Overhead line section blocking crossing frame and construction method

Abstract

This invention discloses a segmented overhead power line netting crossing frame and its construction method. The segmented overhead power line netting crossing frame includes low-level obstacles, mid-level obstacles, and high-level obstacles. A lower first crossing frame is installed between the low-level and mid-level obstacles, and higher second crossing frames are installed on the outer sides of both types of obstacles. A lower layer of netting is installed between the first crossing frame and one side of the second crossing frame, a mid-level netting is installed between the two sides of the second crossing frames, and a high-level netting is installed between the two high-level obstacles. The lower and mid-level netting are each equipped with independent rope and ground anchoring systems, and the high-level netting is directly fixed to the high-level obstacle. The three layers of netting are isolated from each other and their forces are not interconnected. By setting up independent lower, mid, and high-level netting, each layer of netting is completely isolated from each other and their forces are not interconnected. This invention not only allows for independent adjustment of individual netting sections but also enables separate installation of protective netting for different obstacles, improving work efficiency and reducing on-site adjustment workload.

Description

Technical Field

[0001] This invention relates to a power grid enclosure crossing frame, and more particularly to an overhead line segmented enclosure crossing frame and construction method, belonging to the field of power construction technology. Background Technology

[0002] With the continuous improvement of China's power infrastructure network, high-voltage transmission line corridors inevitably cross various important transportation and power facilities such as high-speed railways, conventional railways, highways, municipal roads, and communication cables. The presence of multiple obstacles with different ownership, control standards, and maintenance windows within the same span has become a common construction condition. Current transmission line crossing netting construction generally adopts a whole-span integrated full-coverage netting process, meaning that only one complete netting system and one anchoring tensioning system are set up within the same obstacle span, and the entire system is erected and dismantled simultaneously. While this traditional technique can meet basic protection requirements in a single obstacle crossing scenario, it has the following drawbacks in continuous crossing situations involving multiple types of obstacles, multiple management units, and inconsistent construction windows: ① Limited construction windows: The entire netting requires all obstacles to be ready for construction simultaneously. If a single facility's skylight fails to meet the requirements, construction cannot proceed, making schedule coordination difficult; ② Inability to adjust locally: The forces on the entire netting are interconnected. If only the protection parameters of a single section need adjustment, the entire netting must be loosened and re-tensioned, which is cumbersome and can easily reduce the safety performance of the netting; ③ Interference from construction with multiple obstacles: When high and low obstacles coexist, a single-layer netting cannot provide layered and zoned protection. The erection, adjustment, and dismantling processes interfere with each other, making on-site safety management difficult; ④ Lack of suitable dedicated structures: Existing crossing technologies are all optimized around an integrated netting system, lacking dedicated netting structures with segmented independent anchoring and staggered construction, making it difficult to adapt to continuous crossing situations with multiple obstacles. Summary of the Invention

[0003] The technical problem to be solved by the present invention is to overcome the shortcomings of the prior art and provide an overhead line segmented netting crossing frame and construction method, so as to achieve complete isolation, independent anchoring, and separate tensioning and disassembly of the low, medium and high three-layer netting, and that the construction of each layer does not interfere with each other, thereby greatly improving the safety and work efficiency of the line crossing construction.

[0004] The technical solution adopted by this invention to solve the technical problem is as follows: An overhead power line segmented enclosure crossing frame includes a low-level obstacle, a middle-level obstacle, and a high-level obstacle. A first crossing frame is provided between the low-level obstacle and the middle-level obstacle. A second crossing frame is provided on the outside of the low-level obstacle and the middle-level obstacle, and a high-level obstacle is provided on the outside of each second crossing frame. A lower layer of enclosure netting is provided between the first crossing frame and the second crossing frame to the right of the low-level obstacle. A middle layer of enclosure netting is provided between the first crossing frame to the left of the middle-level obstacle and the second crossing frame to the right of the low-level obstacle. A higher layer of enclosure netting is provided between the two high-level obstacles.

[0005] The lower, middle, and upper layers of the sealing net are each composed of a Dyneema main rope and a sealing rope.

[0006] The left end of the lower enclosure net is connected to the first crossing frame, and the right end of the lower enclosure net is connected to the second crossing frame on the right side of the low obstacle. Both ends of the lower enclosure net are anchored to the ground by ropes and ground anchors.

[0007] The two ends of the middle layer of the sealing net are respectively connected to the second crossing frame on both sides, and the two ends of the middle layer of the sealing net are anchored to the ground by pull ropes and ground anchors.

[0008] The two ends of the high-rise enclosure net are fixed to high-level obstacles.

