A fastening anchor device and construction method thereof

Abstract

The present invention provides a fastening type anchor device and a construction method thereof. The anchor device comprises an anchor bolt system and a ring-support type fastening device, wherein the anchor bolt system comprises an anchor bolt, a grouting pipe, an anchor bolt anchor body and an anchor end fixing body, wherein the anchor bolt anchor body is formed by grouting toward the anchor hole through the grouting pipe after the ring-support type fastening device is installed; the ring-support type fastening device comprises a steel strand and a plurality of ring-support mechanisms equidistantly arranged on the anchor bolt, wherein each ring-support mechanism comprises a fixed collar fixedly sleeved outside the anchor bolt, a sliding collar movably sleeved outside the anchor bolt and a plurality of top pressure plates distributed in an annular shape outside the anchor bolt, and the two sides of each top pressure plate are respectively connected to the fixed collar and the sliding collar by connecting strips. The present invention installs the ring-support mechanism on the anchor bolt, and realizes the compression force between the top pressure plate of the ring-support body and the side wall of the borehole by tensioning the ring-support body with the steel strand, thereby increasing the friction between the anchor body and the hole wall, and effectively increasing the anchoring force of the anchor bolt.

Description

Technical Field

[0001] The invention patent relates to the field of anchor support, specifically a fastened anchor device and its construction method used in the field of slope and landslide control, which is suitable for rock and soil slope support and landslide anchor engineering control generated by excavation. Background Art

[0002] Anchor support is a widely used reinforcement support method in geotechnical engineering. It is of great significance in surface engineering such as slopes and deep foundation pits, as well as underground chambers such as tunnels and mining sites. Ordinary mortar anchors are widely used in slope support due to their low cost and simple structure. The construction process includes drilling, hole cleaning, anchor installation, grouting, etc.

[0003] At present, the most widely used type of anchor is the full-length bonded anchor. The full-length bonded anchor is easy and fast to construct. As a rigid body, it uses the friction between the anchor body and the surrounding rock and soil to provide a reaction force for slope stability support. Its disadvantage is that when the slope is deformed, the full-length bonded anchor has a large front end and a small tail end. Especially when the anchor is long, the ultimate friction resistance cannot be exerted simultaneously within the length of the anchor. The pressure dispersion and tension dispersion anchors solve this problem to a certain extent, but the anchoring force limit value provided by the overall anchoring section is fixed and unchanged. Once the slope is deformed or even landslides, the rock and soil layer around the anchor is tensile and sheared, and the strength change of the surrounding rock and soil tends to the residual strength, resulting in a significant reduction in the anchoring force that the anchor can provide, and the fundamental of providing reliable reaction force to maintain slope stability is lost.

[0004] Therefore, in order to change the force distribution characteristics of the anchoring section of the anchor rod during use and to ensure that the anchor body of the anchor rod maintains a high anchoring force when the slope is deformed, the present invention provides a fastening anchor rod device and a construction method thereof. Summary of the invention

[0005] The present invention provides a fastening anchor device and a construction method thereof in order to make the force on the anchoring section of the anchor rod more evenly distributed along the length during use and to ensure that the anchor rod anchor body can provide reliable anchoring force when the slope is deformed. The device is innovatively improved on the basis of the traditional anchor rod structure and construction process, and the friction force of the anchor rod is increased by arranging a ring-supporting fastening structure and pre-tensioned steel strands along the anchor rod, thereby improving the anchoring force of the anchor rod and improving the stability of the slope.

[0006] In order to achieve the above technical purpose, the present invention provides a fastening type anchor device, including an anchor anchoring system, the anchor anchoring system including an anchor, a grouting pipe, an anchor anchor body and an anchor end fixing body, the anchor and the grouting pipe are distributed along the anchor hole, and the ends thereof are fixed outside the hole opening of the anchor hole through the anchor end fixing body, the anchor device also includes a ring-support type fastening device, and the anchor anchor body is formed by grouting toward the anchor hole through the grouting pipe after the ring-support type fastening device is installed;

[0007] The ring-support type fastening device comprises a steel strand and a plurality of ring-support mechanisms equidistantly arranged on the anchor rod, each ring-support mechanism comprising a fixed collar, a sliding collar and a plurality of arc-shaped top pressure plates, the fixed collar is fixedly sleeved outside the anchor rod, the sliding collar is movably sleeved outside the anchor rod, and the fixed collar is close to one side of the anchor end fixed body, a plurality of arc-shaped top pressure plates are distributed in an annular shape on the outside of the anchor rod, and the two sides of each top pressure plate are respectively connected to the fixed collar and the sliding collar by connecting strips; the steel strand is sequentially connected to the sliding collar of each group of ring-support mechanisms and extends along the anchor rod, and its end is longer than the end of the anchor rod, and under the action of the steel strand, the sliding collars of the plurality of ring-support mechanisms are controlled to move simultaneously along the anchor rod toward one side of the anchor end fixed body, and at the same time drive the connecting strip to open the top pressure plates and expand radially toward the ring-support body, thereby applying pressure to the side wall of the anchor hole;

[0008] A diaphragm is fixedly covered on the surface of each group of ring support mechanisms, and corresponding grouting pipe perforations and steel strand perforations are opened on the diaphragm. The grouting pipe and the steel strand pass through the corresponding grouting pipe perforations and steel strand perforations on the diaphragm of each group of ring support mechanisms in sequence. A slurry outlet hole is provided in the area where the grouting pipe is located outside the ring support mechanism. During the grouting process, no slurry is injected into each group of ring support mechanisms.

