All-steel-pipe space truss structure framework of 1000kV transformer substation and construction method of all-steel-pipe space truss structure framework

Abstract

The invention discloses an all-steel-pipe space truss structure framework of a 1000kV transformer substation and a construction method of the all-steel-pipe space truss structure framework. A mounting framework comprises framework columns and framework beams. The construction method comprises the steps of construction site planning, segmented assembly, environment-friendly spraying, hoisting process and bolt control. The construction efficiency and safety are remarkably improved through the framework segmented modular design, the intelligent hoisting technology and the green construction technology, the crawler crane main hoisting and truck crane tail slipping cooperative operation is adopted, and precise installation under the complex working condition is achieved in combination with BIM dynamic simulation; the Internet of Things torque monitoring system is adopted to track the presence time of bolts and components, and the shutdown and material waiting phenomena are reduced; a mechanical collaborative operation system is adopted, and parameterization design is conducted on cooperative operation of a main crane and a tailing crane; the intelligent quality control technology is adopted, real-time uploading and tracing of construction data are achieved, wide industrial application value is achieved, and an innovative solution is provided for extra-high voltage power grid construction.

Description

Technical Field

[0001] The invention relates to a transformer substation installation frame, in particular to a full steel tube space truss structure frame of a 1000kV transformer substation and a construction method thereof, belonging to the technical field of high-voltage power transmission and transformation engineering. Background Art

[0002] With the rapid development of UHV power grid, 1000kV substations, as the core nodes of power transmission, need to withstand extremely high mechanical and electrical loads. Traditional substation structures are mostly made of concrete or ordinary steel structures, which have problems such as long construction period, high risk of high-altitude operations, and difficult precision control. Especially when hoisting large structures, existing technologies often lead to low efficiency due to unreasonable segmentation or improper mechanical selection, and even cause safety accidents.

[0003] Especially for 1000kV UHV substations, the structure needs to withstand greater mechanical loads and complex electromagnetic environments. Conventional construction methods face the following challenges:

[0004] 1) During the installation of the 1000kV frame, the 1000kV high-voltage area and relay room are at the peak of civil construction, and there is cross-operation. The construction site left for frame assembly and placement is limited. In addition to serious cross-operation, the crane position is limited, which increases the difficulty of lifting. It is necessary to rationally plan the lifting area and take protective measures to avoid the impact of cross-operation; the steel truss has a complex structure, large tonnage, large span, and high assembly technology and precision requirements;

[0005] 2) The beams and columns are connected by bolts, the main material is connected by flanges, and the auxiliary materials and the main materials are connected by two symmetrical flat steel plates. The bolts at the connection are dense, and the assembly of the frame columns and steel trusses is difficult. Strict control must be carried out on the overall deformation control and accuracy. The weight of a single rod is too heavy to be easily moved by manpower, and a crane must be used for operation, which brings certain difficulties to the assembly. The frame column is a rectangular variable-section steel pipe lattice structure with a complex structure and greater difficulty in assembly. A lightning rod is installed on the top of the column;

[0006] 3) The 1000kV frame column and steel truss beam are installed in an embedded rigid connection. The distance between the beam end and the column section is small, the frame beam is difficult to put in place, the frame hoisting assembly is a level 3 risk, the high-altitude operation safety risk is high, and the frame installation construction technology, quality process and finished product protection requirements are high;

[0007] 4) The existing construction methods have obvious deficiencies in quality control, environmental protection and cross-operation coordination. Summary of the invention

[0008] The object of the present invention is to provide a fully steel pipe space truss structure framework for a 1000 kV substation and its construction method to solve at least one of the above technical problems. By optimizing the framework section design, innovating the hoisting process and intelligent management means, the problems such as high risk, low efficiency and difficult quality control in traditional construction are solved, and at the same time, green construction and resource conservation are realized.

[0009] The present invention realizes the above object through the following technical solutions: a fully steel pipe space truss structure framework for a 1000 kV substation, including framework columns and framework beams. The framework columns are vertically and fixedly connected to the foundation, and the framework beams are horizontally and fixedly connected between two frameworks.

[0010] The framework columns include a bottom section framework column, a middle section framework column and a top section framework column arranged in sequence from bottom to top. The butt joints of the framework columns are connected by flange plates and bolts. The two ends of the framework beams are fixedly connected to the column body of the middle section framework column by bolts. A lightning rod is connected to the top of the top section framework column. The connection node between the framework column and the framework beam is an embedded rigid connection, and stiffening rib plates are arranged at the node. Double-sided groove welding is used for welding.

[0011] As a further scheme of the present invention: the framework column is a fully steel pipe space truss structure, the framework beam is a rectangular section lattice beam, and the flange plate connection between the framework column and the framework beam is reinforced by symmetric flat steel plates.

[0012] As a further scheme of the present invention: a ladder and a rest platform are arranged at the interface of each section of the framework column. Cage guards are fixedly connected to both sides of the ladder by bolts, and platform gratings are fixedly laid on the rest platform by bolts.

[0013] As a further scheme of the present invention: anchor bolts are embedded in the foundation, double nuts are screwed on the anchor bolts, and gaskets are sleeved on the anchor bolts.

[0014] A construction method for a fully steel pipe space truss structure framework of a 1000 kV substation, the construction method includes the following steps:

[0015] S1. Construction site planning: The construction site is divided into areas, which are respectively divided into: a ground assembly area, a crane occupancy area and a material transportation passage, and each of the divided sites is processed and accepted.

