CN210031791U - Anchor cable hole bottom reverse traction device - Google Patents
Anchor cable hole bottom reverse traction device Download PDFInfo
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- CN210031791U CN210031791U CN201920453579.5U CN201920453579U CN210031791U CN 210031791 U CN210031791 U CN 210031791U CN 201920453579 U CN201920453579 U CN 201920453579U CN 210031791 U CN210031791 U CN 210031791U
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Abstract
The utility model relates to a reverse tractive device in anchor rope hole bottom. The device comprises a base, a barb mechanism and a traction mechanism, wherein the base is limited in an anchor cable hole through the barb mechanism, one end of a traction rope of the traction mechanism extends out of the anchor cable hole and is connected with an anchor cable, and the other end of the traction rope is connected with external power. The invention better solves a series of problems of difficult anchor cable installation, rotation and distortion of the anchor cable body in a drill hole, serious prestress loss, low anchor cable construction efficiency, difficult reinforcement quality meeting engineering requirements and the like in the traditional orifice pushing installation method in the current anchor cable construction process. The fixed pulley at the bottom of the hole is utilized, the installation of the anchor cable is changed from pushing at the tail part to traction at the head part by a reverse traction method, the bending and twisting phenomena and the installation difficulty are avoided, and the construction efficiency of the anchor cable is improved; after the anchor cable is installed, the anchor cable body is in a straight state in the drilled hole, the prestress loss in the anchor cable stretching process is effectively reduced, and the anchoring quality of the anchor cable is guaranteed.
Description
Technical Field
The invention relates to the technical field of civil engineering, in particular to a reverse traction device for a hole bottom of an anchor cable.
Background
Since the anchor cable technology is introduced into China in the 60 th of the 20 th century, the anchor cable technology is widely applied to various civil engineering fields, and the achievement of the anchor cable technology in the aspects of water conservancy and hydropower is more remarkable. At present, anchor cables become important technology for supporting and reinforcing dam foundations, side slopes and underground caverns in hydraulic and hydroelectric engineering. The anchor cable is generally formed by bundling high-strength steel strands in parallel, the high-strength steel strands are pushed into a rock soil drilled hole which is completed in advance in a manual mode, then the root of the anchor cable is grouted and fixed, and then the exposed end of the slope surface is tensioned by a jack to apply reverse pressure to a reinforced rock mass.
The anchor cable construction is generally carried out according to the following construction procedures: measuring and positioning → pore-creating → anchor cable manufacturing → anchor cable installation → anchor cable grouting → anchor cable graded tensioning → anchor cable locking. The anchor cable installation means that after the anchor cable is manufactured, the anchor cable body is pushed into a pre-finished drilled hole through a hole opening in a manual mode.
However, in view of the anchor cable construction under complex conditions such as high steep slope, narrow cavern, the actual work progress, there is following problem when the anchor cable adopts traditional drill way propelling movement mounting method:
1. the anchor cable body is flexible and difficult to push:
the anchor cable is composed of steel strand and other parts, belongs to a tension member in engineering, has a linear flexible body as mechanical characteristics, and has more obvious flexible characteristics due to the long length (the length is generally 30-50 m). When the traditional installation is carried out by pushing from the hole opening to the hole, the application point of the pushing force can be and only can be the cable body part outside the hole opening. This method is equivalent to threading a soft noodle through a straw. Because the anchor cable is a linear flexible body and friction exists between the cable body and the wall of the drilled hole, the cable body is very easy to buckle into an S shape in the process of transmitting the axial thrust of the hole opening inwards along the flexible cable body, and the on-way friction of the cable body is increased, so that the pushing difficulty is caused.
Especially, when the inclined anchor cable is installed, the action of the friction force of the hole wall and the action of the weight of the anchor cable are overcome, and the traditional orifice pushing installation method is more difficult.
2. The anchor cable body is easy to twist and has serious prestress loss
When the traditional orifice pushing and mounting method is adopted, the anchor cable body can be twisted along the axial direction in the pushing process, so that the anchor cable is twisted, the twisting and plugging of the exhaust pipe and the grouting pipe can be caused, the later grouting effect is influenced, or the anchor cable needs to be pulled out to be repaired and mounted again, and even the anchor cable is scrapped.
Axial torsion of the anchor cable body can not only cause the distortion of the exhaust pipe and the grouting pipe, but also cause great adverse effect on later-stage anchor cable tensioning. Because the anchor cable body is in a twisted state, the friction force of the anchor cable stranded wire in the tensioning process is increased, and the anchoring force is lost along the way, so that the prestress loss of the anchor cable is caused, and the anchoring effect of the anchor cable is finally influenced.