[0009] A further technical solution of the present invention is as follows: the anchor rod anchoring system also includes a frame center ring and a lattice beam, the anchor rod and the grouting pipe pass through the anchor hole, the frame center ring is used for centering and positioning the anchor rod, the grouting pipe and the steel strand; the ends of the anchor rod and the steel strand are anchored in the lattice beam through anchor end fixing bodies, and the lattice beam is formed by tying the lattice beam steel bars at the ends of the anchor rods to form a template and pouring lattice beam concrete after the anchor rods are installed and grouting is completed, and during the construction of the lattice beam, installation holes for the anchor end fixing bodies are reserved.

[0010] A preferred technical solution of the present invention is that the outer diameter of the annular body composed of a plurality of top pressure plates is smaller than the inner diameter of the anchor hole, and anti-slip grooves are provided on the outer surface of each top pressure plate.

[0011] A more preferred technical solution of the present invention: the top pressure plate and the connecting strip are symmetrically arranged with the anchor rod as the central axis, and a sleeve ring for fixing the connecting strip is provided on the fixed ring, the sliding ring and each top pressure plate, and T-shaped connectors are respectively provided at both ends of the connecting strip, and the sleeve ring includes two symmetrically arranged sleeves, and the two ends of the T-shaped connector of the connecting strip are respectively rotatably connected in the two sleeves of the sleeve ring.

[0012] The preferred technical solution of the present invention is as follows: two steel strands are provided, symmetrically arranged on both sides of the sliding ring, and fixing ears are symmetrically arranged on both sides of the sliding ring of each set of ring support mechanisms, and the steel strands are connected to the fixing ears of the sliding ring; each steel strand is wrapped with a plastic threaded tube on the outside.

[0013] The preferred technical solution of the present invention is as follows: the diaphragm is divided into two parts, which are respectively fixed to cover the outer surfaces of the connecting strips connected to the fixed collar and the sliding collar on both sides of the top pressure sheet, and the circular area of ​​each part of the fixed diaphragm in the opened state is larger than the circular area formed after the connecting strips on both sides of the top pressure sheet are fully unfolded, and completely covers the gap between the fixed collar and the top pressure sheet and the gap between the sliding collar and the top pressure sheet;

[0014] A better technical solution of the present invention: the anchor end fixing body includes a bearing plate, a locking plate and a locking pin, and the bearing plate and the locking plate are both provided with anchor rod fixing holes and steel strand fixing holes. The anchor rod is fixed by the bearing plate and the locking plate, and then the steel strand is pre-tensioned to the design value, and the locking pin is inserted to lock the steel strand.

[0015] In order to achieve the above technical purpose, the present invention also provides a construction method of the above-mentioned fastening anchor device, and the specific construction steps are as follows:

[0016] S1. Determine the number n of ring-support mechanisms required in the ring-support fastening device according to the design value F of the total anchoring force of the anchor rod required for construction. The specific calculation process is as follows:

[0017] Where: F: design value of total anchoring force of anchor rod, kN; n: number of ring support mechanisms;

[0018] f: Friction force between a single ring support mechanism and the side wall of the anchor hole due to the tension of the steel strand, kN;

[0019] f rbk : The ultimate bonding strength between the anchor bolt and the rock and soil layer on the side wall of the anchor hole, kPa;

[0020] L e : Anchor bolt anchor body length, m; k: safety factor, take 2.0; D: anchor hole diameter, m;

[0021] μ: The friction coefficient between the top pressure plate of the ring support mechanism and the side wall of the anchor hole, tanα,

[0022] α: internal friction angle of the side wall rock and soil, °;

[0023] T: preload applied by the strand, kN; N: positive pressure of the top pressure plate of the ring support mechanism on the side wall of the anchor hole, kN;

[0024] θ: The angle between the anchor rod and the connecting strip when the top pressure plate of the ring support mechanism contacts the side wall of the anchor hole, degrees;

[0025] S: axial force of the connecting bar generated by the preload applied by the steel strand, kN;

[0026] S2. The n ring support mechanisms determined in step S1 are installed equidistantly on the anchor rod, the fixed collar of each ring support mechanism is welded and fixed to the anchor rod, the sliding collar slides on the anchor rod, and the fixed collar is located on the side of the fixed body adjacent to the anchor end; a grouting pipe perforation and two steel strand perforations are reserved on the diaphragm of each ring support mechanism;

[0027] S3. Install a frame ring on the anchor rod, a center hole is opened in the middle of the frame ring, and two frame ring side holes and a frame ring grouting pipe hole are opened on the frame ring, and the anchor rod is passed through the center hole of the frame ring. The frame ring is set on the side of the anchor rod adjacent to the anchor rod end fixing body, and the frame ring is set away from the first group of ring support body mechanisms close to the slope surface;

[0028] S4. Install the grouting pipe and two steel strands, which are symmetrically arranged on both sides of the ring support mechanism; the grouting pipe and the steel strands first pass through the frame middle ring, the steel strands pass through the side holes of the frame middle ring, and the grouting pipe passes through the grouting pipe hole of the frame middle ring; then the grouting pipe is sequentially passed through the grouting pipe perforations reserved on the diaphragm of each ring support mechanism, and no grouting holes are provided at the part of the grouting pipe located inside the ring support mechanism, the steel strands are sequentially passed through the steel strand perforations on the diaphragm of each ring support mechanism and fixed to the fixing ears on the side of the sliding sleeve ring of each ring support mechanism, and finally extended to the end of the anchor rod;

[0029] S5. Use a drilling rig to construct an anchor hole, and put the anchor rod equipped with a frame center ring and a ring support type fastening mechanism into the anchor hole. The ends of the anchor rod, steel strand and grouting pipe are all located outside the anchor hole. Use the grouting pipe to inject low pressure grout until the anchor hole is filled with grout. Let it stand for a while. If the grout at the hole sinks, add grout in time until the hole is full of grout.

