A hanging basket type sliding platform for anchoring construction of dangerous rock mass at a cliff and a mounting method thereof

Abstract

A suspended platform and its installation method are disclosed for anchoring unstable rock masses on steep cliffs. The platform includes a suspended platform, a lifting work platform, and a lifting cable system. The suspended platform includes a base plate, side railings, anti-collision tracks, a telescopic support sliding device, detachable anchor legs, a shock absorption device, and a power failure sensor. The lifting cable system includes a winch, cables, and shear anchor piles. The suspended platform is suspended from the free face by the lifting cable system, which is fixed to the ground by the shear anchor piles. The lifting work platform is installed inside the suspended platform to provide a platform for vertical movement. The telescopic support sliding device is used for sliding the suspended platform on the rock wall. The detachable anchor legs are used for connecting or separating the suspended platform from the rock wall. This invention enables timely separation of the suspended platform from the rock mass, mitigates damage to the work platform when the unstable rock mass collapses, and provides a work platform for reinforcing unstable rock masses on steep cliffs with high free faces.

Description

Technical Field

[0001] This invention relates to the field of rock mass anchoring and protection technology, specifically to a suspended basket-type sliding platform and its installation method for rock mass anchoring construction at steep cliffs, suitable for steep wall construction operations with a high free face. Background Technology

[0002] Large-scale rockfalls are one of the major geological hazards in canyon areas. As a global geological hazard, they are characterized by their suddenness, rapid collapse, and high destructive power. Steep rock faces, due to weathering, erosion of structural surfaces, and unloading, tend to detach from the parent rock. Especially under the influence of human activities, heavy rain, and earthquakes, they are prone to sudden instability and collapse, posing a significant threat to construction projects and human property and safety. In the process of selecting railway and highway routes, it is unavoidable to traverse steep cliffs. In engineering projects, multiple methods are often used to reinforce unstable rock masses. Common methods include removing the unstable rock mass and using external protection measures such as active and passive netting and anchor cable reinforcement. However, external reinforcement requires the construction of a construction platform.

[0003] However, in some reservoir areas, the water surface lies beneath the free face of the rock mass in the drawdown zone, making it impossible to construct a construction platform from the bottom up during the remediation process. Furthermore, in a canyon area, the selection of a highway route involved rock walls with elevation differences exceeding 400 meters, making the construction of a bottom-up platform for anchoring and protection engineering highly costly and risky. Therefore, suspended construction platforms became a preferred solution. However, because anchoring and reinforcement projects require various mechanical equipment such as drilling rigs, tensioning devices, and anchoring materials, these machines bear significant loads. The construction process is also lengthy, involves a large working area, and requires effective avoidance techniques in case of collapse of the upper rock mass. This means that conventional suspended equipment cannot adequately meet the actual needs. Summary of the Invention

[0004] To address the shortcomings of existing technologies, this invention provides a suspended platform and its installation method for anchoring dangerous rock masses on steep cliffs, thus meeting the requirements for anchoring operations on steep walls at higher free surfaces.

[0005] The present invention adopts the following technical solution:

[0006] A suspended platform for anchoring dangerous rock masses at steep cliffs, characterized in that it includes: a suspended platform device, a lifting work platform, and a lifting cable system;

[0007] The suspended platform device includes a base plate, side railings, anti-smashing slide rails, telescopic support sliding device, detachable anchor legs, shock absorption device, and power failure sensor. Side railings are welded to the sides of the base plate, and the anti-smashing slide rails connect four side railings. The shock absorption device is installed between the anti-smashing slide rails and the side railings to reduce the impact force of the anti-smashing slide rails on the side railings.

[0008] The telescopic support sliding device includes a rubber tire and a telescopic mechanism connected to the rubber tire. The telescopic mechanism is fixedly connected to the suspended basket device. The telescopic mechanism is used to adjust the length according to the concave and convex shape of the rock wall during the up and down movement of the suspended basket device, so that the rubber tire is supported on the rock wall and the suspended basket device moves smoothly.

[0009] The detachable anchor support leg includes an anchor rod fixed to the rock wall, a sleeve fixed to the base plate, and a magnetic suction device installed inside the sleeve. The outer end of the anchor rod is inserted into the sleeve and contacts the magnetic suction device. The power failure sensor is used to send power on / off commands to the magnetic suction device to connect or disconnect the magnetic suction device from the anchor rod.

[0010] When the anti-collision slide is hit by a collapsing rock, it triggers a power-off sensor to issue a power-off command, causing the magnetic attraction device to separate from the anchor rod, and then causing the inner side of the suspended basket device to separate from the rock mass; the normal force generated by the rock on the anti-collision slide causes the suspended basket device to rotate, thereby creating a gap between the suspended basket device and the rock mass, and the anti-collision slide serves as a slide for the rock to slide down and fall through the gap between the suspended basket device and the rock mass;

[0011] The lifting platform is installed on the suspended basket device, and the suspended basket device serves as the base of the lifting platform. The lifting platform includes a lifting platform and a lifting device that drives the lifting platform to move up and down.

[0012] The lifting cable system includes a winch, a cable, and shear anchors. The shear anchors are fixed to the ground, and the upper end of the cable passes around the shear anchors and is locked to them with a locking buckle. The lower end of the cable is connected to the winch inside the suspended platform. The lifting and lowering of the suspended platform is achieved by the winch winding and unwinding the cable.

[0013] Furthermore, the base plate is a square frame formed by longitudinal and transverse welding of I-beams, and a steel plate is laid on the base plate;

[0014] The side railing is a mesh structure welded from square tubes, and the bottom part is enclosed by iron plates.

[0015] The anti-smashing track is a top plate structure connecting the inner and outer sides of the side guardrail. The outer side of the top plate structure is inclined upward at 45°. The lower part of the top plate structure is a steel plate, and the upper part is a series of intermittently laid round pipes, laid in a downward slope direction.

[0016] The anti-smashing track is connected to the inner and outer sides of the side guardrail by a shock-absorbing device, which includes an inner cylinder and an outer thick spring.

[0017] Furthermore, the telescopic mechanism includes a wheel hub, a connecting shaft, a connecting rod, a hydraulic cylinder, and a manual hydraulic pump; the rubber tire is mounted on the wheel hub; the connecting shaft passes through a hole in the middle of the wheel hub to connect the rubber tire to the wheel hub; the connecting rod includes a U-shaped steel plate and round steel, forming a pulley system with the connecting shaft; the connecting rod is connected to the telescopic rod of the hydraulic cylinder; the hydraulic cylinder is fixed to the upper surface of the base plate; the manual hydraulic pump supplies oil to the hydraulic cylinder; the manual hydraulic pump has a valve for adjusting the return oil volume.

[0018] Furthermore, one end of the anchor rod is horizontally fixed inside the rock mass, and the other end extends to the side guardrail; when installing the anchor rod, a drilling rig is used to drill a hole in the rock wall, and after insertion, grouting is performed for anchoring; one end of the sleeve is fixed to the base plate, and the other end is sleeved on the other end of the anchor rod; the magnetic attraction device is placed inside the sleeve, and after being energized, it generates magnetic force and attracts the end of the anchor rod together;

[0019] There are two power failure sensors. One power failure sensor is installed below the shock absorption device 106 and is triggered by the shock absorption device. The other power failure sensor is installed on the side guardrail and is triggered manually.

[0020] Furthermore, the lifting device includes a T-screw, a T-nut, a reduction gearbox, a motor, and a control handle;

[0021] The lifting platform is a square steel frame welded longitudinally and transversely from I-beams;

[0022] A T-nut is fixed at each of the four corners of the lifting platform;

[0023] A reduction gearbox is fixed at each of the four corners of the base plate; the reduction gearbox is used to reduce the rotational speed of the T-screw.

[0024] The lower end of the gearbox is connected to the motor; the upper output shaft of the gearbox is fixedly connected to the T-screw via a connector; the T-screw is screwed into the T-nut;

[0025] The motor can rotate in both forward and reverse directions; the motor drives the T-shaped screw to rotate, thereby realizing the up and down movement of the lifting platform;

[0026] The control handle is used to start and stop the motor, as well as to adjust the motor's forward and reverse rotation.

