CN112127225A - Anti-floating self-repairing anchoring device, light soil roadbed structure and construction method - Google Patents

Abstract

The invention discloses an anti-floating self-repairing anchoring device, a light soil roadbed structure and a construction method, wherein the technical scheme is as follows: the self-healing anchor rod comprises an anchor head, a concrete anchor rod section and a self-healing anchor rod section which are connected into a whole, wherein a plurality of head expanding anchors are arranged at intervals outside the concrete anchor rod section; the road foundation is characterized by also comprising road foundation soil, wherein a thick gravel cushion layer, a light soil layer and a concrete plate are sequentially arranged above the road foundation soil from bottom to top; the concrete anchor rod section is embedded in the roadbed soil, and the self-healing anchor rod section is embedded in the light soil layer and the concrete slab. The invention solves the problems of insufficient anti-pulling force, overlarge anchor rod length, easy structural crack generation of the anchoring device in the anti-pulling process and the like in the prior art, can improve the anti-floating performance of the lightweight soil roadbed, reduces the displacement generated by pulling, and enhances the durability of the anchoring device.

Description

Anti-floating self-repairing anchoring device, light soil roadbed structure and construction method

Technical Field

The invention relates to the field of wood engineering anchoring, in particular to an anti-floating self-repairing anchoring device, a light soil roadbed structure and a construction method.

Background

With the development of road engineering, the foam light soil roadbed has the advantages of effectively reducing additional stress generated by roadbed load on the roadbed, reducing the total settlement of the roadbed and the like, and is widely used in roadbed backfill engineering. However, when the light soil is applied to sections such as a water accumulation low-lying section, a water passing roadbed, a riverbed and the like, underground water generates large buoyancy on the light roadbed when the underground water level is high because the density of the light soil is small, so that the roadbed floats upwards, the pavement structure is damaged, and the traffic safety is seriously influenced.

The inventor finds that the existing anti-floating measures mostly adopt the mode of additionally arranging a grouting anchor rod or a miniature pile, however, because the anti-pulling capacity of the soil layer grouting anchor rod is low, the length of the anchor rod is generally longer for meeting the anti-pulling requirement. Meanwhile, the grouting body is inevitably subjected to the repeated action of the uplifting force, so that fine cracks are generated, the corrosion of the anchor rod is damaged, and the durability of the anti-floating structure is reduced or even the anti-floating structure fails.

Disclosure of Invention

Aiming at the defects in the prior art, the invention aims to provide the anti-floating self-repairing anchoring device, the light soil roadbed structure and the construction method, solves the problems that the anti-pulling force is insufficient, the length of the anchor rod is too large, the anchoring device is easy to generate structural cracks in the anti-pulling process and the like in the prior art, can improve the anti-floating performance of the light soil roadbed, reduce the displacement generated by pulling, and enhance the durability of the anchoring device.

In order to achieve the purpose, the invention is realized by the following technical scheme:

in a first aspect, an embodiment of the present invention provides an anti-floating self-repairing anchoring device, which includes an anchor head, a concrete anchor rod section, and a self-healing anchor rod section that are connected into a whole, where a plurality of head-expanding anchors are arranged at intervals outside the concrete anchor rod section.

As a further implementation mode, anchor bar bundles are arranged inside the concrete anchor rod section and the self-healing anchor rod section, and the outer sides of the anchor bar bundles are fastened by a plurality of stirrups.

As a further implementation, the anchor bar bundle includes a central bar and peripheral bars equally spaced around the central bar.

As a further implementation, the center steel bar exceeds the surface of the self-healing anchor rod section by a set length to connect the anchor plates.

As a further implementation, the diameter of the central rebar is greater than the diameter of the peripheral rebars.

As a further implementation mode, common concrete is filled outside the anchor bar bundle to form a concrete anchor rod section, and microcapsule concrete is filled outside the anchor bar bundle to form a self-healing anchor rod section.

As a further implementation manner, the head-expanding anchor comprises a geomembrane bag arranged on the outer layer, and concrete is filled in the geomembrane bag.

