Variable-rigidity anchor rod and construction method

Abstract

A variable-rigidity anchor rod comprises an anchor rod body and a variable-rigidity support. The variable-stiffness support is located at the top of the anchor rod; the anchor rod comprises anchor rod concrete and anchor rod steel bars; the anchor rod rebars are located at the core of the anchor rod; the variable-rigidity support is provided with a rib penetrating hole; the anchor rod steel bars penetrate through the bar penetrating holes. The device has the advantages of being adjustable in rigidity, free of secondary grouting and the like.

Description

Technical Field

[0001] This invention belongs to the field of geotechnical engineering technology, and specifically relates to a variable stiffness anchor and its construction method. Background Technology

[0002] As structures are buried deeper, they may float due to the influence of groundwater. Anti-buoyancy anchors are an important technical measure to address this issue. However, under the weight of the structure, uneven settlement may occur, causing the top elevations of the anchors to differ, resulting in differential settlement and secondary stresses on the foundation and structure. This has a particularly significant impact on the internal forces of the foundation and may lead to structural insecurity or increased costs. Summary of the Invention

[0003] This invention provides a variable stiffness anchor and a construction method to reduce differential settlement deformation of the anchor.

[0004] To achieve the above objectives, the present invention adopts the following technical solution.

[0005] A variable stiffness anchor bolt includes an anchor bolt and a variable stiffness support; the variable stiffness support is located at the top of the anchor bolt; the anchor bolt includes anchor bolt concrete and anchor bolt reinforcing bars; the anchor bolt reinforcing bars are located in the core of the anchor bolt; the variable stiffness support has through holes; the anchor bolt reinforcing bars pass through the through holes.

[0006] Preferably, the variable stiffness anchor bolt and the variable stiffness support include a cavity, a cavity wall, and a cavity plate; the cavity is surrounded by the cavity wall and the cavity plate.

[0007] Preferably, the variable stiffness anchor rod has a cavity wall made of rubber or plastic; the cavity plate is made of rubber, plastic, or metal; and the cavity wall and cavity plate are integral or fixedly connected.

[0008] Preferably, the variable stiffness anchor has multiple spaced cavities in the variable stiffness support; the through holes are located inside the cavities; and the diameter of the through holes is not less than the diameter of the anchor bar.

[0009] Preferably, the anchor bolt has a variable stiffness and a positioning element; the positioning element is arranged at intervals along the length of the anchor bolt.

[0010] Preferably, the anchor rod is a variable stiffness anchor rod, and there is a leveling layer between the variable stiffness support and the anchor rod; the anchor rod reinforcement is prestressed steel reinforcement and / or non-prestressed steel reinforcement.

[0011] Preferably, a variable stiffness anchor rod is used, with a foundation at the top of the variable stiffness support, and the anchor rod reinforcement extending from the top of the anchor rod concrete and inserted into the foundation.

[0012] Preferably, the variable stiffness anchor rod has its anchoring steel bars coated with anti-corrosion material within the range of the variable stiffness support.

[0013] Preferably, the variable stiffness anchor bolt has a sealing material between the anchor bolt reinforcement and the through hole.

[0014] A construction method for a variable stiffness anchor bolt, comprising the following steps:

[0015] Step 1, Hole Formation: Creating anchor bolt holes;

[0016] Step 2: Insert the anchor rod reinforcement into the anchor hole;

[0017] Step 3: Pour the anchor bolt concrete;

[0018] Step 4: Excavate the soil on the side of the anchor bolt;

[0019] Step 5: Remove the concrete at the top of the anchor rod corresponding to the excavated soil, and excavate to the predetermined position.

[0020] Step 6: Install the variable stiffness support and pass the anchor rod through the through hole;

[0021] Step 7: Fill with backfill material;

[0022] Step 8: Construction of the foundation.

[0023] Compared with the prior art, the present invention has the following features and beneficial effects.

[0024] 1. Use variable stiffness supports at the ends of anchor bolts to reduce differential settlement between the foundation and the structure.

[0025] 2. The variable stiffness support of the anchor bolt does not require secondary concrete pouring, which reduces construction steps and lowers construction difficulty.

[0026] 3. The variable stiffness support for the anchor bolt adopts a support with a cavity, and the stiffness can be adjusted, which can be used for different foundation conditions.

[0027] 4. The variable stiffness support of the anchor rod is equipped with through holes for the reinforcing bars, which can be connected to the foundation and provide tensile bearing capacity.

[0028] 5. The variable stiffness supports for the anchor rods are made of rubber and plastic, which can reduce the horizontal seismic forces at the bottom of the foundation. Attached Figure Description

[0029] The present invention will now be described in further detail with reference to the accompanying drawings.

[0030] Figure 1 Front view of a variable stiffness anchor. Figure 1 .

[0031] Figure 2 Front view of a variable stiffness anchor. Figure 2 .

[0032] Figure 3 Schematic diagram of cross section of variable stiffness support area Figure 1 .