[0030] S6. After the grout in the anchor hole solidifies, tie the anchor lattice beam reinforcement and prepare a template, and reserve the position of the bearing plate and the locking plate within the lattice beam; then pour the lattice beam concrete, and after the lattice beam concrete solidifies, install the bearing plate and the locking plate, pass the anchor rod through the anchor rod holes on the bearing plate and the locking plate in turn, and pass the two steel strands through the steel strand holes on the bearing plate and the locking plate in turn;

[0031] S7. Finally, use the jack to tension the steel strand to 1.1 to 1.2 times the design locking tension value. Under the tension of the steel strand, multiple sets of ring support mechanisms simultaneously perform axial compression movement to increase the pressure on the top pressure plate and the side wall of the anchor hole. Finally, insert the locking pin, release the jack pressure, and the steel strand automatically pulls back to squeeze the locking pin. The locking pin limits the steel strand to pull back and deform to achieve the effect of storing the internal force of the steel strand. After inserting the locking pin, the anchor end fixed body is sealed with a higher grade of concrete.

[0032] A preferred technical solution of the present invention is as follows: in the step S1, the total anchoring force design value F of the anchor rod is greater than or equal to the total anchoring force demand value that meets the stability requirements of the slope or landslide.

[0033] A more preferred technical solution of the present invention: in the S4 step, grouting holes are provided at the portion of the grouting pipe between the two ring support mechanisms, and a plurality of grouting holes are equidistantly provided in each area. The grouting holes are circular, and the diameter is 1 / 4 to 1 / 3 of the diameter of the grouting pipe; the reserved length of the steel strand end is 1m longer than that of the anchor rod end, and a steel strand threaded tube is sleeved on the portion of the steel strand not fixed to the fixing ear.

[0034] The advantages and beneficial effects of the present invention are:

[0035] (1) By setting up multiple ring-supported fastening structures along the anchor rod, the distribution of the anchoring force of the anchor rod along the length of the rod is changed. By pre-tensioning the steel strands, the friction between the ring-supported fastening structures and the anchor hole is controlled, thereby increasing the friction between the anchor rod and the surrounding strata and the anchoring force of the anchor rod. Under the condition of the same length of anchor rod, the slope stability can be improved.

[0036] (2) The number of the ring-supported fastening structures of the present invention is calculated based on the required anchoring force design value.

[0037] According to the required design value of anchoring force, the number of ring supports and the tensioning force of the steel strands can be reasonably arranged to achieve the predetermined goal of anchoring force control, achieve the best effect with the optimal design scheme, and reduce construction costs.

[0038] (3) When the slope continues to deform during normal operation, the moving slope and the steel strands move in the same direction, which can compress the annular support body. The positive stress between the annular support body top pressure plate and the side wall of the anchor hole is further increased, and the friction force on the annular support body top pressure plate against the side wall of the anchor hole is also increased accordingly. This force is finally transmitted to the lattice beam to inhibit the slope rock and soil from continuing to deform. BRIEF DESCRIPTION OF THE DRAWINGS

[0039] Figure 1 It is a schematic diagram of the overall structure of the present invention;

[0040] Figure 2 It is an enlarged schematic diagram of the connection part between the ring-support type fastening device and the anchor rod in the present invention;

[0041] Figure 3 It is a structural schematic diagram of the ring-support type fastening device in the present invention;

[0042] Figure 4 It is a schematic diagram of the connection between the connecting strip and the sleeve ring in the ring-support type fastening device of the present invention;

[0043] Figure 5 It is a schematic diagram of the steel strand structure in the present invention;

[0044] Figure 6 This is a schematic diagram of the frame-in-ring structure of the present invention;

[0045] Figure 7 It is a schematic diagram of the structure of the load-bearing plate in the present invention;

[0046] Figure 8 It is a schematic diagram of the locking plate structure in the present invention;

[0047] Fig. 9 It is a schematic diagram of the connection between the locking pin, the locking plate and the steel strand in the present invention;

[0048] Fig.10 It is a force diagram of the ring support mechanism in the present invention.

[0049] In the figure: 1—fixing collar, 2—connecting strip, 3—top pressure plate, 3-1—anti-slip groove of top pressure plate, 3-2—diaphragm, 3-3—grouting pipe perforation, 3-4—steel strand perforation, 4—ring support mechanism, 5—sleeve ring, 6—sliding collar, 7—fixing ear, 8—anchor rod, 8-1—grouting pipe, 8-2—slurry outlet hole, 9—steel strand, 9-1—steel strand threaded pipe, 10—center ring, 10-1—side hole of center ring, 10-2—center hole of center ring, 10-3—grouting pipe hole of center ring, 11—bearing plate, 12—locking plate, 13—locking pin, 14—anchor rod anchor body, 15—lattice beam, 16—anchor hole. DETAILED DESCRIPTION