[0009] The first crossing frame is lower in height than the second crossing frame and is located below and inside the second crossing frame.

[0010] The lower and middle layers of the sealing net are isolated from each other, and the middle layer of the sealing net covers the lower layer of the sealing net; the upper layer of the sealing net is isolated from the middle layer of the sealing net, and the upper layer of the sealing net covers the middle layer of the sealing net.

[0011] The construction method for segmented netting crossing frames of overhead power lines includes the following steps: S1. Use drones to conduct panoramic surveys of the spatial dimensions of low-level obstacles, mid-level obstacles, and high-level obstacles; use BIM 3D modeling to pre-simulate the spatial layout of the three-layer enclosure net, and separately delineate the independent construction zones and dedicated ground anchor placement points for the lower, middle, and upper layers of the enclosure net. S2. The foundation of the construction site is compacted in layers and a bedding layer is laid for seepage prevention; according to the model dimensions, a first crossing frame with a lower height and a second crossing frame with a higher height are erected; for the lower and middle layers of the netting, separate ground anchors are pre-embedded, and for the high-level netting, independent fixing connectors are provided, so that each layer of netting forms a completely independent anchoring and bearing foundation; after the frame is erected, the grounding resistance is tested, and the netting operation can only be carried out after the acceptance is qualified. S3. During the window period for clearing low-level obstacles, connect the two ends of the Dyneema main rope of the lower-level enclosure net to the first and second crossing frames respectively. Connect the two ends of the main rope to dedicated pull ropes and anchor them to the dedicated ground anchors on the lower level. Fix the enclosure rope to the Dyneema main rope to form a complete net. Adjust the sag of the lower-level enclosure net to the safety standard by tensioning the pull ropes separately. This completes the single-layer protection of low-level obstacles. The entire construction process does not occupy the conditions for the operation of the middle and high-level enclosure nets. S4. Construct the middle layer of the safety net and use another obstacle window separately without removing the lower layer of the safety net; set up the Dyneema main rope of the middle layer of the safety net on the second crossover frame on both sides, connect the middle layer dedicated pull rope to the independent ground anchor, and tension and adjust the sag separately; the middle layer of the safety net is set above the lower layer of the safety net and a safe isolation gap is maintained between the layers to form a double-layer segmented protection for low-level obstacles; S5. Construct a high-rise safety net. After the construction of the low-level obstacles is completed, erect a high-rise safety net between the two high-level obstacles. Fix both ends of the Dyneema main rope of the high-rise safety net to the upper part of the high-level obstacles. The high-rise safety net fully covers the middle and lower layers of the safety net to form a bottom protection. The high-rise safety net does not share the ground anchoring system with the lower and middle layers. S6. After all three layers of netting are in place, overhead conductors are laid out, tightened, and accessories are installed. If the protection requirements of a single area change during the construction process, only the tension of the single layer of netting is adjusted accordingly. The anchoring and netting structure of the other two layers of netting remain unchanged, and there is no need to remove the netting as a whole. S7. After the line construction and acceptance are completed, the netting shall be dismantled in layers in the order of high-level netting - middle-level netting - lower-level netting. When dismantling any layer, the Dyneema main rope, guy rope and ground anchor of the other two layers of netting shall remain anchored and locked, and shall not sink, shift or become unstable. After the netting of a single layer is dismantled, the Dyneema main rope and netting rope of that layer shall be recovered. After all the netting is dismantled, the second crossing frame and the first crossing frame shall be dismantled in sequence, all ground anchors shall be recovered, and the construction site shall be leveled and restored.

[0012] The positive and beneficial effects of this invention are: 1. This invention sets up independent lower, middle, and upper layers of protective netting, with each layer of netting completely isolated from the others and not interfering with each other. This allows for adjustments to the netting in each area without the need for overall loosening and re-pulling. At the same time, it also enables the separate installation of protective netting for different obstacles through staggered skylights, improving work efficiency and reducing on-site adjustment workload.

[0013] 2. This invention uses a combination of first and second crossing frames with varying heights to support and deploy multi-layered protective netting, achieving zoned isolation and protection for low, medium, and high-level obstacles. Independent safety gaps are formed between layers, completely avoiding mutual interference between multi-layered protective operations. This constructs a multi-layered bottom protection structure, effectively avoiding the risks of falling wires and falling foreign objects, and improving the safety of construction in complex obstacle-crossing conditions.