Disclosure of Invention
In order to solve the problems, the invention provides a reverse traction device for the hole bottom of an anchor cable. .
The technical scheme adopted by the invention is as follows: the utility model provides an anchor rope hole bottom reverse tractive device which characterized in that: the base is limited in the anchor cable hole through the barb mechanism, one end of a traction rope of the traction mechanism extends out of the anchor cable hole and is connected with the anchor cable, and the other end of the traction rope is connected with external power.
Preferably, the base is cylindrical, and the base is provided with at least one barb mechanism along the circumferential direction.
Further, the base comprises two half bases with the same structure, and the two half bases are fixedly connected through bolts.
Furthermore, each half base is provided with a barb mechanism.
Preferably, the barb device comprises a steel pin and a spring, one end of the steel pin is hinged to the base, and the other end of the steel pin extends out of the base and inclines to one side of the anchor cable hole; one end of the spring is connected with the base, and the other end of the spring is connected with the steel pin.
Furthermore, the traction mechanism comprises a pulley arranged in the base, one end of the traction rope extends out of the anchor rope hole to be connected with the anchor rope, and the other end of the traction rope bypasses the pulley to be connected with external power.
The method for installing the anchor cable by adopting the reverse traction device at the hole bottom of the anchor cable comprises the following steps:
(1) drilling an anchor cable hole: confirming the position, the direction, the bore diameter and the bore depth of the anchor cable bore according to the requirements of a construction drawing, and performing anchor cable bore drilling construction;
(2) manufacturing an anchor cable;
(3) assembling an anchor cable hole bottom reverse traction device: firstly, a steel wire rope penetrates through a fixed pulley, and then the fixed pulley, a spring and a steel pin are arranged in a reserved groove of a base;
(4) and installing an anchor cable hole bottom reverse traction device: pushing the anchor cable hole bottom reverse traction device assembled in the step (3) to the bottom of the anchor cable hole, wherein the steel pin contracts under the action of the reverse pressure of the hole wall, and when the device is pushed to the anchor cable hole bottom reaming section, the steel pin expands under the action of a spring, so that the end part of the steel pin is clamped on a rock bed of the anchor cable hole bottom reaming section, and the whole device is clamped at the bottom of the anchor cable hole;
(5) and installing an anchor cable: one end of a steel wire rope is tied to the inner end head of the anchor cable, the other end of the steel wire rope is arranged at an orifice and is connected with external power, and under the action of the external power and a fixed pulley, the cable body of the anchor cable is pulled to the designed hole depth to complete the installation of the anchor cable;
(6) grouting and prestressed tensioning: and grouting after the installation of the anchor cable is finished, and stretching the anchor cable step by step after the slurry is solidified.
Preferably, in the step (1), during the anchor cable hole drilling construction, the anchor cable hole is drilled to the designed hole depth according to the designed hole diameter, and the anchor cable hole is drilled 20cm forward, and the hole is expanded by 10cm at the tail end.
The beneficial effects obtained by the invention are as follows: the anchor cable pushing and installing method well solves a series of problems that in the current anchor cable construction process, the traditional orifice pushing and installing method is difficult to install the anchor cable, an anchor cable body rotates and twists in a drill hole, the prestress loss is serious, the anchor cable construction efficiency is low, the reinforcement quality is difficult to meet engineering requirements, and the like. Compared with the traditional installation method, the invention has the following outstanding advantages:
(1) the fixed pulley at the bottom of the hole is utilized, the 'pushing' of the tail part of the anchor cable installation is changed into the 'traction' of the head part by a reverse traction method, the bending and twisting phenomena and the installation difficulty are avoided, and the anchor cable construction efficiency is improved.
The mechanical property of the anchor cable is a linear flexible body, and when the traditional orifice pushing installation method is adopted, the force transmission effect of the thrust along the axial direction of the anchor cable is obviously reduced. The invention has the advantages that the tensile force is applied to the steel wire rope at the orifice, the steel wire rope is converted into the reverse tensile force to the anchor cable body under the action of the hole bottom fixed pulley, the anchor cable body is finally pulled to the designed hole depth, the whole length of the anchor cable body is in a tensile state in the installation process, and the characteristic that the linear flexible body has good force transmission effect along the axial tensile force is well utilized. Therefore, the method greatly reduces the installation difficulty of the anchor cable, improves the one-time installation success rate and the construction efficiency of the anchor cable, saves the construction period, and has great significance for slope reinforcement emergency work.