[0050] The present invention will be further described below in conjunction with the accompanying drawings and embodiments. Figures 1 to 9 The drawings are all of embodiments, which are drawn in a simplified manner and are only used for the purpose of clearly and concisely illustrating the embodiments of the present invention. The technical solutions shown in the following drawings are specific solutions of the embodiments of the present invention and are not intended to limit the scope of the invention claimed for protection. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0051] An embodiment provides a fastening anchor device, including an anchor anchoring system and a ring-supporting fastening device, wherein the anchor anchoring system is an existing anchoring system, including an anchor rod 8, a frame center ring 10, an anchor anchor body 14, an anchor end fixing body, a grouting pipe 8-1 and a lattice beam 15; the anchor rod 8 and the grouting pipe 8-1 pass through the anchor hole, and the frame center ring 10 is used for centering the anchor rod 8, the grouting pipe 8-1 and the steel strand 9; the anchor anchor body 14 is an anchor body formed by grouting into the anchor hole through the grouting pipe 8-1 after the ring-supporting fastening device is installed, and the end of the anchor rod 8 is anchored in the lattice beam 15 through the anchor end fixing body, and the anchor end fixing body includes a bearing plate 11, a locking plate 12 and a locking pin 13. The lattice beam 15 is formed by tying the lattice beam 15 steel bars at the ends of the anchor rods 8 to form a template and pouring the lattice beam concrete after the anchor rods are installed and grouting is completed. During the construction of the lattice beam 15, holes for the bearing plate 11 and the locking plate 12 are reserved. After the lattice beam concrete solidifies, the ends of the anchor rods 8 are fixed by the bearing plate 11 and the locking plate 12, and then the steel strands 9 are pre-tensioned to the design value, and the locking pins 13 are inserted to lock the steel strands to form a stable internal force, and the anchor section fixed body is closed with a higher grade of concrete.

[0052] The ring-support type fastening device in the embodiment, such as Figures 1 to 3 As shown, it includes a steel strand 9 and multiple groups of ring support mechanisms 4 equidistantly arranged on the anchor rod 8, each group of ring support mechanisms 4 includes a fixed collar 1, a sliding collar 6 and a plurality of arc-shaped top pressure plates 3, the fixed collar 1 is fixedly sleeved outside the anchor rod 8, the sliding collar 6 is movably sleeved outside the anchor rod 8, and the fixed collar 1 is close to one side of the anchor end fixed body, and a plurality of arc-shaped top pressure plates 3 are distributed in an annular shape on the outside of the anchor rod 8, and the outer diameter of the annular body composed of the multiple top pressure plates 3 is smaller than the inner diameter of the anchor hole 16, and the two sides of each top pressure plate 3 are respectively connected to the fixed collar 1 and the sliding collar 6 through connecting strips 2, the top pressure plates 3 and the connecting strips 2 are both centrally symmetrically arranged, and when the sliding collar 6 slides toward the fixed collar 1, the multiple top pressure plates 3 are simultaneously driven to move radially outward to closely contact the inner wall of the anchor hole 16 and apply positive pressure, and an anti-slip groove 3-1 is arranged on the outer surface of each top pressure plate 3 to increase the friction coefficient between the top pressure plate 3 and the inner wall of the anchor hole. A sleeve ring 5 for fixing the connecting strip 2 is provided on the fixed sleeve ring 1, the sliding sleeve ring 6 and each top pressing plate 3. Figure 4 As shown, T-shaped connectors are respectively provided at both ends of the connecting strip 2, and the sleeve ring 5 includes two symmetrically arranged sleeves, the inner diameter of the inner hole of the sleeve is slightly larger than the diameter of the T-shaped connector of the connecting strip 2, and the two ends of the T-shaped connector of the connecting strip 2 are respectively rotatably connected in the two sleeves of the sleeve ring 5, and the sleeve ring 5 forms a linkage radial extension with the connecting strip 2 and the top pressure plate 3. The T-shaped connector at one end of the connecting strip 2 makes a circumferential swing arm motion in the sleeve ring 5 connected to the sleeve ring, thereby driving the longitudinal connecting strip to swing, and the T-shaped connector at the other end of the connecting head 2 drives the top pressure plate 3 to expand radially toward the annular support body, and the top pressure plate 3 radially extends to squeeze the side wall of the borehole to generate positive stress.

[0053] like Figure 2 As shown, in the embodiment, there are two steel strands 9 in the fastened anchor rod, which are symmetrically arranged on both sides of the sliding collar 6. The sliding collar 6 of each set of ring support mechanisms is symmetrically provided with fixing ears 7. The steel strands 9 are connected to the fixing ears 7 of the sliding collar 6. One side of multiple sets of ring support mechanisms is connected by the same steel strand 9. The steel strand 9 can pass through the fixing ears 7 of each sliding collar 6 and be fixed with the fixing ears 7 before connecting to the next sliding collar 6. It can be achieved that the same steel strand 9 controls the sliding of multiple sliding collars 6 at the same time. The symmetrical arrangement of the two steel strands 9 can ensure uniform force and symmetrical tensile deformation. The surface of the steel strand 9 is wrapped with a plastic threaded tube 9-1, and the other end of the steel strand 9 is connected to the anchor end fixed body, so that when the anchor rod is tensioned, the steel strand 9 transmits the pulling force to the sliding ring 6, controls the sliding ring 6 to move axially along the anchor rod 8, drives the connecting strip 2 and opens the top pressure plate 3 to expand radially toward the annular support body, and the outer surface of the top pressure plate 3 contacts the side wall of the borehole and applies positive pressure, thereby increasing the friction between the top pressure plate and the side wall of the borehole.

