Method for excavating adjacent existing railway lines using a wall-type excavation method based on UAV mapping

Abstract

This invention belongs to the technical field of UAV surveying in railway engineering, specifically relating to a method for excavating a retaining wall in a cutting adjacent to an existing railway line based on UAV surveying. The method includes the following steps: 1. **Flight Route Planning:** Developing a flight path based on the slope of the cutting to be excavated; 2. **UAV Surveying:** Conducting surveys along the planned flight path; 3. **3D Topographic Map Creation:** Generating a 3D topographic map of the cutting slope based on aerial images and POS data; 4. **Excavation Plan:** Developing an excavation plan based on the 3D topographic map; 5. **Construction Preparation:** Reinforcing the top of the cutting slope to be excavated; 6. **Protective Frame Construction:** Erecting a mobile protective frame; 7. **Earthwork Excavation:** Excavating from the side of the new railway line towards the side of the existing railway line to form an excavation trench, reserving a retaining wall near the existing railway line during excavation; 8. Moving the mobile protective frame down the slope along the side of the existing railway line, excavating the earthwork for the retaining wall portion, and gradually moving the inner wall of the retaining wall outwards; repeating this process. This solution addresses the high safety risks associated with earthwork excavation in cuttings adjacent to existing railway lines.

Description

Technical Field

[0001] This invention belongs to the field of UAV surveying technology, specifically relating to a method for excavating a trench wall near an existing railway line based on UAV surveying. Background Technology

[0002] In railway engineering construction, excavation of earth and rock in road cuts adjacent to existing structures is very common. For example, when constructing auxiliary lines, designing lines close to existing lines, or rerouting parts of a railway, the new lines are usually adjacent to existing lines, necessitating road cut excavation without affecting the operation of the existing lines. Common methods for excavating near existing lines often involve horizontal or vertical stepped excavation, excavating layer by layer from top to bottom or from outside to inside. However, this method is a conventional "open-air" construction with high safety risks. Personnel, equipment, and materials are prone to falling into the existing lines. Not only is the construction risk high, but each layer requires measurement to control the excavation volume, resulting in slow progress and significant challenges in on-site management. Summary of the Invention

[0003] The present invention aims to provide a method for excavating a wall-type trench near an existing railway line based on UAV mapping, in order to solve the problem of high safety risks in earthwork excavation in trenches near existing railway lines.

[0004] To achieve the above objectives, the present invention provides a method for excavating a retaining wall-type trench near an existing railway line based on UAV mapping, comprising the following steps:

[0005] Plan the flight route: Plan the flight route based on the road cut slope to be excavated;

[0006] Drone survey: Control the drone to survey the road cut slope to be excavated along the designated flight path;

[0007] 3D topographic map creation: Extract aerial images captured by the five-lens tilt camera on the UAV, as well as the UAV's POS data; generate a 3D topographic map of the cut slope based on the aerial images and POS data.

[0008] Planning: Develop an excavation plan based on the 3D topographic map of the road cut slope;

[0009] Construction preparation: Reinforce the top of the cut slope to be excavated, and construct surface drainage ditches along the outer side of the new road slope.

[0010] Erect protective scaffolding: Erect mobile protective scaffolding on the outer side of the slope crest and fixed protective scaffolding on the slope foot;

[0011] Earthwork excavation in the road cut: Excavate from the side of the new line towards the side of the existing line to form an excavation trench. During excavation, a partition wall is reserved near the side of the existing line, with a top width of 1.8m to 2.2m and a trench depth of 3m to 5m. Move the movable protective frame down the side slope of the existing line and excavate the earthwork of the partition wall section, maintaining a top width of 1.8m to 2.2m. The distance between the top of the partition wall and the bottom of the excavation trench is not less than 2m. Expand the trench depth to 3m to 5m and gradually move the inner sidewall of the partition wall outward until the top width reaches 1.8m to 2.2m. Repeat this process of moving the movable protective frame down, excavating the partition wall earthwork, and expanding the trench until the trench reaches the design elevation. Then, remove the partition wall.

[0012] Slope protection: Reinforce and protect the slopes of the newly constructed line.

