CN114412527A - Multi-point grouting anchor rod and multi-point grouting process - Google Patents

Abstract

The invention discloses a multipoint grouting anchor rod, which comprises a hollow anchor rod body, a grouting multi-way joint and a pressure generator for outputting instantaneous high pressure into the hollow anchor rod body; a plurality of grouting side holes are axially formed in the rod body of the hollow anchor rod body, and sealing plugs matched with the grouting side holes are arranged on the grouting side holes; the invention also discloses a multipoint grouting process of the multipoint grouting anchor rod, which comprises the steps of installing the hollow anchor rod body, opening the sealing plug, performing multipoint grouting and the like; according to the invention, during grouting, the grouting efficiency is improved through multi-point grouting, the problem that grouting cannot be carried out when a grouting hole is blocked can be solved, and the problem that whether grouting is in place or not can not be judged because fragments are wrapped by slurry during grouting and a slurry return channel is blocked can be solved; meanwhile, the sealing plug is opened by instantaneous pressure, so that the condition that slurry cannot be injected into the end part of the hollow anchor rod body due to the fact that the sealing plug is automatically opened under grouting pressure when the end part of the hollow anchor rod body is grouted can be avoided.

Description

Multi-point grouting anchor rod and multi-point grouting process

Technical Field

The invention relates to the technical field of anchor rods, in particular to a multipoint grouting anchor rod and a multipoint grouting process.

Background

The grouting anchor rod is a new product developed according to the actual needs of tunnel engineering, slope treatment engineering, coal mine tunnel engineering and the like in China.

There are multiple operating modes during stock slip casting to coal mine and rock burst use as an example: when the anchor rod is used for anchoring a coal mine, the anchor rod is very easy to insert under the action of carbon powder generated in the drilling process. And because the coal mine soil layer/rock stratum hardness is low and large fragments can not be generated during drilling, the slurry can be easily repulped to the orifice of the anchor hole during grouting so as to observe whether the grouting is in place or not.

When the anchor is used for rock bump anchoring, the hardness of the rock bump is high, so that the drilling difficulty is high, a large amount of fragments are generated in the drilling (anchoring) process, and the fragments cannot be completely removed even if the subsequent hole cleaning is carried out; the problem that brings is that, the slip casting process, during the time of the mud return, the thick liquid wraps up the fragment and blocks up the mud return passageway (the space between stock and the anchor eye), directly leads to the stock can not the complete anchor, and the anchor effect is poor, and can not the mud return lead to unable judgement anchor borehole thick liquid slip casting condition. The method for solving the problem is commonly used in China, the water-cement ratio of normal slurry is increased to 0.35-0.45 to 0.6-0.65, sticky slurry is prevented from being wrapped by fragments by reducing the viscosity of the slurry, but the strength of the slurry is reduced even has no strength after the slurry is thinned, and finally the anchoring effect is linearly reduced and even becomes a 'decoration piece'.

In addition, the existing anchor rod is only provided with two grout outlet holes at the drill bit end, and once the anchor rod is inserted into the anchor hole or the grouting hole is blocked by fragments in the drilling process, the grouting effect is directly influenced.

Disclosure of Invention

The invention aims to overcome the defects of the prior art and provide a multipoint grouting anchor rod and a multipoint grouting process, the grouting efficiency is improved through multipoint grouting during grouting, the problem that grouting cannot be performed when a grouting hole is blocked and the problem that whether grouting is in place cannot be judged because fragments are wrapped by slurry to block a slurry return channel during grouting are solved, and the used slurry is the slurry meeting the standard specification and having the water-cement ratio of 0.35-0.4, so that the anchoring effect is effectively ensured; meanwhile, the sealing plug is opened by instantaneous pressure, so that the condition that slurry cannot be injected into the end part of the hollow anchor rod body due to the fact that the sealing plug is automatically opened under grouting pressure when the end part of the hollow anchor rod body is grouted can be avoided.