[0016] S2, segmented assembly: the ground assembly of the bottom frame column, the middle frame column and the top frame column of the frame column and the ground assembly of the frame beam are respectively carried out. Each frame column section of the frame column is composed of a number of steel pipe welded section columns. Timbers are laid on the ground as pads. For the ground assembly of each frame column section, the section column is placed on the pads, and the flanges of the adjacent section columns are calibrated by a laser centering instrument to align the flange holes of the adjacent section column flanges. Bolts are passed through the aligned flange holes and tightened symmetrically three times using a hydraulic torque wrench. Ladders and rest platforms are installed for each assembled section of the frame column; for the ground assembly of the frame beam, pre-arch control is carried out, and the pre-arch is set according to the span of 1 / 500. A hydraulic jack is used for lifting and adjustment, and a total station is used for real-time monitoring. The main material bolts are inserted from the center to both ends, and the auxiliary material bolts are inserted from the inside to the outside, with an exposed length of 2-3 threads;

[0017] S3, Environmentally friendly spraying: After the frame columns and beams of the frame are assembled, sea grey 919 paint is sprayed on the ground. Layered spraying is adopted, and anti-fouling colored strips are laid in the spraying area;

[0018] S4. Hoisting process: During the hoisting construction, the columns of each section of the frame are first hoisted in groups by the combination of the main hoist and the tail crane. The main hoist uses a 260t crawler crane and the tail crane uses an 80t truck crane. After the installation of the bottom section of the frame column is completed, all the anchor bolts are tightened in time. After the anchor bolts are tightened, the temporary grounding wire is installed in time. After the installation of the bottom section of the frame column above the foundation is completed, the geometric dimensions of the frame column are re-measured with a total station. After that, the geometric dimensions of each section of the frame column are re-measured. The column foot is adjusted with a jack or a track hoist, and the upper part of the frame column is corrected with a rope. After the frame is hoisted, the frame beam is tied at four points + single machine hoisted. The frame beam is hoisted by the four-point tying method, and the frame beam is hoisted to the middle section of the frame column area and fixed with bolts;

[0019] S5. Bolt control: The IoT torque monitoring system is used to upload bolt tightening data to the management platform in real time. The sensor collects torque value, bolt number and operator information. The collected information data is encrypted by the gateway and uploaded to the cloud. The platform automatically compares the design value, and triggers an audible and visual alarm and SMS notification when the deviation is ≥10%.

[0020] As a further solution of the present invention: In S1, for the ground assembly area, the GIS area is used as the ground assembly site of the frame, and the site is divided into a component stacking area, an assembly area and a spraying area, and the distance between each area is ≥5m, and a hard fence and warning signs are set;

[0021] For the crane occupation area, the width of the main crane route is ≥8m, and the turning radius is ≥12m; the foundation bearing capacity of the tail crane station is ≥200kPa, and a roadbed box is laid when necessary;

[0022] For the material transportation passage: Utilize the existing roads within the station, with a width ≥ 6m, a slope ≤ 5%, and the road surface is hardened with C30 concrete;

[0023] The treatment and acceptance of each site specifically include:

[0024] The foundation is compacted. For soft soil layers, replacement filling is carried out, and an 18t roller is used for layered compaction, with a compaction degree ≥ 95%;

[0025] Dig a drainage system, excavate drainage ditches along the perimeter of the site, and connect them to the rainwater pipe network in the station area.

[0026] As a further solution of the present invention: In S2, when assembling the frame beam, it specifically includes the following steps:

[0027] Conduct on-site measurement of the center point of the beam to prevent the beam from being assembled off-center. When assembling, first complete the assembly of the bottom beam of the beam and then install the upper part of the steel truss beam;

[0028] When assembling the frame beam, assemble it on the ground according to the pre-arch value of the beam, and use a level to measure the pre-arch value; Place one piece of sleeper every 5 meters from the center of the sleeper position to both sides, and at the same time, the heights of the sleepers supported on both sides of the flange decrease in sequence;

[0029] When assembling the beam, follow the assembly procedure of first the lower chord and then the upper chord, and first the main materials and then the auxiliary materials. During assembly, strictly control the geometric dimensions, and the steel truss beam walkway is assembled together with the steel truss beam;

[0030] The main bolts of the steel truss beam are inserted from the center to both ends, and the remaining bolts are inserted from the inside of the steel truss beam to the outside of the steel truss beam.

[0031] As a further solution of the present invention: In S4, the hoisting of each section of the frame column specifically includes:

[0032] Hoisting of the bottom section of the frame column: The main hook is hung on the top node, 2 steel wires are used, and the tailing hook is hung on the bottom node, and 2 nylon slings are used; After lifting 100mm off the ground, it is left static for 10 minutes to check whether the crane outriggers settle and whether the steel wire ropes are stressed evenly; After aligning the column foot of the bottom section of the frame column with the anchor bolts, use a jack to adjust the verticality and finally tighten the anchor bolts;

[0033] Hoisting of the middle section of the frame column: The main crane slowly lifts, and the tailing crane cooperates with the rotation. The butt joint gap ≤ 3mm, and insert a temporary positioning pin; Tighten the bolts in the order of "from bottom to top, symmetrically tightening". After final tightening, remove the positioning pin and install a temporary diagonal brace; Use a theodolite for detection, and readjust when the deviation exceeds 20mm;

[0034] Hoisting of the top section of the frame column: Use a laser locator to calibrate the installation angle of the lightning rod, and install a lock washer after final tightening of the bolts; The base of the lightning rod and the column top are welded with double-sided bevel welding, and 100% UT inspection is carried out after welding;

[0035] The hoisting of the frame beam specifically includes:

[0036] Lifting lugs are set at 1 / 4 of the span from the beam end as lifting points. The material of the lifting lugs is Q345B with a thickness of 30 mm. Adjustable lifting lugs are provided at both ends of the H-shaped steel balance beam, and a counterweight of 3 t is used to offset the wind load. After lifting 500 mm above the ground, the deflection of the beam body is measured. If it exceeds L / 500, the hoisting is suspended and reinforced. After the beam end is in place, steel diagonal braces are installed as temporary supports, and a hand-operated hoist is used to adjust the levelness of the beam body. A wireless torque wrench is used to tighten the bolts according to the design value, and the data is uploaded to the management platform in real time. A total station is used to check whether the axis deviation of the beam body is ≤ 5 mm. If it exceeds the tolerance, the bolts are loosened and repositioned.

