Firewall of extra-high voltage converter station and construction process of firewall

Abstract

The invention discloses a firewall of an extra-high voltage converter station and a construction process thereof, the firewall comprises a reinforced concrete shear wall, and the construction process comprises construction section division, scaffold installation, template installation, concrete pouring, firewall maintenance and post-cast strip construction. On the basis of structural mechanics analysis and BIM simulation, the firewall is divided into construction sections, and the transportation capacity of the tower crane is matched; the combined steel frame-wood formwork, the keel and the split bolts are adopted to construct the form of the formwork, and the overall rigidity and the formwork mounting and dismounting efficiency are both improved; through full-chain innovation of the construction technology, collaborative optimization of efficiency, cost, environmental protection and safety is achieved on the premise that the safety of the firewall structure is guaranteed, and reliable technical support is provided for construction of the extra-high-voltage direct-current converter station.

Description

Technical Field

[0001] The present invention relates to a firewall, specifically a firewall for a UHV converter station and its construction technology, belonging to the technical field of electric power facility engineering. Background Art

[0002] The UHV DC (HVDC) converter station is the core facility for realizing cross-regional power grid interconnection and long-distance transmission of clean energy. Its safety and reliability directly affect the stable operation of the power grid. Core equipment in the converter station (such as converter transformers, valve hall equipment, etc.) is prone to fire risks under high-voltage and large-current conditions. Therefore, as a key protection structure, the firewall must possess the following core functions: Physical isolation: Prevent the spread of fire and protect adjacent equipment and buildings; Structural load-bearing: Resist equipment explosion shocks, seismic loads, and wind loads; Durability performance: Long-term tolerance to extreme temperatures, humidity, and chemical corrosion; Construction efficiency: Adapt to the requirements of large-scale projects with tight construction periods and reduce on-site operation risks. However, as the voltage level increases to ±800 kV and above, a series of technical bottlenecks have gradually emerged in the traditional firewall construction technology, and it is urgent to achieve breakthroughs through process innovation.

[0003] In the prior art, such as a substation sound insulation device and the overall structure and construction technology of a firewall disclosed in publication number CN113738165A, which includes a plate body and a fireproof board fixedly connected inside the plate body, and an inner wall of the plate body is fixedly connected with a ring matching the inner wall of the plate body; the construction technology includes: The composite material lightweight fireproof wall module adopts a plug-in structure, measures the specific dimensions of the construction area, and issues a specific construction zoning layout diagram according to the actual on-site dimensions. The composite material lightweight fireproof wall with strong practicability is adopted. The composite material lightweight fireproof wall has the advantages of modular assembly, light structural weight, very good fireproof performance, safety and reliability, etc., and can also be customized according to the fireproof time requirements of each area of the substation, and the longest fire resistance time can reach 4 hours for the traditional converter station firewall. However, for the existing firewall, the structural stability is insufficient, the firewall thickness is small (usually 200 - 300 mm), the protection ability for high-voltage equipment is limited, and the seismic performance is poor. Although the modular plug-in structure can improve the construction efficiency, it is difficult to control the verticality of large-height walls (such as above 20 m), and cast-in-place concrete is required at the joints, and there is still a risk of shrinkage cracks; the prefabricated parts are heavy (single piece > 5 tons), relying on heavy lifting equipment, and the cost increases by 25%; the applicability is limited, it is difficult to adapt to the complex pipeline embedding requirements of the converter station, and accidents such as collapse and high-altitude fall are prone to occur during the scaffolding erection and formwork installation processes. Moreover, the existing technology targets the wall structure of the firewall, and there is no good improvement in the specific construction technology. In view of the above problems, the industry has proposed various improvement schemes, but there are still significant deficiencies. Based on this, this application proposes a firewall for a UHV converter station and its construction technology. Summary of the Invention

[0004] The object of the present invention is to provide a firewall for a UHV converter station and its construction technology to solve at least one of the above technical problems.

[0005] The present invention realizes the above object through the following technical solutions: A firewall for a UHV converter station includes a reinforced concrete shear wall. A post-cast strip is arranged in the wall body of the reinforced concrete shear wall. A cantilever eaves and a gutter are cast at the top of the reinforced concrete shear wall, and the gutter is located above the cantilever eaves.

[0006] When casting the wall body of the reinforced concrete shear wall, a combined steel frame-wood formwork assembly is built. The combined steel frame-wood formwork assembly includes a composite wood formwork, square steel inner keels, and channel steel outer keels. The formwork and keels of the combined steel frame-wood formwork assembly are connected and fixed by tie bolts. The post-cast strip is arranged in the middle of the wall body, and a galvanized corrugated steel mesh is used to isolate the post-cast strip from the shear wall bodies on both sides during the pouring process.