[0013] The working principle and beneficial effects of this scheme are as follows: Before excavating the cutting slope, a three-dimensional topographic map of the site is established using drones, providing data support for the formulation of the excavation plan. This scheme adopts the longitudinal trenching method with reserved partition walls, following the principle of "from top to bottom, from left to right, graded excavation, and graded protection." A longitudinal partition wall is reserved on the cutting slope near the existing line. The inner slope of the partition wall is constructed using a step-by-step excavation method with transverse layering and longitudinal segmentation. The partition wall is mechanically demolished during a concentrated large-scale maintenance window, which can effectively improve the construction progress, reduce the difficulty of construction organization, and ensure the safety of railway operation.

[0014] The reserved partition wall forms a natural barrier between the existing line and the road cutting trench, avoiding interference between the road cutting excavation, earthwork, transportation, drainage and other processes and the operation of the existing line, preventing the rolling of broken stones and ensuring the safety of the existing line operation.

[0015] Optionally, during the earthwork excavation of the road cut, the excavation surface of the newly constructed road slope shall maintain a longitudinal drainage slope of not less than 4%, a longitudinal drainage ditch shall be provided in the middle of the newly constructed road slope, and temporary drainage ditches shall be set on both sides of the transverse side of the excavation trench. This combination of longitudinal and transverse drainage methods ensures that there is no water accumulation on the construction site.

[0016] Optionally, the excavation slope ratio on the inner side of the partition wall should be no less than 1:0.2 to ensure the stability of the partition wall.

[0017] Optionally, the system includes a linear guide rail with a sliding block slidably connected to it. A section of the arm, 1.8m to 2.2m in length, is hinged to the sliding block. A second section of the arm, at least 3m in length, is hinged to the free end of the first section. The guide rail is horizontally installed on the side of the mobile protective frame facing the newly constructed slope. The first and second sections of the arm automatically fall onto the roadbed under gravity. The length of the first section is the top width of the reserved partition wall, and the length of the second section is the depth of the sidewall of the excavation trench. The first and second sections can slide longitudinally to measure the partition wall and the excavation trench. Measurement can be performed simultaneously with excavation, eliminating the need for surveyors to measure during excavation, significantly reducing workload, improving construction efficiency, greatly reducing on-site management difficulty, and ensuring the safety of construction personnel.

[0018] Optionally, an angle iron is installed on the lower side of the free end of the first boom section, with the side of the angle iron facing the second boom section being inclined. When the second boom section rests against the inclined surface of the angle iron, the tilt angle of the second boom section can be limited, making the excavation slope of the second boom section the same as that of the inner side of the partition wall, thereby achieving control over the slope of the side of the excavation trench.

[0019] Optionally, a rack is installed on the guide rail, parallel to the guide rail, and a motor is installed on the slide. A gear is connected to the output end of the motor, and the gear meshes with the rack. The motor drives the slide to move the first and second arm sections, thereby moving longitudinally with the excavation progress as the partition wall and trench are excavated, further improving excavation efficiency.

[0020] Optionally, it also includes a secondary rail, on which a secondary slide block is slidably connected. A section of rod is hinged to the secondary slide block, and a second section of rod is hinged to the free end of the first section of rod. The end of the second section of rod away from the first section of rod is hinged to a section of arm. The secondary rail is installed parallel to the guide rail on the movable protective frame. The distance between the secondary rail and the guide rail is equal to the distance between the hinge point of the second section of rod and the first section of arm and the slide block. In this way, when the first and second sections of rod are taut, the first section of arm can be in a horizontal state, which facilitates the horizontal measurement of the top width of the partition wall.

[0021] Optionally, during the flight route planning process, several control points are set up on the road cut slope, and the coordinates of the control points are determined.

[0022] In the process of creating a 3D topographic map, the coordinates of the 3D topographic map are also calibrated based on the image control points.

[0023] Optionally, the following steps are also included:

[0024] Set up a take-off and landing platform: Set up a take-off and landing platform on a flat area near the road cut slope, place the drone on the take-off and landing platform, and set up a control terminal outside the take-off and landing platform;

[0025] Excavation inspection: A data acquisition module is installed on the slide block. The data acquisition module includes a communication unit, a microprocessor unit, and a Hall sensor that are electrically connected. The Hall sensor counts the number of rotations of the gear. The microprocessor unit calculates the moving distance of the first and second arm sections based on the number of rotations of the gear. The communication unit sends the calculated moving distance to the control terminal.

