Prestressed anchor rod for controlling heaving floor deformation of tunnel
By introducing a high-toughness special sleeve and spherical anchor into the anchor bolt, combined with the design of a pressure-bearing pad, the problem that existing anchor bolts cannot resist extrusion force and release horizontal stress is solved, thus achieving effective control of tunnel floor bulging deformation and improving construction progress.
Patent Information
- Application Number
- CN202520534869.8
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2025-03-25
- Publication Date
- 2026-01-30
- Estimated Expiration
- 2035-03-25
AI Technical Summary
Existing anchor bolts are unable to effectively resist extrusion forces and release horizontal stresses, making it difficult to control the deformation of the tunnel floor.
The special sleeve and spherical anchor body, made of high-toughness metal, combined with the pressure-bearing plate design, enhance the pull-out resistance of the anchor rod and release horizontal stress through sleeve deformation, thus optimizing the construction structure.
Effectively control tunnel floor deformation, improve construction progress and reduce costs, and avoid the use of reinforced concrete lintels.
Smart Images
Figure CN223854289U_ABST
Abstract
Description
TECHNICAL FIELD
[0001] The utility model relates to a tunnel engineering construction technical field, concretely is a kind of prestressed anchor rod for controlling tunnel bottom drum deformation. BACKGROUND
[0002] Bottom drum deformation is often neglected in tunnel construction, which can cause invert deformation, reduced support stability and damage to the drainage system, and in severe cases, even cause road cracking, bringing great difficulties to the normal operation of the tunnel, so it is necessary to develop a control measure for the construction stage to inhibit the development of tunnel bottom drum deformation.
[0003] Anchor rod is considered as the main means of local support of tunnel, and is also an important method for controlling bottom drum deformation. Tunnel anchor rod is generally divided into system anchor rod in the upper arch area and lock foot anchor rod at the arch foot, which are used to constrain vertical settlement at the arch top and horizontal convergence at the arch waist respectively. These two kinds of anchor rods resist the loosening pressure and extrusion force of rock mass through the anchoring force of the rod body, thereby achieving the effect of reinforcement.
[0004] However, the evolution mechanism of tunnel bottom drum deformation is different from arch top settlement and horizontal convergence. In addition to the extrusion force in the same direction as the anchor rod, the horizontal force perpendicular to the anchor rod is also an important reason for deformation. The anchor rod in the prior art cannot release horizontal stress while resisting extrusion force, which cannot fully meet the needs of controlling tunnel bottom drum deformation. SUMMARY
[0005] The utility model aims at providing a prestressed anchor rod for controlling tunnel bottom drum deformation to solve the problems raised in the background.
[0006] The utility model can achieve the purpose by the following technical scheme.
[0007] A prestressed anchor rod for controlling tunnel bottom drum deformation, the anchor rod comprises an anchor rod body and an anchoring end.
[0008] The anchor rod body comprises a threaded steel bar, a special sleeve made of high-toughness metal and a threaded guide cap. The special sleeve is sleeved on the outer surface of the threaded steel bar, and one end of the special sleeve is fixedly connected with the threaded guide cap.
[0009] The outer surface of the special sleeve is fixedly connected with a spherical anchor body, the diameter of the spherical anchor body is larger than that of the special sleeve, so as to enhance the pull-out resistance of the anchor rod. A first grouting hole is formed in the outer surface of the special sleeve. The spherical anchor body and the first grouting hole are both provided with a plurality of equidistant holes, and the spherical anchor body and the first grouting hole are arranged alternately.
[0010] Preferably, the anchoring end includes a lower pad and an upper pad, both of which are sleeved on the outer surface of the threaded steel bar. Multiple webs are fixedly connected between the lower pad and the upper pad, and the webs are in the shape of an "I" to enhance the connection strength between the lower pad and the upper pad.
[0011] Preferably, the threaded steel bar is threadedly connected to an anchor wedge, and the anchor wedge and the upper pad are in contact.
[0012] Preferably, a one-way valve is installed in the grouting hole to ensure that the grout does not flow back into the special sleeve after it flows out.
[0013] Preferably, a grouting conduit is provided on one side of the threaded steel bar, the grouting conduit and the threaded steel bar are arranged in parallel, and a fixing element is fixedly connected between the grouting conduit and the threaded steel bar.
[0014] Preferably, the lower pad is provided with a plurality of steel nails on the side near the special sleeve, the steel nails being used to fix the lower pad to the rock mass.
[0015] The beneficial effects of this utility model are:
[0016] I. This utility model installs a spherical anchor body in front of the anchor bolt, which increases the frictional resistance between the anchor bolt and the stratum, improves the anchor bolt's ability to resist the extrusion force of the stratum, and enables it to better control the generation of bottom bulging deformation.
[0017] II. This utility model adds a high-toughness special sleeve to the anchor rod, which can deform without brittle failure. The deformation of the sleeve releases the horizontal ground stress, reduces the extrusion force of the surrounding rock, and slows down the occurrence of bottom heave deformation.