[0007] As a further solution of the present invention: The reinforced concrete shear wall includes a low-end firewall and a high-end firewall;

[0008] The width of the post-cast strip is 800 - 1000 mm. When pouring the post-cast strip, an independent formwork is built. The thickness of the galvanized corrugated steel mesh used for the formwork on both sides is 0.5 - 0.7 mm, and the mesh size is 3 - 5 mm; The strength grade of the compensated shrinkage concrete is C35, and the restricted expansion rate ≥ 0.025%. The pouring time of the post-cast strip is 45 - 50 days after the main structure concrete of the reinforced concrete shear walls on both sides is cured;

[0009] When casting the wall body of the reinforced concrete shear wall, a PE cotton strip is embedded at the formwork joint of the combined steel frame-wood formwork assembly; The square steel inner keels are arranged vertically and fixed to the formwork by countersunk head self-tapping screws. The spacing of the square steel inner keels is 230 - 270 mm, and the screw spacing is 150 - 200 mm; The channel steel outer keels are arranged horizontally and connected to the scaffolding by short steel pipes and right-angle fasteners. The spacing of the channel steel outer keels is 350 - 450 mm.

[0010] The tie bolts adopt M20 high-strength bolts. The horizontal spacing is 350 - 450 mm, and the vertical spacing is 2400 - 2600 mm. Double nuts are screwed at both ends of the tie bolts for locking, and a PVC sleeve is sleeved on the bolt body at the end of the tie bolt. It should be noted that the material of the tie bolt is HPB300 grade steel, the total length is 900 mm, the PVC sleeve is a high-quality water supply sleeve, the inner diameter is 22 mm, and the gap with the formwork hole ≤ 1 mm; The design value of the bolt tensile strength is 47.9 kN, and the checking formula is:

[0011] N = 0.95 × m × n × S 承 ≤ N tb

[0012] Among them, S 承 is the design value of the lateral pressure;

[0013] A drip line is set at the end of the cantilever eaves, and the drip line is 45-55mm away from the edge of the wall; and the cantilever eaves support is a steel pipe diagonal brace, the bottom is anchored at the tension bolts, and the cantilever 3 length is 1.9-2m;

[0014] Downpipe openings are pre-buried at the bottom of the gutter, with a spacing of 4-6m between the openings, a slope of ≥2% at the bottom of the gutter, a diameter of 100mm for the downpipe openings, and a height of 2.575-3.108m for the gutter 4.

[0015] A construction process for a firewall of an ultra-high voltage converter station includes a firewall. The construction process includes the following steps:

[0016] S1. Construction section division: According to the height of the firewall, the location of the variable cross-section of the structure and the construction load transfer path, the principle of "vertical segmentation and horizontal continuity" is adopted to reduce the impact of construction joints on integrity. The low-end firewall is divided into 9 sections and the high-end firewall is divided into 13 sections. The height of the first floor is 1.6m, the middle layer is 2.5m, and the top layer is 1.15m to 1.35m. The low-end firewall adopts the "two-shift" mode, and the construction period of each section is 5 days. The high-end firewall is inserted into the construction of the low-end to the 4th section, and the tower crane is used to transport materials vertically. The construction period of each section is extended to 6 days to ensure that there is no conflict in the connection of the process. The horizontal construction joint is set at the top of each section.

[0017] S2. Scaffolding installation. The frame is set up with formwork racks and construction work racks. Steel pipe fastener scaffolding is used. The plane is set up along the perimeter of the firewall. The high-end firewall back wall valve hall side uses double rows of double poles, with a height of 31m; the back wall converter side uses three rows of double poles, with a height of 32m; the partition wall uses double rows of single poles, with a height of 13m; the low-end firewall back wall valve hall side uses double rows of single poles, with a height of 21m; the back wall converter side uses three rows of single poles, with a height of 22m; the partition wall uses double rows of single poles, with a height of 13m.

[0018] S3, template installation, axis and elevation control, use total station to check axis, measure from benchmark control network; use level to measure elevation, set elevation control point at the top of each section, template assembly is carried out in the order of panel assembly, inner keel fixation, outer keel installation and inner corner reinforcement, and the assembled template is connected and fixed by tension bolts;

[0019] S4, concrete pouring, using C30 fiber concrete, advancing from 2-axis to 8-axis along the length of the firewall, layer thickness 450-500mm, slope gradient 1:6-1:8, vibrator inserted 50-55mm into the lower concrete, and re-vibrated twice in the top 450-500mm range;

[0020] S5. Firewall maintenance: spray cement-based penetrating crystalline protective liquid after demoulding, cover with plastic film for moisture maintenance for ≥14 days, humidity ≥90%;

[0021] S6. During the construction of post-cast strips, galvanized corrugated steel meshes are installed on both sides of the post-cast strips and fixed to the main structure by welding with steel bars. A temporary wooden formwork is set on the outside of the steel meshes to prevent deformation caused by the side pressure of the concrete. After pouring, the strips are covered with plastic film + cotton felt for insulation and maintenance for 28 days. Water them ≥4 times a day in the first 7 days.