(2) After the anchor cable is installed, the anchor cable body is in a straight state in the drilled hole, the prestress loss in the anchor cable stretching process is effectively reduced, and the anchoring quality of the anchor cable is guaranteed.
When the traditional anchor cable orifice pushing and mounting method is adopted, the anchor cable body can be buckled and twisted along the axial direction in the pushing process, so that the friction force between the anchor cable body and the hole wall in the later anchor cable stretching process is increased, and the anchor cable prestress loss is caused. Because the invention adopts the installation method of reverse traction of the hole bottom, the whole length of the anchor cable body is in a tensioned state, and the cable body is in a straight state under the action of the tension. Because the anchor cable body is in a straight state, the on-way loss of the anchoring force is greatly reduced in the later tensioning process, and the prestress of the anchor cable is ensured to reach a design rated value. Therefore, the invention reduces the prestress loss of the anchor cable and ensures the reinforcing effect of the anchor cable and the construction quality of engineering.
Drawings
FIG. 1 is a schematic structural view of the present invention;
FIG. 2 is a schematic structural diagram of a base half;
FIG. 3 is a schematic view of anchor cable installation;
reference numerals: 100. the anchor cable hole bottom reverse traction device comprises an anchor cable hole bottom reverse traction device body 1, a base, 11, a fixed pulley pre-assembly groove, 12, a fixed pulley rotating shaft pre-assembly groove, 13, a steel pin pre-assembly groove, 14, a spring pre-assembly groove, 15, a bolt hole, 2, a fixed pulley, 21, a fixed pulley rotating shaft, 22, a traction rope, 3, a steel pin, 4, a spring, 200, an anchor cable hole, 201, an anchor cable hole expanding section and 300.
Detailed Description
The invention will be further described with reference to the following drawings and specific embodiments.
As shown in fig. 1-3, the anchor cable hole bottom reverse traction device of the present invention includes a base 1 disposed at the bottom of an anchor cable hole 200, a barb mechanism and a traction mechanism, wherein the barb mechanism is disposed on the base 1 and is used for limiting the base 1 at the bottom of the anchor cable hole 200, and simultaneously ensuring that the base 1 can be smoothly pushed to the hole bottom from an orifice of the anchor cable hole 200; the traction mechanism is installed in the base 1, one end of a traction rope 22 of the traction mechanism extends out of the anchor rope hole 200 and is connected with the anchor rope 300, the other end of the traction rope is connected with external power, the external power is applied to the traction rope 22, and after the direction is changed through the traction mechanism, the anchor rope 300 is drawn to the deep part of the design hole from the orifice of the anchor rope hole 200.
The base 1 is cylindrical, and the base 1 is provided with at least one barb mechanism along the circumferential direction, and in this embodiment, two barb mechanisms are symmetrically provided on the base 1 along the circumferential direction.
In the embodiment, the barb device comprises a steel pin 3 and a spring 4, one end of the steel pin 3 is hinged to the base 1, and the other end of the steel pin extends out of the base 1 and inclines to one side of the anchor cable hole 200; one end of the spring 4 is connected with the base 1, and the other end is connected with the steel pin 3. In the process of pushing the anchor cable hole bottom reverse traction device 100 from the anchor cable hole 200 hole opening to the hole bottom, the steel pin 3 is pushed by the anchor cable hole 200 hole wall and is folded towards one side of the base 1, and the spring 4 is compressed; after the anchor cable hole bottom reverse traction device 100 is pushed to the hole bottom, the steel pin 3 is opened at the anchor cable hole reaming section 201, the steel pin 3 is abutted against rocks in the anchor cable hole 200, and the whole anchor cable hole bottom reverse traction device 100 is firmly limited at the hole bottom of the anchor cable hole 200.
In this embodiment, the traction mechanism includes a pulley 2 (which may be in the form of a pulley block and may be disposable in this embodiment, and only one fixed pulley is used to change the stress direction because the whole device is disposable and not recyclable), and one end of the traction rope 22 (which is a steel wire rope) extends out of the anchor rope hole 200 to be connected to the anchor rope 300, and the other end of the traction rope bypasses the fixed pulley 2 to be connected to external power.