[0026] The control terminal receives and records the movement distance of the first and second boom sections. When the movement distance reaches a preset value, an inspection route is created and sent to the drone. The drone inspects the excavation work according to the inspection route. During the inspection, the drone takes off from the landing platform, flies to the front of the road cut slope, performs visual recognition based on the collected images, identifies the mobile protective frame, flies to the top of the mobile protective frame, controls the drone's gimbal to point the camera on the gimbal towards the excavation trench or excavation partition wall, and flies from one end to the other along the length of the mobile protective frame to collect images of the excavation trench or excavation partition wall. Finally, it returns and lands on the landing platform.

[0027] Optionally, during the setup of the take-off and landing platform, the five-lens tilt camera on the drone can be replaced with a monocular camera. Attached Figure Description

[0028] Figure 1 This is a diagram illustrating the excavation sequence of the method for excavating adjacent existing railway trenches using UAV mapping in Embodiment 1 of the present invention.

[0029] Figure 2 This is a schematic diagram of the movable protective frame and its auxiliary structures in the method for excavating adjacent existing railway trenches based on UAV mapping in Embodiment 1 of the present invention.

[0030] Figure 3 This is an enlarged schematic diagram of point A in Embodiment 1 of the present invention. Detailed Implementation

[0031] The following detailed description illustrates the specific implementation method:

[0032] The markings in the attached drawings of the instruction manual include: 1. Existing line slope, 2. New line slope, 3. Cut, 4. Mobile protective frame, 5. Fixed protective frame, 6. Surface drainage ditch, 7. Slope toe drainage ditch, 8. Guide rail, 9. Subrail, 10. Slide, 11. Sub-slide, 12. Motor, 13. First section boom, 14. Second section boom, 15. First section pole, 16. Second section pole, 17. Angle iron, 18. Partition wall, 19. Excavation trench.

[0033] Example 1

[0034] This embodiment is basically as follows: Figure 1 , Figure 2 , Figure 3 The method for excavating a retaining wall in a trench adjacent to an existing power line based on UAV mapping includes the following steps:

[0035] Flight route planning: A flight path will be planned based on the road cut slope to be excavated; several control points will be set up on the road cut slope, and their coordinates will be determined. Specifically, the flight area, flight altitude, and number of flights will be determined based on the road cut slope to be excavated. Three control points will be set up at both ends and the top of the road cut slope.

[0036] Drone survey: Control the drone to survey the road cut slope to be excavated along the designated flight path; in this embodiment, a drone equipped with a five-lens tilt camera is used to take aerial photos along the flight path.

[0037] 3D Topographic Map Creation: Extract aerial images captured by the five-lens tilt camera mounted on the UAV, as well as the UAV's POS data; generate a 3D topographic map of the cut slope based on the aerial images and POS data; calibrate the coordinates of the 3D topographic map based on the ground control points.

[0038] Planning: Based on the three-dimensional topographic map of the road cut slope, an excavation plan is formulated, which includes determining the construction locations of the fixed protective frame 5 and the mobile protective frame 4, as well as the excavation location of the earth and rock in the road cut 3.

[0039] Construction Preparation: Inspect the top and surface of the existing slope 1, and remove loose rocks and soil that threaten construction safety within the construction area. Investigate the natural drainage conditions of slopes and ditches within the construction site area, and construct temporary drainage facilities around the construction site. Reinforce the top of the cut slope to be excavated using frame beams, and construct surface intercepting drainage ditch 6 along the outer side of the new slope 2, as shown in the attached diagram. Figure 1 ① in the middle.