[0022] As a further solution of the present invention: in S2, the scaffolding parameters are:

[0023] The vertical distance of the poles is 1.5m, the horizontal distance is 0.9m, and the step distance is 1.8m;

[0024] The wall ties are arranged in “two steps and three spans”, with a horizontal spacing of 3m and a vertical spacing of 2.5m;

[0025] The scissor brace covers every 4 spans and is ≥6m, with an inclination of 45°-60° to the ground;

[0026] The scaffolding boards are made of 50mm thick bamboo planks, and the ends are fixed with Φ3.2mm galvanized iron wire.

[0027] As a further solution of the present invention: in S3, the template assembly specifically includes:

[0028] For panel assembly: pre-assemble 3 pieces of 2440mm×1220mm composite wood formwork on the ground to form a 3660mm×2440mm large formwork, seal the board seams with double-sided tape, and fill the nail holes with automotive putty;

[0029] For fixing the inner keel: 40×80×4mm square steel is arranged vertically for 250mm, connected to the template by Φ5mm countersunk self-tapping screws for 200mm, and the screws are sunk into the board surface ≤1mm;

[0030] For external keel installation: channel steel is arranged horizontally at 400mm, connected to double-row scaffolding poles through Φ48×3.5mm short steel pipes and right-angle fasteners, and the node spacing is ≤500mm;

[0031] For internal corner reinforcement: set up L-shaped wooden corner formwork at the intersection of vertical and horizontal walls, and weld 80×40×4mm square steel diagonal braces on the back with a spacing of ≤600mm;

[0032] When connecting and fixing the tie bolts, drill the bolt holes in advance, insert Φ20mm HPB300 bolts and PVC sleeves, and the two ends of the sleeves protrude from the formwork surface by ≤5mm;

[0033] Installation of dividing strips: Embed 100mm×10mm flat iron at the formwork joints. After removal, a groove is formed, and gray epoxy resin sealant is applied in the groove.

[0034] As a further solution of the present invention: Before assembling the panel, apply salad oil release agent, spray evenly without flowing; the initial tightening torque is 85-90N·m, and after correcting the verticality, re-tighten to 100-110N·m; the dividing strip is made of 10mm thick flat iron, and after removal, a 100×10mm decorative groove is formed.

[0035] As a further solution of the present invention: In S4, the pouring of C30 fiber concrete specifically includes:

[0036] Use a concrete pump truck with a 46m boom length, the pump pipe diameter is 125mm, and the outlet pressure ≥12MPa; first pour 50mm thick cement mortar with the same mix ratio at the bottom of each section; use a ZN50 inserted vibrator, the moving spacing ≤400mm, and the distance from the formwork ≤150mm; the vibration time is 20-30 seconds per point, based on the concrete surface showing slurry and no bubbles, over-vibration or missed vibration is strictly prohibited; in the top 500mm range, re-vibrate twice before initial setting to eliminate the bleeding channels; the concrete pouring temperature is controlled at 5-30°C, cover with wet gunny bags in summer to cool down, and use heated mixing water in winter; immediately cover with plastic film + geotextile after final setting to prevent surface water evaporation, and external loads are prohibited during the curing period;

[0037] The mix ratio of C30 fiber concrete is:

[0038] Cement: P.O42.5 ordinary Portland cement, dosage 380-420kg / m 3 ;

[0039] Aggregate: Medium sand with fineness modulus 2.3-3.0, mud content ≤1%; crushed stone with particle size 5-21.5mm, mud content ≤0.5%;

[0040] Admixture: UF500 anti-cracking fiber dosage 0.9kg / m 3 , water reducing agent dosage 1.2% - 1.5%;

[0041] Slump: 160-180mm, initial setting time ≥4 hours.

[0042] As a further solution of the present invention: In S5, the curing of the firewall specifically includes:

[0043] Form removal time: The side form is removed after the concrete strength ≥1.2MPa, and the bottom form is removed after the strength ≥100% of the design value;

[0044] Maintenance method: Spray cement-based penetrating crystalline protective liquid with a dosage of ≥ 1.5 kg / m 2 , and the interval time is 4 - 6 hours;

[0045] Environmental control: During maintenance, the humidity ≥ 90%, the temperature is 5°C - 35°C, and in case of rain or snow, cover with a rainproof cloth;

[0046] Within 3 days after form removal, set up a protective railing 1 m away from the wall to prevent mechanical collision;

[0047] Plugging of the tie bolts: Use 1:2.5 dry-hard mortar to fill in three times at intervals of 24 hours, and the surface is troweled smooth and flush with the wall.

[0048] As a further solution of the present invention: In S6, the construction of the post-cast strip specifically includes:

[0049] Compensated concrete pouring:

[0050] Mix ratio: C35 concrete is admixed with HEA expansion agent, and the restricted expansion rate ≥ 0.025%;

[0051] Pouring time: 45 days after the completion of the main structure construction;

[0052] Vibration requirements: Use a combined vibration of an attached vibrator + an inserted vibrator to ensure the density behind the steel mesh.