The purpose of the invention is realized by the following technical scheme:

the multi-point grouting anchor rod comprises a hollow anchor rod body, a grouting multi-way joint and a pressure generator for outputting instantaneous high pressure into the hollow anchor rod body;

the rod body of the hollow anchor rod body is provided with at least one grouting side hole along the axial direction, and the grouting side hole is provided with a sealing plug matched with the grouting side hole;

the pressure generator is connected with the hollow anchor rod body through a grouting multi-way joint.

Further, the pressure generator is an air cannon.

Further, the hollow anchor rod body is a hollow self-drilling anchor rod, a mechanical expanding shell type anchor rod or a common hollow anchor rod.

A multipoint grouting process of a multipoint grouting anchor rod comprises the following steps:

s10, mounting a hollow anchor rod body: positioning the hollow anchor rod body in the anchor hole to prepare for grouting;

s20, opening the sealing plug: outputting instantaneous high pressure into the hollow anchor rod body through a pressure generator to separate the sealing plug from the grouting side hole and enable the separated sealing plug to enter the anchor hole;

s30, multipoint grouting: and grouting into the hollow anchor rod body through the grouting multi-way connector, wherein the grout enters the anchor hole from the end part of the hollow anchor rod body and the plurality of grouting side holes.

Further, step S20 is preceded by the following steps:

s11, installing a pressure generator: the pressure generator is communicated with the interior of the hollow anchor rod body through the grouting multi-way connector, wherein the pressure generator is an air cannon.

Further, step S20 is preceded by the following steps:

s12, top grouting: and grouting into the hollow anchor rod body through the grouting multi-way connector, wherein the grout enters the anchor hole through the grouting hole at the end part of the hollow anchor rod body to anchor the end part of the hollow anchor rod body.

Further, the step S10 includes the following steps:

s101, self-drilling installation: drilling an anchor hole in the hollow anchor rod body through a drill bit at the end part, wherein when the drill bit is in place, the hollow anchor rod body is in place; wherein, the hollow anchor rod body is a hollow self-drilling anchor rod.

Further, the step S10 includes the following steps:

s102, inserting rod installation: drilling an anchor hole through a drilling tool, and withdrawing after drilling the anchor hole through the drilling tool; inserting the hollow anchor rod body into the anchor hole until the hollow anchor rod body is in place; wherein, the hollow anchor rod body is a mechanical expanding shell type anchor rod or a common hollow anchor rod.

The invention has the beneficial effects that:

according to the invention, during grouting, the grouting efficiency is improved through multi-point grouting, the problem that grouting cannot be carried out when a grouting hole is blocked and the problem that whether grouting is in place cannot be judged because the grouting liquid wraps fragments to block a grouting channel during grouting are solved, and the used grouting liquid is the grouting liquid which meets the standard specification and has a water-cement ratio of 0.35-0.4, so that the anchoring effect is effectively ensured; meanwhile, the sealing plug is opened by instantaneous pressure, so that the condition that slurry cannot be injected into the end part of the hollow anchor rod body due to the fact that the sealing plug is automatically opened under grouting pressure when the end part of the hollow anchor rod body is grouted can be avoided.

Drawings

Fig. 1 is a schematic overall structure diagram of a multipoint grouting anchor rod in an embodiment of the invention;

fig. 2 is a schematic structural diagram of the multipoint grouting anchor rod without a sealing plug in the embodiment of the invention;

FIG. 3 is a schematic structural view of a hollow anchor rod body according to embodiment 4 of the present invention;

in the figure, 1, a hollow anchor rod body; 2. grouting a multi-way joint; 3. a pressure generator; 4. grouting side holes; 5. a sealing plug; 6. an anchor eye; 7. and connecting the sleeve.

Detailed Description

The technical solutions of the present invention will be described clearly and completely with reference to the following embodiments, and it should be understood that the described embodiments are only a part of the embodiments of the present invention, and not all of the embodiments. All other embodiments, which can be obtained by a person skilled in the art without inventive effort based on the embodiments of the present invention, are within the scope of the present invention.