In a second aspect, the embodiment of the invention also provides an anti-floating light soil roadbed structure, which comprises the anchoring device.

As a further implementation mode, the road foundation soil is further included, and a thick gravel cushion layer, a light soil layer and a concrete slab are sequentially arranged above the road foundation soil from bottom to top;

the concrete anchor rod section is embedded in the roadbed soil, and the self-healing anchor rod section is embedded in the light soil layer and the concrete slab.

In a third aspect, an embodiment of the present invention further provides a construction method of an anti-floating self-repairing anchoring device, including:

drilling by using a hole expanding device, and sleeving the geomembrane bag on the head of the hole expanding device for expanding holes;

moving out the reaming device, inserting the anchor head and the anchor bar bundle which are connected into a whole into the hole, and sleeving a sleeve outside the anchor bar bundle;

grouting, wherein in the grouting process, the sleeve rises along with the grout;

filling common concrete for grouting, and stopping grouting when the common concrete reaches the joint part of the foundation soil and the light soil; filling microcapsule concrete until the microcapsule concrete reaches a concrete slab, and stopping grouting;

and inserting the reinforcing steel bar bundles reserved at the top end of the self-healing anchor rod section into the anchor plate, and performing concrete curing.

The beneficial effects of the above-mentioned embodiment of the present invention are as follows:

(1) according to one or more embodiments of the invention, microcapsule concrete is doped in the anchor rod part, so that the self-repairing capability of the anchoring device is improved, and the durability of the anchoring device is improved;

(2) according to one or more embodiments of the invention, the geomembrane bag is preset, so that the hole expanding forming is easy, the quality problem caused by the conventional hole expanding is prevented, and the hole expanding stability is improved;

(3) according to one or more embodiments of the invention, the light soil and the roadbed soil layer are anchored by the anchoring device, so that the floating problem in the foam light soil roadbed can be effectively prevented, and the structural durability of the light soil roadbed can be improved; the construction operability is good, the construction speed is high, the anchoring forming quality is high, and the diameter breaking phenomenon can not occur.

Drawings

The accompanying drawings, which are incorporated in and constitute a part of this specification, are included to provide a further understanding of the invention, and are incorporated in and constitute a part of this specification, illustrate exemplary embodiments of the invention and together with the description serve to explain the invention and not to limit the invention.

FIG. 1 is a schematic illustration of an anchoring device according to one or more embodiments of the present invention in use in a refill lightweight subgrade;

fig. 2 is a cross-sectional schematic view of a bolt segment according to one or more embodiments of the present invention;

FIG. 3 is a schematic illustration of an anchoring device according to one or more embodiments of the present invention;

FIG. 4 is a schematic illustration of the internal structure of an anchoring device according to one or more embodiments of the present invention;

FIG. 5 is a schematic illustration of the present invention at a point in time of casing pull-up during concrete placement in accordance with one or more embodiments;

FIG. 6 is a schematic illustration of the effect of a reaming operation according to one or more embodiments of the invention;

fig. 7 is a schematic representation of a geomembrane bag construction according to one or more embodiments of the present invention;

the self-healing anchor rod comprises an anchor head 1, an anchor head 2, a central steel bar 3, a peripheral steel bar 4, a sleeve pipe 5, a stirrup 6, a concrete anchor rod section 7, a self-healing anchor rod section 8, a head expanding anchor 9, an anchor plate 10, a concrete plate 11, a light soil layer 12, a thick gravel cushion layer 13, roadbed soil 14, a pore-forming layer 15 and a geomembrane bag.

Detailed Description

It should be noted that the following detailed description is exemplary and is intended to provide further explanation of the disclosure. Unless defined otherwise, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this application belongs.