[0033] Figure 4 Schematic diagram of cross section of variable stiffness support area Figure 2 .

[0034] Figure 5 Schematic diagram of cross section of variable stiffness support area Figure 3 .

[0035] Attached diagram labels: A - reinforced concrete anchor rod, B - variable stiffness support, 1 - anchoring concrete, 2 - anchor rod reinforcement, 3 - through-hole, 4 - cavity, 5 - cavity wall, 6 - cavity plate, 7 - sealing material, 8 - leveling layer, 9 - positioning component.

[0036] To better understand the purpose, technical solution, and function of this invention, the invention will be described in further detail below with reference to the accompanying drawings. Here, illustrative embodiments and their descriptions are used to explain the invention, but are not intended to limit the invention.

[0037] In the description of this invention, it should be understood that the terms "comprising / including," "consisting of," or any other variations thereof are intended to cover a non-exclusive inclusion, such that a product, apparatus, process, or method that comprises a list of elements includes not only those elements but may also include, where necessary, other elements not expressly listed, or elements inherent to such a product, apparatus, process, or method. Without further limitation, an element defined by the phrase "comprising / including…" or "consisting of…" does not exclude the presence of additional identical elements in the product, apparatus, process, or method that includes said element.

[0038] In this invention, unless otherwise explicitly specified and limited, the term "fixed connection" should be interpreted broadly, for example, it can refer to a sleeve connection, an lap joint, a weld, a bolted connection, or a combination of the above connections; the terms "installation," "connection," and "linking" should also be interpreted broadly, for example, they can refer to a fixed connection, a detachable connection, or an integral part; they can refer to a direct connection or an indirect connection through an intermediate medium; they can refer to the internal communication of two components or the interaction between two components; the term "continuous reinforcing bar" refers to a reinforcing bar that is continuous without breakage, or a reinforcing bar that is broken but with a fixed connection between the broken reinforcing bars. Those skilled in the art can understand the specific meaning of the above terms in this invention according to the specific circumstances.

[0039] It should also be understood that the terms "upper", "lower", "front", "rear", "left", "right", "top", "bottom", "inner", and "outer" indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are only for the convenience of describing the present invention and simplifying the description, and do not indicate or imply that the device, component or structure referred to must have a specific orientation, be constructed or operated in a specific orientation, and should not be construed as a limitation of the present invention.

[0040] The implementation of the present invention will be described in detail below with reference to the accompanying drawings and preferred embodiments.

[0041] like Figure 1 and Figure 3 As shown, a variable stiffness anchor includes an anchor A and a variable stiffness support B. The variable stiffness support B is located at the top of the anchor A. The anchor A includes anchor concrete 1 and anchor steel bar 2. The anchor steel bar 2 is located in the core of the anchor A. The variable stiffness support B has a through hole 3, through which the anchor steel bar 2.1 passes.

[0042] A variable stiffness support is installed at the top of the anchor bolt. Under the weight of the foundation, this support has low stiffness and can undergo large deformation, thus adjusting or reducing differential settlement of the foundation. The anchor bolt reinforcement 2.1 passes through the reinforcement hole 3 and can be inserted into the foundation. Under the buoyancy of groundwater, the anchor bolt can provide anti-buoyancy force.

[0043] In specific implementation, such as Figure 4 and Figure 3 , Figure 1 As shown, the variable stiffness support B consists of a cavity 4, a cavity wall 5, and a cavity plate 6. The cavity 4 is surrounded by the cavity wall 5 and the cavity plate 6, and the cavity 6 is located outside the anchor reinforcement. After setting the cavity, it is easy to adjust the stiffness of the variable stiffness support, thereby adjusting the differential settlement deformation.

[0044] In practice, the cavity wall 5 is made of rubber or plastic, and the cavity plate 6 can be made of rubber, plastic, or metal. The cavity wall 5 and the cavity plate 6 are integrally molded or connected as one piece. This facilitates manufacturing, provides good durability, and allows for close contact with the anchor rod reinforcement, reducing corrosion of the anchor rod reinforcement.

[0045] In practical implementation, the variable stiffness support B is provided with multiple spaced cavities 4, with reinforcing bar holes 3 located inside the cavities 4. This provides relatively low stiffness. The diameter of the reinforcing bar holes 3 is not less than 2.2 times the diameter of the anchor rod reinforcing bars. The diameter of the anchor rod is not greater than 350mm and not less than 100mm, which is beneficial for providing greater pull-out bearing capacity.

[0046] In practice, the anchor reinforcement is located in the core, which is within 50% of the radius of the circle inside the anchor. Positioning elements 9 are spaced along the length of anchor A to prevent eccentricity of the anchor reinforcement and avoid additional bending moments.

[0047] In specific implementation, such as Figure 2 As shown, a leveling layer 8 is set between the variable stiffness support B and the anchor rod A to facilitate the transmission of force from the support to the anchor rod.

