CN104763454A - Built-in type full-length anticorrosion anchor rod - Google Patents

Abstract

The invention relates to an anchor rod of geotechnical engineering, in particular to a built-in type full-length anticorrosion anchor rod. One end of a hollow threaded rod is connected with the front end of the anchor rod, the other end of the hollow threaded rod is connected with an external anchor head, and an aligner is mounted on the hollow threaded rod; the external anchor rod comprises a concave tray, wherein the concave tray comprises a tray; a concave cavity is connected in the center of the tray; the concave cavity of the concave tray is connected with the hollow threaded rod through a gasket and a nut, and a concave sealing cap is arranged in the concave cavity; the concave tray is fixed on a rack wall through a cement steel bolt; a grouting and gas exhausting tube is mounted in the concave cavity of the concave tray; a protective layer is arranged at the outer side of the tray of the concave tray. According to the built-in type full-length anticorrosion anchor rod, the grouting and fixing is used for realizing anti-corrosion protection on the rod body, and the external anchor rod realizes anti-corrosion protection on the external anchor head, and the anti-corrosion protection of the whole anchor rod is realized by sealing through a protective layer, and the built-in type full-length anticorrosion anchor rod is especially suitable for perpetual rock-soil anchoring projects with high anti-corrosion requirements.

Description

Built-in full-length anti-corrosion anchor

technical field

The invention relates to an anchor rod for geotechnical engineering, in particular to a built-in full-length anti-corrosion anchor rod.

Background technique

Anchor bolt is a main support technology in underground engineering, mining engineering, foundation pit and slope engineering involved in geotechnical engineering. It has a wide range of applications and good reinforcement effect. However, with the continuous increase of engineering construction, the geological conditions faced by the engineering involving anchorage are becoming more and more complex, and new problems are constantly emerging. Among them, the corrosion of anchor rods is a key problem that needs to be solved urgently.

Since the stratum or groundwater is always slightly or heavily corrosive to concrete and anchors, it is difficult to effectively guarantee the durability and bearing capacity of permanent anchorage, anti-floating or pull-out engineering, and anti-corrosion treatment is required for anchors. In the process of design and manufacture of traditional anchor bolts, the anti-corrosion problem of anchor bolts is seldom considered. Some anti-corrosion bolts that have been put into use also have problems such as complex structure and poor corrosion resistance.

The anti-corrosion technical measures of anchor bolts mainly include isolation and insulation. The main methods include galvanized layer of anchor bolts, epoxy resin coating, grouting consolidation protection, casing wrapping protection, etc., among which grouting consolidation is the most important anti-corrosion method. one. Most of the research on anti-corrosion bolts still focuses on the anti-corrosion research of the rod body, and less involves the anti-corrosion research of the outer anchor head. Such as the anti-corrosion metal anchor disclosed by the application number CN97217266.1, the processing procedure of its surface electroplating layer is complicated, the thickness is very small, and the collision and scraping in storage, transportation and construction can easily make the surface anti-corrosion layer fall off and fail; the application number is 201220476433.0 publication A thermoplastic anti-corrosion bolt support device for mines, which needs to heat and melt thermoplastic materials during anti-corrosion operations, the operation is cumbersome, and the structure is too complicated, and the practicability is poor; the application number is 201220609725.7 A capsule-type anti-corrosion anchor, its The anti-corrosion structure is a kind of impermeable bag, which reduces the holding force between the anchor rod and the cement mortar, affects the anchoring quality, and is easy to cause the bag to rupture during construction and lose the anti-corrosion effect.

Contents of the invention

In view of the above technical problems, the present invention provides a built-in full-length anti-corrosion anchor, which can effectively prevent the anti-corrosion of the anchor. The specific technical solution is:

The built-in full-length anti-corrosion anchor includes a hollow threaded rod, the front end of the anchor rod, an outer anchor head, and a protective layer; one end of the hollow threaded rod is connected to the front end of the anchor rod, and the other end is connected to the outer anchor head. There is a centering device; the outer anchor head includes an inner concave tray, the inner concave tray includes a tray, the center of the tray is connected to the cavity, and the cavity of the inner concave tray is connected to the hollow threaded rod through a gasket and a nut, and the cavity is formed by the inner concave shaped cap; the side of the inner concave tray close to the rock wall has serrated thorns, the inner concave tray is fixed on the rock wall by cement steel nails, and there are small holes in the cavity of the inner concave tray for The grouting exhaust pipe is installed, and there is a protective layer on the outside of the tray of the concave tray.

The front end of the anchor rod is a solid threaded rod, and the solid threaded rod is connected to the hollow threaded rod through a connecting sleeve. There is a slurry blocker. The slurry blocker is a ring, and the ring has a trumpet-shaped baffle.