[0014] 3. This invention adopts a split anchoring structure with high-level support for obstacles and independent ground anchors in the middle and lower layers. Each layer of the anchoring system is completely independent and does not share the same anchoring system, which effectively distributes the overall wind load and reduces the consumption of anchoring materials and construction investment. At the same time, it can realize layered reverse dismantling. When dismantling a single layer of netting, the remaining netting continues to provide bottom protection, with no protection gaps throughout the process, further ensuring construction safety. Attached Figure Description

[0015] Figure 1 This is a schematic diagram of the structure of the present invention; Among them: 1-low-level obstacle, 2-middle-level obstacle, 3-high-level obstacle, 4-first crossing frame, 5-second crossing frame, 6-lower-level netting, 7-middle-level netting, 8-high-level netting. Detailed Implementation

[0016] The invention will be further explained and described below with reference to the accompanying drawings: Example 1, see Figure 1 A segmented overhead line enclosure crossing frame includes a low-level obstacle 1, a middle-level obstacle 2, and a high-level obstacle 3. A first crossing frame 4 is provided between the low-level obstacle 1 and the middle-level obstacle 2. Second crossing frames 5 are provided on the outside of the low-level obstacle 1 and the middle-level obstacle 2, and a high-level obstacle 3 is provided on the outside of each second crossing frame 5. A lower layer enclosure 6 is provided between the first crossing frame 4 and the second crossing frame 5 on the right side of the low-level obstacle 1. A middle layer enclosure 7 is provided between the first crossing frame 4 on the left side of the middle-level obstacle 2 and the second crossing frame 5 on the right side of the low-level obstacle 1. A high layer enclosure 8 is provided between the two high-level obstacles 3.

[0017] The lower layer of the sealing net 6, the middle layer of the sealing net 7, and the upper layer of the sealing net 8 are each composed of the Dyneema main rope and the sealing net rope.

[0018] The lower enclosure net 6 is connected to the first crossing frame 4 at its left end and to the second crossing frame 5 on the right side of the low obstacle 1 at its right end. The lower enclosure net 6 is anchored to the ground at both ends by ropes and ground anchors.

[0019] The two ends of the middle layer netting 7 are connected to the second spanning frame 5 on both sides respectively, and the two ends of the middle layer netting 7 are anchored to the ground by ropes and ground anchors.

[0020] The two ends of the high-rise enclosure net 8 are fixed to the high-level obstacle 3. The high-rise enclosure net is directly locked to the top of the steel structure of the high-level obstacle, without occupying ground anchor resources.

[0021] The first gantry 4 is lower in vertical height than the second gantry 5 and is located below and inside the second gantry 5.

[0022] The lower layer of the sealing net 6 and the middle layer of the sealing net 7 are isolated from each other, and the middle layer of the sealing net 7 covers the lower layer of the sealing net 6; the upper layer of the sealing net 8 and the middle layer of the sealing net 7 are isolated from each other, and the upper layer of the sealing net 8 covers the middle layer of the sealing net 7.