[0048] In practice, the anchor reinforcement 2 is prestressed steel and / or non-prestressed steel. Prestressed reinforcement helps reduce anchor cracks.

[0049] In practice, the anchor bar 2 extends beyond the top of the anchor concrete 1 and inserts into the foundation 9. This provides pull-out resistance to the foundation. The insertion depth is not less than 50% of the anchorage length of the bar.

[0050] In practice, the anchoring steel bar 2 is coated with anti-corrosion material within the range of the variable stiffness support B to improve its anti-corrosion performance.

[0051] For specific implementation, see Figure 5 There is a sealing material 7 between the anchor rod 2 and the through hole 3, which further improves its corrosion resistance and allows for appropriate adjustment of the anchor rod support stiffness. The sealing material can be lime-soil, concrete, cement mortar, cement grout, or cement-soil mixture.

[0052] A construction method for a variable stiffness anchor bolt, comprising the following steps:

[0053] Step 1, Hole Formation: Creating anchor bolt holes;

[0054] Step 2: Insert the anchor rod 2 into the anchor hole;

[0055] Step 3: Pour the anchor bolt concrete 1;

[0056] Step 4: Excavate the soil on the side of the anchor bolt;

[0057] Step 5: Remove the concrete at the top of the anchor rod corresponding to the excavated soil, and excavate to the predetermined position.

[0058] Step 6: Install the variable stiffness support B and pass the anchor rod 2 through the through hole 3;

[0059] Step 7: Fill with backfill material;

[0060] Step 8: Construction of the foundation.

[0061] In practice, a leveling layer can be added between steps five and six as needed.

[0062] The above embodiments only illustrate several implementation methods of this patent, and their descriptions are relatively specific and detailed, but they should not be construed as limiting the scope of this patent. It should be noted that those skilled in the art can make various modifications and improvements without departing from the inventive concept, and these all fall within the protection scope of this invention. Therefore, the protection scope of this patent should be determined by the appended claims.

Claims

1. A variable stiffness anchor bolt, characterized in that: It includes an anchor rod (A) and a variable stiffness support (B); the variable stiffness support (B) is located at the top of the anchor rod (A); the anchor rod (A) includes anchor rod concrete (1) and anchor rod steel bars (2); the anchor rod steel bars (2) are located in the core of the anchor rod (A); the variable stiffness support (B) has a through hole (3); the anchor rod steel bars (2.1) pass through the through hole (3).

2. The variable stiffness anchor bolt according to claim 1, characterized in that: The variable stiffness support (B) includes a cavity (4), a cavity wall (5), and a cavity plate (6); the cavity (4) is surrounded by the cavity wall (5) and the cavity plate (6).

3. The variable stiffness anchor bolt according to claim 2, characterized in that: The cavity wall (5) is made of rubber or plastic; the cavity plate (6) is made of rubber, plastic or metal; the cavity wall (5) and the cavity plate (6) are integral or fixedly connected.

4. The variable stiffness anchor bolt according to claim 2, characterized in that: The variable stiffness support (B) has multiple spaced cavities (4); the reinforcing bar holes (3) are located inside the cavities (4); the diameter of the reinforcing bar holes (3) is not less than the diameter of the anchor rod reinforcing bars (2.2).

5. The variable stiffness anchor bolt according to claim 1, characterized in that: The anchor rod (A) has positioning elements (9); the positioning elements (9) are arranged at intervals along the length of the anchor rod (A).

6. The variable stiffness anchor bolt according to claim 1, characterized in that: There is a leveling layer (8) between the variable stiffness support (B) and the anchor rod (A); the anchor rod reinforcement (2) is prestressed reinforcement and / or non-prestressed reinforcement.

7. The variable stiffness anchor bolt according to claim 1, characterized in that: The variable stiffness support (B) has a foundation (9) at the top, and the anchor rod reinforcement (2) extends out of the top of the anchor rod concrete (1) and is inserted into the foundation (9).

8. The variable stiffness anchor bolt according to claim 1, characterized in that: The anchoring steel bar (2) is coated with anti-corrosion material within the range of the variable stiffness support (B).

9. The variable stiffness anchor bolt according to claim 1, characterized in that: There is a sealing material (7) between the anchor rod (2) and the through hole (3).

10. A construction method for a variable stiffness anchor bolt, characterized in that: The steps are as follows: Step 1, Hole Formation: Creating anchor bolt holes; Step 2: Place the anchor rod reinforcement (2) into the anchor hole; Step 3, pour the anchor bolt concrete (1); Step 4: Excavate the soil on the side of the anchor bolt; Step 5: Remove the concrete at the top of the anchor rod corresponding to the excavated soil, and excavate to the predetermined position. Step 6: Install the variable stiffness support (B) and pass the anchor rod reinforcement (2) through the reinforcement hole (3); Step 7: Fill with backfill material; Step 8: Construction of the foundation.

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