Use the early-strength anchoring agent to anchor the solid threaded rod. After the early-strength anchoring agent reaches a certain strength requirement, the anchor rod can be tensioned and prestressed, and cement mortar can be poured through the hollow cavity of the hollow threaded rod to achieve full-length anchoring.

Alternatively, the front end of the anchor rod is a shell-expanding anchor head, and the shell-expanding anchor head is connected to the hollow threaded rod through threads.

The expansion shell anchor head adopts ordinary steel expansion shell. After the anchor rod is sent into the drill hole, the top of the expansion shell anchor head is compressed and prestressed, and the cement mortar is poured through the hollow cavity of the hollow threaded rod. Achieving full length anchorage.

The built-in full-length anti-corrosion bolt provided by the present invention realizes the anti-corrosion protection of the bolt body through grouting consolidation, and realizes the anti-corrosion protection of the outer anchor head through the built-in outer anchor head. The "hidden anchor" outer anchor The head will not be exposed outside the drill hole, but built into the drill hole. While realizing the anti-corrosion of the entire length of the anchor rod, it also saves the space occupied by the original external anchor head, effectively increasing the construction work space , reducing the interference and adverse effects on construction, and realizing the anti-corrosion protection of the entire anchor rod through the sealing of the protective layer, the anchor rod can effectively resist corrosion, the anti-corrosion performance is durable and reliable, and the application range is wide, especially suitable for high requirements on anti-corrosion permanent geotechnical anchoring works.

Description of drawings

Fig. 1 is the structural representation of embodiment 1 of the present invention;

Fig. 2 is a partial structural schematic diagram of Embodiment 1 of the present invention.

Fig. 3 is a schematic structural view of the centering device of the present invention;

Fig. 4 is the structural representation of embodiment 2 of the present invention;

Fig. 5 is a schematic diagram of the structure of the concave tray of the present invention.

specific embodiment

The specific embodiment of the present invention will be described with reference to the accompanying drawings.

Example 1

As shown in Figure 1, the built-in full-length anti-corrosion anchor includes a hollow threaded rod 16, the front end of the anchor rod, an outer anchor head, and a protective layer 3; one end of the hollow threaded rod 16 is connected to the front end of the anchor rod, and the other end is connected to the outer anchor rod. The anchor head is connected, and a centering device 17 is installed on the hollow threaded rod 16;

The outer anchor head includes an inner concave tray 4, the inner concave tray 4 includes a tray, and the center of the tray is connected to a cavity, and the cavity of the inner concave tray 4 is connected to the hollow threaded rod 16 through a gasket 8 and a nut 6, and the nut 6 is a damping The nut is made of Q235A carbon structural steel with a tensile strength not less than 375MPa. The concave cavity is sealed by the concave-shaped sealing cap 2, and butter 5 is filled in the sealed space; the side of the concave-shaped tray 4 close to the rock wall has serrated thorns, and the concave-shaped tray 4 is fixed on the rock by cement steel nails 1. On the wall, small holes are left on the cavity of the inner concave tray 4 for installing the grouting exhaust pipe 7, and the outer side of the inner concave tray 4 has a protective layer 3.

As shown in Figure 2, the front end of the anchor rod includes a solid threaded rod 13, the solid threaded rod 13 is connected with the hollow threaded rod 16 through the connecting sleeve 10, the middle part of the connecting sleeve 10 has a grout hole 15, and the grout hole 15 is connected to the hollow threaded rod 16. The hollow cavity of the hollow threaded rod 16 is connected, and the outer wall of the connecting sleeve 10 has a slurry trap 14 . The slurry blocker 14 is a ring, and the ring has a trumpet-shaped baffle.

The solid threaded rod 13 and the hollow threaded rod 16 form a rod body, and the rod body is galvanized. The outer diameter of the hollow threaded rod 16 is 25-40mm, and the wall thickness is 5mm; The length ratio of the solid threaded rod 13 to the hollow threaded rod 16 is 1:6 to 1:2.

The connecting sleeve 10 is made of carbon structural steel, the tensile strength is greater than that of the solid threaded rod 13 and the hollow threaded rod 16, and the outer diameter is 10-15mm larger than that of the hollow threaded rod 16; The number of holes 15 is not less than 2.

The slurry blocker 14 is made of plastic material, and is connected with the connecting sleeve 10, and the outer edge of the baffle is attached to the hole wall.

As shown in Figure 3, the centering device 17 is a cylinder with a positioning ruler on the outer surface, made of plastic, the inner surface of the centering device 17 is connected with the hollow threaded rod 16, and the outer edge is in contact with the hole wall.

Bolt installation: use a drilling machine to drill a hole on the rock wall and clean the hole, put an early-strength anchoring agent 12 at the bottom of the hole; secondly, use a drilling machine to install the built-in full-length anti-corrosion bolt by means of rotary stamping, etc. In place, the solid threaded rod 13 at the front end of the built-in full-length anti-corrosion anchor squeezes and stirs the early-strength anchoring agent, fills it densely, and forms an early-strength anchoring body; after the early-strength anchoring body reaches a certain strength, install the outer anchor head, press It is required to apply prestress; finally, grouting should be carried out, and the cement mortar 9 in the borehole should be filled densely to complete the bolt installation.