[0037] As a further solution of the present invention: In S3, the process parameters of the environmental protection spraying include: spraying pressure 0.4 - 0.6 MPa, the distance between the spray gun and the surface of the component is 300 - 500 mm; the dry film thickness of the coating is ≥ 150 μm or ≥ 125 μm; the waste gas treatment uses an activated carbon adsorption tower, and the VOC removal rate is ≥ 90%;

[0038] In S5, the Internet of Things torque monitoring system includes: a wireless torque sensor, a LoRa gateway, and a cloud management platform.

[0039] As a further solution of the present invention: The construction method further includes: a progress dynamic adjustment mechanism, safety risk control measures, and waste management measures, specifically including:

[0040] The progress dynamic adjustment mechanism simulates the construction progress based on the BIM + GIS platform, and updates the data of material arrival, mechanical occupancy, and personnel allocation daily; if the material delay is ≥ 3 days, start the alternative supplier and adjust the hoisting sequence, and give priority to installing the frame sections that are not affected; if encountering bad weather, convert the high-altitude operation to ground assembly and enable the emergency material inventory;

[0041] The safety risk control measures use the LEC method for risk assessment. For level 4 risk operations, the project manager needs to issue a "red ticket", and for level 3 risk operations, the safety officer shall be on site throughout the process; high-altitude operation personnel are equipped with double-hook safety belts, vertical climbing self-locking devices, and anti-falling devices, and the tensile strength of the self-locking device rope is ≥ 22 kN; hard fences and audible and visual warning devices are set in the hoisting area, and non-operating personnel are prohibited from entering within a radius of 30 m;

[0042] For the waste management measures, waste paint buckets and galvanized slag are stored separately in sealed containers and handed over to a hazardous waste treatment qualified unit for disposal; the recovery rate of wire ropes and bolt packages is ≥ 95%, and the metal waste is crushed and used for subgrade filling; the construction wastewater is treated by a three-stage sedimentation tank and discharged with the pH value controlled within the range of 6 - 9.

[0043] The beneficial effects of the present invention are:

[0044] 1) The present invention significantly improves construction efficiency and safety through segmented modular design of the frame, intelligent lifting process and green construction technology. It uses a 260t crawler crane as the main crane and an 80t truck crane as the tail crane for collaborative operation, combined with BIM dynamic simulation, to achieve precise installation under complex working conditions;

[0045] 2) The present invention adopts segmented optimization and modular construction. By dividing the frame column into three sections for ground assembly and segmented hoisting, compared with the traditional section-by-section hoisting, it can effectively reduce high-altitude operations and reduce operational safety risks, while effectively improving the hoisting work efficiency;

[0046] 3) The present invention uses the Internet of Things torque monitoring system to track the arrival time of bolts and components, and the on-time rate of material supply is increased from 78% to 95%, reducing the phenomenon of downtime waiting for materials. It adopts a mechanical collaborative operation system, and the main tail crane cooperates with the parametric design of the operation, the load rate is controlled below 85%, and the safety is improved by 30%. It adopts intelligent quality control technology to achieve real-time uploading and tracing of construction data. Based on green construction technology, the ground spraying process reduces VOC emissions by 60%, and the waste material recovery rate is ≥95%;

[0047] 4) The present invention achieves comprehensive improvement in efficiency, quality, safety and environmental protection through modular design, intelligent hoisting and integrated control. Its technical effect is significantly better than traditional processes, has wide industrial application value, and provides an innovative solution for the construction of UHV power grids. BRIEF DESCRIPTION OF THE DRAWINGS

[0048] Figure 1 This is a schematic diagram of the overall structure of the installation frame of the present invention;

[0049] Figure 2 This is a schematic diagram of the structure of the frame column of the present invention in a split state;

[0050] Figure 3 It is a schematic diagram of the construction process of the present invention;

[0051] Figure 4 This is a schematic diagram of the sequence of hoisting the frame columns of the present invention;

[0052] Figure 5 This is a schematic diagram of the hoisting of the frame column of the present invention;

[0053] Figure 6 This is a schematic diagram of the hoisting of the frame beam of the present invention;

[0054] Figure 7 This is a schematic diagram of the force on the tail crane of the present invention;

[0055] Figure 8 This is a schematic diagram of the calculation of the tail-slip sling of the present invention;

[0056] Figure 9Schematic diagram of the forces on the main hoist of the present invention in the hoisted state;

[0057] In the figure: 1, framework column; 11, bottom section framework column; 12, middle section framework column; 13, top section framework column; 14, lightning rod; 2, framework beam. Specific implementation manner

[0058] Next, the technical solutions in the embodiments of the present invention will be clearly and completely described in conjunction with the accompanying drawings in the embodiments of the present invention. Obviously, the described embodiments are only a part of the embodiments of the present invention, rather than all the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative efforts shall fall within the protection scope of the present invention.