[0054] In order to prevent the slurry from entering the ring support mechanism during the grouting process, Figure 3As shown, a diaphragm 3-2 is fixedly covered on the surface of each group of ring support mechanisms, and the diaphragm 3-2 is divided into two parts, which are respectively fixedly covered on the outer surface of the connecting strip 2 connecting the top pressure plate 3 and the fixed ring 1 and the sliding ring 6, and the circular area of ​​each part of the fixed diaphragm 3-2 in the opened state is larger than the circular area formed after the connecting strip 2 is fully unfolded, which can completely cover the gap between the fixed ring 1 and the top pressure plate 3 and the gap between the sliding ring 6 and the top pressure plate 3, thereby preventing cement slurry from entering the interior of the ring support mechanism, and affecting the sliding of the sliding ring 6 along the rod body of the anchor rod after solidification, thereby failing to open the ring support body and linking the top pressure plate to squeeze the hole wall to increase the friction. In order to facilitate the normal penetration of the grouting pipe 8-1 for grouting, a grouting pipe perforation 3-3 with a diameter slightly larger than the outer diameter of the grouting pipe 8-1 is reserved on both fixed diaphragms 3-2. The grouting pipe 8-1 passes through the grouting pipe perforation 3-3 of each set of ring support mechanisms in turn. Grouting holes are distributed on the body of the grouting pipe 8-1. The grouting hole 8-2 is located between the two sets of ring support mechanisms, and the part of the grouting pipe 8-1 located in each set of ring support mechanisms is not provided with a grouting hole. When grouting is performed, it is ensured that grout is injected between the two adjacent sets of ring support mechanisms, and no grout is injected into each set of ring support mechanisms. The anchor rod 8 is tied together with the grouting pipe 8-1, and the grouting pipe is grouted at low pressure until the hole mouth is reversed. In order to facilitate the passage of the steel strand 9, steel strand through holes 3-4 with diameters matching the steel strand 9 are reserved on the two parts of the fixed diaphragms 3-2, and two steel strand through holes 3-4 are reserved on each side of the fixed diaphragm 3-2. The positions of the grouting pipe through holes 3-3 and the steel strand through holes 3-4 correspond to the positions where the grouting pipe 8-1 and the steel strand 9 pass through after the diaphragm is fully opened, which can ensure that the passage of the grouting pipe 8-1 and the steel strand 9 will not affect the opening of the diaphragm.

[0055] The embodiment provides a construction method of a fastened anchor device, and the specific construction steps are as follows:

[0056] S1. Determine the number n of ring-support mechanisms required in the ring-support type fastening device according to the total anchoring force design value F of the anchor rod required for construction. The total anchoring force design value F of the anchor rod is specifically calculated and determined according to the stability requirements of the slope or landslide. First, according to the stability requirements of the slope or landslide (for example, when the safety factor is controlled to be 1.3), a total anchoring force requirement value is calculated according to the existing slope stability calculation method. The total anchoring force requirement value is the anchoring force that the anchor rod needs to provide when reinforcing the slope. It is the anchoring force that can meet the requirements of slope reinforcement. The total anchoring force design value F of the anchor rod is greater than or equal to the total anchoring force requirement value calculated above. When calculating the number of ring-support mechanisms, first calculate according to Fig.10The preload force applied by the steel strands in the stress analysis diagram of the connecting strips of each group of ring supports can calculate the axial force S of the connecting strips generated by the preload force applied by the steel strands, and then calculate the positive pressure N of the top pressure plate of the ring support mechanism on the side wall of the anchor hole, and finally calculate the friction force f between the single ring support mechanism and the side wall of the anchor hole generated by the tension of the steel strands, and finally calculate the number of ring support mechanisms n required to achieve the required design value F of the total anchoring force of the anchor rod. The specific calculation process is as follows:

[0057] Where: F: design value of total anchoring force of anchor rod, kN; n: number of ring support mechanisms;

[0058] f: Friction force between a single ring support mechanism and the side wall of the anchor hole due to the tension of the steel strand, kN;

[0059] f rbk : The ultimate bonding strength between the anchor bolt and the rock and soil layer on the side wall of the anchor hole, kPa;

[0060] L e : Anchor bolt anchor body length, m; k: safety factor, take 2.0; D: anchor hole diameter, m;

[0061] μ: The friction coefficient between the top pressure plate of the ring support mechanism and the side wall of the anchor hole, tanα,

[0062] α: internal friction angle of the side wall rock and soil, °;

[0063] T: preload applied by the strand, kN; N: positive pressure of the top pressure plate of the ring support mechanism on the side wall of the anchor hole, kN;

[0064] θ: The angle between the anchor rod and the connecting strip when the top pressure plate of the ring support mechanism contacts the side wall of the anchor hole, degrees;

[0065] S: axial force of the connecting bar generated by the preload applied by the steel strand, kN;

[0066] S2. Install the n ring-supporting mechanisms determined in step S1 on the anchor rod 8 at equal intervals, the fixed collar 1 of each ring-supporting mechanism is welded and fixed to the anchor rod 8, the sliding collar 6 slides on the anchor rod 8, and the fixed collar 1 is located on the side of the fixed body adjacent to the anchor end; a grouting pipe perforation 3-3 and two steel strand perforations 3-4 are reserved on the diaphragm 3-2 of each ring-supporting mechanism, and the grouting pipe perforation 3-3 and the two steel strand perforations 3-4 are arranged at the position where the grouting pipe 8-1 and the steel strand 9 pass through after the diaphragm is fully opened;