[0018] Third, this utility model optimizes the pressure bearing plate by adopting a double-layer design to improve structural strength. The bottom of the lower plate is fixed in the rock mass with steel nails, which can avoid the need to make reinforced concrete waist beams and speed up the construction progress. Attached Figure Description
[0019] To more clearly illustrate the technical solutions in the embodiments of this utility model or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, for those skilled in the art, other drawings can be obtained based on these drawings without creative effort.
[0020] Figure 1 This is a schematic diagram of the overall structure of the prestressed anchor rod in this utility model;
[0021] Figure 2 This is a schematic diagram of the anchoring end in this utility model;
[0022] Figure 3 This is a schematic diagram of the internal structure of the anchor rod in this utility model;
[0023] Figure 4 This is a schematic diagram of the anchor bolt installation in this utility model.
[0024] The attached figures are labeled as follows:
[0025] 1. Threaded guide cap; 2. Grouting hole; 3. Spherical anchor body; 4. Special sleeve; 5. Threaded steel bar; 6. Lower pad; 7. Web plate; 8. Upper pad; 9. Anchor wedge; 10. Steel nail; 11. Grouting conduit; 12. Fixing element; 13. Rock stratum; 14. Concrete; 15. Grouting body. Detailed Implementation
[0026] The technical solutions of the present utility model will be clearly and completely described below with reference to the accompanying drawings of the embodiments. Obviously, the described embodiments are only some embodiments of the present utility model, and not all embodiments. Based on the embodiments of the present utility model, all other embodiments obtained by those skilled in the art without creative effort are within the protection scope of the present utility model.
[0027] like Figure 1 A prestressed anchor rod for controlling the deformation of tunnel floor heave, the anchor rod comprising an anchor rod body and an anchoring end;
[0028] The anchor rod body includes a threaded steel bar 5, a special sleeve 4 made of high-toughness metal and a threaded guide cap 1. The special sleeve is made of high-toughness metal and can deform without brittle failure. It deforms under the action of horizontal stress to achieve the effect of releasing horizontal stress. The special sleeve 4 is sleeved on the outer surface of the threaded steel bar 5, and one end of the special sleeve 4 is fixedly connected to the threaded guide cap 1.
[0029] The outer surface of the special sleeve 4 is fixedly connected to a spherical anchor body 3. The diameter of the spherical anchor body 3 is larger than that of the special sleeve 4, which is used to enhance the pull-out resistance of the anchor rod. The outer surface of the special sleeve 4 is provided with a first grouting hole 2. Multiple spherical anchor bodies 3 and first grouting holes 2 are equidistantly arranged, and the spherical anchor bodies 3 and first grouting holes 2 are staggered.
[0030] like Figure 1 and Figure 2 The anchoring end includes a lower pad 6 and an upper pad 8, both of which are fitted onto the outer surface of the threaded steel bar 5, allowing them to move on the threaded steel bar 5. Multiple web plates 7 are fixedly connected between the lower pad 6 and the upper pad 8. The lower pad 6, the upper pad 8, and the web plates 7 together constitute a bearing pad. The web plates 7 are I-shaped and are used to enhance the connection strength between the lower pad 6 and the upper pad 8, thereby enhancing the pull-out resistance of the anchor rod and improving the anchoring strength.
[0031] As Figure 1 And Figure 2 The threaded steel bar 5 is threadedly connected with an anchor plate wedge 9, the anchor plate wedge 9 is attached to the upper backing plate 8, and the anchor plate wedge 9 can apply pressure to the upper backing plate 8 in the direction of the lower backing plate 6.
[0032] As Figure 1 And Figure 3 A one-way valve is installed in the grouting hole 2, which can ensure that the slurry does not flow back into the special sleeve 4 after flowing out.
[0033] As Figure 1 And Figure 3 The threaded steel bar 5 is provided with a grouting pipe 11 on one side, the grouting pipe 11 and the threaded steel bar 5 are arranged in parallel, and a fixing element 12 is fixedly connected between the grouting pipe 11 and the threaded steel bar 5, so that the grouting pipe 11 can be fixed to one side of the threaded steel bar 5 through the fixing element 12, and external slurry can be injected into the special sleeve 4 through the grouting pipe 11 and then grouted to the outside through the grouting hole 2.
[0034] As Figure 1 And Figure 4 The lower backing plate 6 is provided with a plurality of steel nails 10 on the side close to the special sleeve 4, the steel nails 10 are used for fixing the lower backing plate 6 to the rock mass, after the anchor rod is installed, the lower backing plate 6 is tightly attached to the special sleeve 4, the steel nails 10 are inserted into the concrete 14, the anchor rod is inserted into the rock stratum 13, the concrete 14 and the rock stratum 13 are both components of the tunnel in the prior art, the anchor rod is wrapped by the grouting body 15, and the grouting body 15 is the injected slurry.