It is noted that the terminology used herein is for the purpose of describing particular embodiments only and is not intended to be limiting of example embodiments according to the present application. As used herein, the singular forms "a", "an", and/or "the" are intended to include the plural forms as well, and it should be understood that when the terms "comprises" and/or "comprising" are used in this specification, they specify the presence of stated features, steps, operations, devices, components, and/or combinations thereof;

for convenience of description, the words "up", "down", "left" and "right" in this application, if any, merely indicate correspondence with the directions of up, down, left and right of the drawings themselves, and do not limit the structure, but merely facilitate the description of the invention and simplify the description, and do not indicate or imply that the referenced device or element must have a particular orientation, be constructed and operated in a particular orientation, and therefore should not be construed as limiting the application.

The terms "mounted", "connected", "fixed", and the like in the present application should be understood broadly, and for example, the terms "mounted", "connected", and "fixed" may be fixedly connected, detachably connected, or integrated; the two components can be connected directly or indirectly through an intermediate medium, or the two components can be connected internally or in an interaction relationship, and the terms can be understood by those skilled in the art according to specific situations.

The first embodiment is as follows:

the embodiment provides an anti-floating self-repairing anchoring device, which comprises an anchor head 1, a head-expanding anchor 8, a concrete anchor rod section 6 and a self-healing anchor rod section 7, wherein the tail end of the anchor head 1 is sequentially connected with the concrete anchor rod section 6 and the self-healing anchor rod section 7; a plurality of head-expanding anchors 8 are arranged outside the concrete anchor rod section 6.

Specifically, the anchor head 1 is a conical metal anchor head. The tail end (back to the conical tip) of the anchor head 1 is connected with an anchor bar bundle, and the anchor bar bundle is composed of a central steel bar 2 and a peripheral steel bar 3. The anchor head 1 and the anchor tendon bundles can be integrally connected or respectively connected. In this embodiment, the tendon bundles are welded to the anchor head 1.

As shown in fig. 2, the central reinforcing bar 2 is connected to the central position of the anchor head 1, and the peripheral reinforcing bars 3 are equally spaced around the central reinforcing bar 2 and parallel to the central reinforcing bar 2. The number of the peripheral reinforcing bars 3 is selected according to the actual anchoring requirements, and in the present embodiment, four peripheral reinforcing bars 3 are provided. The diameter of the central steel bar 2 is larger than that of the peripheral steel bars 3.

As shown in fig. 4, a plurality of stirrups 5 are uniformly provided at intervals along the longitudinal direction outside the anchor bar bundle, and the anchor bar bundle is hooped by the stirrups 5. The outside of the tendon bundles is coated with different types of concrete to form a concrete anchor section 6 and a self-healing anchor section 7. The end part of the central steel bar 2 protrudes out of the top end surface of the self-healing anchor rod section 7 so as to be connected with an anchor plate 9; the anchor plate 9 is perpendicular to the anchor tendon bundles.

The outer surfaces of the reinforcing steel bar bundle and the stirrup 5 consisting of the central reinforcing steel bar 2 and the peripheral reinforcing steel bar 3 are coated with epoxy resin coatings, and the epoxy resin coatings have good corrosion resistance. In this embodiment, the diameter of the central reinforcing bar 2 is 25mm, the diameter of the peripheral reinforcing bars 3 is 20mm, and the diameter of the stirrups 5 is 28 mm. The length of the whole anchoring device is 15-35m, and the specific length is determined according to the field situation. The diameters of the concrete anchor rod section 6 and the self-healing anchor rod section 7 are 15-30cm, and the specific diameters are determined according to the field working conditions.

Further, the concrete anchor rod section 6 is filled with common concrete, and the self-healing anchor rod section 7 is filled with microcapsule concrete. Compared with common concrete, the microcapsule concrete has the same water and cement mixing amount, and the mixing amount of the sand and the capsules in the microcapsule concrete is the same as that of the sand in the common concrete. The microcapsule concrete is blended with a certain amount of microcapsules. The microcapsule in the microcapsule concrete consists of a capsule wall and a capsule core, wherein the capsule wall is made of polyurethane material, and the capsule core is made of calcium sulphoaluminate cement expansion material and sodium carbonate material.