[0053] As a further solution of the present invention: The construction process also includes safety control of the construction area, quality acceptance standards, intelligent monitoring and BIM collaborative monitoring, and construction environmental protection measures; specifically:

[0054] a. Safety control of the construction area includes:

[0055] Risk classification: Evaluated by the LEC method, the risk value of scaffold collapse D = 126, and the risk value of object strike D = 54;

[0056] Emergency treatment: Set up a warning area, equipped with anti-falling devices, safety nets and fire extinguishers, and the emergency plan covers scenarios of collapse, fire and high-altitude fall;

[0057] Personnel qualifications: Scaffolders, welders, and crane operators hold special operation certificates, and the signature rate of technical disclosure is 100%;

[0058] b. Quality acceptance standards include:

[0059] Formwork installation: The axial displacement ≤ 4 mm, the cross-sectional dimension deviation is ± 4 mm, and the surface flatness ≤ 3 mm;

[0060] Reinforcement works: The main reinforcement spacing is ± 10 mm, the deviation of the protective layer thickness is ± 3 mm, and the torque value of the straight thread connection ≥ 260 N·m;

[0061] Concrete strength: The compressive strength at 28 days ≥ 34.5 MPa, and the carbonation depth ≤ 2.0 mm.

[0062] c. Intelligent monitoring and BIM collaborative monitoring include:

[0063] Using a total station to monitor the deviation of the formwork axis and elevation error in real time;

[0064] The BIM model simulates the construction process, optimizes the material transportation path and tower crane positioning;

[0065] Using a drone to inspect the perpendicularity of the wall, and uploading the data to the cloud analysis platform;

[0066] d. Construction environmental protection measures include:

[0067] The recovery rate of concrete waste ≥ 85%, and the sewage is discharged after being treated to meet the standards in the sedimentation tank;

[0068] The construction noise ≤ 70 dB during the day and ≤ 55 dB at night, and the dust PM10 concentration ≤ 0.5 mg / m 3 ;

[0069] The waste formwork and steel bars are classified and recycled, and the comprehensive utilization rate ≥ 90%.

[0070] The beneficial effects of the present invention are:

[0071] 1) Based on structural mechanics analysis and BIM simulation, the present invention divides the firewall into 9 - 13 construction segments according to the height, with each segment having a height of 1.15 - 2.5 m, matching the tower crane transportation capacity; the construction efficiency is greatly improved compared with the traditional equal division method;

[0072] 2) The present invention uses composite wood formwork, keels and tie bolts to construct the formwork shape, and both the overall stiffness and the formwork installation and removal efficiency are improved;

[0073] 3) The present invention uses fair - faced concrete, with polypropylene fibers added to C30 concrete, and the crack - resistance performance is improved by 40%; adopting the "ramp - layered + secondary vibration" process, the vibration time within the top 500 mm range is extended to 45 seconds, and the bubble elimination rate > 95%; spraying a cement - based penetrating crystalline protective liquid to form a slightly expanded waterproof layer, replacing traditional plastering, and shortening the construction period by 15 days;

[0074] 4) Through the full - chain innovation of the construction process, on the premise of ensuring the structural safety of the firewall, the present invention realizes the coordinated optimization of efficiency, cost, environmental protection and safety. Its comprehensive performance indicators far exceed the industry standards, providing reliable technical support for the construction of UHV DC converter stations and having broad industrial application prospects. Description of the Drawings

[0075] Figure 1Schematic diagram of the three-dimensional structure of the firewall of the present invention;

[0076] Figure 2 For the present invention Figure 1 Schematic diagram of the structure at location A in the present invention;

[0077] Figure 3 Schematic diagram of the construction process of the firewall of the present invention;

[0078] Figure 4 Schematic diagram of the plan layout of the firewall of the present invention;

[0079] Figure 5 Schematic diagram of the specification for calculating the lateral pressure of the present invention;

[0080] Figure 6 Schematic diagram of the panel type of the present invention;

[0081] Figure 7 Schematic diagram of the force on the panel of the present invention;

[0082] Figure 8 Schematic diagram of the bending moment of the panel of the present invention;

[0083] Figure 9 Schematic diagram of the deformation of the panel of the present invention;

[0084] Figure 10 Schematic diagram of the type of internal keel of the present invention;

[0085] Figure 11 Schematic diagram of the force on the internal keel of the present invention;

[0086] Figure 12 Schematic diagram of the bending moment of the internal keel of the present invention;

[0087] Figure 13 Schematic diagram of the shear force of the internal keel of the present invention;

[0088] Figure 14 Schematic diagram of the deformation of the internal keel of the present invention;

[0089] Figure 15 Schematic diagram of the type of external keel of the present invention;

[0090] Figure 16 Schematic diagram of the force on the external keel of the present invention;

[0091] Figure 17 Schematic diagram of the bending moment of the main beam of the external keel of the present invention;

[0092] Figure 18 Schematic diagram of the deformation of the main beam of the external keel of the present invention;

[0093] Figure 19 Schematic diagram of the type of tie bolts of the present invention;

[0094] In the figure: 1. Reinforced concrete shear wall; 2. Post-cast strip; 3. Cantilever eaves; 4. Gutter. Specific implementation manner

[0095] The following will clearly and completely describe the technical solutions in the embodiments of the present invention with reference to 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. All other embodiments obtained by those of ordinary skill in the art based on the embodiments of the present invention without creative efforts shall fall within the protection scope of the present invention.