Referring to fig. 1 to 3, the present invention provides a technical solution:

example 1:

as shown in fig. 1 and 2, a multi-point grouting anchor rod includes a hollow anchor rod body 1, a grouting multi-way joint 2, and a pressure generator 3 for outputting an instantaneous high pressure into the hollow anchor rod body 1;

the rod body of the hollow anchor rod body 1 is provided with at least one grouting side hole 4 along the axial direction, and the grouting side hole 4 is provided with a sealing plug 5 matched with the grouting side hole;

the pressure generator 3 is connected with the hollow anchor rod body 1 through a grouting multi-way joint 2.

The pressure generator 3 is an air cannon. The application of instantaneous high pressure generated by an air cannon to anchor the anchor rod is the first example in the field and has pioneering significance.

Here, there are 14 side grouting holes provided in the drawing. It should be noted that the number of grouting side holes is set according to the actual bolt length.

The grouting multi-way connector 2 is a three-way connector, three connectors of the three-way connector are respectively a hollow anchor rod body 1 connector, a grouting port and a pressure generator 3 connector, as shown in fig. 1, A, B, C in fig. 1 respectively represents the hollow anchor rod body connector, the grouting port and the pressure generator connector.

The working principle is as follows: the hollow anchor rod body 1 is firstly installed in the anchor hole 6, then the hollow anchor rod body 1 is grouted through the grouting multi-way joint 2, and due to the effect of the sealing plug 5, grout in the hollow anchor rod body 1 only enters the anchor hole 6 from a grouting hole at the end part of the hollow anchor rod body 1 (a drill bit or an anchor head at the end part of the anchor rod is provided with a grouting hole, the structural characteristics are common knowledge in the field, and the detailed description is omitted). The grout entering the anchor hole 6 anchors the top of the hollow anchor body 1 (the grout stops after a certain amount (the amount that can anchor the top of the hollow anchor body 1) is injected). The grouting in the process aims to ensure that enough grout is reserved in the anchor hole 6 at the top of the hollow anchor rod body 1 to anchor the top of the hollow anchor rod body 1, and the grout cannot flow to the top of the hollow anchor rod body 1 after the grouting side hole 4 is opened.

After the top of the hollow anchor rod body 1 is anchored, instantaneous high pressure is output into the hollow anchor rod body 1 through an air cannon. Instantaneous high pressure (expansion shock wave suddenly released by an air cannon) in the hollow anchor rod body 1 acts on the sealing plug 5, so that static friction force between the sealing plug 5 and the grouting side hole 4 is overcome, the sealing plug 5 is ejected out, and the sealing plug 5 falls into the anchor hole 6. And then grouting into the hollow anchor rod body 1 again, wherein grout in the hollow anchor rod body 1 enters the anchor holes 6 from the plurality of grouting side holes 4, and then the whole rod body of the hollow anchor rod body 1 is anchored.

If the grouting holes or part of the grouting side holes 4 are blocked, the residual unblocked grouting holes can still finish grouting, and grout is grouted back to the hole openings of the anchor holes 6.

According to the invention, during grouting, the grouting efficiency is improved through multi-point grouting, the problem that grouting cannot be carried out when a grouting hole is blocked and the problem that whether grouting is in place cannot be judged because the grouting liquid wraps fragments to block a grouting channel during grouting are solved, and the used grouting liquid is the grouting liquid which meets the standard specification and has a water-cement ratio of 0.35-0.4, so that the anchoring effect is effectively ensured; meanwhile, the sealing plug 5 is opened by instantaneous pressure, so that the condition that when grouting is carried out on the end part of the hollow anchor rod body 1, the sealing plug 5 is automatically opened under the grouting pressure and grout cannot be injected into the end part of the hollow anchor rod body 1 can be avoided.