Preparing the microcapsule concrete by mass ratio: water, cement, sand and capsules, 6.6:22:41.8: 2.2. The common concrete material is prepared from water, cement and sand in a mass ratio of 6.6: 22:44. The microcapsules are uniformly distributed in the microcapsule concrete, and the release mode of the microcapsules is that when the anchoring structure generates fine deformation, the anchoring structure generates cracks, and the microcapsules at the cracks are broken. The microcapsule is broken, and the calcium sulphoaluminate cement expansion material and the sodium carbonate material flow out to react with water and concrete in the gap. The reaction product fills and repairs the gap and recovers the mechanical property of the concrete, and simultaneously recovers the mechanical property of the anchoring device.

The concrete anchor rod section 6 and the self-healing anchor rod section 7 are formed by sleeving the sleeve 4 outside the anchor tendon bundle and then grouting. As shown in fig. 5, the sleeve 4 is sleeved outside the anchor bar bundle and can move relative to the anchor bar bundle. During grouting, the sleeve 4 is slowly lifted along with the gradual rise of concrete slurry, the sleeve 4 is always kept at the upper position of the concrete rising liquid level, and the sleeve 4 and the concrete liquid level are relatively static.

According to the actual situation, 2-3 head expanding anchors 8 can be arranged. In the embodiment, two anchor heads 8 are provided, wherein one anchor head 8 is located behind the anchor head 1, and the other anchor head 8 is spaced from the previous anchor head 8 by a certain distance to form a pressure dispersion type anchor head. The head-expanding anchor 8 is cylindrical, and the diameter of the head-expanding anchor is larger than the diameter of the concrete anchor section 6 and the diameter of the self-healing anchor section 7. In the present embodiment, the diameter of the anchor 8 is 600-800 mm; the length of the single anchor 8 is 1-2 m.

The outer layer of the head-expanding anchor 8 is a geomembrane bag 15, the structure of the geomembrane bag 15 is shown in fig. 7, and the head-expanding anchor 8 is formed by injecting slurry into the geomembrane bag 15.

In the embodiment, the problems of insufficient uplift resistance, overlarge anchor rod length and the like are effectively solved by arranging the expanded head anchor 8, burying the expanded head anchor in foundation soil, controlling the distance between the plates, designing the size of the anchoring device and the like. The geomembrane bag 15 is arranged at the anchoring position in the reaming stage, so that the reaming and forming are easy, the soil body is prevented from collapsing and deforming, and the injected slurry body is not deformed.

Microcapsule self-healing concrete is mixed in the stock part to this embodiment, through microcapsule concrete's self-healing action, has solved the structure crack that anchor device produced at resistance to plucking in-process, has promoted anchor device's durability.

Example two:

the embodiment provides an anti-floating light soil roadbed structure, as shown in fig. 1, comprising the anchoring device of the first embodiment, further comprising roadbed soil 13, a thick gravel cushion layer 12, a light soil layer 11 and a concrete slab 10, wherein the thick gravel cushion layer 12 is laid above the roadbed soil 13, the light soil layer 11 is filled above the thick gravel cushion layer 12, and the light soil layer 11 is not filled with the roadbed soil 13 before the light soil layer 11 is filled; a concrete slab 10 is arranged above the light soil layer 11.

The layers can be laid according to actual requirements on site, and in the embodiment, the thickness of the thick gravel cushion 12 is 20cm and is arranged above underground engineering. The thickness of the light soil layer 11 is 4.2m, the thickness of the concrete plate 10 is 40cm, and the width of the thick gravel cushion layer 12, the light soil layer 11 and the concrete plate 10 is 16 m.

The anchoring means are embedded in the foundation soil 13 and extend through the light soil layer 11 up to the concrete slab 10. Wherein, anchor head 1, expand head anchor 8, concrete anchor rod section 6 are buried in road bed soil 13, and self-healing anchor rod section 7 is buried in light soil layer 11 and concrete slab 10. The top end of the self-healing anchor rod section 7 is embedded below the upper surface of the concrete slab 10, and the protruding section of the central steel bar 2 and the anchor plate 9 are located below the upper surface of the concrete slab 10.