[0067] S3. Install the frame center ring 10 on the anchor rod 8, the frame center ring 10 has a center hole in the middle, and has frame center ring side holes 10-1 and frame center ring grouting pipe holes 10-3 on both sides, and pass the anchor rod 8 through the frame center ring hole 10-2; the frame center ring 10 is set on the side of the anchor rod 8 adjacent to the anchor rod end fixing body, and the frame center ring 10 is set away from the first group of ring support body mechanisms close to the slope surface; control the anchor rod 8 and the steel strand 9 to be in the center of the drilling hole, and send them into the anchor rod drilling hole together with the anchor rod 8 and the steel strand;

[0068] S4. Install the grouting pipe 8-1 and the steel strand 9; the grouting pipe 8-1 and the steel strand 9 first pass through the frame center ring 10, the steel strand passes through the frame center ring side hole 10-1, and the grouting pipe passes through the frame center ring grouting pipe hole 10-3; then the grouting pipe 8-1 is sequentially passed through the grouting pipe perforation 3-3 reserved on each ring support mechanism diaphragm, and the other parts are tied with the same length as the anchor rod 8. The grouting pipe is located between the two ring support mechanisms. There are grouting holes, and each area is equidistantly opened with multiple grouting holes. The grouting holes are circular with a diameter of 1 / 4 to 1 / 3 of the diameter of the grouting pipe; the steel strand 9 passes through the steel strand through holes 3-4 on the diaphragm of each ring support mechanism in turn and is fixed on the fixing ear 7 on the side of the sliding ring 6 of each ring support mechanism, and finally extends to the end of the anchor rod 8. The reserved length of the end of the steel strand 9 is longer than the end of the anchor rod by 1m. The part of the steel strand 9 not fixed on the fixing ear 7 is sleeved with a steel strand threaded tube 9-1; the installation of the steel strand 9 can be directly passed through the hole on the fixing ear 7 and then tied and fixed, and then continue to extend to the next ring support mechanism;

[0069] S5. The anchor hole 16 is constructed by drilling a rig, and the anchor rod equipped with the frame center ring 10 and the ring support type fastening mechanism is sent into the anchor hole 16 together. The ends of the anchor rod 8, the steel strand 9 and the grouting pipe 8-1 are all located outside the orifice of the anchor hole 16. Low-pressure grouting is performed through the grouting pipe 8-1 until the anchor hole 16 is reversed. If the grout at the orifice sinks for a period of time, the grouting is promptly supplemented until the borehole is full of grout;

[0070] S6. After the slurry in the anchor hole 16 solidifies, tie the anchor lattice beam reinforcement and make a template, and reserve the position of the bearing plate 11 and the locking plate 12 within the range of the lattice beam 15; then pour the lattice beam concrete, and after the lattice beam concrete solidifies, install the bearing plate 11 and the locking plate 12, and set anchor holes at the central axis of the bearing plate 11 and the locking plate 12 respectively, and set steel strand holes symmetrically on both sides of the anchor holes; the anchor holes and steel strand holes on the bearing plate 11 and the locking plate 12 are arranged in a corresponding manner and have the same size, and pass the anchor 8 through the anchor holes on the bearing plate 11 and the locking plate 12 in turn, and the two steel strands 9 pass through the steel strand holes on the bearing plate 11 and the locking plate 12 in turn;

[0071] S7. Finally, use a jack to tension the steel strand 9 to 1.1 to 1.2 times the designed locking tension value. The designed locking tension value is the force required for each anchor rod calculated based on the slope stability. The designed locking tension value here is less than the total anchoring force design value F of the anchor rod in step S1. Under the tension of the steel strand 9, multiple groups of ring support mechanisms 4 perform axial compression movement at the same time to increase the pressure on the top pressure plate 3 and the side wall of the anchor hole 16. Finally, insert the locking pin 13, release the jack pressure, and the steel strand 9 automatically pulls back to squeeze the locking pin 13. The locking pin 13 limits the steel strand to pull back and deform to achieve the effect of storing the internal force of the steel strand. After the locking pin 13 is inserted, the anchor end fixed body is closed with a higher grade of concrete.

[0072] The present invention is constructed on a slope. When the slope continues to deform, a sliding surface at a certain distance from the slope surface moves toward the outside and below of the slope relative to the stable rock and soil layer where the ring support body is located. The moving slope body squeezes and drives the slope surface lattice beam to move in the same direction. The fixed end of the anchor rod in the lattice beam pulls the anchor rod and the steel strand to move in the same direction. The top pressure plate of the ring support body is subjected to the friction force of the side wall of the anchor rod borehole, which drives the ring support body to further perform axial compression movement. The positive stress between the top pressure plate of the ring support body and the side wall of the anchor rod borehole is further increased. The friction force of the side wall of the anchor rod borehole on the top pressure plate of the ring support body is also correspondingly increased. The deformation of the rock and soil outside the sliding surface causes the friction force of the side wall of the anchor rod borehole to increase. The increased friction force is transmitted from the anchor rod to the lattice beam. The lattice beam provides a slope surface reaction force, thereby suppressing the continued deformation of the rock and soil between the lattice beam and the sliding surface.