The base 1 is the foundation of the whole device, and is provided with a fixed pulley pre-assembly groove 11, a fixed pulley rotating shaft pre-assembly groove 12, a steel pin pre-assembly groove 13 and a spring pre-assembly groove 14, wherein the fixed pulley 2, the fixed pulley rotating shaft 21, the steel pin 3 and the spring 4 are respectively arranged in the corresponding pre-assembly grooves. In this embodiment, the base 1 is made of cast iron and is composed of two symmetrical blocks, and the single block is semi-cylindrical, 130mm high and 150mm diameter (slightly smaller than the drilled hole). The middle part of the base 1 is provided with a fixed pulley preformed groove 11 with the size of 40mm in width, 110mm in height and 45mm in depth, and two sides are provided with fixed pulley rotating shaft preformed grooves 12 with the diameter of 8mm and the depth of 10mm, so that the fixed pulley rotating shaft 21 can be conveniently installed; the two sides of the steel pin are provided with steel pin preformed grooves 13 with the maximum width of 20mm, the maximum height of 50mm and the depth of 10mm, and the bottom of each steel pin preformed groove is provided with a preformed hole with the diameter of 8mm and the depth of 5mm, so that the steel pin rotating shaft can be conveniently installed; a spring preformed groove 14 with the diameter of 14mm multiplied by the depth of 33mm is arranged on the inner side of the steel pin preformed groove 13; bolt holes 15 with the diameter of 6.5mm are arranged on the periphery of the base 1. The bolt 15 can combine the bases of the two half blocks into a complete cylindrical base 1 through the bolt hole 15 and restrain the fixed pulley 2, the steel pin 3 and the spring 4 which are arranged in the reserved groove.
In this embodiment, the spring 4 is made of alloy spring steel, and has an outer diameter of 14mm and a length of 40 mm.
In this embodiment, the steel pin 3 is made of carbon steel, and has a length of 45mm, a width of 10mm, and a height of 20mm, and has a semicircular end with a diameter of 10mm, and two rotating shafts with a diameter of 7.5mm, and a height of 5mm are disposed on two sides.
In this embodiment, the fixed pulley 2 is made of carbon steel, and has a diameter of 84mm × a width of 30mm, a wheel groove having a width of 20mm × a depth of 5mm is formed in the middle, and a rotating shaft having a diameter of 7.8mm × a height of 10mm is formed in the center of both sides of the fixed pulley.
In this embodiment, the steel wire rope is made of a common steel wire, the diameter of the steel wire rope is not less than 4mm, and the length of the steel wire rope is determined according to the hole depth of the anchor cable, which is generally (2 times of the hole depth of the anchor cable plus the external operation length of the orifice).
In this embodiment, the bolt is made of carbon steel and has a diameter of 6.5 mm.
The dimensions of the parts listed above are the dimensions used in a certain project, and the actual dimensions used can be adjusted according to specific project requirements.
During assembly, firstly, the steel wire rope 22 penetrates through the fixed pulley 2, secondly, the fixed pulley 2, the spring 4 and the steel pin 3 are placed in a corresponding preformed groove of the base 1, then, the other base is spliced, and finally, bolts are installed in the four bolt holes 15 on the periphery of the base 1 for fastening.
The method for installing the anchor cable by adopting the reverse traction device at the hole bottom of the anchor cable comprises the following steps:
(1) drilling an anchor cable hole: before the construction of the anchor cable, confirming the position, the direction, the aperture and the hole depth of the anchor cable drilling hole according to the requirements of a construction drawing, drilling to the designed hole depth according to the designed aperture (165 mm is taken as an example in the invention) and continuously drilling for 20cm forwards, wherein the aperture is expanded to 180mm by a reaming bit at the tail end of 10 cm;
(2) and manufacturing an anchor cable: bundling the components such as the grouting pipe, the steel strand, the isolation bracket and the like into a bundle, and filling the bundle into the corrugated pipe after the bundling is finished;
(3) assembling an anchor cable hole bottom reverse traction device: firstly, a steel wire rope penetrates through a fixed pulley, then the fixed pulley, a spring and a steel pin are placed in a reserved groove of a base, then the other base is spliced, and finally bolts are installed in four bolt holes on the periphery of the base for fastening to complete the assembly of the anchor cable hole bottom reverse traction device;
(4) and installing an anchor cable hole bottom reverse traction device: pushing the anchor cable hole bottom reverse traction device assembled in the step (3) to the bottom of an anchor cable hole by using a drill rod, wherein the steel pin shrinks under the action of reverse pressure of the hole wall (the expansion width is the same as the designed diameter of the drilled hole), and when the device is pushed to an anchor cable hole bottom reaming section, the steel pin expands under the action of a spring, so that the end part of the steel pin is clamped on a rock platform of the anchor cable hole bottom reaming section, and further the whole device is clamped at the bottom of the anchor cable hole, and the installation of the anchor cable hole bottom reverse traction device is completed;
(5) and installing an anchor cable: one end of a steel wire rope is tied to the inner end head of the anchor rope, the other end of the steel wire rope is arranged at an orifice and is connected with external power (human or mechanical), and under the action of the external power and a fixed pulley, the cable body of the anchor rope is pulled to the designed hole depth to complete the installation of the anchor rope;
(6) grouting and prestressed tensioning: and grouting after the installation of the anchor cable is finished, and stretching the anchor cable step by step after the slurry is solidified.