[0059] Embodiment 1, as Figures 1 to 2 shown, a full-steel pipe space truss structure framework of a 1000 kV substation includes a framework column 1 and a framework beam 2. The framework column 1 is vertically fixedly connected to the foundation, and the framework beam 2 is horizontally fixedly connected between two framework columns 1;

[0060] The framework column 1 includes a bottom section framework column 11, a middle section framework column 12, and a top section framework column 13 arranged in sequence from bottom to top. The butt joints of the framework column 1 are connected by flange plates and bolts. The two ends of the framework beam 2 are fixedly connected to the column body of the middle section framework column 12 by bolts. A lightning rod 14 is connected to the top end of the top section framework column 13. The connection node between the framework column 1 and the framework beam 2 is an embedded rigid connection, and stiffening rib plates are provided at the node. The thickness of the rib plates is ≥16 mm, and double-sided groove welding is used for welding, and the weld quality grade is grade I.

[0061] The framework column 1 is a full-steel pipe space truss structure, and the framework beam 2 is a rectangular cross-section lattice beam. The flange plate connection between the framework column 1 and the framework beam 2 is reinforced with symmetric flat steel plates. It should be noted that the steel pipe material of the framework column 1 is Q355B, the steel plate and section steel material are Q235B, the thickness of the flat steel plate is ≥20 mm, and the bolt hole spacing error is ≤2 mm.

[0062] Ladders and rest platforms are provided at the interfaces of each section of the framework column 1. Cage guards are fixedly connected to both sides of the ladders by bolts, and platform gratings are fixedly laid on the rest platforms by bolts. It should be noted that the height of the cage guards of the ladders is ≥1.2 m, the model of the platform gratings is G255 / 30-100, and the bolt grade is 6.8.

[0063] Anchor bolts are pre-embedded in the foundation. Double nuts are screwed on the anchor bolts, and gaskets are sleeved on the anchor bolts so as to realize the fixed connection between the foundation and the bottom end of the framework column 1 through the anchor bolts to ensure the stability of the framework column 1 after installation. It should be noted that the thread length deviation of the anchor bolts is ≤10 mm, the length deviation of the part exposed above the foundation surface is ≤5 mm, and molybdenum disulfide lubricant is applied between the nuts and the gaskets.

[0064] Example 2, as Figures 3 to 6 shown, a construction method for a fully steel pipe space truss structure framework of a 1000 kV substation, including installing the framework in Example 1, the construction method comprising the following steps:

[0065] S1. Construction site planning: Divide the construction site into areas, which are respectively divided into: a ground assembly area, a crane occupancy area, and a material transportation passage, and process and accept each of the divided sites. Use the GIS area as the ground assembly and crane occupancy site, harden the crane walking route, and the turning radius ≥ 12 m;

[0066] S2. Sectional assembly: Conduct the ground assembly of the bottom section column 11, middle section column 12, and top section column 13 of the framework column 1 and the ground assembly of the framework beam 2 respectively. Each section column of the framework column 1 is composed of several joint columns welded by steel pipes. Lay sleepers on the ground as supports. For the ground assembly of each section column of the framework column 1, place the joint column on the support, use a laser alignment instrument to calibrate the flange plates of adjacent joint columns to align the flange holes of adjacent joint columns, pass bolts through the aligned flange holes, and use a hydraulic torque wrench to tighten symmetrically in three times. Install ladders and rest platforms for each assembled section column; for the ground assembly of the framework beam 2, control the pre-camber, set the pre-camber according to 1 / 500 of the span, use a hydraulic jack (20 t) to lift and adjust, and use a total station to monitor in real time. The main material bolts are inserted from the center to both ends, and the auxiliary material bolts are inserted from the inside to the outside, with the exposed thread length of 2 - 3 threads. It should be noted that the specifications of the sleepers are 60×40×800 mm, the spacing ≤ 5 m, the elevation deviation of the support surface formed by the sleepers ≤ 3 mm; the hole distance deviation of the flange plate ≤ 2 mm, and the bolt penetration rate is 100%; the initial tightening torque of the bolt is 70% of the final tightening value (such as the initial tightening of M48 bolt is 340 N·m and the final tightening is 500 N·m), the verticality deviation of the ladder ≤ 1‰, the levelness of the platform grating (G255 / 30 - 100) after installation ≤ 3 mm / m, the center deviation of the wire hanging plate of the steel truss beam ≤ 6 mm, and the bending deflection ≤ L / 1000 (L is the span);

[0067] S3. Environmentally friendly spraying: After the assembly of each section column of the framework column 1 and the framework beam 2, spray the sea gray 919 paint on the ground. When spraying, use layered spraying, and lay anti-pollution colored strip cloth in the spraying area;

[0068] S4. Hoisting Process: During hoisting construction, first, each section of the frame column 1 is grouped and hoisted by combining the main hoist and the tailing hoist. The main hoist selects a 260t crawler crane, and the tailing hoist selects an 80t truck crane. After the installation of the bottom section of the frame column 11 is completed, all anchor bolts are promptly tightened. (The tightening tool is an open-end plum blossom wrench welded and extended with a steel pipe that matches the anchor bolt nut), and after tightening, it is rechecked with a torque wrench. After the anchor bolts are tightened, temporary grounding wires are installed in a timely manner. After the installation of the bottom section of the frame column 11 above the foundation is completed, the geometric dimensions of the frame column are rechecked with a total station. Thereafter, the geometric dimensions are rechecked every time a section of the frame column is installed. The column foot of the frame column is adjusted with a jack or a track lifting machine, and the upper part of the frame column is corrected with a rope. After the hoisting of the frame column 1 is completed, the frame beam 2 is hoisted by four-point binding + single-crane hoisting. The frame beam 2 is hoisted by the four-point binding method, and the included angle between the sling and the frame beam 2 is 45° - 60°. The frame beam 2 is hoisted to the area of the middle section of the frame column 12 and fixed and connected by bolts;

[0069] S5. Bolt Control: An Internet of Things torque monitoring system is adopted to upload the bolt tightening data to the management platform in real time. The sensor collects the torque value, bolt number, and operator information; the collected information data is encrypted by the gateway and then uploaded to the cloud; the platform automatically compares with the design value, and when the deviation ≥ 10%, an audible and visual alarm and a text message notification (to the management personnel) are triggered.

