Anchor rod capable of resisting large deformation caused by side slope shearing and mounting method of anchor rod

Abstract

The anchor rod comprises a free-section rod body, a flexible large-deformation-section rod body and an anchoring-section rod body which are sequentially connected end to end, an anchor head is fixedly arranged on the free-section rod body, and the anchoring-section rod body is used for being fixed in a stable bed rock, so that the end of the anchor rod is fixed; the free section rod body is used for being fixed in a sliding rock mass in a penetrating mode, the flexible large-deformation section rod body is arranged at a shear deformation zone between the sliding rock mass and a stable bed rock, and the flexible large-deformation section rod body is connected with the free section rod body and the anchoring section rod body through limiting tension type hydraulic jacks at the two ends of the flexible large-deformation section rod body. The limited tension type hydraulic jack senses the pressure of hydraulic oil through a pressure sensing valve arranged on the limited tension type hydraulic jack, and a limited pressure value is set. Tension force and shear force can be borne through deformation of the flexible large-deformation section rod body, the performance of the anchor rod is effectively improved, and the tension type hydraulic jack can be limited to ensure that the tension borne by the anchor rod is constant.

Description

Technical Field

[0001] The invention relates to an anchor rod, in particular to an anchor rod for resisting large deformation of slope shearing and an installation method thereof. Background Art

[0002] Anchor support refers to a reinforcement support method used in surface engineering such as slopes, deep rock foundation pits, and underground chambers such as tunnels and stopes. Rods are made of metal, wood, polymer or other materials and driven into pre-drilled holes in the surface rock mass or the rock mass around the chamber. The surrounding rock is combined with the stable rock mass by the special structure of the head and rod body and the tail support plate, or by relying on bonding to produce a suspension effect, a composite beam effect, and a reinforcement effect to achieve the purpose of support.

[0003] Anchor support technology is widely used in slope reinforcement projects due to its advantages such as low cost, good support effect, simple operation and flexible use. However, traditional anchors still have the following defects:

[0004] 1. Traditional anchor rods are only suitable for tensile deformation of slope rock mass, and are difficult to protect against shear deformation of rock mass. If large displacement shear occurs on the slope, the anchor rod body is easily damaged by tensile shear near the shear zone.

[0005] 2. The ultimate tensile length of traditional anchor rods is small, and the tension on the anchor rods cannot be guaranteed to be constant, which can easily lead to failure of the anchor head and breakage of the rod body.

[0006] The information disclosed in this background technology section is only intended to increase the understanding of the overall background of the application, and should not be regarded as acknowledging or suggesting in any form that the information constitutes the prior art already known to ordinary technicians in this field. Summary of the invention

[0007] The purpose of the present invention is to overcome the shortcomings of the prior art that it cannot resist large shear deformation and cannot ensure constant tension on the anchor rod, and to provide an anchor rod that has strong shear resistance and can ensure constant tension on the anchor rod and its installation method.

[0008] To achieve the above objectives, the technical solution of the present invention is:

[0009] An anchor rod for resisting large deformation of slope shearing, comprising a free section rod body, a flexible large deformation section rod body and an anchor section rod body connected end to end in sequence, wherein an anchor head is fixedly arranged on the free section rod body;

[0010] The anchoring section rod body is used to be fixed in the stable bedrock, thereby fixing the end of the anchor rod;

[0011] The free section rod body is used to be fixed in the sliding rock body in a penetrating manner, so as to stabilize the sliding rock body;

[0012] The flexible large deformation section rod body is arranged at the shear deformation zone between the sliding rock mass and the stable bedrock, and the flexible large deformation section rod body is used to bear tensile force and shear force through deformation.

[0013] The flexible large deformation section rod body is an S-shaped curved steel rod structure, and the flexible large deformation section rod body is used for elastic deformation under the action of tensile force and shear force.

[0014] The two ends of the flexible large deformation section rod body are respectively connected with the free section rod body and the anchoring section rod body through an extrusion sleeve.

[0015] A limited tension type hydraulic jack is fixedly provided at both ends of the flexible large deformation section rod body. The flexible large deformation section rod body is fixedly connected to the ends of the free section rod body and the anchoring section rod body through the limited tension type hydraulic jacks at both ends. The limited tension type hydraulic jack is used to bear the tension transmitted by the rod body and keep the tension constant by discharging hydraulic oil;

[0016] The two limited-tension hydraulic jacks are respectively arranged in the sliding rock mass and the stable bedrock.