[0040] Erecting Protective Frames: A mobile protective frame 4 is erected on the outer side of the slope crest, and a fixed protective frame 5 is erected at the slope foot. The mobile protective frame 4 also includes auxiliary structures: A straight guide rail 8 and a secondary rail 9 are horizontally installed on the side of the mobile protective frame 4 facing the construction slope. Both the guide rail 8 and the secondary rail 9 have an I-shaped cross-section, forming upward and downward slots. A slide block 10 is slidably connected to the guide rail 8. The slide block 10 has a C-shaped cross-section, with its upper end engaging in the upward slot of the guide rail 8. A rack is laid along the length of the guide rail 8 in the downward slot. A motor 12 is installed on the slide block 10, and a gear is connected to the output end of the motor 12, meshing with the rack. A section arm 13 is hinged to the slide block 10, with a length of 2m. A second section arm 14, with a length of at least 4.5m, is hinged to the free end of the first section arm 13. An angle iron 17 is installed on the lower side of the free end of the first arm 13. The side of the angle iron 17 facing the second arm 14 is inclined, with a slope of 1:0.2. The secondary rail 9 is located above the guide rail 8, and the distance between the secondary rail 9 and the guide rail 8 is 1.5m. A slide block 10 and a secondary slide block 11 are slidably connected to the secondary rail 9. The cross-section of the slide block 10 and the secondary slide block 11 is C-shaped, and the upper end of the slide block 10 and the secondary slide block 11 is engaged in the upward slot of the guide rail 8. A rod 15 is hinged to the slide block 10 and the secondary slide block 11. A second rod 16 is hinged to the free end of the first rod 15. The end of the second rod 16 away from the first rod 15 is hinged to the first arm 13. The distance from the hinge point of the second rod 16 and the first arm 13 to the slide block 10 is 1.5m. The movable protective frame 4 and its attached structures are shown in the attached figure. Figure 3 As shown.

[0041] Road cut earthwork excavation: Excavation sequence as attached Figure 1 As shown. Excavation begins from the side of the new line towards the side of the existing line, forming excavation trench 19②. The excavation surface of the new line slope 2 maintains a longitudinal drainage slope of not less than 4%. A longitudinal drainage ditch is provided in the middle of the new line slope 2, and temporary drainage ditches are set on both sides of the excavation trench 19 laterally. During excavation, a partition wall 18③ is reserved near the side of the existing line. The top width of the partition wall 18 is 2m, and the depth of the excavation trench 19 is 5m. The movable protective frame 4 is moved down along the side slope of the existing line, and the earth and rock of the partition wall 18③ are excavated, maintaining a top width of 2m. The distance between the top of the partition wall 18 and the bottom of the excavation trench 19 is not less than 2m. The depth of the excavation trench 19 is expanded to 5m, and the inner sidewall of the partition wall 18 is gradually moved outward, thus completing the excavation. Figure 1 Excavation of section ④ continues until the top width reaches 2m; this process is repeated, moving the protective frame 4 downwards, excavating the earthwork of partition wall 18, and widening the excavation trench 19, in sequence completing sections ⑤, ⑥, ⑦, ⑧, ⑨, and ⑩. , , , , , Until trench 19 was excavated After reaching the design elevation, remove 18 sections of the partition wall. .

[0042] Slope protection: The newly built slope 2 is reinforced and protected, and a drainage ditch 7 is constructed at the toe of the slope.

[0043] In this embodiment, the longitudinal trenching method of the pre-reserved partition wall 18 is adopted, following the principle of "from top to bottom, from left to right, graded excavation, and graded protection." This forms a natural barrier between the existing line and the excavation trench 19 of the cutting 3, preventing the excavation, transportation, and drainage of earth and rock from the cutting 3 from interfering with the operation of the existing line, preventing the rolling of loose stones, and ensuring the safety of the existing line operation. The inner slope of the partition wall 18 is constructed using a horizontal layering and longitudinal segmentation method with stepped excavation. The partition wall 18 is mechanically demolished during a concentrated large-scale construction window, which can effectively improve the construction progress, reduce the difficulty of construction organization, and ensure the safety of railway operation.

