansion shell is fixed;
b) an intermediate stage: continuing to rotate the anchor rod 4, and when the torque exceeds a certain value and the acting force of the connecting sleeve 41 or the extrusion head 5 exceeds the strength limit of the supporting flange 21 of the conical ejector block 2, breaking the supporting flange 21 to make the inner space out;
c) and (5) finishing: continue to rotate stock 4, screw rod 42 will drive 6 upper ends of the stock body through adapter sleeve 41 and move up, make 4 elastic extension of stock, to rising shell inner wedge 3, toper kicking block 2 and rising the shell and exert the axial pretightning force, at this moment, the axial pretightning force passes through the stock body 6, drive nut 8 and backing plate 7 transmit for 9 mouth cliff boards in anchor eye, rise the shell inside then by rising shell inner wedge 3, toper kicking block 2, screw rod 42 realizes supporting, it then passes through the chucking of sawtooth 12 structure on the country rock pore wall to rise the shell outside, thereby make and rise the shell stock and carry out effectual prestressing force to the country rock and apply and form soft rock compression area.
In the existing construction method of the expanding shell anchor rod, such as the patent of application No. CN201910265475.6 and the patent of application No. CN201510711711.4, the anchor rod body needs to move towards the outside of the anchor hole in the construction process, so that the outer end of the anchor rod body extends out of the rock mass outside the anchor hole after the operation is finished. Based on factors such as safety and technological requirements, redundant anchor rod bodies at exposed ends need to be cut off, and at present, the cutting step depends on manual operation, so that the operation steps are increased, the construction efficiency is reduced, and the problems of increased engineering cost, material waste and the like are caused.
According to the construction method of the expansion shell anchor rod for the soft rock, the expansion shell is expanded to the rock wall by driving the expansion shell inner wedge 3 and the conical jacking block 2 to move oppositely along the screw rod of the anchor rod body 6, and the anchor rod body 6 stays in the anchor hole 9 all the time in the construction process, so that the construction method does not need a cutting step, is simple in construction step, is convenient to realize mechanical automatic operation, and greatly improves the working efficiency.
The above embodiments are only preferred embodiments of the present invention, and the protection scope of the present invention is not limited thereby, and any insubstantial changes and substitutions made by those skilled in the art based on the present invention are within the protection scope of the present invention.

Claims (12)

1. The utility model provides a soft rock is with rising shell stock, is including rising shell, stock, its characterized in that: an inner expanding shell wedge and a conical top block are respectively arranged at two ends of the expanding shell, and the inner expanding shell wedge is in sliding contact with the top of the expanding shell and the conical top block is in sliding contact with the bottom of the expanding shell; the anchor rod comprises an anchor rod body, one end of the anchor rod body is fixedly provided with a screw rod through a connecting sleeve, the screw rod is in transmission connection with the inner wedge of the expanding shell through threads, and the top of the connecting sleeve is embedded into the conical ejecting block and tightly presses the supporting flange of the conical ejecting block; and rotating the anchor rod to drive the inner wedge of the expansion shell and the conical ejection block to move towards the inside of the expansion shell until the supporting flange of the conical ejection block is broken, so that the expansion shell piece deforms outwards and expands to the wall of the surrounding rock hole to apply prestress to the rock mass.
2. A soft rock shell-expanding anchor rod as claimed in claim 1, wherein: the shell that rises includes integrated into one piece's shell connecting portion that rises and set up two sets of shell pieces that rise in shell connecting portion both sides respectively, and every group rises shell piece circumference and sets up on rising shell connecting portion, rises the shell inboard and is formed with first inner conical surface, interior anchor ring and second inner conical surface from top to bottom, and wherein first inner conical surface, second inner conical surface respectively with rise the shape looks adaptation of shell inner wedge, toper kicking block.
3. A soft rock shell-expanding anchor rod as claimed in claim 2, wherein: the conical ejecting block is internally provided with a through hole, an annular supporting flange matched with the top of the connecting sleeve is arranged above the through hole, and the outer conical surface of the conical ejecting block is in sliding contact with the second inner conical surface of the expanding shell.
4. A soft rock shell-expanding anchor rod as claimed in claim 2 or 3, wherein: the inner wedge of the expansion shell is of a cone nut structure and comprises a cone, a through hole with internal threads is formed in the cone, and the outer conical surface of the cone is in sliding contact with the first inner conical surface of the expansion shell.
5. A soft rock shell-expanding anchor rod as claimed in claim 1, wherein: the shell that rises adopts split type structure, two sets of shell connecting portions that rise are nested in same shell connecting portion that rises, or same shell connecting portion that rise and a set of integrated into one piece in two sets of shell pieces that rise, or a set of shell piece that rises and the nested setting behind the shell connecting portion integrated into one piece that rises.
6. A shell-expanding anchor for soft rock as claimed in claim 1, 2 or 5, wherein: the outer side of the shell expansion sheet is provided with continuously arranged sawteeth.
7. A soft rock shell-expanding anchor rod as claimed in claim 6, wherein: the anchor rod body end portion is provided with a base plate and a driving nut, two ends of the anchor rod body are fixedly installed with the driving nut and the connecting sleeve respectively, and the driving nut is rotated to enable the anchor rod body to rotate and extrude the conical jacking block through the connecting sleeve.
8. A soft rock shell-expanding anchor rod as claimed in claim 7, wherein: the top of the connecting sleeve is provided with an independent extrusion head.
9. A soft rock shell-expanding anchor rod as claimed in claim 8, wherein: the anchor rod body is a hollow anchor rod, and the connecting sleeve is provided with a grout outlet.
10. A soft rock shell-expanding anchor rod as claimed in claim 9, wherein: an anti-seismic box is arranged between the driving nut and the base plate, and a yielding component is arranged at the end part of the anchor rod body.
11. A construction method of a shell expansion anchor rod for soft rock is characterized by comprising the following steps:
s1 drilling: drilling an anchor hole in the rock mass through a drill bit;
and (3) mounting the S2 component: inserting a pre-assembled shell expansion anchor rod component into the anchor hole to enable the backing plate to be tightly attached to the rock wall of the anchor hole opening;
s3 anchoring: the driving nut is rotated, the anchor rod body rotates to drive the connecting sleeve and the screw rod to rotate, so that the conical jacking block moves into the anchor hole to apply pretightening force, and the expansion shell inner wedge moves towards the outer side of the anchor hole, and the expansion shell is tightly attached to and fixed on the anchor hole and applies prestress to a rock stratum.
12. The construction method of a soft rock expansion anchor rod according to claim 11, wherein the step S3 includes the following substeps:
initial stage of S31: rotating the anchor rod to drive the connecting sleeve to extrude the conical ejecting block inwards to apply pretightening force to the inner part of the expansion shell, and rotating the screw rod to enable the inner wedge of the expansion shell to slide towards the expansion shell, so that the expansion shell pieces are pushed to deform outwards to be attached to the wall of the surrounding rock hole, and even the end parts of a group of the expansion shell pieces at the outer side are inserted into the wall of the surrounding rock hole in a barb manner, so that the expansion shell fixation is completed;
s32 intermediate stage: the anchor rod is continuously rotated, when the torque exceeds a certain value and the acting force of the connecting sleeve exceeds the strength limit of the supporting flange of the conical top block, the supporting flange is broken, and an internal space is made;
s33 end stage: and continuing to rotate the anchor rod, driving the upper end of the anchor rod body to move upwards through the connecting sleeve by the screw rod, elastically extending the anchor rod, and applying axial pretightening force to the inner wedge, the conical jacking block and the expanding shell of the expanding shell, wherein at the moment, the axial pretightening force is transmitted to the rock wall of the anchor hole through the anchor rod body, the driving nut and the base plate, so that effective prestress application action is carried out on the surrounding rock.
CN202010412166.XA 2020-05-15 2020-05-15 Shell expansion anchor rod for soft rock and construction method thereof Pending CN111594241A (en)