[0070] Furthermore, in S1, for the ground assembly area, the GIS area is used as the ground assembly site for the frame, with an area of not less than 2000m 2 , and the bearing capacity ≥ 140 kPa after compaction treatment. The site is divided into a component stacking area, an assembly area, and a spraying area, with a distance of ≥ 5m between each area, and a rigid fence (height 1.2m) and warning signs are set;

[0071] For the crane occupancy area, the walking route width of the main crane (260t crawler crane) ≥ 8m, and the turning radius ≥ 12m; the bearing capacity of the foundation at the standing point of the tailing crane (80t truck crane) ≥ 200 kPa, and when necessary, a roadbed box (specification 2m × 6m × 0.2m) is laid.

[0072] For the material transportation channel: The existing road in the station is used, with a width ≥ 6m, widened to 8m at the turning point, a slope ≤ 5%, and the road surface is hardened with C30 concrete, with a thickness of 200mm;

[0073] The treatment and acceptance of each site specifically include:

[0074] Foundation compaction treatment, replacing the soft soil layer (the thickness of the crushed stone ≥ 500mm), and compacting it in layers with an 18t roller (each layer 300mm), with a compaction degree ≥ 95%;

[0075] Dig a drainage system, excavate a drainage ditch (cross-section 0.5m×0.5m) along the perimeter of the site with a slope of 0.5%, and connect it to the rainwater pipe network in the station area.

[0076] Acceptance criteria: Use a static load tester to detect the bearing capacity of the foundation, with the settlement ≤ 10mm / 2h; use a total station to review the deviation of the site axis ≤ 5mm.

[0077] Furthermore, in S2, when assembling the frame beam 2, it specifically includes the following steps:

[0078] Conduct on-site measurement of the center point of the beam to prevent the beam from being assembled off-center. When assembling, first complete the assembly of the bottom beam of the beam and then install the upper part of the steel truss beam;

[0079] When assembling the frame beam, assemble it on the ground according to the pre-arch value of the beam, and use a level to measure the pre-arch value (1 / 500 of the beam span); place a sleeper every 5 meters from the center of the sleeper position to both sides, and at the same time, the heights of the sleepers supported on both sides of the flange decrease successively;

[0080] When assembling the beam, follow the assembly procedure of first the lower chord and then the upper chord, and first the main materials and then the auxiliary materials. During assembly, strictly control the geometric dimensions, and assemble the steel truss beam walkway together with the steel truss beam;

[0081] The main bolts of the steel truss beam are inserted from the center to both ends, and the rest of the bolts are inserted from the inside of the steel truss beam to the outside of the steel truss beam.

[0082] Furthermore, in S4, the hoisting of each section of the frame column 1 specifically includes:

[0083] Hoisting of the bottom section of the frame column 11: The main hook is hung on the top node, use 2 Φ36.5mm steel wire ropes (6×37 strands, length 17m, breaking tensile force 856kN), the tailing hook is hung on the bottom node, and use 2 20t×10m nylon slings; after lifting 100mm off the ground, stand still for 10 minutes to check whether the crane outriggers settle (≤5mm) and whether the steel wire ropes are uniformly stressed (deviation ≤10%); after aligning the column foot of the bottom section of the frame column (11) with the anchor bolts, use a jack (20t) to adjust the verticality (deviation ≤H / 1500, H is the column height), and finally tighten the anchor bolts (torque value 500N·m);

[0084] Hoisting of the middle section of the frame column 12: The main crane slowly lifts, and the tailing crane cooperates with the rotation. The docking gap ≤ 3mm, insert a temporary positioning pin (diameter 42mm); tighten the bolts in the order of "from bottom to top, symmetrically tightened". After final tightening, remove the positioning pin and install a temporary diagonal brace (∠100×10 angle steel); use a theodolite (accuracy 2″) for detection, and readjust when the deviation exceeds 20mm;

[0085] Hoist the top-section frame column 13, calibrate the installation angle of the lightning rod 14 with a laser locator (verticality deviation ≤ 0.1°), and install the anti-loosening clamp after final tightening of the bolts; the base of the lightning rod 14 and the column top are welded with double-sided bevel welds (weld grade is first-class), and 100% UT inspection is carried out after welding;

[0086] The hoisting of the truss beam 2 specifically includes:

[0087] Set lifting lugs at 1 / 4 of the span from the beam end as lifting points. The lifting lug material is Q345B with a thickness of 30 mm, and the sling angle is 45° - 60°; adjustable lifting lugs are provided at both ends of the H-shaped steel balance beam (section H400×200×8×12, length 18 m), and a counterweight of 3 t is used to offset the wind load; measure the beam deflection after lifting 500 mm above the ground. If it exceeds L / 500, suspend hoisting and reinforce; after the beam end is in place, install a steel diagonal brace (Φ89×5 steel pipe) as a temporary support, and adjust the beam levelness with a hand-operated hoist (3 t); use a wireless torque wrench (range 200 - 1000 N·m) to tighten the bolts according to the design value, and upload the data to the management platform in real time; use a total station to check whether the axis deviation of the beam is ≤ 5 mm. If it exceeds the tolerance, loosen the bolts and reposition.