[0096] Embodiment 1, as Figures 1 to 2 shown, a firewall of a UHV converter station includes a reinforced concrete shear wall 1. A post-cast strip 2 is arranged in the middle of the wall body of the reinforced concrete shear wall 1. A cantilever eaves 3 and a gutter 4 are cast at the top of the reinforced concrete shear wall 1, and the gutter 4 is located above the cantilever eaves 3;

[0097] When casting the wall body of the reinforced concrete shear wall 1, a combined steel frame-wood formwork assembly is built. The combined steel frame-wood formwork assembly includes 18-mm-thick composite wood formwork, 40×80×4-mm square steel inner keels, and channel steel outer keels. The formwork and keels of the combined steel frame-wood formwork assembly are connected and fixed by tie bolts. The post-cast strip 2 is arranged in the middle of the wall body, and a galvanized corrugated steel mesh is used to isolate between the post-cast strip 2 and the shear wall bodies on both sides.

[0098] The reinforced concrete shear wall 1 includes a low-end firewall and a high-end firewall. The thickness of the low-end firewall is 300 mm, the height is 18.725 m, and the plane axis dimensions are 76.5 m×18.5 m; the thickness of the high-end firewall is 400 mm, and it is locally thickened to 500 mm near the valve hall side. The height is 29.058 m, and the plane axis dimensions are 86.2 m×20.5 m;

[0099] The width of the post-cast strip 2 is 800 - 1000 mm. When casting the post-cast strip 2, an independent formwork is built. The thickness of the galvanized corrugated steel mesh used for the formwork on both sides is 0.5 - 0.7 mm, and the mesh size is 3 - 5 mm; the strength grade of the compensated shrinkage concrete is C35, and the restricted expansion rate is ≥0.025%. The pouring time of the post-cast strip 2 is 45 - 50 days after the main structure concrete of the reinforced concrete shear walls 1 on both sides is cured;

[0100] 2mm thick PE rubber cotton strips are embedded in the formwork joints of the combined steel frame-wood formwork assembly built when pouring the reinforced concrete shear wall 1; the inner square steel keel is arranged vertically and fixed to the formwork by countersunk self-tapping screws, the spacing between the inner square steel keels is 230-270mm, and the spacing between the screws is 150-200mm; the outer channel steel keel is arranged horizontally and connected to the scaffolding by short steel pipes and right-angle fasteners, the spacing between the outer channel steel keels is 350-450mm, ensuring the formation of an overall stable system.

[0101] The tension bolts are M20 high-strength bolts, with a horizontal spacing of 350-450mm and a vertical spacing of 2400-2600mm. The two ends of the tension bolts are threaded and locked with double nuts, and the bolt ends are sleeved with PVC sleeves. It should be noted that the tension bolts are made of HPB300 grade steel with a total length of 900mm. The PVC sleeve is a high-quality water supply sleeve with an inner diameter of 22mm and a clearance of ≤1mm from the template hole.

[0102] The design value of the bolt tensile strength is 47.9kN, and the calculation formula is:

[0103] N=0.95×m×n×S 承 ≤N t b

[0104] Among them, S 承 is the design value of the lateral pressure;

[0105] A 20×20mm drip line is set at the end of the eaves 3, and the drip line is 45-55mm away from the edge of the wall; and the eaves 3 are supported by Φ48×3.5mm steel pipe diagonal braces, the bottom of which is anchored at the tension bolts, and the length of the cantilever 3 is 1.9-2m;

[0106] Downpipe openings are pre-buried at the bottom of gutter 4, the distance between the openings is 4-6m, the slope of the bottom of gutter 4 is ≥2%, the diameter of the downpipe openings is 100mm, and the height of gutter 4 is 2.575-3.108m.