[0044] During the excavation of the road cut 3, the first arm 13 and the second arm 14 automatically fall down under gravity. Then, under the action of the first rod 15, the second rod 16, and the angle iron 17, the first arm 13 is horizontally suspended on the road cut 3. The length of the first arm 13 is the top width of the reserved partition wall 18. The second arm 14 is tilted downward at a fixed angle to the first arm 13. The length of the second arm 14 is the depth of the side wall of the excavation trench 19, and the tilt angle is the slope of the side wall of the excavation trench 19. Moreover, driven by the motor 12, the first arm 13 and the second arm 14 can also move horizontally (i.e., in the longitudinal direction) with the progress of excavation. This allows for simultaneous excavation and measurement, eliminating the need for surveyors to measure during excavation, significantly reducing workload, improving construction efficiency, greatly reducing on-site management difficulty, and ensuring the safety of construction personnel.

[0045] Example 2

[0046] The difference between this embodiment and Embodiment 1 is that the method for excavating adjacent existing power line trenches using UAV mapping in this embodiment further includes the following steps:

[0047] Set up a take-off and landing platform: Set up a square take-off and landing platform on a flat area near the road cut slope, and lay metal plates on it. Set up guardrails around the perimeter of the take-off and landing platform, replace the five-lens tilt camera with a single-lens camera, and then place the UAV on the take-off and landing platform. Set up a control terminal outside the take-off and landing platform; in this embodiment, the control terminal is a mobile workstation.

[0048] Excavation inspection: Install a data acquisition module on the slide block 10. The data acquisition module includes a communication unit, a microprocessor unit, and a Hall sensor that are electrically connected. The Hall sensor counts the number of rotations of the gear. The microprocessor unit calculates the moving distance of the first arm 13 and the second arm 14 based on the number of rotations of the gear. The communication unit sends the calculated moving distance to the control terminal.

[0049] The control terminal receives and records the movement distance of the first arm 13 and the second arm 14. When the movement distance reaches the preset value, an inspection route is created and sent to the drone. The drone inspects the excavation construction according to the inspection route. During the inspection, the drone takes off from the take-off and landing platform, flies to the front of the road cut slope, performs visual recognition based on the collected images, identifies the mobile protective frame 4, and then flies to the top of the mobile protective frame 4. The drone's gimbal is controlled so that the camera mounted on the gimbal faces the excavation trench 19 or the excavation partition wall 18. The drone flies from one end to the other along the length of the mobile protective frame 4 to collect images of the excavation trench 19 or the excavation partition wall 18. Finally, the drone returns to the take-off and landing platform and sends the collected images to the control terminal.

[0050] In this embodiment, during the excavation process, the drone automatically patrols the excavation site every time a certain distance is excavated (i.e., when the moving distance reaches a preset value), so that the patrol frequency of the drone is related to the construction progress; the take-off, landing and flight of the drone are adaptively controlled according to the construction progress, which reduces the workload of relevant personnel. By effectively monitoring the construction process, it is convenient for managers to understand the construction progress and the specific situation of the construction site in a timely manner.

[0051] The above are merely embodiments of the present invention. The invention is not limited to the fields covered by these embodiments. Commonly known structures and characteristics in the solutions are not described in detail here. Those skilled in the art are aware of all common technical knowledge in the field prior to the application date or priority date, are able to access all existing technologies in that field, and have the ability to apply conventional experimental methods prior to that date. Those skilled in the art can, under the guidance of this application, improve and implement this solution in combination with their own capabilities. Some typical known structures or methods should not be obstacles for those skilled in the art to implement this application. It should be noted that those skilled in the art can make several modifications and improvements without departing from the structure of the present invention. These should also be considered within the scope of protection of the present invention, and will not affect the effectiveness of the implementation of the present invention or the practicality of the patent. The scope of protection claimed in this application should be determined by the content of its claims, and the specific embodiments described in the specification can be used to interpret the content of the claims.