[0027] Furthermore, the lifting cable system also includes guide pulleys and positioning pulleys;

[0028] One winch is installed at each of the four corners of the base plate;

[0029] A positioning pulley is installed at each of the four corners of the side guardrail to support the cable and prevent friction against the suspended basket device;

[0030] The guide pulley is fixed to an I-beam; the I-beam is bolted to the ground, so that the guide pulley extends out of the ground to the free surface, which is used to change the direction of the cable from nearly horizontal to nearly vertical;

[0031] The cable is connected to the winch at its lower end via the guide pulley and the positioning pulley, and its upper end is locked by the latch after passing around the shear anchor pile, thereby realizing the connection between the cable and the shear anchor pile;

[0032] The winch enables the overall vertical movement of the suspended platform by winding and unwinding the cable.

[0033] The shear anchor pile uses its own shear resistance to provide tension for the cable; the shear anchor pile is drilled in the ground rock mass, then a steel pipe is inserted, and finally backfilled with cement grout.

[0034] Furthermore, the design method for the spacing and length of the shear anchor piles includes two cases: the top view of the rock wall is an arc-shaped edge and a linear edge; the arc-shaped edge means that the rock mass on both sides of the shear anchor pile in the y direction is in a free state and is not constrained by the external surrounding rock; the linear edge means that the shear anchor pile is constrained by the surrounding rock extending far to both sides in the y direction.

[0035] The design of the spacing and length of the shear anchor piles requires calculations of rock mass overturning resistance and sliding resistance. The design should be based on the critical state of the rock mass when it is about to overturn or slide, and the overturning resistance and sliding resistance should be satisfied simultaneously.

[0036] The rock mass collapse and failure process is divided into three stages: Stage I, Stage II, and Stage III;

[0037] Stage I is the initial development stage. In the anti-tipping calculation, at this stage, only the ground rock mass on the vertical plane (n0, n1, n2) first experiences tensile failure, while the horizontal plane (m) of the rock mass is ignored. A m B The normal distributed force σ generated on ) m In the anti-sliding calculation: the rock mass is subjected to a normal distributed force σ generated on the vertical plane (n0, n1, n2) due to its own tensile properties. l The shear force τ at the horizontal plane where the bottom of the pile is located m ;

[0038] Stage II is the intermediate toppling stage. In the toppling resistance calculation, at this time, the rock mass has already undergone tensile failure on the vertical planes (n0, n1, n2), and no longer generates a normal distributed force σ on the toppling rock mass. m Only on the horizontal plane of the rock mass (m) A m B A normal distributed force σ is generated on the surface. m In the anti-sliding calculation: the rock mass is only affected by the horizontal plane where the bottom end of the pile is located (m). A m B The shear force τ m ;

[0039] Stage III is the final toppling stage. In the toppling resistance calculation, at this time the rock mass is in both the vertical plane (n0, n1, n2) and the horizontal plane (m). A m B The values ​​above have all exceeded the tensile strength σ of the rock mass. l,max It undergoes tensile failure and no longer generates a normal distributed force σ on the toppled rock mass. l and σ m Only the weight of the rock mass is used to resist the toppling; in the anti-sliding calculation: since both the vertical and horizontal planes are cracked, it is no longer necessary to perform anti-sliding calculations;

[0040] The toppling instability of the rock mass depends on the bending moment at the free face of the rock mass and the horizontal plane at the bottom of the anchor pile (m). A m B The relationship between the sliding force and the instability critical value.

[0041] Furthermore, in the case of the arc-shaped edge, the spacing and length of the shear anchor piles are determined by calculation based on the bending moment of the rock mass at the free face of the edge and the sliding force and instability critical value of the bottom horizontal plane of the anchor piles.

[0042] S1: Calculation process for the overturning resistance of two shear anchor piles A:

[0043] Normal force σ (vertical plane: σ) l Horizontal plane: σ m The bending moment M generated by the weight of the rock mass G on the free surface σ and M G The sum must be greater than the bending moment M generated by the tension F. F :

[0044] M σ +M G >M F

[0045] S2: Calculation process for anti-slip of two shear anchor piles A:

[0046] The normal force σ distributed on the vertical plane (n0, n1, n2) due to the tensile properties of the rock mass itself lCalculated tension F l,σ and the horizontal plane where the bottom of the pile is located (m) A m B The shear stress τ m That is, shear force F m,τ The sum of these forces is greater than the horizontal force F generated by the cable tension.

[0047] F l,σ +F m,τ >2F

[0048] S3: The calculations in stage I must satisfy:

[0049]

[0050] in:

[0051]

[0052] σ0=(G+4F) / S m ;

[0053] S4: The calculation for stage II is as follows:

[0054]

[0055] S5: The calculation for stage III is as follows:

[0056]

[0057] In the formula, l is the pile length; m A Let n be the distance between pile A and the free face; n0 be the distance between the two piles in the y direction; n1 and n2 be the distances between the two piles in the y direction and the free faces on both sides, respectively; S l =l(n0+n1+n2) is the area of ​​the vertical plane (n0, n1, n2); σ l,max This represents the tensile strength of the rock mass; according to the theory of mechanics of materials, the triangular distributed force is converted into a concentrated force at 2 / 3 of the triangle, therefore... The maximum normal force provided by the tensile strength of the rock mass before cracking on the vertical plane (n0, n1, n2) is given by the rock mass. This represents the calculated concentrated force and vertical distance from the free surface. 2F is the horizontal distance between the center of gravity of the rock mass and the free face; 2F is the tension of the two cables; S m =m(n0+n1+n2) is the horizontal plane (m A m B The area of ​​) The maximum normal force provided by the tensile properties of the rock mass on the horizontal plane for the toppling rock mass after the rock mass cracks on the vertical plane and before it cracks on the horizontal plane at the bottom; σ0 is the vertical distance between the converted concentrated force and the free face; σ0 is the normal force generated on the horizontal plane by the weight of the rock mass and the tension of the four cables. c is the friction angle of the rock mass; c is the cohesion of the rock mass.

[0058] In the design process of the shear anchor pile spacing and pile length, parameter m A The selection of values ​​for l is considered to be in the safest state when it meets the calculation formula of stage I, and at the very least, it must meet the calculation formula of stage III; otherwise, the rock mass will experience toppling or sliding failure. Among them, the parameters n0, n1, and n2 are determined based on the conditions of the rock wall edge.

[0059] In the calculation of the two shear anchor piles B far from the free face, based on A, m A Replace with m B That's all, m B Let m be the distance between pile group B and the free face; under the condition that shear anchor pile A satisfies the condition, as long as m B ≥m A Shear anchor pile B will naturally meet the requirements.

[0060] Furthermore, in the linear edge case, the spacing and length of the shear anchor piles are determined by calculation based on the bending moment of the rock mass at the edge free face and the sliding force and instability critical value of the bottom horizontal plane of the anchor pile:

[0061] When the rock mass edge is a linear edge, the overturned rock mass does not overturn along the vertical plane as a whole, including the rock mass on both sides, but only the rock mass within the influence range of the shear anchor piles. According to the elasticity mechanics, the influence range of the hole excavation is 3 to 5 times the hole diameter. For safety considerations, the influence range of the shear anchor piles on both sides is taken as 3n0.

[0062] S1: Calculation process for the overturning resistance of two shear anchor piles A:

[0063] Normal force σ (vertical plane: σ) l Horizontal plane: σ m The bending moment M generated by the weight of the rock mass G on the free surface σ and M G The sum must be greater than the bending moment M generated by the tension F. F :

[0064] M σ +M G >M F

[0065] S2: Calculation process for anti-slip of two shear anchor piles A:

[0066] The normal force σ distributed on the vertical plane (n0, n1, n2) due to the tensile properties of the rock mass itself l (Calculate the tension F)l,σ ) and the horizontal plane where the bottom of the pile is located (m A m B The shear stress τ m (Calculate the shear force F) m,τ The sum of these forces is greater than the horizontal force F generated by the cable tension F:

[0067] F l,σ +F m,τ >2F

[0068] From the shear anchor pile to the outside of the influence range, the normal force generated by the tensile properties of the rock mass gradually decreases to both sides, which can be simplified as a linear decrease;

[0069] S3: The calculation for stage I is as follows:

[0070]

[0071] in:

[0072]

[0073] σ0=(G+4F) / S m ;

[0074] S4: The calculation for stage II is as follows:

[0075]

[0076] S5: The calculation for stage III is as follows:

[0077]

[0078] In the formula, l is the pile length; m A Let n be the distance between pile A and the free face; n0 be the distance between the two piles in the y direction; n1 and n2 be the distances between the two piles in the y direction and the free faces on both sides, respectively; S l,n0 =ln0 and 2·S l,3n0 =6·ln0, where 6 represents the area of ​​the middle region and the two side regions of the vertical plane, respectively; This is the normal force generated on the vertical plane over the area of ​​both sides. Since the loads on both sides are triangularly distributed in both the vertical and horizontal directions, it needs to be multiplied by 1 / 2 twice. The normal force generated on the vertical plane by the area of ​​the intermediate region; It is the sum of the normal forces on the vertical plane; σ l,max The tensile strength of the rock mass is given; according to the theory of mechanics of materials, the triangular distributed force is converted into a concentrated force at 2 / 3 of the triangle. This represents the vertical distance between the converted concentrated force and the free surface. 2F is the horizontal distance between the center of gravity and the free surface; 2F is the tension of the two cables. The normal force generated on the bottom horizontal plane by the area of ​​both sides; The normal force generated by the area of ​​the middle region on the bottom horizontal plane; σ0 is the sum of the normal forces on the horizontal plane; σ0 is the normal force generated on the horizontal plane by the weight of the rock mass and the tension of the four cables. c is the friction angle of the rock mass; c is the cohesion of the rock mass.