[0107] Embodiment 2, as Figure 3 As shown, a construction process of a firewall of a UHV converter station includes a firewall, and the construction process includes the following steps:

[0108] S1. Construction section division: According to the height of the firewall, the location of the variable cross-section of the structure and the transmission path of the construction load, the principle of "vertical segmentation and horizontal continuity" is adopted to reduce the impact of the construction joint on the integrity. The low-end firewall is divided into 9 sections and the high-end firewall is divided into 13 sections. The height of the first floor is 1.6m, the middle layer is 2.5m, and the top layer is 1.15m to 1.35m. The low-end firewall adopts the "two-shift" mode, and the construction period of each section is 5 days. The high-end firewall is inserted into the construction of the low-end to the 4th section. The tower crane (80 type) is used to transport materials vertically. The construction period of each section is extended to 6 days to ensure that there is no conflict in the connection of the processes. The horizontal construction joint is set at the top of each section, 50mm away from the upper mouth of the template, and the roughening treatment is adopted (exposed aggregate ≥50%). The interface agent (cement: sand: glue = 1:1:0.5) is applied before pouring.

[0109] S2. Scaffolding installation. The frame is set up with formwork racks and construction work racks. Steel pipe fastener scaffolding is used. The plane is set up along the perimeter of the firewall. The high-end firewall back wall valve hall side uses double rows of double poles, with a height of 31m; the back wall converter side uses three rows of double poles, with a height of 32m; the partition wall uses double rows of single poles, with a height of 13m; the low-end firewall back wall valve hall side uses double rows of single poles, with a height of 21m; the back wall converter side uses three rows of single poles, with a height of 22m; the partition wall uses double rows of single poles, with a height of 13m.

[0110] S3, template installation, axis and elevation control, use total station (accuracy ±5″) to check the axis, measure from the benchmark control network, allowable deviation ≤3mm; level (DS3 level) to measure elevation, set elevation control point at the top of each section (±0.00m corresponds to absolute elevation 35.88m), error ≤±2mm, template assembly adopts panel assembly, internal keel fixation, external keel installation and internal corner reinforcement order, the assembled template is connected and fixed by tension bolts;

[0111] S4, concrete pouring, using C30 fiber concrete, advancing from 2-axis to 8-axis along the length of the firewall, layer thickness 450-500mm, slope gradient 1:6-1:8, vibrator inserted 50-55mm into the lower concrete, and re-vibrated twice in the top 450-500mm range;

[0112] S5. Firewall maintenance: spray cement-based penetrating crystalline protective liquid after demoulding, cover with plastic film for moisture maintenance for ≥14 days, humidity ≥90%;

[0113] S6. During the construction of post-cast strips, galvanized corrugated steel mesh (0.8mm thick, 3mm×3mm mesh) is installed on both sides of the post-cast strips and fixed to the main structure by welding with Φ8mm steel bars. A temporary wooden formwork is set on the outside of the steel mesh to prevent deformation caused by the side pressure of the concrete. After pouring, it is covered with plastic film + cotton felt for insulation and curing for 28 days. Watering is done ≥4 times a day in the first 7 days.

[0114] In S2, the scaffolding parameters are as follows:

[0115] The longitudinal spacing of the vertical poles is 1.5 m, the transverse spacing is 0.9 m, and the step distance is 1.8 m;

[0116] The connecting wall members are arranged in the pattern of "two steps and three spans", with a horizontal spacing of 3 m and a vertical spacing of 2.5 m;

[0117] The diagonal braces cover every 4 spans and are ≥ 6 m, with an inclination angle of 45° - 60° to the ground;

[0118] The scaffolding boards are made of bamboo slat boards with a thickness of 50 mm, and the ends are fixed with Φ3.2 mm galvanized iron wire.

[0119] In S3, the specific formwork assembly includes:

[0120] For the panel assembly: Pre-assemble 3 pieces of 2440 mm × 1220 mm composite wood formworks on the ground into a large formwork of 3660 mm × 2440 mm, seal the board joints with double-sided tape, and fill the nail holes with automotive putty;

[0121] For the fixation of the inner joists: The 40×80×4 mm square steel is vertically arranged for 250 mm and connected to the formwork through Φ5 mm countersunk self-tapping screws for 200 mm, and the screws sink into the board surface by ≤ 1 mm;

[0122] For the installation of the outer joists: The channel steel is horizontally arranged for 400 mm and connected to the vertical poles of the double-row scaffolding through Φ48×3.5 mm short steel pipes and right-angle fasteners, and the node spacing is ≤ 500 mm;

[0123] For the corner reinforcement: Set an L-shaped wooden corner formwork (with a thickness of 18 mm) at the intersection of the longitudinal and transverse walls, and weld a square steel diagonal brace of 80×40×4 mm on the back, with a spacing of ≤ 600 mm;

[0124] When connecting and fixing the tie bolts, pre-drill the bolt holes (with a diameter of 22 mm), insert Φ20 mm HPB300 bolts and PVC sleeves, and the two ends of the sleeves protrude from the formwork surface by ≤ 5 mm;

[0125] Installation of the dividing strips: Embed a 100 mm × 10 mm flat iron at the formwork joints, and after removal, a groove is formed, and the groove is coated with gray epoxy resin sealant.