Claims

1. A method for excavating adjacent existing railway trenches using a UAV-based surveying method, characterized in that: Includes the following steps: Plan the flight route: Plan the flight route based on the road cut slope to be excavated; Drone survey: Control the drone to survey the road cut slope to be excavated along the designated flight path; 3D terrain map creation: Extract aerial images captured by the five-lens tilt camera on the drone, as well as the drone's POS data; A three-dimensional topographic map of the cut slope is generated based on aerial images and POS data. Planning: Develop an excavation plan based on the 3D topographic map of the road cut slope; Construction preparation: Reinforce the top of the cut slope to be excavated, and construct surface drainage ditches along the outer side of the new road slope. Erect protective scaffolding: Erect mobile protective scaffolding on the outer side of the slope crest and fixed protective scaffolding on the slope foot; Earthwork excavation in the road cut: Excavate from the side of the new line towards the side of the existing line to form an excavation trench. During excavation, a partition wall is reserved near the side of the existing line, with a top width of 1.8m to 2.2m and a trench depth of 3m to 5m. Move the movable protective frame down the side slope of the existing line and excavate the earthwork of the partition wall section, maintaining a top width of 1.8m to 2.2m. The distance between the top of the partition wall and the bottom of the excavation trench is not less than 2m. Expand the trench depth to 3m to 5m and gradually move the inner sidewall of the partition wall outward until the top width reaches 1.8m to 2.2m. Repeat this process of moving the movable protective frame down, excavating the partition wall earthwork, and expanding the trench until the trench reaches the design elevation. Then, remove the partition wall. Slope protection: Reinforce and protect the slopes of the newly constructed line; The mobile protective frame is horizontally installed with a straight guide rail on the side facing the new line slope. A sliding block is slidably connected to the guide rail. A section arm is hinged to the sliding block. The length of the section arm is 1.8m to 2.2m. A second section arm is hinged to the free end of the section arm. The length of the second section arm is at least 3m. An angle iron is installed on the lower side of the free end of the first arm, and the side of the angle iron facing the second arm is inclined. A rack is mounted on the guide rail, and the rack is parallel to the guide rail. A motor is mounted on the slide, and a gear is connected to the output end of the motor. The gear meshes with the rack. It also includes a secondary rail, on which a secondary slide block is slidably connected, and a rod is hinged to the secondary slide block. A second rod is hinged to the free end of the first rod, and the end of the second rod away from the first rod is hinged to a section arm.

2. The method for excavating adjacent existing railway trenches using UAV mapping based on the wall-type excavation method according to claim 1, characterized in that: During the earthwork excavation of the road cut, the excavation surface of the new line slope shall maintain a longitudinal drainage slope of not less than 4%, a longitudinal drainage ditch shall be provided in the middle of the new line slope, and temporary drainage ditches shall be set on both sides of the excavation trench in the transverse direction.

3. The method for excavating adjacent existing railway trenches using UAV mapping based on claim 2, characterized in that: The excavation slope ratio on the inner side of the partition wall should not be less than 1:0.

2.

4. The method for excavating adjacent existing railway trenches using UAV mapping based on the wall-type excavation method according to claim 1, characterized in that: Several control points were also set up on the road cut slope, and the coordinates of the control points were determined; In the process of creating a 3D topographic map, the coordinates of the 3D topographic map are also calibrated based on the image control points.

5. The method for excavating adjacent existing railway trenches using UAV mapping based on claim 4, characterized in that: It also includes the following steps: Set up a take-off and landing platform: Set up a take-off and landing platform on a flat area near the road cut slope, place the drone on the take-off and landing platform, and set up a control terminal outside the take-off and landing platform; Excavation inspection: A data acquisition module is installed on the slide block. The data acquisition module includes a communication unit, a microprocessor unit, and a Hall sensor that are electrically connected. The Hall sensor counts the number of rotations of the gear. The microprocessor unit calculates the moving distance of the first and second arm sections based on the number of rotations of the gear. The communication unit sends the calculated moving distance to the control terminal. The control terminal receives and records the movement distance of the first and second arm sections. When the movement distance reaches a preset value, it creates an inspection route and sends it to the drone. The drone inspects the excavation work according to the inspection route. During the inspection, the drone takes off from the take-off and landing platform, flies to the front of the road cut slope, performs visual recognition based on the collected images, identifies the mobile protective frame, flies to the top of the mobile protective frame, controls the drone's gimbal to point the camera on the gimbal towards the excavation trench or excavation partition wall, and flies from one end to the other along the length of the mobile protective frame to collect images of the excavation trench or excavation partition wall; finally, it returns and lands on the take-off and landing platform.

6. The method for excavating adjacent existing railway trenches using UAV mapping based on claim 5, characterized in that: In the process of setting up the take-off and landing platform, the five-lens tilt camera on the UAV will be replaced with a monocular camera.

Images