[0079] In the design process of the shear anchor pile spacing and pile length, parameter m A The selection of values ​​for l is considered to be in the safest state when the calculation formula of stage I is met, and at the very least, the calculation formula of stage III must be met; otherwise, the rock mass will collapse and fail. Among them, the parameters n0, n1, and n2 are determined based on the conditions of the rock wall edge.

[0080] In the calculation of the two shear anchor piles B far from the free face, based on A, m A Replace with m B That's all, m B Let m be the distance between pile group B and the free face; under the condition that shear anchor pile A satisfies the condition, as long as m B ≥m A Shear anchor pile B will naturally meet the requirements.

[0081] An installation method for a suspended platform used for anchoring unstable rock masses at steep cliffs, as described above, includes the following steps:

[0082] (1) Design the spacing and length of the shear anchor piles according to the calculation method: Drill holes in the ground rock mass, insert steel pipe piles, backfill with cement grout, and install cables to withstand shear force after the strength is sufficient; install guide pulleys on the ground and extend them to the free surface;

[0083] (2) The suspended platform device is welded on site using I-beams, square tubes, and steel plates: First, the base plate is welded, and steel plates are laid on the frame; then the side railings are welded, and steel plates are closed at the bottom of the side railings; then the shock-absorbing device is installed on the side railings; then the anti-smashing slide is welded, with steel plates at the bottom and round pipes laid at intervals on the top, and the laying direction is downward along the slope; finally, the anti-smashing slide is installed above the shock-absorbing device; during the welding process, the following installation holes are reserved: winch, lifting worktable gearbox, telescopic support sliding device, and separable anchor legs;

[0084] (3) The frame of the welding lifting platform: I-beams are welded longitudinally and transversely to form a square steel frame, and a T-nut is fixed at each of the four corners;

[0085] (4) Install the lifting platform: Install the gearbox, motor and T-bolt of the lifting platform at the four corners of the bottom plate of the suspended platform. Align the T-bolt with the T-nut of the lifting platform. Drive the T-bolt to rotate into the T-nut by the motor to complete the installation of the lifting platform.

[0086] (5) Install telescopic support sliding device: Install the hydraulic cylinders of the two telescopic support sliding devices at the two ends of the bottom plate of the suspended platform device, connect the rubber tires, wheel hubs, connecting shafts, connecting rods to the hydraulic cylinders, and fix the manual hydraulic pump to the bottom plate of the suspended platform device;

[0087] (6) Install the lifting cable system: Install the winch of the lifting cable system at the four corners of the bottom plate of the suspended platform, fix the positioning pulley above the side guardrail, and lock the cable on the winch after wrapping it around the positioning pulley and anchoring it once.

[0088] (7) Lifting the overall suspended platform: Use a truck crane to lift the overall suspended platform from the ground to the open surface. During this process, put the cable into the guide pulley groove. After lifting to a certain height, operate the hydraulic cylinder of the telescopic support sliding device so that the rubber tires are supported on the rock wall and the suspended platform can slowly slide down the rock wall.

[0089] (8) Adjust the horizontal state of the suspended platform by using the winch, and gradually loosen the cable of the truck crane so that the suspended platform can start to slide down to the designated working position by the winch itself.

[0090] (9) Drill holes on the rock wall at a position higher than the bottom plate of the suspended platform, install anchor rods, and carry out grouting; install sleeves on the side guardrails and install magnetic suction devices inside the sleeves to attract the anchor rods, so that the suspended platform and the rock mass become one, and prevent the suspended platform from shaking in the direction perpendicular to the rock wall during construction.

[0091] (10) The installation process of the basket-type sliding platform for anchoring dangerous rock masses at steep cliffs can be realized by following steps (1) to (9).

[0092] The present invention has the following beneficial effects:

[0093] 1. The anti-collision sliding track designed in this device, combined with detachable anchor legs, can realize the timely separation of the suspended platform from the rock mass, effectively reducing the damage to the working platform and personnel when the upper dangerous rock mass collapses and becomes unstable during construction.

[0094] 2. The device is equipped with an internal lifting platform that can move within the overall elevation range of the suspended platform and also move flexibly up and down within a small range inside the suspended platform, providing convenience for construction operations;

[0095] 3. The device uses shear anchor piles to provide tension for the cable, making full use of the overturning resistance of the large rock mass on the ground and providing a large bearing capacity for the suspended platform;

[0096] 4. The device adopts a telescopic support sliding device, which can adjust the length of the outriggers according to the concave and convex shape of the rock wall during the up and down movement of the suspended platform, thereby improving the adaptability to uneven wall surfaces and enhancing the stability of the overall suspended platform.

[0097] 5. The device uses anchor bolts as temporary support legs, which can effectively restrain the horizontal displacement of the entire suspended platform and improve its anti-sway capability.

[0098] 6. This invention provides a design method for the spacing and length of shear anchor piles, and gives the judgment criteria and calculation method for rock mass toppling instability, namely the relationship between the bending moment of the rock mass at the edge curve and the sliding force of the horizontal plane at the bottom of the anchor pile and the critical value of instability. Attached Figure Description

[0099] To more clearly illustrate the technical solutions in the embodiments of the present invention, the accompanying drawings used in the description of the embodiments will be briefly introduced below. Obviously, the accompanying drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0100] Figure 1 This is a schematic diagram of the system architecture of the suspended platform for anchoring dangerous rock masses at steep cliffs, according to an embodiment of the present invention.

[0101] Figure 2 This is a schematic diagram of the overall structure of the suspended platform device in an embodiment of the present invention;

[0102] Figure 3 This is a schematic diagram of the lifting worktable in an embodiment of the present invention;

[0103] Figure 4 This is a schematic diagram of the lifting cable system in an embodiment of the present invention;

[0104] Figure 5 This is a schematic diagram of the detachable anchor support leg in an embodiment of the present invention;

[0105] Figure 6 This is a schematic diagram of the telescopic support sliding device in an embodiment of the present invention;

[0106] Figure 7 This is a schematic diagram of the planar arrangement of shear anchor piles in an embodiment of the present invention;

[0107] Figure 8This is a schematic diagram of the rock mass toppling process in an embodiment of the present invention, wherein (a) is stage I, (b) is stage II, and (c) is stage III;

[0108] Figure 9 This is a schematic diagram of the arrangement of shear anchor piles in the case of arc-shaped edges in an embodiment of the present invention, wherein (a) is a front view and (b) is a top view;

[0109] Figure 10 This is a schematic diagram of the rock mass after stage I in the case of arc-shaped edge in an embodiment of the present invention, wherein (a) is a front view and (b) is a top view;

[0110] Figure 11 This is a schematic diagram of the arrangement of shear anchor piles in the case of linear edge in an embodiment of the present invention, wherein (a) is a front view and (b) is a top view;

[0111] Figure 12 This is a schematic diagram of the rock mass after stage I in the case of linear edge in an embodiment of the present invention, wherein (a) is a front view and (b) is a top view;

[0112] Figure 13 This is a schematic diagram of the rock mass under stress during anti-tipping calculation in an embodiment of the present invention, wherein (a) shows the stress distribution of the horizontal and vertical planes in the x direction, (b) shows the stress distribution of the horizontal plane in the y direction in the case of an arc-shaped edge, and (c) shows the stress distribution of the horizontal plane in the y direction in the case of a linear edge.