The length of the central steel bar 2 exceeding the top of the self-healing anchor rod section 7 is not more than the thickness of the anchor plate 9. The anchor plate 9 may be a square concrete plate, a round concrete plate or other shaped concrete plate.

In the embodiment, the light soil layer 11 and the roadbed soil 13 are anchored by the anchoring device, so that the anti-floating performance of the light soil roadbed is improved, the stress generated by upward pulling is dispersed by the dispersive anchoring, and the displacement generated by pulling is reduced. The durability of the anchoring device is enhanced through the self-repairing function of the microcapsule concrete anchor rod section, and the built-in film bag is beneficial to dispersive reaming and forming. The embodiment is used for preventing the engineering harm to the pavement structure and traffic safety caused by the floating of the light soil subgrade.

Example three:

the embodiment provides a construction method of an anti-floating self-repairing anchoring device, which comprises the following steps:

the method comprises the following steps: the gross position of the void is determined by measurement in the field with a total station. And (4) determining the orientation of the drilled hole according to the design when the positioning deviation of the anchor hole is not more than 2cm, and then accurately determining the inclination angle of the drill rod by using an angle meter to ensure that the drill rod meets the design requirement.

Step two: and (3) using a long spiral drilling machine as a reaming device to drill holes for the anchoring device. Firstly, stabilizing the drill, adjusting the angle, wherein the angle is consistent with the drill rod inclination angle determined by the construction design and the goniometer. And (5) performing reaming test on the ground by drilling to reach the reaming diameter, and stabilizing.

And (5) lowering the drill bit to drill the hole, wherein the diameter of the drilled hole is slightly larger than that of the casing 4. And (4) drilling to a preset depth (an anchor head 1), stopping drilling, and slowly lifting out the spiral drilling device.

Step three: and lowering the reaming device for reaming.

Before putting the reaming device down, wrap up single geomembrane bag 15 in the head of reaming device, after preparing to accomplish, put the reaming device down and carry out the reaming to the 8 positions of reaming anchor. And when the hole is expanded to the designed diameter, the hole expansion is completed, and the hole expansion device is put out. And then wrapping the second geomembrane bag 15 at the head part of the hole expanding device, expanding the holes by adopting the steps until the second hole expanding is finished, and slowly moving the hole expanding device out of the hole.

And (3) taking hole collapse treatment measures: judging the soil condition according to a construction design drawing, if the soil condition is poor, drilling a part of anchor holes which are easy to collapse in the drilling hole by using a casing pipe slightly larger than the drilling distance at the hole opening to perform pipe following drilling so as to prevent the hole wall collapse phenomenon at the hole opening, and keeping the casing pipe length consistent with the drilling depth.

Step four: and (6) cleaning the holes. The drilling depth of the drill hole is 0.5 m higher than the design depth according to the design requirement, the anchoring effect is ensured, the air compressor finishes impact drilling, and the drill slag is blown out, so that the anchor hole cleaning effect is achieved.

Step five: and (5) lowering the anchoring device. The anchoring device is lowered into the borehole, namely the anchor head 1, the central steel bar 2, the peripheral steel bars 3, the stirrups 5 and the casing 4, the casing 4 is sleeved outside the anchor bar bundle, the front end of the casing is attached to the anchor head 1, but the casing 4 and the anchor head 1 can move relatively, as shown in fig. 5. The anchor head 1 is inserted into the un-backfilled subgrade soil 13 and the other parts (central reinforcement 2, peripheral reinforcement 3, stirrup 5, casing 4) are placed in the drilled hole 14 (shown in fig. 6).

Step six: and (6) grouting. And connecting a concrete delivery pump for grouting. During grouting, the sleeve 4 is slowly lifted along with the gradual rise of concrete slurry, the sleeve 4 is always kept at the upper position of the concrete rising liquid level, and the sleeve 4 and the concrete liquid level are relatively static.