Further, the hollow anchor rod body 1 is a hollow self-drilling anchor rod, a mechanical expanding shell type anchor rod or a common hollow anchor rod. The hollow self-drilling anchor rod means that the end part of the anchor rod is provided with a drill bit, the mechanical expanding shell type anchor rod or the common hollow anchor rod means that the end part of the anchor rod is provided with an anchor head, and the top anchoring of the hollow anchor rod body 1 means that the hollow anchor rod body 1 is provided with one end of the drill bit or the anchor head.

When the hollow anchor rod body 1 is a hollow self-drilling anchor rod: the installation of the hollow anchor rod body 1 and the anchor hole 6 is realized by the self-drilling of the anchor rod, and the operation after the installation is as above. When the hollow anchor rod body 1 drills, due to the arrangement of the sealing plug 5, cooling water can still enter the drill bit from the inside of the hollow anchor rod body 1 to cool and lubricate the drill bit.

When the hollow anchor rod body 1 is a mechanical expanding shell type anchor rod or a common hollow anchor rod: the anchor hole 6 is first drilled by a drill, and after removal of the drill, the hollow shank 1 is inserted into the anchor hole 6 to complete the strand installation, the operation after installation being as described above.

Example 2:

the embodiment is a multipoint grouting process based on the multipoint grouting anchor rod in embodiment 1, and the multipoint grouting process comprises the following steps:

s10, mounting the hollow anchor rod body 1: the hollow anchor rod body 1 is positioned in the anchor hole 6 to prepare for grouting;

s101, self-drilling installation: the hollow anchor rod body 1 drills an anchor hole 6 through a drill bit at the end part, and when the drill bit is in place, the hollow anchor rod body 1 is in place; wherein, the hollow anchor rod body 1 is a hollow self-drilling anchor rod;

s11, pressure generator 3 mounting: communicating a pressure generator 3 with the interior of the hollow anchor rod body 1 through a grouting multi-way connector 2, wherein the pressure generator 3 is an air cannon;

s12, top grouting: grouting into the hollow anchor rod body 1 through the grouting multi-way connector 2, and enabling the grout to enter the anchor hole 6 through a grouting hole in the end part of the hollow anchor rod body 1 to anchor the end part of the hollow anchor rod body;

s20, opening the sealing plug 5: outputting instantaneous high pressure into the hollow anchor rod body 1 through a pressure generator 3 to separate a sealing plug 5 from a grouting side hole 4 and enable the separated sealing plug 5 to enter an anchor hole 6;

s30, multipoint grouting: grouting into the hollow anchor rod body 1 through the grouting multi-way connector 2, wherein grout enters the anchor hole 6 from the end part of the hollow anchor rod body 1 and the plurality of grouting side holes 4.

Example 3:

the present embodiment is different from embodiment 2 in that,

s10, mounting the hollow anchor rod body 1: the hollow anchor rod body 1 is positioned in the anchor hole 6 to prepare for grouting;

s102, inserting rod installation: drilling an anchor hole 6 through a drilling tool, and withdrawing after drilling the anchor hole 6 through the drilling tool; inserting the hollow anchor rod body 1 into the anchor hole 6 until the hollow anchor rod body 1 is in place; wherein, the hollow anchor rod body 1 is a mechanical expanding shell type anchor rod or a common hollow anchor rod;

s11, pressure generator 3 mounting: communicating a pressure generator 3 with the interior of the hollow anchor rod body 1 through a grouting multi-way connector 2, wherein the pressure generator 3 is an air cannon;

s12, top grouting: grouting into the hollow anchor rod body 1 through the grouting multi-way connector 2, and enabling the grout to enter the anchor hole 6 through a grouting hole in the end part of the hollow anchor rod body 1 to anchor the end part of the hollow anchor rod body;

s20, opening the sealing plug 5: outputting instantaneous high pressure into the hollow anchor rod body 1 through a pressure generator 3 to separate a sealing plug 5 from a grouting side hole 4 and enable the separated sealing plug 5 to enter an anchor hole 6;

s30, multipoint grouting: grouting into the hollow anchor rod body 1 through the grouting multi-way connector 2, wherein grout enters the anchor hole 6 from the end part of the hollow anchor rod body 1 and the plurality of grouting side holes 4.