[0017] The limited tension hydraulic jack includes a jack cylinder, a piston and a pressure-sensitive valve. One end of the jack cylinder is fixedly connected to the end of the free section rod or the anchor section rod. The other end of the jack cylinder is provided with a hydraulic cylinder hole. The piston is arranged in the jack cylinder. The piston is sealed with the inner wall of the jack cylinder. The end of the flexible large deformation section rod passes through the hydraulic cylinder hole and is connected to the piston as an integral structure. A pressure-sensitive valve is arranged on the side wall of the jack cylinder. The inner cavity of the jack cylinder is connected to the outside through the pressure-sensitive valve.

[0018] The pressure-sensing valve is used to sense the pressure of the hydraulic oil and discharge the hydraulic oil after the hydraulic oil pressure reaches a set limit value to ensure that the piston in the cavity is in a constant pressure state.

[0019] The end of the jack cylinder body far from the hydraulic cylinder hole is provided with a connecting rod of an integral structure, and the end of the connecting rod is provided with an extrusion sleeve.

[0020] The flexible large deformation section rod body includes a plurality of S-shaped bends.

[0021] The anchor head includes a tray and a nut. A through hole matching the free section rod body is opened in the middle of the tray. The flexible large deformation section rod body end of the free section rod body is provided with an external thread matching the nut. After the free section rod body passes through the through hole, it is connected to the nut through the thread thereon.

[0022] A method for installing an anchor rod for resisting large deformation of slope shearing, the method comprising the following steps:

[0023] S1, drill anchor holes at the pre-marked position of the surrounding rock, clean the broken rock and soil in the hole, and check the hole quality before proceeding to S2;

[0024] S2. During the drilling process, the position of the shear sliding surface is found and compared with the previous geological survey data to determine the length L1 of the sliding surface from the hole mouth;

[0025] S3, calculate the length of each segment of the anchor rod, the length of the anchoring segment is a known value l b The length of the flexible large deformation section is l a and the length of the free section of the rod l c The calculation formulas are:

[0026]

[0027] In the above formula, K is the pull-out safety factor of the anchor body, N ak is the axial tension of the anchor rod corresponding to the standard combination of actions, D is the diameter of the drill hole, and f rbk is the standard value of the ultimate bonding strength between the anchor rod and the bedrock, l d The length of the anchor end extending out of the slope surface;

[0028] S4, according to the length values ​​of each segment calculated in S3, assembling the free section rod body, the flexible large deformation section rod body and the anchoring section rod body into an integral anchor rod on site;

[0029] S5. Install the complete anchor rod into the borehole, and control the anchor rod to be in the center of the borehole during the installation process;

[0030] S6. Carry out pressure grouting in the drilled hole and install the anchor head.

[0031] The S6 further comprises the following steps:

[0032] After the grouting is completed, the hole is sealed and cured for 15 days. After the curing time is reached, the initial tension is applied to the end of the free section of the rod to make the anchor rod enter the working state. After the predetermined tension is reached, the tray and nut are installed, and concrete is poured on the outer layer to form a concrete protective layer for protection.

[0033] Compared with the prior art, the present invention has the following beneficial effects:

[0034] 1. An anchor rod for resisting large deformation of slope shearing of the present invention comprises a free section rod body, a flexible large deformation section rod body and an anchoring section rod body which are connected end to end in sequence, wherein an anchor head is fixedly arranged on the free section rod body, the anchoring section rod body is used for being fixed in a stable bedrock, thereby fixing the end of the anchor rod, the free section rod body is used for being fixed in a through-type manner in a sliding rock mass, thereby stabilizing the sliding rock mass, and the flexible large deformation section rod body is arranged in the shear deformation zone between the sliding rock mass and the stable bedrock, and is used for bearing tensile force and shear force through deformation, thereby effectively improving the shear resistance of the anchor rod.

[0035] 2. In an anchor rod for resisting large deformation due to shearing of slopes according to the present invention, a flexible large deformation section rod body is connected to a free section rod body and an anchoring section rod body through limited tension type hydraulic jacks at both ends thereof. The limited tension type hydraulic jack senses the hydraulic oil pressure through a pressure sensing valve arranged thereon and is set with a limited pressure value. When the hydraulic oil pressure reaches or exceeds the limited value, the hydraulic oil is gradually discharged to keep the pressure in the cavity in a constant state, thereby ensuring that the tension on the anchor rod is constant.

[0036] 3. In the installation method of an anchor rod for resisting large deformation due to shearing of a slope of the present invention, after drilling the anchor hole, the length of each segment of the anchor rod is calculated by measuring the length L1 of the sliding surface from the hole mouth, and the free section rod body, the flexible large deformation section rod body and the anchoring section rod body are assembled into an integral anchor rod on site, which can ensure that the flexible large deformation section rod body is located in the shear deformation zone, so that the flexible large deformation section rod body can be deformed in accordance with the displacement of the sliding rock mass.