[0113] Figure 14 This is a schematic diagram of the rock mass under stress during anti-slip calculation in an embodiment of the present invention. (a) shows the stress distribution of the horizontal and vertical planes in the x direction, (b) shows the stress distribution of the horizontal plane in the y direction in the case of an arc-shaped edge, and (c) shows the stress distribution of the horizontal plane in the y direction in the case of a linear edge.

[0114] Wherein: 1—suspended basket device; 2—lifting work platform; 3—lifting cable system;

[0115] 101—Base plate; 102—Side railing; 103—Anti-smashing track; 104—Separable anchor support leg; 105—Telescopic support sliding device; 106—Shock absorption device; 107—Power failure sensor;

[0116] 201—Lifting platform; 202—T-screw; 203—T-nut; 204—Gearbox; 205—Motor; 206—Control handle;

[0117] 301—Winder; 302—Cable; 303—Positioning pulley; 304—Guide pulley; 305—Shear anchor pile; 306—I-beam; 307—Lock;

[0118] 401—Cement grout; 402—Anchor bolt; 403—Sleeve; 404—Magnetic suction device;

[0119] 501—Rubber tire; 502—Wheel hub; 503—Connecting shaft; 504—Connecting rod; 505—Telescopic rod; 506—Cylinder block; 507—Bracket; 508—Manual hydraulic pump. Detailed Implementation

[0120] To make the technical problems, technical solutions, and advantages of this invention clearer, the technical solutions in the embodiments of this invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this invention, and not all embodiments. Based on the embodiments of this invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of this invention.

[0121] like Figure 1 As shown, this embodiment of the invention provides a suspended platform for anchoring dangerous rock masses at steep cliffs, including a suspended platform device 1, a lifting work platform 2, and a lifting cable system 3.

[0122] The upper end of the lifting cable system 3 is anchored to the ground by shear anchor piles 305, and the lower end is fixed inside the suspended basket device 1. The suspended basket device 1 is suspended to the rock wall by cable 302. The lifting basket device 1 can be moved up and down by winch 301 to wind up and down cable 302. The lifting work platform 2 is fixed inside the suspended basket device 1. The lifting platform 201 can be moved up and down within a small range inside the suspended basket device 1 by rotating T-screw 202.

[0123] like Figure 2 As shown, the overall structure of the suspended platform device 1 includes a base plate 101, side guardrails 102, anti-smashing slide rails 103, detachable anchor legs 104, telescopic support sliding device 105, shock absorption device 106, and power failure sensor 107.

[0124] The base plate 101, side railings 102, and anti-collision slide 103 form a rigid frame; the base plate 101 serves as the foundation, with side railings 102 welded to the sides; the anti-collision slide 103 connects four side railings 102; a shock-absorbing device 106 is installed between the anti-collision slide 103 and the side railings 102 to reduce the impact force of the anti-collision slide 103 on the side railings 102; a power failure sensor 107 is installed below the shock-absorbing device 106 near the rock wall to send a demagnetization command to the magnetic attraction device 404; telescopic support. In the sliding device 105, the support 507 of the cylinder 506 is fixed to the base plate 101, and the rubber tire 501 is supported on the rock wall to ensure the stable movement of the suspended platform device 1. It can be extended and retracted by the manual hydraulic pump 508 to adapt to the concave and convex surfaces of the rock wall. In the separable anchor support leg 104, one end of the anchor rod 402 is poured into the mortar of the drilled hole in the rock wall, and the other end is inserted into the sleeve 403 on the side guardrail 102. The anchor rod 402 and the suspended platform device 1 can be separated and joined by the de-energization and energization of the magnetic attraction device 404 in the sleeve 403.

[0125] The anti-smashing slide 103 is a top plate structure connecting the inner and outer sides of the side guardrail 102; the outer side of the top plate structure is inclined upward at 45°; the lower part of the top plate structure is a 10mm thick steel plate, and the upper part is a 50mm diameter round pipe laid at 300mm intervals, with the laying direction along the slope downward.

[0126] The anti-collision slide 103 is connected to the side guardrail 102 by a shock-absorbing device 106; the shock-absorbing device 106 is used to buffer when the dangerous rock collapses and falls onto the anti-collision slide 103, reducing the impact on the side guardrail 102; the shock-absorbing device 106 includes an inner cylinder and an outer thick spring.

[0127] Figure 3 As shown, the structure of the lifting worktable 2 includes a lifting platform 201, a T-screw 202, a T-nut 203, a reduction gearbox 204, a motor 205, and a control handle 206.

[0128] The gearbox 204 is fixed below the four corners of the base plate 101, and the motor 205 is fixed below the gearbox 204. The T-screw 202 is connected to the output shaft of the gearbox 204 to form a rotating device driven by the motor 205. The T-nut 203 is fixed at the four corners of the lifting platform 201. The T-screw 202 passes through the T-nut 203 to connect with the lifting platform 201. The motor 205 can rotate forward and reverse. The rotation of the T-screw 202 driven by the motor 205 realizes the up and down movement of the lifting platform 201. The control handle 206 is arranged inside the basket device 1 to control the forward and reverse rotation of the motor 205 to achieve the purpose of the up and down movement of the lifting platform 201.

[0129] like Figure 4The diagram shows the structure of the lifting cable system 3, which includes a winch 301, a cable 302, a positioning pulley 303, a guide pulley 304, a shear anchor pile 305, an I-beam 306, and a locking buckle 307.

[0130] Shear anchor piles 305 are fixed to the ground. The upper end of the cable 302 passes around the shear anchor piles 305 and is locked to the shear anchor piles 305 by a locking buckle 307. The lower end of the cable 302 is connected to the winch 301 inside the suspended platform device 1. Four positioning pulleys 303 are respectively installed at the four corners of the side guardrail 102 to constrain the position of the cable 302 and prevent friction against the suspended platform device 1. Guide pulleys 304 are installed on the I-beam 306, which is horizontally anchored to the ground and extends out of the rock wall to change the direction of the cable 302. The lower end of the cable 302 is connected to the winch 301 through the lower ends of the guide pulleys 304 and the positioning pulleys 303. The up and down movement of the suspended platform device 1 is achieved by the winch 301 winding and unwinding the cable 302.

[0131] like Figure 5 As shown, the structure of the detachable anchor support leg 104 includes cement grout 401, anchor rod 402, sleeve 403 and magnetic attraction device 404.

[0132] One end of the anchor bolt 402 is horizontally inserted into the drilled hole in the rock wall and anchored using cement grout 401. The other end extends to the side guardrail 102. The magnetic suction device 404 is installed inside the sleeve 403. One end of the sleeve 403 is fixed to the base plate 101, and the other end of the sleeve 403 is fitted onto the other end of the anchor bolt 402. The sleeve uses the magnetic suction device 404 to attract and connect the anchor bolt 402. When the magnetic suction device 404 is energized, it is connected to the anchor bolt 402; when the power is off, it is disconnected from the anchor bolt 402.

[0133] There are two power failure sensors 107, which are used to send power on / off commands to the magnetic attraction device 404. One power failure sensor 107 is installed below the shock absorption device 106 and needs to be triggered by the shock absorption device 107; the other power failure sensor 107 is installed on the side guardrail 102 and needs to be triggered manually.

[0134] When the shock-absorbing device 106 extends or retracts to a certain extent, it triggers the power-off sensor 107 installed therein. The power-off sensor 107 issues a power-off command to cause the magnetic attraction device 404 to lose its magnetic force, thereby separating the anchor rod 402 from the sleeve 403.

[0135] After the anti-collision slide 103 is hit by a large collapsed rock, the inner side of the suspended basket device 1 separates from the rock mass; the rock mass exerts a normal force on the anti-collision slide 103; the normal force causes the suspended basket device 1 to rotate, thereby creating a gap between the suspended basket device 1 and the rock mass; the anti-collision slide 103 serves as a slide for the rock mass to slide down, falling through the gap; the personnel and equipment inside the suspended basket device 1 are prevented from being hit by the rock mass due to the rotation of the suspended basket device 1.

[0136] like Figure 6 The diagram shows the structure of the telescopic support sliding device 105, which includes a rubber tire 501, a wheel hub 502, a connecting shaft 503, a connecting rod 504, a hydraulic cylinder 509, a telescopic rod 505, a cylinder body 506, a bracket 507, and a manual hydraulic pump 508.