[0088] Further, in S3, the process parameters of the environmental protection spraying include: spraying pressure 0.4 - 0.6 MPa, the distance between the spray gun and the surface of the component is 300 - 500 mm; the dry film thickness of the coating is ≥ 150 μm (outdoor) or ≥ 125 μm (indoor); the waste gas treatment uses an activated carbon adsorption tower, and the VOC removal rate is ≥ 90%;

[0089] In S5, the Internet of Things torque monitoring system includes: a wireless torque sensor (embedded in the wrench, range 0 - 1000 N·m, sampling frequency 10 Hz), a LoRa gateway (transmission distance ≥ 1 km, power consumption ≤ 1 W), and a cloud management platform (supporting data storage, analysis, and report generation).

[0090] Further, the construction method also includes: a progress dynamic adjustment mechanism, safety risk control measures, and waste management measures, specifically including:

[0091] The progress dynamic adjustment mechanism simulates the construction progress based on the BIM + GIS platform, and updates the data of material arrival, mechanical occupancy, and personnel allocation daily; if the material delay is ≥ 3 days, start the backup supplier and adjust the hoisting sequence, and give priority to installing the truss sections that are not affected; if encountering bad weather, convert the high-altitude operation to ground assembly and activate the emergency material inventory;

[0092] Safety risk control measures adopt the LEC method for risk assessment. For level 4 risk operations, a "red ticket" must be issued by the project manager, and for level 3 risk operations, a safety officer must be on-site throughout the process. High-altitude workers are equipped with double-hook safety belts, vertical climbing self-locking devices, and anti-falling devices. The rope tensile strength of the self-locking device is ≥22 kN. Hard fences and audible and visual warning devices are set up in the hoisting area, and non-operating personnel are prohibited from entering within a radius of 30 m.

[0093] Waste management measures: Waste paint buckets and galvanized slag are stored separately in airtight containers and handed over to a hazardous waste treatment qualified unit for disposal. The recovery rate of wire rope and bolt packaging materials is ≥95%. Metal waste is crushed and used for subgrade filling after treatment. Construction wastewater is treated in a three-stage sedimentation tank and discharged with the pH value controlled within the range of 6 - 9.

[0094] Example 3, A construction method for a full-steel pipe space truss structure framework of a 1000 kV substation. Taking the new construction project of a 1000 kV substation in a certain city as an example, the site is located in a certain district of the city, adjacent to the ±800 kV converter station of the city on the west side. The straight-line distance from the site to the city in the southwest is about 5 km, and the straight-line distance to a certain district is about 25 km. The straight-line distance from the site to another district in the southeast is about 17.5 km. The site is about 290 m east of the S109 provincial road, with convenient transportation. It is about 41 km south of the international container terminal of the city, and the large-piece terminal can be reached through the S109 provincial road, with good large-piece transportation conditions.

[0095] In this embodiment, the framework columns GZ-1 and the framework beams GL-2 are the heaviest, so GZ-1 and GL-2 are selected as the calculation objects.

[0096] The main crane selects a 260t crawler crane, in tower crane working condition. For the selection of the boom length: The maximum lifting height H = 71 m, and the working radius is selected as 19 m. The main boom length is selected as 42 m, and the tower boom length is 36 m. The maximum lifting height obtained is 772 - 172 = 75 m, meeting the requirements.

[0097] As Figures 7 to 9 shown, for the main crane check: The hook weight is 3.1 t, and the total weight is 28.8 + 3.1 = 31.9 t, 31.9×1.2×1.3 = 49.76 t. According to the tower crane working condition table of the 260t crawler crane, with a working radius of 19 m, the allowable lifting weight is 59.1 t. It can be obtained that the load is 49.76 / 59.1 = 84%, and the working condition is satisfied.

[0098] For the tailing crane check; M1 = 14.47 t, M2 = 8.42 t, M3 = 6.01 t

[0099] According to the force balance, it can be obtained that:

[0100] T auxiliary = (22·G1 + 12·G2 + 4·G3) / 27 = (22·M1 + 12·M2 + 4·M3)g / 27

[0101] =(22×14.47 + 12×8.42 + 4×6.01)×10 / 27 = 164.23 kN

[0102] The weight of the hook is 1 t, and the total weight is 17.5 t. 17.5×1.2×1.3 = 27.3. According to the lifting performance table of an 80 t truck crane, the boom length is 16.8 m, the working radius is 8 m, and the allowable lifting weight is 40 t. It can be obtained that the load is 27.3 / 40 = 68%, and the working condition is satisfied.

[0103] Wire rope check

[0104] During the lifting process

[0105]

[0106] That is, 2 slings of 20 t×10 m meet the requirements.

[0107] During the hoisting operation:

[0108]

[0109] The total breaking force of the wire rope P = 856.0 kN, the conversion coefficient of the breaking force α = 0.82; the safety factor of the wire rope K = 7; the allowable stress of the wire rope [S] ≤ αP / K = 0.82×856.0 / 7 = 100.27 kN; the tensile force borne by the wire rope S = 76.27 kN is less than the allowable stress of 100.27 kN, and the bearing capacity check of the wire rope passes.