[0037] 4. In the installation method of the anchor rod for resisting large deformation due to shearing of the slope of the present invention, in S6, when the initial tension is applied to the anchor rod after the curing time is reached, the flexible large deformation section rod body only bears the tension transmitted by the free section rod body and the anchoring section rod body. At this time, the piston displacement inside the limited tension hydraulic jack is limited, and the S-shaped bending stretch on the flexible large deformation section rod body is small. After the installation is completed, when the sliding rock displacement causes the rock shear displacement to reach a certain large value, the hydraulic oil inside the limited tension hydraulic jack is gradually exhausted, and the stretching of the flexible large deformation section rod body increases until it is stretched to a smooth shape. Therefore, the design can effectively extend the ultimate tensile length of the anchor rod by limiting the coordination of the tension hydraulic jack and the flexible large deformation section rod body. BRIEF DESCRIPTION OF THE DRAWINGS

[0038] Figure 1 It is a structural schematic diagram of the present invention.

[0039] Figure 2 It is an exploded view of the present invention.

[0040] Figure 3 yes Figure 1 Schematic diagram of the structure of the limited tension hydraulic jack.

[0041] Figure 4 It is a schematic diagram of the working principle of the present invention.

[0042] Figure 5 It is a schematic diagram of the installation of the present invention.

[0043] In the figure: anchor head 1, tray 11, nut 12, free section rod body 2, flexible large deformation section rod body 3, anchoring section rod body 4, limited tension hydraulic jack 5, jack cylinder 51, piston 52, pressure sensing valve 53, hydraulic cylinder hole 54, connecting rod 55, extrusion sleeve 56, sliding rock mass 6, shear deformation zone 7, stable bedrock 8, concrete protective layer 9. DETAILED DESCRIPTION

[0044] The present invention is further described in detail below in conjunction with the accompanying drawings and specific implementation methods.

[0045] The principle of the present invention is described as follows:

[0046] The flexible large deformation section rod body 3 is cast by hot rolling process and can withstand tensile force and shear force. As the tensile force and shear force increase, the bending degree of the steel rod gradually decreases, and the length gradually increases accordingly;

[0047] Since the anchor rod is subjected to a large tensile force in its working state, the connecting rod 55 on the tension-type hydraulic jack 5 is limited to be connected to the free section rod body 2 or the anchor section rod body 4 through an extrusion sleeve 56 .

[0048] Embodiment 1:

[0049] See also Figures 1 to 3, an anchor rod for resisting large deformation of slope shear, comprising a free section rod body 2, a flexible large deformation section rod body 3 and an anchor section rod body 4 which are connected end to end in sequence, wherein an anchor head 1 is fixedly arranged on the free section rod body 2; the free section rod body 2, the flexible large deformation section rod body 3 and the anchor section rod body 4 are all long rod structures; the anchor section rod body 4 is used to be fixed in a stable bedrock 8, thereby fixing the end of the anchor rod; the free section rod body 2 is used to be fixed in a through-type manner in a sliding rock mass 6, thereby stabilizing the sliding rock mass 6; the flexible large deformation section rod body 3 is arranged in a shear deformation zone 7 between the sliding rock mass 6 and the stable bedrock 8, and the flexible large deformation section rod body 3 is used to pass through the variable The flexible large deformation section rod body 3 is an S-shaped bent steel rod structure, and the flexible large deformation section rod body 3 is used to elastically deform under the action of tensile force and shear force; the two ends of the flexible large deformation section rod body 3 are respectively connected to the free section rod body 2 and the anchoring section rod body 4 through an extrusion sleeve 56; both ends of the flexible large deformation section rod body 3 are fixedly provided with a limited tension type hydraulic jack 5, and the flexible large deformation section rod body 3 is fixedly connected to the ends of the free section rod body 2 and the anchoring section rod body 4 through the limited tension type hydraulic jacks 5 at both ends, and the limited tension type hydraulic jacks 5 are used to withstand the transmission of the rod body The tension is generated by the hydraulic oil, and the tension is kept constant by discharging the hydraulic oil; the two limited tension hydraulic jacks 5 are respectively arranged in the sliding rock mass 6 and the stable bedrock 8; the limited tension hydraulic jack 5 includes a jack cylinder 51, a piston 52 and a pressure-sensitive valve 53, one end of the jack cylinder 51 is fixedly connected to the end of the free section rod body 2 or the anchor section rod body 4, and the other end of the jack cylinder 51 is provided with a hydraulic cylinder hole 54, the piston 52 is arranged in the jack cylinder 51, the piston 52 is sealed with the inner wall of the jack cylinder 51, and the end of the flexible large deformation section rod body 3 passes through the hydraulic cylinder hole 54 and is connected to the piston 52 It is an integrated structure, and a pressure-sensing valve 53 is arranged on the side wall of the jack cylinder 51, and the inner cavity of the jack cylinder 51 is connected with the outside through the pressure-sensing valve 53; the pressure-sensing valve 53 is used to sense the hydraulic oil pressure, and discharge the hydraulic oil after the hydraulic oil pressure reaches the set limit value to ensure that the piston in the cavity is in a constant pressure state; the anchor head 1 includes a tray 11 and a nut 12, and a through hole matching the free section rod body 2 is opened in the middle of the tray 11, and an external thread matching the nut 12 is arranged at the end of the flexible large deformation section rod body 3 of the free section rod body 2, and the free section rod body 2 passes through the through hole and is connected to the nut 12 through the thread thereon.