[0137] A rubber tire 501 is mounted on a wheel hub 502; a connecting shaft 503 passes through a hole in the middle of the wheel hub 502 to connect the two; the wheel hub 502 is connected to a connecting rod 504 via the connecting shaft 503; the connecting rod 504 is connected to the telescopic rod 505 of the hydraulic cylinder 509; the connecting rod 504 includes a U-shaped steel plate and a round steel bar, forming a pulley system with the connecting shaft 503; the cylinder body 506 of the hydraulic cylinder 509 is fixed to the base plate 101 via a bracket 507; the extension and retraction of the hydraulic cylinder 509 supports the suspended platform 1 against the rock wall; the hydraulic cylinder 509 is fixed to the upper surface of the base plate 101; a manual hydraulic pump 508 supplies oil to the hydraulic cylinder 509; the manual hydraulic pump 508 has a valve to adjust the return oil volume to prevent the return oil speed from being too fast.

[0138] like Figure 7 The diagram shows the planar layout of the shear anchor piles 305 on the ground. A total of four shear anchor piles 305 are required for the suspended platform. Two shear anchor piles 305 are located at each end of the suspended platform device 1. The two anchor piles closer to the free surface provide tension to the outside of the suspended platform device 1, and the two anchor piles farther from the free surface provide tension to the inside of the suspended platform device 1.

[0139] The design methods for the spacing and length of the shear anchor piles are described below:

[0140] The design of the spacing and length of the shear anchor piles requires calculations of rock mass overturning resistance and sliding resistance. The design is based on the critical state of the rock mass when it is about to overturn or slide, and the overturning resistance and sliding resistance must be met simultaneously.

[0141] The rock mass is about to collapse along the horizontal plane (m) where the bottom of the pile is located. A m B The entire rock mass tilts at the intersection line (O) with the rock wall; the bottom surface of the toppled rock mass is at the horizontal plane where the bottom of the pile is located (m). A mB ), that is, the straight line m in the front view. A m B The inner surface of the collapsed rock mass is the vertical plane where the pile is located (n0, n1, n2), which is the straight line n0, n1, n2 in the top view.

[0142] When the rock mass tilted, its bottom surface separated from the lower rock mass, i.e., along the straight line m in the front view. A m B When the rock mass tilts, its side separates from the rock mass away from the rock wall, that is, along the straight lines n0, n1, n2 in the top view;

[0143] The forces acting on the rock mass when it is about to topple include: the rock mass's own weight G, the horizontal tension F exerted by the cable tension on the toppleting rock mass, and the normal distributed force σ generated by the rock mass's own tensile properties on the vertical planes (n0, n1, n2). l The tensile properties of the rock mass itself in the horizontal plane (m) A m B The normal distributed force σ generated on ) m ;

[0144] When the rock mass slips, it slides outward along the horizontal plane where the bottom of the pile is located. The forces acting on the rock mass include the normal distributed force σ generated by the tensile properties of the rock mass itself on the vertical plane (n0, n1, n2). l Horizontal plane where the bottom of the pile is located (m) A m B The shear force τ m .

[0145] Therefore, the design method for the spacing and length of the shear anchor piles includes two cases: the top view of the rock wall shows an arc-shaped edge and a linear edge. The arc-shaped edge means that the rock mass on both sides of the shear anchor pile in the y-direction is in a free state and is not constrained by the external surrounding rock; the linear edge means that the shear anchor pile is constrained by the surrounding rock extending far to both sides in the y-direction (the unaffected area is defined as the far distance).

[0146] The rock mass collapse and failure process is divided into three stages: Stage I, Stage II, and Stage III;

[0147] Stage I is the initial development stage. In the anti-tipping calculation, at this stage, only the ground rock mass on the vertical plane (n0, n1, n2) first experiences tensile failure, while the horizontal plane (m) of the rock mass is ignored. A m B The normal distributed force σ generated on ) m In the anti-sliding calculation: the rock mass is subjected to a normal distributed force σ generated on the vertical plane (n0, n1, n2) due to its own tensile properties. l The shear force τ at the horizontal plane where the bottom of the pile is located m ;

[0148] Stage II is the intermediate toppling stage. In the toppling resistance calculation, at this time, the rock mass has already undergone tensile failure on the vertical planes (n0, n1, n2), and no longer generates a normal distributed force σ on the toppling rock mass. m Only on the horizontal plane of the rock mass (m) A m B A normal distributed force σ is generated on the surface. m In the anti-sliding calculation: the rock mass is only affected by the horizontal plane where the bottom end of the pile is located (m). A m B The shear force τ m ;

[0149] Stage III is the final toppling stage. In the toppling resistance calculation, at this time the rock mass is in both the vertical plane (n0, n1, n2) and the horizontal plane (m). A m B The values ​​above have all exceeded the tensile strength σ of the rock mass. l,max It undergoes tensile failure and no longer generates a normal distributed force σ on the toppled rock mass. l and σ m Only the weight of the rock mass is used to resist the toppling; in the anti-sliding calculation: since both the vertical and horizontal planes are cracked, it is no longer necessary to perform anti-sliding calculations;

[0150] The judgment criteria for rock mass toppling instability are based on the critical bending moment value of the rock mass at the edge curve O and the horizontal plane (m) at the bottom of the anchor pile. A m B The critical value of the sliding force;

[0151] The calculation methods for the critical bending moment and anti-slip force in the case of the arc-shaped edge are as follows:

[0152] S1: Calculation process for overturning resistance of two shear anchor piles A (taking two anchor piles near the free face as an example):

[0153] Normal force σ (vertical plane: σ) l Horizontal plane: σ m The bending moment M generated by the weight of the rock mass G on curve O σ and M G The sum must be greater than the bending moment M generated by the tension F. F :

[0154] M σ +M G >M F

[0155] S2: Calculation process for anti-slip of two shear anchor piles A (taking two anchor piles near the free face as an example):

[0156] The normal force σ distributed on the vertical plane (n0, n1, n2) due to the tensile properties of the rock mass itself l (Calculate the tension F) l,σ ) and the horizontal plane where the bottom of the pile is located (m A m B The shear stress τ m (shear force F) m,τ The sum of these forces is greater than the horizontal force F generated by the cable tension F:

[0157] F l,σ +F m,τ >2F

[0158] S3: The calculations in stage I must satisfy:

[0159]

[0160] in:

[0161]

[0162] σ0=(G+4F) / S m ;

[0163] S4: The calculation for stage II is as follows:

[0164]

[0165] S5: The calculation for stage III is as follows:

[0166]

[0167] In the formula, l is the pile length; m A Let n0 be the distance between pile A (closest to the free face) and the free face (curve O); n0 is the spacing between the two piles in the y direction; n1 and n2 are the distances between the two piles in the y direction and the free faces on both sides, respectively; S l = l(n0+n1+n2), where σ is the area of ​​the vertical plane (n0, n1, n2); l,max This represents the tensile strength of the rock mass; according to the theory of mechanics of materials, the triangular distributed force is converted into a concentrated force at 2 / 3 of the triangle, therefore... Before the rock mass cracks on the vertical plane (n0, n1, n2), the tensile strength of the rock mass is the maximum normal force (horizontal direction) provided by the toppled rock mass. The vertical distance between the converted concentrated force and curve O; is the horizontal distance between the center of gravity of the rock mass and curve O; 2F is the tension in the two cables; S m =m(n0+n1+n2) is the horizontal plane (m A m B The area of ​​) The maximum normal force (vertical direction) provided by the tensile strength of the rock mass on the horizontal plane for the toppling rock mass after the rock mass cracks on the vertical plane and before it cracks on the horizontal plane at the bottom; σ0 is the vertical distance between the converted concentrated force and curve O; σ0 is the normal force generated on the horizontal plane by the weight of the rock mass and the tension of the four cables. c is the friction angle of the rock mass; c is the cohesion of the rock mass.

[0168] Therefore, in the design process of the shear anchor pile spacing and pile length, parameter m A The selection of values ​​for l is considered to be in the safest state when it meets the calculation formula of stage I, and at the very least, it must meet the calculation formula of stage III; otherwise, the rock mass will experience toppling or sliding failure. Among them, the parameters n0, n1, and n2 are determined based on the conditions of the rock wall edge.

[0169] In the calculation of the two shear anchor piles B far from the free face, m can be added based on A. A Replace with m B That is enough (m) B (This refers to the distance between pile group B (far from the free face) and the free face (curve O); When the shear anchor pile A satisfies the condition, as long as m B ≥m A Shear anchor pile B will naturally meet the requirements.