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Cited By (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN112593987A (en) * 2020-12-24 2021-04-02 中铁二院工程集团有限责任公司 Bonding anchoring type first-anchoring yielding hollow anchor rod and anchoring method
CN113090305A (en) * 2021-04-30 2021-07-09 中煤科工开采研究院有限公司 Anchor bolt support construction method
CN114320416A (en) * 2021-12-29 2022-04-12 西安建筑科技大学 Expansion shell type yielding anchor rod and use method thereof
CN114607428A (en) * 2022-03-08 2022-06-10 长江水利委员会长江科学院 Inner anchor type telescopic anchor rod for soft rock reinforcement and application method

Citations (7)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
GB2022756A (en) * 1978-06-05 1979-12-19 Williams C I Mine Bolt and Method of Installing a Mine Bolt in Rock Formation
US5033910A (en) * 1990-03-19 1991-07-23 The Eastern Company Mechanical expansion anchor shell
US20020094240A1 (en) * 2001-01-12 2002-07-18 Cook James D. Expansion shell assembly
CN1544798A (en) * 2003-11-11 2004-11-10 吴德兴 Shell expansion type rock bolt
WO2007140159A1 (en) * 2006-05-30 2007-12-06 Jennmar Corporation Tensionable bolt with hanger
EP3396105A1 (en) * 2017-04-24 2018-10-31 Bochumer Eisenhütte Heintzmann GmbH&Co. Kg Expansion-shell bolt with lost drill bit
CN212318049U (en) * 2020-05-15 2021-01-08 浙江聚能岩土锚固研究有限公司 Shell expansion anchor rod for soft rock

Patent Citations (7)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
GB2022756A (en) * 1978-06-05 1979-12-19 Williams C I Mine Bolt and Method of Installing a Mine Bolt in Rock Formation
US5033910A (en) * 1990-03-19 1991-07-23 The Eastern Company Mechanical expansion anchor shell
US20020094240A1 (en) * 2001-01-12 2002-07-18 Cook James D. Expansion shell assembly
CN1544798A (en) * 2003-11-11 2004-11-10 吴德兴 Shell expansion type rock bolt
WO2007140159A1 (en) * 2006-05-30 2007-12-06 Jennmar Corporation Tensionable bolt with hanger
EP3396105A1 (en) * 2017-04-24 2018-10-31 Bochumer Eisenhütte Heintzmann GmbH&Co. Kg Expansion-shell bolt with lost drill bit
CN212318049U (en) * 2020-05-15 2021-01-08 浙江聚能岩土锚固研究有限公司 Shell expansion anchor rod for soft rock

Cited By (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN112593987A (en) * 2020-12-24 2021-04-02 中铁二院工程集团有限责任公司 Bonding anchoring type first-anchoring yielding hollow anchor rod and anchoring method
CN113090305A (en) * 2021-04-30 2021-07-09 中煤科工开采研究院有限公司 Anchor bolt support construction method
CN113090305B (en) * 2021-04-30 2023-12-29 中煤科工开采研究院有限公司 Anchor bolt support construction method
CN114320416A (en) * 2021-12-29 2022-04-12 西安建筑科技大学 Expansion shell type yielding anchor rod and use method thereof
CN114607428A (en) * 2022-03-08 2022-06-10 长江水利委员会长江科学院 Inner anchor type telescopic anchor rod for soft rock reinforcement and application method

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