[0050] Embodiment 2:

[0051] The end of the jack cylinder body 51 far from the hydraulic cylinder hole 54 is provided with a connecting rod 55 of an integral structure, and the end of the connecting rod 55 is provided with an extrusion sleeve 56; the flexible large deformation section rod body 3 includes a plurality of S-shaped bends.

[0052] Embodiment 3:

[0053] See also Figure 4 and Figure 5 , a method for installing an anchor rod for resisting large deformation of slope shear, the installation method comprising the following steps:

[0054] S1, drill anchor holes at the pre-marked position of the surrounding rock, clean the broken rock and soil in the hole, and check the hole quality before proceeding to S2;

[0055] S2. During the drilling process, the position of the shear sliding surface is found and compared with the previous geological survey data to determine the length L1 of the sliding surface from the hole mouth;

[0056] S3, calculate the length of each segment of the anchor rod, the length of the anchoring segment rod body 4 is a known value l b The length of the flexible large deformation section rod 3 is l a and the length of the free section rod 2 l c The calculation formulas are:

[0057]

[0058] In the above formula, K is the pull-out safety factor of the anchor body, N ak is the axial tension of the anchor rod corresponding to the standard combination of actions, D is the diameter of the drill hole, and f rbk is the standard value of the ultimate bonding strength between the anchoring section rod 4 and the bedrock, l d The length of the anchor end extending out of the slope surface;

[0059] S4, according to the length values ​​of each segment calculated in S3, assembling the free section rod body 2, the flexible large deformation section rod body 3 and the anchoring section rod body 4 into an integral anchor rod on site;

[0060] S5. Install the complete anchor rod into the borehole, and control the anchor rod to be in the center of the borehole during the installation process;

[0061] S6. Perform pressure grouting in the borehole and install the anchor head 1.

[0062] The S6 further comprises the following steps:

[0063] After the grouting is completed, the hole is sealed and cured for 28 days. After the curing time is reached, an initial tension is applied to the end of the free section rod body 2 to put the anchor into working state. After the predetermined tension is reached, the tray 11 and the nut 12 are installed, and concrete is poured on the outer layer to form a concrete protective layer 9 for protection.

[0064] The above description is only a preferred embodiment of the present invention, and the protection scope of the present invention is not limited to the above embodiment. Any equivalent modifications or changes made by ordinary technicians in this field based on the contents disclosed by the present invention should be included in the protection scope recorded in the claims.

Claims

1. An anchor rod for resisting large deformation of slope shear, characterized by: It comprises a free section rod body (2), a flexible large deformation section rod body (3) and an anchoring section rod body (4) which are connected end to end in sequence, and an anchor head (1) is fixedly arranged on the free section rod body (2); The anchoring section rod body (4) is used to be fixed in the stable bedrock (8), thereby fixing the end of the anchor rod; The free section rod body (2) is used to be fixed in a penetrating manner in the sliding rock mass (6), thereby stabilizing the sliding rock mass (6); The flexible large deformation section rod body (3) is arranged at the shear deformation zone (7) between the sliding rock mass (6) and the stable bedrock (8), and the flexible large deformation section rod body (3) is used to withstand tensile force and shear force through deformation.

2. The anchor rod for resisting large deformation of slope shear according to claim 1, characterized in that: The flexible large deformation section rod body (3) is an S-shaped curved steel rod structure, and the flexible large deformation section rod body (3) is used to elastically deform under the action of tensile force and shear force.