[0170] The calculation methods for the critical bending moment and anti-slip force in the linear edge case are as follows:

[0171] When the rock mass edge is linear, the overturned rock mass does not overturn along the vertical plane as a whole, including the rock masses on both sides. Instead, the overturning only occurs within the rock mass affected by the shear anchor piles (excluding the rock mass outside the affected area). According to the elasticity mechanics, the influence range of the hole excavation is 3 to 5 times the hole diameter. For safety considerations, the influence range of the shear anchor piles on both sides is taken as 3n0.

[0172] S1: Calculation process for overturning resistance of two shear anchor piles A (taking two anchor piles near the free face as an example):

[0173] Normal force σ (vertical plane: σ) l Horizontal plane: σ m The bending moment M generated by the weight of the rock mass G on curve O σ and M G The sum must be greater than the bending moment M generated by the tension F. F :

[0174] M σ +M G >M F

[0175] S2: Calculation process for anti-slip of two shear anchor piles A (taking two anchor piles near the free face as an example):

[0176] The normal force σ distributed on the vertical plane (n0, n1, n2) due to the tensile properties of the rock mass itself l (Calculate the tension F) l,σ ) and the horizontal plane where the bottom of the pile is located (m A m B The shear stress τ m (Calculate the shear force F) m,τ The sum of these forces is greater than the horizontal force F generated by the cable tension F:

[0177] F l,σ +F m,τ >2F

[0178] From the shear anchor pile to the outside of the influence range, the normal force generated by the tensile properties of the rock mass gradually decreases to both sides, which can be simplified as a linear decrease;

[0179] S3: The calculation for stage I is as follows:

[0180]

[0181] in:

[0182]

[0183] σ0=(G+4F) / S m ;

[0184] S4: The calculation for stage II is as follows:

[0185]

[0186] S5: The calculation for stage III is as follows:

[0187]

[0188] In the formula, l is the pile length; m A Let n0 be the distance between pile A (closest to the free face) and the free face (curve O); n0 is the spacing between the two piles in the y direction; n1 and n2 are the distances between the two piles in the y direction and the free faces on both sides, respectively; S l,n0 =ln0 and 2·S l,3n0 =6·ln0, where 6 represents the area of ​​the middle region and the two side regions of the vertical plane, respectively; This is the normal force generated on the vertical plane over the area of ​​both sides. Since the loads on both sides are triangularly distributed in both the vertical and horizontal directions, it needs to be multiplied by 1 / 2 twice. The normal force (horizontal direction) generated by the area of ​​the middle region on the vertical plane; It is the sum of the normal forces on the vertical plane; σ l,max The tensile strength of the rock mass is given; according to the theory of mechanics of materials, the triangular distributed force is converted into a concentrated force at 2 / 3 of the triangle. The vertical distance between the converted concentrated force and curve O; 2F is the horizontal distance between the center of gravity and curve O; 2F is the tension in the two cables. The normal force generated on the bottom horizontal plane by the area of ​​both sides; The normal force (vertical direction) generated by the area of ​​the middle region on the bottom horizontal plane; σ0 is the sum of the normal forces on the horizontal plane; σ0 is the normal force generated on the horizontal plane by the weight of the rock mass and the tension of the four cables. c is the friction angle of the rock mass; c is the cohesion of the rock mass.

[0189] Therefore, in the design process of the shear anchor pile spacing and pile length, parameter m A The selection of values ​​for l is considered to be in the safest state when it meets the calculation formula of stage I, and at the very least, it must meet the calculation formula of stage III; otherwise, the rock mass will collapse and fail. Among them, the parameters n0, n1, and n2 are determined based on the conditions of the rock wall edge.

[0190] In the calculation of the two shear anchor piles B far from the free face, based on A, m A Replace with m B That is enough (m) B (This refers to the distance between pile group B (far from the free face) and the free face (curve O); When the shear anchor pile A satisfies the condition, as long as m B ≥m A Shear anchor pile B will naturally meet the requirements.

[0191] The design method for the spacing and length of the shear anchor piles is biased towards safety considerations. In actual design, it should be ensured that there is more than 3 times the safety redundancy in the first stage.

[0192] This embodiment also provides an installation method for a suspended platform used for anchoring unstable rock masses at steep cliffs, comprising the following steps:

[0193] (1) Based on the calculation method of shear anchor pile 305, design the spacing m, n and pile length l: drill a hole with a diameter of 250mm in the ground rock mass, insert a steel pipe with a diameter of 200mm, backfill with cement grout, and install cable 302 to bear shear force after the strength is sufficient; install guide pulley 304 on the ground and extend it to the free surface;

[0194] (2) The suspended platform device 1 is welded on site using I-beams, square tubes, and steel plates: First, the base plate 101 is welded, and a 10mm steel plate is laid on the frame; then the side guardrail 102 is welded, and a 3mm steel plate is closed at the position 1m below the side guardrail 102; then the shock-absorbing device 106 is installed on the side guardrail 102; then the anti-smashing slide 103 is welded, the lower part of the anti-smashing slide 103 is a 10mm thick steel plate, and the upper part is a 50mm diameter round tube laid at 300mm intervals, and the laying direction is downward along the slope; finally, the anti-smashing slide 103 is installed above the shock-absorbing device 106; during the welding process, the following installation holes are reserved: winch 3012, gearbox 204 of lifting work platform 2, telescopic support sliding device 105, and separable anchor support leg 104;

[0195] (3) The frame of the welding lifting platform 201 is made of I-beams welded longitudinally and transversely into a square steel frame, and an M100 T-nut 203 is fixed at each of the four corners.

[0196] (4) Install the lifting platform 2: Install the gearbox 204, motor 205, and T-screw 202 of the lifting platform 2 at the four corners of the base plate 101 of the suspended platform device 1. Align the T-screw 202 with the T-nut 203 on the lifting platform 201. Drive the T-screw 202 to rotate into the T-nut 203 through the motor 205 to complete the installation of the lifting platform 2.

[0197] (5) Install telescopic support sliding device 105: Install the hydraulic cylinders of the two telescopic support sliding devices 105 at the two ends of the base plate 101 of the suspended platform device 1, connect the rubber tire 501, wheel hub 502, connecting shaft 503, connecting rod 504 to the hydraulic cylinders, and fix the manual hydraulic pump 508 to the base plate 101 of the suspended platform device 1.

[0198] (6) Install the lifting cable system 3: Install the winch 301 of the lifting cable system 3 at the four corners of the base plate 301 of the suspended platform device 1, fix the positioning pulley 303 above the side guardrail 102, and lock the cable 301 on the winch 301 after it is wrapped around the positioning pulley 303 and wrapped around the shear anchor pile 305 once.

[0199] (7) Lifting basket device 1: Use a truck crane to lift the basket device 1 from the ground to the open surface. During this process, put the cable 302 into the groove of the guide pulley 304. After lifting to a certain height, operate the hydraulic cylinder of the telescopic support sliding device 105 so that the rubber tire 501 is supported on the rock wall and the basket device 1 can slide slowly down the rock wall.

[0200] (8) Adjust the horizontal state of the suspended platform device 1 by using the winch 301, and gradually loosen the cable of the truck crane so that the suspended platform device 1 can start to slide down to the designated working position by the winch 301 itself.

[0201] (9) Drill holes on the rock wall at a position higher than the bottom plate 101 of the suspended platform device 1, install anchor rods 402, and carry out grouting; install sleeves 403 on the side guardrail 102, and install magnetic suction devices 404 inside the sleeves 403 to attract anchor rods 402, so that the suspended platform device 1 becomes one with the rock mass, and prevents the suspended platform device 1 from shaking in the direction perpendicular to the rock wall during construction.

[0202] (10) The installation process of the basket-type sliding platform for anchoring dangerous rock masses at steep cliffs can be realized by following steps (1) to (9).

[0203] This invention provides a suspended platform and method for anchoring unstable rock masses on steep cliffs. The device features an anti-collision sliding track combined with detachable anchor legs, enabling timely separation of the suspended platform from the rock mass and effectively mitigating damage to the working platform in the event of rock mass collapse and instability. An internal lifting platform allows for flexible vertical movement within a small area, in addition to moving within the overall elevation range. Shear anchor piles provide the suspended platform with significant load-bearing capacity. This device can be applied to construction operations on steep cliffs with high free-face areas.

[0204] The above description represents the preferred embodiments of the present invention. It should be noted that those skilled in the art can make various improvements and modifications without departing from the principles of the present invention, and these improvements and modifications should also be considered within the scope of protection of the present invention.