[0035] The construction method of the prestressed anchor rod for controlling tunnel floor heave deformation provided by the utility model is as follows:
[0036] (1) The rock stratum 13 of the tunnel inverted arch area is subjected to drainage treatment, and the over-excavated area is backfilled with concrete 14 to ensure that the inverted arch surface is smooth and smooth;
[0037] (2) The anchor rod installation position is determined by measurement and lofting;
[0038] (3) A drilling machine is used to drill a hole at the anchor rod pre-installation position, the drilling diameter needs to be greater than the diameter of the spherical anchor body 3, grouting is performed into the hole during drilling to lubricate the hole wall, and the hole diameter and hole depth are ensured to be not less than the design value by hole sweeping through the drill bit, and the hole residues are cleaned by high-pressure airflow or mud after drilling is completed.
[0039] (4) After drilling is completed, the anchor rod is loaded into the hole, and during the insertion process, it is ensured that the threaded guide cap 1 is inserted to a depth not less than the design depth, and the special sleeve 4 does not produce excessive deflection.
[0040] (5) After the anchor rod is inserted to the designed depth, grouting is performed in the hole through the grouting pipe 11, the grouting pipe 11 is ensured to be smooth in grouting slurry flow and stable in grouting pressure, and grouting is stopped after the grouting slurry overflows.
[0041] (6) After the grouting body 15 forms strength, a cushion plate is installed, the steel nails 10 at the bottom of the lower cushion plate 6 are ensured to be inserted into the concrete 14, the cushion plate is installed after installation of the anchor device and tensioning of the steel bar to apply prestress, and the anchor plate wedge 9 is installed after the prestress is applied.
[0042] (7) The excess part of the threaded steel bar 5 tail end is cut off, and the anchoring end is protected.
[0043] The prestressed anchor rod for controlling tunnel bottom drum deformation provided by the utility model is used for controlling the bottom drum deformation at the tunnel inverted arch, the anchor rod is installed at the tunnel inverted arch part, the weight of the rock body and the anchor rod itself does not need to be borne, therefore the reinforced concrete waist beam is cancelled, the construction progress is accelerated, and the cost is saved.
[0044] The basic principle, main features and advantages of the utility model are shown and described above. The skilled in the art should understand that the utility model is not limited by the above-mentioned embodiments, the above-mentioned embodiments and the description in the specification are only for illustrating the principle of the utility model, the utility model will have various changes and improvements without departing from the spirit and scope of the utility model, and these changes and improvements all fall into the scope of the utility model claimed for protection.
Claims
1. A prestressed anchor for controlling the deformation of a tunnel floor heave, characterised in that, The anchor bolt includes an anchor bolt body and an anchoring end; The anchor rod body includes a threaded steel bar (5), a special sleeve (4) made of high toughness metal and a threaded guide cap (1), wherein the special sleeve (4) is sleeved on the outer surface of the threaded steel bar (5), and one end of the special sleeve (4) is fixedly connected to the threaded guide cap (1). The outer surface of the special sleeve (4) is fixedly connected to a spherical anchor (3). The diameter of the spherical anchor (3) is larger than that of the special sleeve (4) to enhance the pull-out resistance of the anchor rod. The outer surface of the special sleeve (4) is provided with a first grouting hole (2). Multiple spherical anchors (3) and first grouting holes (2) are equidistantly arranged, and the spherical anchors (3) and first grouting holes (2) are staggered.
2. A prestressed anchor for controlling the deformation of tunnel floor heave according to claim 1, characterised in that, The anchoring end includes a lower pad (6) and an upper pad (8). Both the lower pad (6) and the upper pad (8) are sleeved on the outer surface of the threaded steel bar (5). Multiple web plates (7) are fixedly connected between the lower pad (6) and the upper pad (8). The web plates (7) are in the shape of an "I" and are used to improve the connection strength between the lower pad (6) and the upper pad (8).
3. A prestressed anchor for controlling the deformation of floor heave in a tunnel according to claim 2, characterised in that, The threaded steel bar (5) is threadedly connected to an anchor wedge (9), and the anchor wedge (9) and the upper pad (8) are in contact.
4. The prestressed anchor for controlling the deformation of tunnel floor heave according to claim 1, characterized in that, A one-way valve is installed inside the grouting hole (2) to ensure that the grout does not flow back into the special sleeve (4) after it flows out.
5. The prestressed anchor for controlling the deformation of tunnel floor heave according to claim 1, characterized in that, A grouting conduit (11) is provided on one side of the threaded steel bar (5). The grouting conduit (11) and the threaded steel bar (5) are arranged in parallel, and a fixing element (12) is fixedly connected between the grouting conduit (11) and the threaded steel bar (5).
6. A prestressed anchor for controlling the deformation of tunnel floor heave according to claim 2, wherein, The lower pad (6) is provided with a plurality of steel nails (10) on the side near the special sleeve (4), which are used to fix the lower pad (6) to the rock mass.