[0023] In the above description, the middle layer of the sealing net is arranged above the lower layer of the sealing net, with a 1.2m safety isolation gap reserved between the two layers; the upper layer of the sealing net is arranged above the middle layer of the sealing net, with a 1.5m isolation gap reserved between the layers, and the three layers of nets are not in contact and are completely independent in terms of force. Example 2, the construction method of the above-mentioned overhead line segmented enclosure and crossing frame includes the following steps: S1. Use drones to conduct panoramic surveys of the spatial dimensions of low-level obstacle 1, middle-level obstacle 2, and high-level obstacle 3; use BIM 3D modeling to pre-simulate the spatial layout of the three-layer enclosure net, and separately delineate the independent construction zones and dedicated ground anchor placement points for the lower, middle, and upper layers of the enclosure net. S2. The foundation of the construction site is compacted in layers and a bedding layer is laid for seepage prevention; according to the model dimensions, the first crossing frame 4 with a lower height and the second crossing frame 5 with a higher height are erected; for the lower and middle layers of the netting, separate ground anchors are pre-embedded, and the high-level netting is equipped with independent fixed connecting parts, so that each layer of netting forms a completely independent anchoring and bearing foundation; after the frame is erected, the grounding resistance is tested, and the netting operation can only be carried out after the acceptance is qualified. S3. During the window period for low-level obstacles, connect the two ends of the Dyneema main rope of the lower layer netting 6 to the first crossing frame 4 and the second crossing frame 5 respectively. Connect the two ends of the main rope to dedicated pull ropes and anchor them to the dedicated ground anchors on the lower layer. Fix the netting ropes to the Dyneema main ropes to form a complete net. Adjust the sag of the lower layer netting to the safety standard by tensioning the pull ropes separately. This completes the single-layer protection of low-level obstacles. The construction process does not occupy the conditions for the operation of the middle and high-level netting. S4. Construct the middle layer of the barrier netting and activate another obstacle skylight separately without removing the lower layer barrier netting 6; erect the Dyneema main rope of the middle layer barrier netting 7 on the second cross-frame 5 on both sides, connect the middle layer dedicated pull rope to the independent ground anchor, and tension and adjust the sag separately; the middle layer barrier netting 7 is set above the lower layer barrier netting 6 and a safe isolation gap is maintained between the layers to form a double-layer segmented protection for low-level obstacles; S5. Construct a high-rise safety net. After the construction of the low-level obstacle 1 is completed, erect a high-rise safety net 8 between the two high-level obstacles 3. Fix both ends of the Dyneema main rope of the high-rise safety net 8 to the upper part of the high-level obstacle 3. The high-rise safety net 8 fully covers the middle and lower layers of the safety net to form a bottom protection. The high-rise safety net does not share the ground anchoring system with the lower and middle layers. S6. After all three layers of netting are in place, overhead conductors are laid out, tightened, and accessories are installed. If the protection requirements of a single area change during the construction process, only the tension of the single layer of netting is adjusted accordingly. The anchoring and netting structure of the other two layers of netting remain unchanged, and there is no need to remove the netting as a whole. S7. After the line construction and acceptance are completed, the netting shall be dismantled in layers in the order of high-level netting → middle-level netting → lower-level netting. When dismantling any layer, the Dyneema main rope, guy rope and ground anchor of the other two layers of netting shall remain anchored and locked, and shall not sink, shift or become unstable. After the single layer of netting is dismantled, the Dyneema main rope and netting rope of that layer shall be recovered. After all the netting is dismantled, the second crossing frame 5 and the first crossing frame 4 shall be dismantled in sequence, all ground anchors shall be recovered, and the construction site shall be leveled and restored.

[0024] This invention employs a core structural design combining layered and segmented independent protective netting with separate, dedicated anchoring. Utilizing staggered first and second crossing frames, it divides the area into three isolated protective zones: a lower, middle, and upper layer. Each layer of netting has its own independent tensioning and anchoring system, ensuring no coupling or interference between layers. During construction, staggered layered installation and individual tensioning and adjustment can be implemented based on varying maintenance windows for different obstacles, without requiring all crossed facilities to simultaneously meet construction conditions. During conductor deployment, only a single layer of netting needs adjustment to correct local protection parameters, while the remaining layers maintain a locked and stable state. At the end of construction, the netting is dismantled layer by layer in reverse order from top to bottom. When any single layer is removed, the remaining netting continues to provide backup protection, eliminating any protective gaps. This segmented isolation, independent force distribution, and time-sharing construction mechanism overcomes the shortcomings of traditional integrated netting systems, such as overall interconnectedness, limited construction windows, and interference between dismantling and adjustments.

[0025] This invention utilizes a layered independent netting system and a separate anchoring structure to achieve independent adjustment of individual netting sections, simplifying on-site adjustment procedures, fully utilizing scattered construction windows for different obstacles, and improving construction efficiency and process flexibility in complex multi-obstacle crossing scenarios. Furthermore, it leverages the layered deployment of high and low frames to form multi-layered isolation and bottom protection, avoiding interference between multiple construction operations. Combined with a layered reverse dismantling method, it eliminates safety gaps during dismantling. Simultaneously, the separate anchoring structure can distribute the overall wind load and reduce investment in anchoring materials, thereby lowering construction material costs while ensuring safety throughout the obstacle-crossing construction process. This invention is suitable for complex continuous overhead line crossing construction conditions.

Claims

1. An overhead line sectioning fence crossing support comprising a low barrier (1), a middle barrier (2) and a high barrier (3), characterized in that: A first crossing frame (4) is provided between the low obstacle (1) and the middle obstacle (2). A second crossing frame (5) is provided on the outside of the low obstacle (1) and the middle obstacle (2). A high obstacle (3) is provided on the outside of each second crossing frame (5). A lower layer netting (6) is provided between the first crossing frame (4) and the second crossing frame (5) on the right side of the low obstacle (1). A middle layer netting (7) is provided between the first crossing frame (4) on the left side of the middle obstacle (2) and the second crossing frame (5) on the right side of the low obstacle (1). A high layer netting (8) is provided between the two high obstacles (3).

2. An overhead line sectionalisati on crossing support accordin g to claim 1, characterized in that: The lower sealing net (6), middle sealing net (7), and upper sealing net (8) are respectively composed of Dyneema main rope and sealing net rope.