Claims

1. A suspended platform for anchoring unstable rock masses at steep cliffs, characterized in that, include: Suspended platform device, lifting work platform, lifting cable system; The suspended platform device includes a base plate, side railings, anti-smashing slide rails, telescopic support sliding device, detachable anchor legs, shock absorption device, and power failure sensor. Side railings are welded to the sides of the base plate. The anti-smashing slide rails connect four side railings. The shock absorption device is installed between the anti-smashing slide rails and the side railings to reduce the impact force of the anti-smashing slide rails on the side railings. The anti-smashing slide rails are top plate structures that connect the inner and outer sides of the side railings. The outer side of the top plate structure is inclined upward at 45°. The telescopic support sliding device includes a rubber tire and a telescopic mechanism connected to the rubber tire. The telescopic mechanism is fixedly connected to the suspended basket device. The telescopic mechanism is used to adjust the length according to the concave and convex shape of the rock wall during the up and down movement of the suspended basket device, so that the rubber tire is supported on the rock wall and the suspended basket device moves smoothly. The detachable anchor support leg includes an anchor rod fixed to the rock wall, a sleeve fixed to the base plate, and a magnetic suction device installed inside the sleeve. The outer end of the anchor rod is inserted into the sleeve and contacts the magnetic suction device. The power failure sensor is used to send a power on / off command to the magnetic suction device to connect or separate the magnetic suction device from the anchor rod. When the anti-collision slide is hit by a collapsing rock, it triggers a power-off sensor to issue a power-off command, causing the magnetic attraction device to separate from the anchor rod, and then causing the inner side of the suspended basket device to separate from the rock mass; the normal force generated by the rock on the anti-collision slide causes the suspended basket device to rotate, thereby creating a gap between the suspended basket device and the rock mass, and the anti-collision slide serves as a slide for the rock to slide down and fall through the gap between the suspended basket device and the rock mass; The lifting platform is installed on the suspended basket device, and the suspended basket device serves as the base of the lifting platform. The lifting platform includes a lifting platform and a lifting device that drives the lifting platform to move up and down. The lifting cable system includes a winch, a cable, and shear anchors. The shear anchors are fixed to the ground, and the upper end of the cable passes around the shear anchors and is locked to them with a locking buckle. The lower end of the cable is connected to the winch inside the suspended platform. The lifting and lowering of the suspended platform is achieved by the winch winding and unwinding the cable.

2. The suspended platform for anchoring dangerous rock masses at steep cliffs according to claim 1, characterized in that: The base plate is a square frame welded longitudinally and transversely from I-beams, and a steel plate is laid on top of the base plate; The side railing is a mesh structure welded from square tubes, and the bottom part is enclosed by iron plates. The lower part of the top plate structure is a steel plate, and the upper part is a series of intermittently laid circular pipes, laid in a downward direction along the slope. The anti-smashing track is connected to the inner and outer sides of the side guardrail by a shock-absorbing device, which includes an inner cylinder and an outer thick spring.

3. A suspended platform for anchoring unstable rock masses at steep cliffs, as described in claim 1, is characterized in that: The telescopic mechanism includes a wheel hub, a connecting shaft, a connecting rod, a hydraulic cylinder, and a manual hydraulic pump. The rubber tire is mounted on the wheel hub. The connecting shaft passes through a hole in the middle of the wheel hub to connect the rubber tire to the wheel hub. The connecting rod includes a U-shaped steel plate and a round steel bar, forming a pulley system with the connecting shaft. The connecting rod is connected to the telescopic rod of the hydraulic cylinder. The hydraulic cylinder is fixed to the upper surface of the base plate. The manual hydraulic pump supplies oil to the hydraulic cylinder. The manual hydraulic pump has a valve to adjust the return oil volume.

4. A suspended platform for anchoring unstable rock masses at steep cliffs, as described in claim 1, characterized in that: One end of the anchor rod is horizontally fixed inside the rock mass, and the other end extends to the side guardrail. When installing the anchor rod, a drilling machine is used to drill a hole in the rock wall, and after it is inserted, grouting is performed to anchor it. One end of the sleeve is fixed to the base plate, and the other end is fitted onto the other end of the anchor rod. The magnetic attraction device is placed inside the sleeve, and when energized, it generates magnetic force and attracts the end of the anchor rod together. There are two power failure sensors. One power failure sensor is installed below the shock absorption device and is triggered by the shock absorption device; the other power failure sensor is installed on the side guardrail and is triggered manually.

5. A suspended platform for anchoring unstable rock masses at steep cliffs, as described in claim 1, characterized in that: The lifting device includes a T-screw, a T-nut, a reduction gearbox, a motor, and a control handle; The lifting platform is a square steel frame welded longitudinally and transversely from I-beams; A T-nut is fixed at each of the four corners of the lifting platform; A reduction gearbox is fixed at each of the four corners of the base plate; the reduction gearbox is used to reduce the rotational speed of the T-screw. The lower end of the gearbox is connected to the motor; the upper output shaft of the gearbox is fixedly connected to the T-screw via a connector; the T-screw is screwed into the T-nut; The motor can rotate in both forward and reverse directions; the motor drives the T-shaped screw to rotate, thereby realizing the up and down movement of the lifting platform; The control handle is used to start and stop the motor, as well as to adjust the motor's forward and reverse rotation.

6. A suspended platform for anchoring unstable rock masses at steep cliffs, as described in claim 1, characterized in that: The lifting cable system also includes guide pulleys and positioning pulleys; One winch is installed at each of the four corners of the base plate; A positioning pulley is installed at each of the four corners of the side guardrail to support the cable and prevent friction against the suspended basket device; The guide pulley is fixed to an I-beam; the I-beam is bolted to the ground, so that the guide pulley extends out of the ground to the free surface, which is used to change the direction of the cable from nearly horizontal to nearly vertical; The cable is connected to the winch at its lower end via the guide pulley and the positioning pulley, and its upper end is locked by the latch after passing around the shear anchor pile, thereby realizing the connection between the cable and the shear anchor pile; The winch enables the overall vertical movement of the suspended platform by winding and unwinding the cable. The shear anchor pile uses its own shear resistance to provide tension for the cable; the shear anchor pile is drilled in the ground rock mass, then a steel pipe is inserted, and finally backfilled with cement grout.

7. A suspended platform for anchoring unstable rock masses at steep cliffs, as described in claim 1, characterized in that: The design methods for the spacing and length of the shear anchor piles include two cases: the top view of the rock wall shows an arc-shaped edge and a linear edge; the arc-shaped edge refers to the shear anchor piles in... The rock masses on both sides of the direction are in a free state and are not constrained by the external surrounding rock; the linear edge is where the shear anchor pile is located. The direction is constrained by the surrounding rock extending far to both sides; The design of the spacing and length of the shear anchor piles requires calculations of rock mass overturning resistance and sliding resistance. The design should be based on the critical state of the rock mass when it is about to overturn or slide, and the overturning resistance and sliding resistance should be satisfied simultaneously. The rock mass collapse and failure process is divided into three stages: Stage I, Stage II, and Stage III; Stage I is the initial development stage, and in the anti-tipping calculation: at this time, the rock mass is only in the vertical plane ( , , The ground rock mass on the surface first undergoes tensile failure, ignoring the horizontal plane of the rock mass ( , Normal distributed force generated on ) In anti-sliding calculations: the rock mass is subjected to its own tensile properties in the vertical plane ( , , Normal distributed force generated on ) Shear force on the horizontal plane where the bottom of the pile is located ; Stage II is the intermediate toppling stage. In the toppling resistance calculation: at this time, the rock mass is in the vertical plane ( , , The rock mass has already undergone tensile failure and no longer exerts normal distributed forces on the toppled rock mass. Only on the horizontal plane of the rock mass ( , Normal distributed force is generated on ) In the anti-sliding calculation: the rock mass is only affected by the horizontal plane where the bottom end of the pile is located ( , shear force ; Stage III is the final toppling stage. In the toppling resistance calculation: at this time, the rock mass is in the vertical plane ( , , ) and horizontal plane ( , The above values ​​have all exceeded the tensile strength of the rock mass. It undergoes tensile failure and no longer generates normal distributed forces on the toppled rock mass. and Only the weight of the rock mass is used to resist the toppling; in the anti-sliding calculation: since both the vertical and horizontal planes are cracked, it is no longer necessary to perform anti-sliding calculations; The toppling instability of the rock mass depends on the bending moment at the free surface of the rock mass and the horizontal plane at the bottom of the shear anchor pile. , The relationship between the sliding force and the instability critical value.