Example 4:

the present embodiment is different from embodiment 1 in that, as shown in fig. 3, the hollow anchor rod body 1 may be, but not limited to, a form in which a plurality of hollow anchors are connected by a connecting sleeve 7, and when the hollow anchor rod body 1 is a combination form of a plurality of anchors, a grouting side hole may be provided on the anchor rod or on the connecting sleeve 7 (in fig. 3, a grouting side hole is provided on the connecting sleeve).

The foregoing is illustrative of the preferred embodiments of this invention, and it is to be understood that the invention is not limited to the precise form disclosed herein and that various other combinations, modifications, and environments may be resorted to, falling within the scope of the concept as disclosed herein, either as described above or as apparent to those skilled in the relevant art. And that modifications and variations may be effected by those skilled in the art without departing from the spirit and scope of the invention as defined by the appended claims.

Claims (8)

1. Multiple spot slip casting stock, its characterized in that: comprises a hollow anchor rod body, a grouting multi-way joint and a pressure generator for outputting instantaneous high pressure into the hollow anchor rod body;

the rod body of the hollow anchor rod body is provided with at least one grouting side hole along the axial direction, and the grouting side hole is provided with a sealing plug matched with the grouting side hole;

the pressure generator is connected with the hollow anchor rod body through a grouting multi-way joint.

2. A multi-point grouting bolt according to claim 1, wherein: the pressure generator is an air cannon.

3. A multi-point grouting bolt according to claim 1, wherein: the hollow anchor rod body is a hollow self-drilling anchor rod, a mechanical expanding shell type anchor rod or a common hollow anchor rod.

4. A multipoint grouting process based on a multipoint grouting anchor rod according to any one of claims 1-3, characterized in that: the method comprises the following steps:

s10, mounting a hollow anchor rod body: positioning the hollow anchor rod body in the anchor hole to prepare for grouting;

s20, opening the sealing plug: outputting instantaneous high pressure into the hollow anchor rod body through a pressure generator to separate the sealing plug from the grouting side hole and enable the separated sealing plug to enter the anchor hole;

s30, multipoint grouting: and grouting into the hollow anchor rod body through the grouting multi-way connector, wherein the grout enters the anchor hole from the end part of the hollow anchor rod body and the plurality of grouting side holes.

5. The multipoint grouting process according to claim 4, characterized in that: before the step S20, the method further includes the following steps:

s11, installing a pressure generator: the pressure generator is communicated with the interior of the hollow anchor rod body through the grouting multi-way connector, wherein the pressure generator is an air cannon.

6. The multipoint grouting process of claim 5, characterized in that: before the step S20, the method further includes the following steps:

s12, top grouting: and grouting into the hollow anchor rod body through the grouting multi-way connector, wherein the grout enters the anchor hole through the grouting hole at the end part of the hollow anchor rod body to anchor the end part of the hollow anchor rod body.

7. The multipoint grouting process according to claim 4, characterized in that: the step S10 includes the following steps:

s101, self-drilling installation: drilling an anchor hole in the hollow anchor rod body through a drill bit at the end part, wherein when the drill bit is in place, the hollow anchor rod body is in place; wherein, the hollow anchor rod body is a hollow self-drilling anchor rod.

8. The multipoint grouting process according to claim 4, characterized in that: the step S10 includes the following steps:

s102, inserting rod installation: drilling an anchor hole through a drilling tool, and withdrawing after drilling the anchor hole through the drilling tool; inserting the hollow anchor rod body into the anchor hole until the hollow anchor rod body is in place; wherein, the hollow anchor rod body is a mechanical expanding shell type anchor rod or a common hollow anchor rod.

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