3. An overhead line sectionalisati on crossing support accordin g to claim 1, characterized in that: The left end of the lower sealing net (6) is connected to the first crossing frame (4), and the right end of the lower sealing net (6) is connected to the second crossing frame (5) on the right side of the low obstacle (1). Both ends of the lower sealing net (6) are anchored to the ground by ropes and ground anchors.

4. An overhead line sectionalizing fence crossing according to claim 1, characterized in that: The two ends of the middle layer sealing net (7) are respectively connected to the second cross-bridge frame (5) on both sides, and the two ends of the middle layer sealing net (7) are anchored to the ground by pull ropes and ground anchors.

5. An overhead line sectionalizing closure span according to claim 1, wherein: The two ends of the high-rise enclosure net (8) are fixed to the high-level obstacle (3).

6. An overhead line sectionalizing fence crossing according to claim 1, wherein: The first crossing frame (4) is lower in height than the second crossing frame (5) and is located at the lower inner side of the second crossing frame (5).

7. An overhead line sectionalizing fence crossing according to claim 1, characterized in that: The lower sealing net (6) is isolated from the middle sealing net (7), and the middle sealing net (7) covers the lower sealing net (6); the upper sealing net (8) is isolated from the middle sealing net (7), and the upper sealing net (8) covers the middle sealing net (7).

8. The construction method of an overhead line section dead-end crossing according to any one of claims 1 to 7, characterized in that, Includes the following steps: S1. Use drones to conduct panoramic surveys of the spatial dimensions of low-level obstacles (1), middle-level obstacles (2), and high-level obstacles (3); use BIM three-dimensional modeling to pre-simulate the spatial layout of the three-layer enclosure net, and separately delineate the independent construction zones and exclusive ground anchor placement points for the lower-level enclosure net, middle-level enclosure net, and upper-level enclosure net. S2. The foundation of the construction site is compacted in layers and a cushion layer is laid for seepage prevention; according to the model size, the first crossing frame (4) with a lower height and the second crossing frame (5) with a higher height are erected; for the lower layer netting and the middle layer netting, the ground anchors that are not shared are pre-embedded separately, and the high-level netting is equipped with independent fixed connecting parts, so that each layer of netting forms a completely independent anchoring and bearing foundation; after the frame is erected, the grounding resistance is tested, and the netting operation can only be carried out after the acceptance is qualified; S3. During the window period for low-level obstacles, connect the two ends of the Dyneema main rope of the lower layer netting (6) to the first crossing frame (4) and the second crossing frame (5) respectively. Connect the two ends of the main rope to the dedicated pull rope and anchor them to the lower layer dedicated ground anchor. Fix the netting rope to the Dyneema main rope to form a complete net. Tensile the pull rope separately to adjust the sag of the lower layer netting to the safety standard, and complete the single-layer protection of low-level obstacles. The construction process does not occupy the conditions for the operation of the middle and high-level netting. S4. Construct the middle layer of the barrier net and use another obstacle skylight separately without removing the lower layer barrier net (6); erect the Dyneema main rope of the middle layer barrier net (7) on the second cross frame (5) on both sides, connect the middle layer exclusive pull rope and independent ground anchor, and tension and adjust the sag separately; the middle layer barrier net (7) is set above the lower layer barrier net (6) and a safe isolation gap is maintained between the layers to form a double-layer segmented protection for low-level obstacles; S5. After the construction of the low obstacle (1) is completed, a high-rise net (8) is erected between the two high obstacles (3). The two ends of the Dyneema main rope of the high-rise net (8) are fixed to the upper part of the high obstacle (3). The high-rise net (8) fully covers the middle and lower layers of nets to form a bottom protection. The high-rise net does not share the ground anchoring system with the lower and middle layers. S6. After all three layers of netting are in place, overhead conductors are laid out, tightened, and accessories are installed. If the protection requirements of a single area change during the construction process, only the tension of the single layer of netting is adjusted accordingly. The anchoring and netting structure of the other two layers of netting remain unchanged, and there is no need to remove the netting as a whole. S7. After the line construction and acceptance are completed, the netting is dismantled in layers in the order of high-level netting - middle-level netting - lower-level netting. When any layer is dismantled, the Dyneema main rope, guy rope and ground anchor of the other two layers of netting are kept anchored and locked, and there will be no sinking, displacement or instability. After the single-layer netting is dismantled, the Dyneema main rope and netting rope of that layer are recovered. After all the netting is dismantled, the second crossing frame (5) and the first crossing frame (4) are dismantled in sequence, all ground anchors are recovered, and the construction site is leveled and restored.

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