Working principle: The rod body of the built-in full-length anti-corrosion anchor is protected by cement mortar consolidation, which is one of the most important anti-corrosion methods at present. In the case of uniform and dense filling, the anti-corrosion effect is good; The concave sealing cap 2 is sealed, and the way of filling butter in the middle achieves the anticorrosion of the outer anchor head; the protective layer 3 is sealed and wiped on the rock surface near the drilling hole by cement slurry or concrete. The strength of the protective layer 3 is not lower than C30, and the thickness of the protective layer is Not less than 50mm, the inner concave tray 4 and the entire anchoring system are sealed and protected to achieve the purpose of isolating from outside air and water. The anti-corrosion function of the bolt is realized through the three-layer anti-corrosion system, and the anti-corrosion effect is durable and reliable.

Example 2

As shown in Figure 4, the built-in full-length anti-corrosion anchor includes a hollow threaded rod 16, the front end of the anchor rod, an outer anchor head, and a protective layer 3; one end of the hollow threaded rod 16 is connected to the front end of the anchor rod, and the other end is connected to the outer anchor rod. The anchor head is connected, and a centering device 17 is installed on the hollow threaded rod 16;

The outer anchor head includes an inner concave tray 4, and the inner concave tray 4 includes a tray. The concave sealing cap 2 is filled with butter 5 in the sealed space; the inner concave tray 4 has serrated thorns on the side of the tray close to the rock wall, and the inner concave tray 4 is fixed on the rock wall by cement steel nails 1. The concave cavity of the tray 4 has small holes for installing the grouting exhaust pipe 7, and the grouting exhaust pipe 7 is a plastic pipe, which has both grouting and exhaust functions. There is a protective layer 3 on the outside of the inner concave tray 4 .

The front end of the anchor rod includes a shell-expanding anchor head 18, which is connected to the hollow threaded rod 16 through threads.

Manpower or machines are used to press the outer end of the anchor rod, so that the shell-type anchor head 18 expands and clings to the hole wall to form a preliminary anchoring force, and prestress can be applied as required by jacks and other tools; finally, grouting , the cement mortar 9 in the borehole is filled densely, and the bolt installation is completed.

In addition, as shown in Figure 5, the cavity of the concave tray 4 of the two embodiments can be a cylindrical cavity or a conical cavity, and the outer wall of the conical cavity is not attached to the wall of the drilled hole. together, but at an angle.

The built-in full-length anti-corrosion anchor rods of Embodiment 1 and Embodiment 2 can be installed downwards or upwards. When installed downwards, the cement mortar 9 is injected into the hollow cavity of the hollow threaded rod 16, and is filled densely from the bottom of the borehole to the hole, and the air is discharged from the grouting exhaust pipe 7; when installed upwards, the cement mortar 9 Enter the borehole from the grouting exhaust pipe 7, and fill it from the hole to the bottom of the borehole, and the air is discharged from the hollow cavity of the hollow threaded rod 16.

Claims (4)

1. Built-in full-length anti-corrosion anchor, characterized in that: it includes a hollow threaded rod, the front end of the anchor rod, an outer anchor head, and a protective layer; one end of the hollow threaded rod is connected to the front end of the anchor rod, and the other end is connected to the outer anchor head , a centering device is installed on the hollow threaded rod; the outer anchor head includes an inner concave tray, the inner concave tray includes a tray, the center of the tray is connected to the cavity, and the cavity of the inner concave tray is connected to the hollow threaded rod through a gasket and a nut , the concave cavity is sealed by the concave-shaped sealing cap; the side of the concave-shaped tray close to the rock wall has serrated thorns, the concave-shaped tray is fixed on the rock wall by cement steel nails, the concave cavity of the concave-shaped tray A small hole is left for installing the grouting exhaust pipe, and there is a protective layer on the outside of the inner concave tray. 2. The built-in full-length anti-corrosion anchor according to claim 1, characterized in that: the front end of the anchor is a solid threaded rod, the solid threaded rod is connected to the hollow threaded rod through a connecting sleeve, and the middle part of the connecting sleeve has The slurry outlet is connected with the hollow cavity of the hollow threaded rod, and the outer wall of the connecting sleeve is provided with a slurry stopper. 3. The built-in full-length anti-corrosion bolt according to claim 2, characterized in that: the slurry trap is a ring, and the ring has a trumpet-shaped baffle. 4. The built-in full-length anti-corrosion anchor according to claim 1, characterized in that: the front end of the anchor is a shell-expanding anchor head, and the shell-expanding anchor head is connected to the hollow threaded rod through threads.