[0126] Apply salad oil release agent to the panel before assembly, spray evenly without flowing; The initial tightening torque is 85 - 90 N·m, and after correcting the verticality (the deviation of the plumb bob is ≤ 3 mm), re-tighten to 100 - 110 N·m; The dividing strips are made of 10 mm thick flat iron, and after removal, a 100×10 mm decorative groove is formed.

[0127] In S4, the pouring of C30 fiber concrete specifically includes:

[0128] Use a concrete pump truck with a boom length of 46m, a pump pipe diameter of 125mm, and an outlet pressure ≥ 12MPa; Pour 50mm thick cement mortar with the same mix ratio at the bottom of each section first; Use ZN50 inserted vibrator, the moving spacing ≤ 400mm, and the distance from the formwork ≤ 150mm; The vibration time is 20 - 30 seconds per point, based on the concrete surface showing slurry and no air bubbles, over-vibration or missed vibration is strictly prohibited; Re-vibrate the top 500mm range within the initial setting time (1 - 2 hours after pouring) to eliminate the water seepage channel; Control the concrete pouring temperature at 5 - 30°C, cover with wet gunny bags in summer to cool down, and use heated mixing water (≤ 60°C) in winter; Immediately cover with plastic film + geotextile after final setting to prevent surface water evaporation, and external loads are prohibited during the curing period;

[0129] The mix ratio of C30 fiber concrete is as follows:

[0130] Cement: P.O42.5 ordinary Portland cement, dosage 380 - 420kg / m 3 ;

[0131] Aggregate: Medium sand with fineness modulus 2.3 - 3.0, mud content ≤ 1%; Crushed stone with particle size 5 - 21.5mm, mud content ≤ 0.5%;

[0132] Admixture: UF500 anti-cracking fiber dosage 0.9kg / m 3 , water reducer dosage 1.2% - 1.5%;

[0133] Slump: 160 - 180mm, initial setting time ≥ 4 hours.

[0134] Furthermore, in S5, the curing of the firewall specifically includes:

[0135] Form removal time: The side form is removed after the concrete strength ≥ 1.2MPa (about 24 hours), and the bottom form waits for the strength ≥ 100% of the design value (tested with the same-condition test block);

[0136] Curing method: Spray cement-based penetrating crystalline protective liquid (two coats of primer + one coat of topcoat), dosage ≥ 1.5kg / m 2 , interval time 4 - 6 hours;

[0137] Environment control: During the curing period, the humidity ≥ 90%, the temperature is 5°C - 35°C, and cover with rainproof cloth in case of rain or snow;

[0138] Within 3 days after form removal, set up a protective railing (height 1.2m) 1m away from the wall to prevent mechanical collision;

[0139] Plug the holes of the tie bolts: Use 1:2.5 dry hard mortar (water-cement ratio 0.38) to fill in three times, with an interval of 24 hours each time, and the surface is troweled smooth and flush with the wall.

[0140] In S6, the construction of the post-cast strip specifically includes:

[0141] Compensated concrete pouring:

[0142] Mix ratio: C35 concrete is mixed with HEA expansion agent (dosage 8% - 10%), and the restricted expansion rate ≥ 0.025%;

[0143] Pouring time: 45 days after the completion of the main structure construction;

[0144] Vibration requirements: Use a combined vibration method of external vibrators + internal vibrators to ensure the compaction behind the steel mesh.

[0145] This construction process also includes safety control of the construction area, quality acceptance standards, intelligent monitoring and BIM collaborative monitoring, and construction environmental protection measures; specifically:

[0146] a. Safety control of the construction area includes:

[0147] Risk grading: Evaluated by the LEC method, the risk value of scaffold collapse D = 126 (Level 3), and the risk value of object strike D = 54 (Level 4);

[0148] Emergency treatment: Set up a warning area, equipped with anti-falling devices, safety nets and fire extinguishers, and the emergency plan covers scenarios of collapse, fire and high-altitude fall;

[0149] Personnel qualifications: Scaffolders, welders and crane operators hold special operation certificates, and the signature rate of technical disclosure is 100%;

[0150] b. Quality acceptance standards include:

[0151] Formwork installation: Axial displacement ≤ 4mm, cross-sectional dimension deviation ± 4mm, surface flatness ≤ 3mm;

[0152] Steel bar works: Main bar spacing ± 10mm, protective layer thickness deviation ± 3mm, straight thread connection torque value ≥ 260N·m;

[0153] Concrete strength: 28-day compressive strength ≥ 34.5MPa, carbonation depth ≤ 2.0mm.

[0154] c. Intelligent monitoring and BIM collaborative monitoring include:

[0155] Use total station to monitor the formwork axis deviation (±5″) and elevation error (±2mm) in real time;

[0156] BIM model simulates the construction process, optimizes the material transportation path and tower crane positioning;

[0157] Use drones to inspect the wall verticality, and upload the data to the cloud analysis platform;

[0158] d. Construction environmental protection measures include:

[0159] The recovery rate of concrete waste ≥ 85%, and the sewage is discharged after being treated to reach the standard in the sedimentation tank;

[0160] During construction, the noise ≤ 70 dB during the day and ≤ 55 dB at night, and the concentration of dust PM10 ≤ 0.5 mg / m 3 ;

[0161] Waste formwork and steel bars are recycled by classification, and the comprehensive utilization rate ≥ 90%.