8. A suspended platform for anchoring unstable rock masses at steep cliffs, as described in claim 7, characterized in that: In the case of the arc-shaped edge, the spacing and length of the shear anchor piles are determined by the bending moment of the rock mass at the free face of the edge and the sliding force and instability critical value of the bottom horizontal plane of the shear anchor piles. S1: Two shear anchor piles Anti-tipping calculation process: Normal force and rock gravity Bending moment generated on the free surface and The sum must be greater than the tension. The resulting bending moment : ； S2: Two shear anchor piles Anti-slip calculation process: Due to the tensile properties of the rock mass itself in the vertical plane ( , , Normal distributed force on ) Calculated tension and the horizontal plane where the bottom of the pile is located shear stress Shear force The sum of these forces is greater than the horizontal force generated by the cable tension. : ； S3: The calculations in stage I must satisfy: ； in: ， ； S4: The calculation for stage II is as follows: ； S5: The calculation for stage III is as follows: ； In the formula, The length of the pile; for The distance between the pile foundation and the free face; for The distance between two stakes in the direction; and They are respectively The distance between the two piles and the open surfaces on both sides; For vertical plane ( , , The area of ​​) The tensile strength of the rock mass; based on the theory of mechanics of materials, the triangular distributed force is converted into a triangular... Concentration at that point, therefore For vertical plane ( , , Before the rock mass cracks, the tensile strength of the rock mass is the maximum normal force provided by the toppled rock mass; This represents the calculated concentrated force and vertical distance from the free surface. This is the horizontal distance between the center of gravity of the rock mass and the free surface. The tension in the two cables; The horizontal plane where the bottom end of the pile is located The area; The maximum normal force provided by the tensile properties of the rock mass on the horizontal plane for the toppling rock mass after the rock mass cracks on the vertical plane and before it cracks on the horizontal plane at the bottom; This represents the vertical distance between the converted concentrated force and the free surface. The normal force generated on the horizontal plane by the weight of the rock and the tension of the four cables; The friction angle of the rock mass; The cohesion of the rock mass; In the design process of the shear anchor pile spacing and pile length, the parameters , The selected value represents the safest state when it meets the calculation formula of Stage I, and at the very least, it must meet the calculation formula of Stage III; otherwise, the rock mass will experience toppling or sliding failure. Among these, the parameter... , , It is determined based on the conditions at the edge of the rock face; Two shear anchor piles far from the free face In the calculation process Based on Replace with That's all. for The distance between the pile bank and the free face; when shear anchor piles Under the condition that it is satisfied, as long as Shear anchor piles They will naturally be satisfied.

9. A suspended platform for anchoring unstable rock masses at steep cliffs, as described in claim 7, characterized in that: In the linear edge case, the spacing and length of the shear anchor piles are determined by the bending moment of the rock mass at the edge free face and the sliding force and instability critical value of the bottom horizontal plane of the shear anchor piles. When the rock mass edge is linear, the toppling rock mass does not tilt along the vertical plane as a whole, including the rock masses on both sides. Instead, it only tilts within the rock mass affected by the shear anchor piles. Based on the principle of elasticity, the influence range of hole excavation is 3 to 5 times the hole diameter. For safety reasons, the influence range of the shear anchor piles on both sides is taken as... ; S1: Two shear anchor piles Anti-tipping calculation process: Normal force and rock gravity Bending moment generated on the free surface and The sum must be greater than the cable tension. The resulting bending moment : ； S2: Two shear anchor piles Anti-slip calculation process: The tensile properties of the rock mass itself in the vertical plane ( , , Normal distributed force on ) Calculated tension and the horizontal plane where the bottom of the pile is located shear stress Calculated shear force The sum of these forces is greater than the horizontal force generated by the cable tension. ； From the shear anchor pile to the outside of the influence range, the normal force generated by the tensile properties of the rock mass gradually decreases to both sides, which can be simplified as a linear decrease; S3: The calculation for stage I is as follows: ； in: ， ； S4: The calculation for stage II is as follows: ； S5: The calculation for stage III is as follows: ； In the formula, The length of the pile; for The distance between the pile foundation and the free face; for The distance between two stakes in the direction; and They are respectively The distance between the two piles and the open surfaces on both sides; and , respectively, are the areas of the middle region and the two side regions of the vertical plane; This represents the normal force generated on the vertical plane across the area of ​​both sides. Since the loads on both sides are triangularly distributed in both the vertical and horizontal directions, it needs to be multiplied twice. ; The normal force generated on the vertical plane by the area of ​​the intermediate region; It is the sum of the normal forces on the vertical plane; The tensile strength of the rock mass; based on the theory of mechanics of materials, the triangular distributed force is converted into a triangular... Concentration at that point This represents the vertical distance between the converted concentrated force and the free surface. The horizontal distance between the center of gravity and the free surface; The tension in the two cables; The normal force generated on the bottom horizontal plane by the area of ​​both sides; The normal force generated by the area of ​​the middle region on the bottom horizontal plane; It is the sum of the normal forces on the horizontal plane; The normal force generated on the horizontal plane by the weight of the rock and the tension of the four cables; The friction angle of the rock mass; The cohesion of the rock mass; In the design process of the shear anchor pile spacing and pile length, the parameters , The selected value represents the safest state when it meets the calculation formula of Stage I, and at the very least, it must meet the calculation formula of Stage III; otherwise, the rock mass will collapse and fail. Among these, the parameter... , , It is determined based on the conditions at the edge of the rock face; Two shear anchor piles far from the free face In the calculation process Based on Replace with That's all. for The distance between the pile bank and the free face; when shear anchor piles Under the condition that it is satisfied, as long as Shear anchor piles They will naturally be satisfied.

10. The installation method of the suspended platform for anchoring dangerous rock masses at steep cliffs according to any one of claims 1-9, characterized in that, Includes the following steps: (1) Design the spacing and length of the shear anchor piles according to the calculation method: Drill holes in the ground rock mass, insert steel pipe piles, backfill with cement grout, and install cables to withstand shear force after the strength is sufficient; install guide pulleys on the ground and extend them to the free face; (2) The suspended platform device is welded on site using I-beams, square tubes, and steel plates: First, the base plate is welded, and steel plates are laid on the frame; then the side railings are welded, and steel plates are closed at the bottom of the side railings; then the shock-absorbing device is installed on the side railings; then the anti-smashing slide is welded, with steel plates at the bottom and round pipes laid at intervals on the top, and the laying direction is downward along the slope; finally, the anti-smashing slide is installed above the shock-absorbing device; during the welding process, the following installation holes are reserved: winch, lifting worktable gearbox, telescopic support sliding device, and separable anchor legs; (3) The frame of the welding lifting platform: I-beams are welded longitudinally and transversely to form a square steel frame, and a T-nut is fixed at each of the four corners; (4) Install the lifting platform: Install the gearbox, motor and T-bolt of the lifting platform at the four corners of the bottom plate of the suspended platform. Align the T-bolt with the T-nut of the lifting platform. Drive the T-bolt to rotate into the T-nut by the motor to complete the installation of the lifting platform. (5) Install telescopic support sliding device: Install the hydraulic cylinders of the two telescopic support sliding devices at the two ends of the bottom plate of the suspended platform device, connect the rubber tires, wheel hubs, connecting shafts, connecting rods to the hydraulic cylinders, and fix the manual hydraulic pump to the bottom plate of the suspended platform device; (6) Install the lifting cable system: Install the winch of the lifting cable system at the four corners of the bottom plate of the suspended platform, fix the positioning pulley above the side guardrail, and lock the cable on the winch around the positioning pulley and wrap it around the shear anchor pile once. (7) Lifting the overall suspended platform: Use a truck crane to lift the overall suspended platform from the ground to the open surface. During this process, put the cable into the guide pulley groove. After lifting to a certain height, operate the hydraulic cylinder of the telescopic support sliding device so that the rubber tires are supported on the rock wall and the suspended platform can slide slowly down the rock wall. (8) Adjust the horizontal state of the suspended platform by the winch, and gradually loosen the cable of the truck crane so that the suspended platform can start to slide down to the designated working position by the winch itself. (9) Drill holes on the rock wall at a position higher than the bottom plate of the suspended platform, install anchor rods, and carry out grouting; install sleeves on the side guardrails and install magnetic suction devices inside the sleeves to attract the anchor rods, so that the suspended platform and the rock mass become one, and prevent the suspended platform from shaking in the direction perpendicular to the rock wall during construction. (10) The installation process of the suspended basket sliding platform for anchoring dangerous rock masses at steep cliffs can be realized by following steps (1) to (9).

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