[0073] The present invention improves the traditional anchor rod and construction process, and provides a fastening anchor rod device and construction method, which can improve the anchor rod anchoring force, break through the limit force value provided by the friction resistance of the borehole side wall, and ensure that the anchor rod anchor body can provide reliable anchoring force when the slope is deformed, thereby improving the stability of the slope. The structure involved in the present invention is easy to make, has clear force, is fast to construct, has obvious effect on the treatment of slopes and landslides, and has high engineering application value.

[0074] In summary, the content of the present invention is not limited to the above-mentioned embodiments, and people with insight in the same field can easily propose other embodiments within the technical guiding ideology of the present invention, but such embodiments are all included in the scope of the present invention.

Claims

1. A fastened anchor device, comprising an anchor anchoring system, the anchor anchoring system comprising an anchor (8), a grouting pipe (8-1), an anchor anchor body (14) and an anchor end fixing body, the anchor (8) and the grouting pipe (8-1) being distributed along an anchor hole (16), and the ends of the anchors being fixed outside the opening of the anchor hole (16) by the anchor end fixing body, characterized in that: The anchor rod device also includes a ring-support type fastening device. The anchor rod anchor body (14) is formed by grouting toward the anchor hole (16) through a grouting pipe (8-1) after the ring-support type fastening device is installed. The ring-support type fastening device includes a steel strand (9) and a plurality of ring-support mechanisms (4) equidistantly arranged on the anchor rod (8). Each group of ring-support mechanisms (4) includes a fixed collar (1), a sliding collar (6) and a plurality of arc-shaped top pressure plates (3). The fixed collar (1) is fixedly sleeved outside the anchor rod (8), and the sliding collar (6) is movably sleeved outside the anchor rod (8). The fixed collar (1) is close to one side of the anchor end fixed body. The arc-shaped top pressure plates (3) are distributed in an annular shape on the outside of the anchor rod (8), and the two sides of each top pressure plate (3) are respectively connected to the fixed ring (1) and the sliding ring (6) through the connecting strip (2); the steel strand (9) is sequentially connected to the sliding ring (6) of each group of ring support mechanisms and extends along the anchor rod (8), and its end is longer than the end of the anchor rod (8). Under the action of the steel strand (9), the sliding rings (6) of the multiple groups of ring support mechanisms are controlled to move simultaneously along the anchor rod (8) toward the anchor end fixed body, and at the same time drive the connecting strip (2) to open the top pressure plate (3) to expand radially toward the side wall of the anchor hole, thereby applying pressure to the side wall of the anchor hole (16); A diaphragm (3-2) is fixedly covered on the surface of each group of ring support mechanisms, and grouting pipe perforations (3-3) and steel strand perforations (3-4) are correspondingly provided on the diaphragm (3-2), the grouting pipe (8-1) and the steel strand (9) sequentially pass through the corresponding grouting pipe perforations (3-3) and steel strand perforations (3-4) on the diaphragm (3-2) of each group of ring support mechanisms, a grouting hole is provided in the area of ​​the grouting pipe (8-1) located outside the ring support mechanisms, and during the grouting process, no grout is injected into each group of ring support mechanisms; The top pressure plate (3) and the connecting strip (2) are symmetrically arranged with the anchor rod (8) as the central axis. A sleeve ring (5) for fixing the connecting strip (2) is provided on the fixed collar (1), the sliding collar (6) and each top pressure plate (3). T-shaped connectors are provided at both ends of the connecting strip (2). The sleeve ring (5) includes two symmetrically arranged sleeves. The two ends of the T-shaped connector of the connecting strip (2) are rotatably connected in the two sleeves of the sleeve ring (5). Two steel strands (9) are provided and symmetrically arranged on both sides of the sliding collar (6). Fixed ears (7) are symmetrically arranged on both sides of the sliding collar (6) of each set of ring support mechanisms. The steel strands (9) are connected to the fixed ears (7) of the sliding collar (6). Each steel strand (9) is wrapped with a plastic threaded tube (9-1) on the outside. The anchor end fixing body comprises a bearing plate (11), a locking plate (12) and a locking pin (13); the bearing plate (11) and the locking plate (12) are both provided with an anchor rod fixing hole and a steel strand fixing hole; the anchor rod (8) is fixed by the bearing plate (11) and the locking plate (12); the steel strand (9) is then pre-tensioned to a design value; and the locking pin (13) is inserted to lock the steel strand.

2. A fastening anchor device according to claim 1, characterized in that: The anchor rod anchoring system further comprises a frame center ring (10) and a lattice beam (15); the anchor rod (8) and the grouting pipe (8-1) penetrate the anchor hole; the frame center ring (10) is used for centering and positioning the anchor rod (8), the grouting pipe (8-1) and the steel strand (9); the ends of the anchor rod (8) and the steel strand (9) are anchored in the lattice beam (15) through an anchor end fixing body; the lattice beam (15) is formed by tying the lattice beam (15) steel bars at the ends of the anchor rod (8) after the anchor rod (8) is installed and grouting is completed, a template is prepared, and lattice beam concrete is poured; during the construction process of the lattice beam (15), a hole position for installing the anchor end fixing body is reserved.

3. A fastening anchor device according to claim 1 or 2, characterized in that: The outer diameter of the annular body formed by the plurality of top pressure sheets (3) is smaller than the inner diameter of the anchor hole (16), and an anti-slip groove pattern (3-1) is provided on the outer surface of each top pressure sheet (3).