And the grout for starting grouting is common concrete, reaches the longitudinal joint part of the unfilled roadbed soil 13 and the light soil layer 11, stops grouting the common concrete grout, and completes the pouring of the concrete anchor rod section 6 and the head-expanding anchor 8. And changing the microcapsule concrete, and starting grouting until the self-healing anchor rod section 7 is poured at the top. And a part of central steel bars 2 are reserved at the top of the self-healing anchor rod section 7 and are connected with an anchor plate 9.

The grouting pressure of the cement paste is selected to be between 3 and 15MPa according to different geological conditions of construction sites, and the lifting speed is controlled to be within the range of 45 to 60cm per minute. The lifting speed is controlled at the position of the head-expanding anchor 8 according to the diameter of the head-expanding anchor. And when the grouting reaches the top of the self-healing anchor rod section 7 and is positioned on the concrete slab 10, stopping grouting, inserting the reserved central steel bar 2 into the anchor slab 9, and waiting for finishing the concrete curing time.

And repeating the construction method until all road sections are constructed.

The above description is only a preferred embodiment of the present application and is not intended to limit the present application, and various modifications and changes may be made by those skilled in the art. Any modification, equivalent replacement, improvement and the like made within the spirit and principle of the present application shall be included in the protection scope of the present application.

Claims (10)

1. The utility model provides an anti floating selfreparing anchor device which characterized in that, is including connecting anchor head, concrete anchor pole section and the self-healing anchor pole section as an organic whole, concrete anchor pole section outside interval is equipped with a plurality of anchor heads that expand.

2. The anchoring device of claim 1, wherein the concrete anchor rod section and the self-healing anchor rod section are internally provided with anchor bar bundles, and the outer sides of the anchor bar bundles are fastened by a plurality of stirrups.

3. The anchoring device of claim 2, wherein the anchor tendon comprises a central steel bar and peripheral steel bars distributed around the central steel bar at equal intervals.

4. The anchoring device of claim 3, wherein the central steel bar extends beyond the surface of the self-healing anchor rod section by a predetermined length to connect the anchor plates.

5. The anchoring device of claim 3, wherein the diameter of the central steel bar is larger than that of the peripheral steel bars.

6. The anchoring device of claim 2, wherein the outside of the tendon bundles is filled with ordinary concrete to form a concrete anchor rod section, and the outside of the tendon bundles is filled with micro-capsule concrete to form a self-healing anchor rod section.

7. The anchoring device of claim 1, wherein the anchor comprises a geomembrane bag arranged on the outer layer, and the geomembrane bag is filled with concrete.

8. An anti-floating lightweight soil subgrade structure comprising an anchoring device according to any one of claims 1 to 7.

9. The anti-floating light soil roadbed structure according to claim 8, further comprising roadbed soil, wherein a thick gravel cushion layer, a light soil layer and a concrete plate are sequentially arranged above the roadbed soil from bottom to top;

the concrete anchor rod section is embedded in the roadbed soil, and the self-healing anchor rod section is embedded in the light soil layer and the concrete slab.

10. The construction method of the anti-floating self-repairing anchoring device as claimed in any one of claims 1 to 7, wherein the construction method comprises the following steps:

drilling by using a hole expanding device, and sleeving the geomembrane bag on the head of the hole expanding device for expanding holes;

moving out the reaming device, inserting the anchor head and the anchor bar bundle which are connected into a whole into the hole, and sleeving a sleeve outside the anchor bar bundle;

grouting, wherein in the grouting process, the sleeve rises along with the grout;

filling common concrete for grouting, and stopping grouting when the common concrete reaches the joint part of the foundation soil and the light soil; filling microcapsule concrete until the microcapsule concrete reaches a concrete slab, and stopping grouting;

and inserting the reinforcing steel bar bundles reserved at the top end of the self-healing anchor rod section into the anchor plate, and performing concrete curing.

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