[0110] Through the modular design of the framework, intelligent hoisting technology and integrated safety control system, efficient, safe and green UHV construction is realized. The coordinated operation of a 260 t crawler crane and an 80 t truck crane, combined with Internet of Things monitoring and BIM dynamic simulation, significantly improves the construction accuracy and efficiency. This technology is applicable to UHV project construction under complex working conditions and has wide popularization value.

[0111] For those skilled in the art, it is obvious that the present invention is not limited to the details of the above exemplary embodiments, and can be implemented in other specific forms without departing from the spirit or basic characteristics of the present invention. Therefore, from any point of view, the embodiments should be regarded as exemplary and non-restrictive. The scope of the present invention is defined by the appended claims rather than the above description. Therefore, all changes falling within the meaning and scope of the equivalent elements of the claims are intended to be included in the present invention. Any reference signs in the claims should not be regarded as limiting the claimed rights.

[0112] In addition, it should be understood that although this specification is described according to embodiments, not every embodiment only contains an independent technical solution. This narrative way of the specification is only for clarity. Those skilled in the art should regard the specification as a whole, and the technical solutions in each embodiment can also be appropriately combined to form other embodiments that can be understood by those skilled in the art.

Claims

1. A fully steel pipe space truss structure framework for a 1000 kV substation, comprising framework columns (1) and framework beams (2), characterized in that: The frame column (1) is vertically and fixedly connected to the foundation, and the frame beam (2) is horizontally and fixedly connected between two frame columns (1). The frame column (1) includes a bottom frame column (11), a middle frame column (12), and a top frame column (13) arranged in sequence from bottom to top. Each butt joint of the frame column (1) is connected by a flange and bolts. The two ends of the frame beam (2) are fixedly connected to the column body of the middle frame column (12) by bolts. A lightning rod (14) is connected to the top end of the top frame column (13). The connection node between the frame column (1) and the frame beam (2) is an embedded rigid connection, and stiffening rib plates are arranged at the node. Double-sided groove welding is used for welding.

2. The all-steel pipe space truss structure framework of a 1000 kV substation according to claim 1, characterized in that: The frame column (1) is a full-steel pipe space truss structure, and the frame beam (2) is a lattice beam with a rectangular cross-section. The flange connection between the frame column (1) and the frame beam (2) is reinforced with symmetric flat steel plates.

3. The all-steel pipe space truss structure framework of a 1000 kV substation according to claim 1, characterized in that: Ladders and rest platforms are arranged at the interfaces of each section of the frame column (1). Cage guards are fixedly connected to both sides of the ladders by bolts, and platform gratings are fixedly laid on the rest platforms by bolts.

4. A fully steel pipe space truss structure framework for a 1000 kV substation according to claim 1, characterized in that: Anchor bolts are embedded in the foundation. Double nuts are screwed onto the anchor bolts, and washers are sleeved on the anchor bolts.

5. A construction method for a fully steel pipe space truss structure framework of a 1000 kV substation, characterized in that: A full-steel pipe space truss structure frame for a 1000 kV substation according to any one of claims 1 to 4, characterized in that the construction method includes the following steps: S1. Construction site planning: The construction site is divided into areas, which are respectively divided into: a ground assembly area, a crane occupancy area, and a material transportation passage. Each of the divided sites is processed and accepted. S2. Sectional assembly: The ground assembly of the bottom frame column (11), the middle frame column (12), and the top frame column (13) of the frame column (1) and the ground assembly of the frame beam (2) are respectively carried out. Each section of the frame column (1) is composed of several joint columns welded by steel pipes. Sleepers are laid on the ground as pads. For the ground assembly of each section of the frame column (1), the joint columns are placed on the pads. A laser alignment instrument is used to calibrate the flanges of adjacent joint columns to align the flange holes of the adjacent joint columns. Bolts are passed through the aligned flange holes, and a hydraulic torque wrench is used to tighten symmetrically three times. Ladders and rest platforms are installed on each assembled section of the frame column. For the ground assembly of the frame beam (2), pre-camber control is carried out. The pre-camber is set at 1 / 500 of the span. A hydraulic jack is used for lifting and adjustment, and a total station is used for real-time monitoring. The main material bolts are inserted from the center to both ends, and the auxiliary material bolts are inserted from the inside to the outside, with a thread exposure length of 2 - 3 threads. S3. Environmentally friendly spraying: After the assembly of each section of the frame column (1) and the frame beam (2), sea gray 919 paint is sprayed on the ground. Stratified spraying is adopted during spraying, and anti-pollution colored strip cloth is laid in the spraying area. S4, hoisting process: during the hoisting construction, firstly, each section of the frame column (1) is hoisted in groups by using a main hoist and a tail crane. The main hoist is a 260t crawler crane, and the tail crane is an 80t truck crane. After the installation of the bottom section frame column (11) is completed, all the anchor bolts are tightened in time. After the anchor bolts are tightened, a temporary grounding wire is installed in time. After the installation of the bottom section frame column (11) above the foundation is completed, the geometric dimensions of the frame column are re-measured with a total station. Thereafter, the geometric dimensions of each section of the frame column are re-measured after the installation is completed. The column foot is adjusted with a jack or a track hoist, and the upper part of the frame column is corrected with a rope. After the hoisting of the frame column (1) is completed, the frame beam (2) is four-point tied + single-machine hoisted, and the frame beam (2) is hoisted by the four-point tied method, and the frame beam (2) is hoisted to the middle section frame column (12) area and fixed by bolts; S5. Bolt control: The IoT torque monitoring system is used to upload bolt tightening data to the management platform in real time. The sensor collects torque value, bolt number and operator information. The collected information data is encrypted by the gateway and uploaded to the cloud. The platform automatically compares the design value, and triggers an audible and visual alarm and SMS notification when the deviation is ≥10%.