4. A fastening anchor device according to claim 1 or 2, characterized in that: The diaphragm (3-2) is divided into two parts, which are respectively fixed to cover the outer surfaces of the connecting strips (2) connected to the fixed collar (1) and the sliding collar (6) on both sides of the top pressure plate (3), and the circular area of ​​each part of the diaphragm (3-2) in the open state is larger than the circular area formed when the connecting strips (2) on both sides of the top pressure plate (3) are fully expanded, and completely cover the gap between the fixed collar (1) and the top pressure plate (3) and the gap between the sliding collar (6) and the top pressure plate (3).

5. A construction method for a fastened anchor device according to any one of claims 2 to 4, characterized in that: The specific construction steps are as follows: S1. Determine the number n of ring-support mechanisms required in the ring-support fastening device according to the design value F of the total anchoring force of the anchor rod required for construction. The specific calculation process is as follows: Where: F: design value of total anchoring force of anchor rod, kN; n: number of ring support mechanisms; f: Friction force between a single ring support mechanism and the side wall of the anchor hole due to the tension of the steel strand, kN; f rbk : The ultimate bonding strength between the anchor bolt and the rock and soil layer on the side wall of the anchor hole, kPa; L e : Anchor bolt anchor body length, m; k: safety factor, take 2.0; D: anchor hole diameter, m; μ: The friction coefficient between the top pressure plate of the ring support mechanism and the side wall of the anchor hole, tanα, α: internal friction angle of the side wall rock and soil, °; T: preload applied by the strand, kN; N: positive pressure of the top pressure plate of the ring support mechanism on the side wall of the anchor hole, kN; θ: The angle between the anchor rod and the connecting strip when the top pressure plate of the ring support mechanism contacts the side wall of the anchor hole, degrees; S: axial force of the connecting bar generated by the preload applied by the steel strand, kN; S2. The n ring support mechanisms determined in step S1 are installed equidistantly on the anchor rod, the fixed collar of each ring support mechanism is welded and fixed to the anchor rod, the sliding collar slides on the anchor rod, and the fixed collar is located on the side of the fixed body adjacent to the anchor end; a grouting pipe perforation and two steel strand perforations are reserved on the diaphragm of each ring support mechanism; S3. Install a frame ring on the anchor rod, a center hole is opened in the middle of the frame ring, and two frame ring side holes and a frame ring grouting pipe hole are opened on the frame ring, and the anchor rod is passed through the center hole of the frame ring. The frame ring is set on the side of the anchor rod adjacent to the anchor end fixing body, and the frame ring is set away from the first group of ring support mechanisms close to the slope surface; S4. Install the grouting pipe and two steel strands, which are symmetrically arranged on both sides of the ring support mechanism; the grouting pipe and the steel strands first pass through the frame middle ring, the steel strands pass through the side holes of the frame middle ring, and the grouting pipe passes through the grouting pipe hole of the frame middle ring; then the grouting pipe is sequentially passed through the grouting pipe perforations reserved on the diaphragm of each ring support mechanism, and no grouting holes are provided at the part of the grouting pipe located inside the ring support mechanism, the steel strands are sequentially passed through the steel strand perforations on the diaphragm of each ring support mechanism and fixed to the fixing ears on the side of the sliding sleeve ring of each ring support mechanism, and finally extended to the end of the anchor rod; S5. Use a drilling rig to construct an anchor hole, and put the anchor rod equipped with a frame center ring and a ring-support type fastening device into the anchor hole. The ends of the anchor rod, steel strand and grouting pipe are all located outside the anchor hole. Use the grouting pipe to inject low-pressure grouting until the anchor hole is filled with grout. Let it stand for a while. If the grout at the hole sinks, add grout in time until the anchor hole is full of grout. S6. After the grout in the anchor hole solidifies, tie the lattice beam reinforcement and prepare the template, and reserve the position of the bearing plate and the locking plate within the lattice beam; then pour the lattice beam concrete, and after the lattice beam concrete solidifies, install the bearing plate and the locking plate, pass the anchor rod through the anchor rod fixing holes on the bearing plate and the locking plate in turn, and pass the two steel strands through the steel strand fixing holes on the bearing plate and the locking plate in turn; S7. Finally, use the jack to tension the steel strand to 1.1 to 1.2 times the designed locking tension value. Under the tension of the steel strand, multiple sets of ring support mechanisms simultaneously perform axial compression movement to increase the pressure on the top pressure plate and the side wall of the anchor hole. Finally, insert the locking pin, release the jack pressure, and the steel strand automatically pulls back to squeeze the locking pin. The locking pin limits the steel strand to pull back and deform, achieving the effect of storing the internal force of the steel strand. After inserting the locking pin, the anchor end fixed body is sealed with a higher grade of concrete.

6. The construction method of a fastening anchor device according to claim 5, characterized in that: In step S1, the total anchoring force design value F of the anchor rod is greater than or equal to the total anchoring force demand value that meets the stability requirements of the slope or landslide.

7. The construction method of a fastened anchor device according to claim 5, characterized in that: In step S4, grouting holes are provided at the position of the grouting pipe between the two ring support mechanisms, and multiple grouting holes are equidistantly provided in each area. The grouting holes are circular, and the diameter is 1 / 4 to 1 / 3 of the diameter of the grouting pipe. The reserved length of the steel strand end is 1m longer than the anchor rod end, and the part of the steel strand not fixed on the fixing ear is sleeved with a plastic threaded tube.

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