3. The anchor rod for resisting large deformation of slope shear according to claim 1, characterized in that: Both ends of the flexible large deformation section rod body (3) are respectively connected to the free section rod body (2) and the anchoring section rod body (4) via an extrusion sleeve (56).

4. The anchor rod for resisting large deformation of slope shear according to claim 3, characterized in that: A limited tension type hydraulic jack (5) is fixedly provided at both ends of the flexible large deformation section rod body (3); the flexible large deformation section rod body (3) is fixedly connected to the ends of the free section rod body (2) and the anchor section rod body (4) through the limited tension type hydraulic jacks (5) at both ends; the limited tension type hydraulic jack (5) is used to bear the tension transmitted by the rod body and keep the tension constant by discharging hydraulic oil; The two limited tension type hydraulic jacks (5) are respectively arranged in the sliding rock mass (6) and the stable bedrock (8).

5. The anchor rod for resisting large deformation of slope shear according to claim 4, characterized in that: The limited tension hydraulic jack (5) comprises a jack cylinder (51), a piston (52) and a pressure-sensitive valve (53); one end of the jack cylinder (51) is fixedly connected to the end of the free section rod (2) or the anchor section rod (4); the other end of the jack cylinder (51) is provided with a hydraulic cylinder hole (54); the piston (52) is arranged in the jack cylinder (51); the piston (52) and the inner wall of the jack cylinder (51) are sealed and matched; the end of the flexible large deformation section rod (3) passes through the hydraulic cylinder hole (54) and is connected to the piston (52) to form an integrated structure; a pressure-sensitive valve (53) is arranged on the side wall of the jack cylinder (51); the inner cavity of the jack cylinder (51) is connected to the outside through the pressure-sensitive valve (53); The pressure sensing valve (53) is used to sense the pressure of the hydraulic oil and discharge the hydraulic oil after the hydraulic oil pressure reaches a set limit value to ensure that the piston in the cavity is in a constant pressure state.

6. The anchor rod for resisting large deformation of slope shear according to claim 5, characterized in that: A connecting rod (55) of an integral structure is provided at the end of the jack cylinder body (51) distal from the hydraulic cylinder hole (54), and an extrusion sleeve (56) is provided at the end of the connecting rod (55).

7. An anchor rod for resisting large deformation of slope shear according to any one of claims 1 to 6, characterized in that: The flexible large deformation section rod body (3) comprises a plurality of S-shaped bends.

8. The anchor rod for resisting large deformation of slope shear according to claim 1, characterized in that: The anchor head (1) comprises a tray (11) and a nut (12); a through hole matching the free section rod body (2) is provided in the middle of the tray (11); an external thread matching the nut (12) is provided at the end of the flexible large deformation section rod body (3) of the free section rod body (2); and the free section rod body (2) passes through the through hole and is connected to the nut (12) via the thread thereon.

9. A method for installing an anchor rod for resisting large deformation of slope shear according to any one of claims 1 to 8, characterized in that: The installation method comprises the following steps: S1, drill anchor holes at the pre-marked position of the surrounding rock, clean the broken rock and soil in the hole, and check the hole quality before proceeding to S2; S2. During the drilling process, the position of the shear sliding surface is found and compared with the previous geological survey data to determine the length L1 of the sliding surface from the hole mouth; S3, calculate the length of each segment of the anchor rod, the length of the anchoring segment rod body (4) is a known value l b The length of the flexible large deformation section rod (3) is l a and the length of the free section rod (2) l c The calculation formulas are: In the above formula, K is the pull-out safety factor of the anchor body, N ak is the axial tension of the anchor rod corresponding to the standard combination of actions, D is the diameter of the drill hole, and f rbk is the standard value of the ultimate bonding strength between the anchoring section rod (4) and the bedrock, l d The length of the anchor end extending out of the slope surface; S4, according to the length values ​​of each segment calculated in S3, assembling the free section rod body (2), the flexible large deformation section rod body (3) and the anchoring section rod body (4) into an integral anchor rod on site; S5. Install the complete anchor rod into the borehole, and control the anchor rod to be in the center of the borehole during the installation process; S6. Pressure grouting is performed in the borehole and the anchor head (1) is installed.

10. The method for installing an anchor rod for resisting large deformation due to slope shearing according to claim 9, characterized in that: The S6 further comprises the following steps: After the grouting is completed, the hole is sealed and cured (28) days. After the curing time is reached, an initial tension is applied to the end of the free section rod body (2) so that the anchor rod enters a working state. After the predetermined tension is reached, a tray (11) and a nut (12) are installed, and concrete is poured on the outer layer to form a concrete protective layer (9) for protection.

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