The foregoing shows and describes the general principles and principal structural features of the present invention. The present invention is not limited to the above examples, and various changes and modifications may be made without departing from the spirit and scope of the invention, which fall within the scope of the claimed invention. The scope of the invention is defined by the appended claims and equivalents thereof.
Claims (6)
1. The utility model provides an anchor rope hole bottom reverse tractive device which characterized in that: including setting up base (1) in anchor rope hole (200) bottom, setting barb mechanism on base (1) and the drive mechanism of setting in the base, base (1) are restricted in anchor rope hole (200) through barb mechanism, drive mechanism's haulage rope (22) one end is stretched out anchor rope hole (200) and is connected with anchor rope (300) outward, and the other end is connected with outside power.
2. The cable bolt hole bottom reverse pulling device as claimed in claim 1, wherein: the base (1) is cylindrical, and the base (1) is provided with at least one barb mechanism along the circumferential direction.
3. The cable bolt hole bottom reverse pulling device as claimed in claim 2, wherein: the base (1) comprises two half bases with the same structure, and the two half bases are fixedly connected through bolts.
4. The cable bolt hole bottom reverse pulling device as claimed in claim 3, wherein: each semi-base is provided with a barb mechanism.
5. The anchor cable hole bottom reverse pulling device as claimed in any one of claims 1 to 4, wherein: the barb mechanism comprises a steel pin (3) and a spring (4), one end of the steel pin (3) is hinged to the base (1), and the other end of the steel pin (3) extends out of the base (1) and inclines to one side of the anchor cable hole (200); one end of the spring (4) is connected with the base (1), and the other end of the spring is connected with the steel pin (3).
6. The cable bolt hole bottom reverse pulling device as claimed in claim 5, wherein: the traction mechanism comprises a pulley (2) arranged in the base, one end of the traction rope (22) extends out of the anchor rope hole (200) and is connected with the anchor rope (300), and the other end of the traction rope bypasses the pulley (2) and is connected with external power.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201920453579.5U CN210031791U (en) | 2019-04-04 | 2019-04-04 | Anchor cable hole bottom reverse traction device |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201920453579.5U CN210031791U (en) | 2019-04-04 | 2019-04-04 | Anchor cable hole bottom reverse traction device |
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| CN210031791U true CN210031791U (en) | 2020-02-07 |
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| Application Number | Title | Priority Date | Filing Date |
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| CN201920453579.5U Active CN210031791U (en) | 2019-04-04 | 2019-04-04 | Anchor cable hole bottom reverse traction device |
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Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN109944241A (en) * | 2019-04-04 | 2019-06-28 | 长江勘测规划设计研究有限责任公司 | The reversed pulling device in anchor cable hole bottom and anchor cable installation method |
| CN114411775A (en) * | 2022-01-29 | 2022-04-29 | 重庆交通大学 | Anti-seismic anchor cable, anti-seismic response monitoring method and slope reinforcing method |
-
2019
- 2019-04-04 CN CN201920453579.5U patent/CN210031791U/en active Active
Cited By (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN109944241A (en) * | 2019-04-04 | 2019-06-28 | 长江勘测规划设计研究有限责任公司 | The reversed pulling device in anchor cable hole bottom and anchor cable installation method |
| CN109944241B (en) * | 2019-04-04 | 2023-11-10 | 长江勘测规划设计研究有限责任公司 | Anchor cable hole bottom reverse traction device and anchor cable installation method |
| CN114411775A (en) * | 2022-01-29 | 2022-04-29 | 重庆交通大学 | Anti-seismic anchor cable, anti-seismic response monitoring method and slope reinforcing method |
| CN114411775B (en) * | 2022-01-29 | 2024-05-14 | 重庆交通大学 | Anti-seismic anchor cable and slope reinforcement method |
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