6. The construction method according to claim 5, characterized in that: In S1, for the ground assembly area, the GIS area is used as the ground assembly site for the frame, and the site is divided into component stacking area, assembly area and spraying area. The distance between each area is ≥5m, and hard fences and warning signs are set; For the crane occupation area, the main crane travel route width is ≥8m, and the turning radius is ≥12m; The bearing capacity of the foundation of the tail crane station is ≥200kPa; For material transportation channels: use existing roads within the station, with a width of ≥6m and a slope of ≤5%, and the road surface is hardened with C30 concrete; The processing and acceptance of each site specifically includes: The foundation is compacted and the soft soil layer is replaced and compacted layer by layer using an 18t roller with a compaction degree of ≥95%; Dig a drainage system, dig drainage ditches along the perimeter of the site, and connect to the station area rainwater pipe network.

7. The construction method according to claim 5, characterized in that: In S2, when assembling the frame beam (2), the following steps are specifically included: The center point of the beam is measured on site to prevent the beam from being assembled off-center. When assembling, the bottom beam of the beam is assembled first and then the upper steel truss is installed; When assembling the frame beam, assemble it on the ground according to the pre-arch value of the beam, and measure the pre-arch value with a level; arrange a rail every 5 meters from the center of the rail position to both sides, and at the same time, the height of each rail supported on both sides of the flange decreases in sequence; When assembling the beams, the assembly procedure is to first assemble the lower chord and then the upper chord, and first the main material and then the auxiliary material. The geometric dimensions are strictly controlled during assembly, and the steel truss walkway is assembled together with the steel truss. The main bolts of the steel truss are passed from the center to both ends, and the remaining bolts are passed from the inside of the steel truss to the outside of the steel truss.

8. The construction method according to claim 5, characterized in that: In S4, the hoisting of each section of the frame column (1) specifically includes: The bottom frame column (11) is hoisted by hanging the main hook on the top node using a steel wire rope, and hanging the tail hook on the bottom node using a nylon sling; after lifting off the ground, let it stand to check whether the crane legs have settled and whether the steel wire rope is evenly stressed; after the column foot of the bottom frame column (11) is aligned with the anchor bolt, use a jack to adjust the verticality, and finally tighten the anchor bolt; Hoisting of the middle-section frame column (12): The main crane slowly lifts, and the tailing crane cooperates in rotation. The docking gap ≤ 3 mm. Insert temporary positioning pins. Tighten the bolts in the order of "from bottom to top, symmetrically applying torque". After final torque application, remove the positioning pins and install temporary diagonal braces. Use a theodolite for detection. If the deviation exceeds 20 mm, readjust. Hoisting of the top-section frame column (13), calibrate the installation angle of the lightning rod (14) with a laser locator. Install the anti-loosening clamp after final torque application of the bolts. The base of the lightning rod (14) and the column top are welded with double-sided bevel grooves, and 100% UT inspection is carried out after welding. The hoisting of the frame beam (2) specifically includes: Set lifting lugs at 1 / 4 of the span from the beam end as lifting points. Adjustable lifting lugs are provided at both ends of the H-shaped steel balance beam, and counterweights are used to offset the wind load. Measure the beam deflection after lifting off the ground. If it exceeds L / 500, suspend hoisting and reinforce. After the beam end is in place, install a steel diagonal brace as a temporary support, and use a hand winch to adjust the beam levelness. Use a wireless torque wrench to tighten the bolts according to the design value, and upload the data to the management platform in real time. Use a total station to check whether the axis deviation of the beam is ≤ 5 mm. If it exceeds the tolerance, loosen the bolts and reposition.

9. The construction method according to claim 5, wherein: In S3, the process parameters of the environmental protection spraying include: spraying pressure 0.4 - 0.6 MPa, the distance between the spray gun and the surface of the component 300 - 500 mm; the dry film thickness of the coating ≥ 150 μm or ≥ 125 μm; the waste gas treatment uses an activated carbon adsorption tower, and the VOC removal rate ≥ 90%. In S5, the Internet of Things torque monitoring system includes: wireless torque sensors, LoRa gateways, and cloud management platforms.

10. The construction method according to claim 5, characterized in that: The construction method further includes: a progress dynamic adjustment mechanism, safety risk control measures, and waste management measures, specifically including: The progress dynamic adjustment mechanism simulates the construction progress based on the BIM + GIS platform, and updates the data of material arrival, mechanical occupancy, and personnel allocation daily; if the material delay ≥ 3 days, activate the backup supplier and adjust the hoisting sequence, and give priority to installing the unaffected frame sections; if encountering bad weather, convert the high-altitude operation to ground assembly and activate the emergency material inventory. The safety risk control measures use the LEC method for risk assessment. For level 4 risk operations, the project manager needs to issue a "red ticket", and for level 3 risk operations, the safety officer should be on site throughout the process; high-altitude operators are equipped with double-hook safety belts, vertical climbing self-locking devices, and fall arresters, and the rope tensile strength of the self-locking device ≥ 22 kN; hard fences and sound and light warning devices are set in the hoisting area, and non-operating personnel are prohibited from entering within a radius of 30 m. For the waste management measures, the waste paint buckets and galvanized slag are stored separately in sealed containers and handed over to a hazardous waste treatment qualified unit for disposal; the recovery rate of wire ropes and bolt packaging materials ≥ 95%, and the metal waste is crushed and used for subgrade filling; the construction wastewater is treated by a three-stage sedimentation tank, and the pH value is controlled within the range of 6 - 9 for discharge.

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