[0162] Example 3, as Figure 4 shown, a construction technology for the firewall of a UHV converter station. Taking the construction of the firewall of the low-end converter transformer of Pole 1 and Pole 2 and the high-end converter transformer of Pole 1 in the civil engineering Package A project of the Daye ± 800 kV converter station as an example, the firewall is located in the middle of the converter area, including two low-end firewalls of Pole 1 and Pole 2 and one high-end firewall of Pole 1.

[0163] Basic parameters of the wall formwork

[0164] (1) Since the thickness of the firewall on the A-axis side of the high-end converter transformer of Pole 1 is 400 mm, which is the largest, it is taken as the calculation object. The calculated section width is 400 mm and the height is 2440 mm. The formwork panel uses 18 mm wooden formwork.

[0165] (2) The inner keel uses 40×80×4 mm square steel as purlins with a spacing of 250 mm, and the outer keel uses No. 16a channel steel with the U opening horizontal and a spacing of 400 mm.

[0166] (3) Two pairs of pull bolts are arranged, with a horizontal spacing of 2500 mm in the section and a spacing of 400 mm in the section span direction, and the diameter is 20 mm.

[0167] As Figure 5 shown, the standard value of the lateral pressure of newly poured concrete on the formwork:

[0168] G 4k＝ min[0.22γ c t0β1β2v 1 / 2, γ c H] = min[0.22×24×4×1.2×1×2 1 / 2, 24×2.54] = min[35.84, 60.96] = 35.84 kN / m 2 ;

[0169] S 承 = γ0×(1.3G 4k +γ L ×1.5Q 4k) = 1×(1.3×35.842 + 0.9×1.5×2.000) = 49.29 kN / m 2 ;

[0170] Design value S under serviceability limit state 正 = G 4k = 35.842 kN / m 2 .

[0171] I. As shown Figures 6 to 9 below, check the formwork panel

[0172] The width of the wall section can be any width. For the convenience of checking the main beam, take:

[0173] b = 0.4 m

[0174] W = bh 2 / 6 = 400×18 2 / 6 = 21600 mm 3

[0175] I = bh 3 / 12 = 400×18 3 / 12 = 194400 mm 4

[0176] Strength check

[0177] q = bS 承 = 0.4×49.295 = 19.718 kN / m

[0178] M max＝ 0.154 kN·m

[0179] σ = M max / W = 0.154×10 6 / 21600 = 7.132 N / mm 2 ≤ [f] = 15.444 N / mm 2

[0180] The requirement is satisfied.

[0181] Deflection check

[0182] q = bS 正 = 0.4×35.842 = 14.337 kN / m

[0183] ν = 0.401 mm ≤ [ν] = l / 400 = 250 / 400 = 0.625 mm

[0184] The requirement is satisfied.

[0185] II. As shown Figures 10 to 14 below, check the secondary joist

[0186] Strength check

[0187] q = bS 承 = 0.315 × 49.295 = 15.528 kN / m

[0188] Mmax = 0.263 kN·m

[0189] σ = Mmax / W = 0.263×10^6 / 16200 = 16.205 N / mm2 ≤ [f] = 205 N / mm2, requirements are met.

[0190] Deflection check

[0191] q = bS positive = 0.315 × 35.842 = 11.29 kN / m

[0192] ν = 0.014 mm ≤ [ν] = l / 400 = 400 / 400 = 1 mm

[0193] Requirements are met.

[0194] Calculation of support reaction

[0195] R1 = 5.031 kN, R2 =...R9 = 5.59 kN, R10 = 7.043 kN

[0196] III. As Figures 15 to 18 , Main keel check

[0197] Strength check

[0198] M max＝ 16.798 kN·m

[0199] σ = M max / W = 16.798×10 6 / 10800 = 155.538 N / mm 2 ≤ [f] = 205 N / mm 2

[0200] Requirements are met.

[0201] Deflection check

[0202] ν = 4.237 mm ≤ [ν] = l / 400 = 2440 / 400 = 6.1 mm

[0203] Requirements are met.

[0204] IV. As Figure 19 shown, check of tie bolts

[0205] Transverse check spacing of tie bolts m = max[400, 400 / 2 + 100] = 400 mm

[0206] Vertical check calculation spacing n of the tie bolts = max[2440, 2440 / 2 + 50] = 2440 mm

[0207] N = 0.95mnS 承 = 0.95×0.4×2.44×49.295 = 45.706 kN ≤ N t b = 47.9 kN

[0208] The requirements are met.

[0209] 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 the present invention 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 construed as limiting the claims involved.

[0210] 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 firewall for a UHV converter station, comprising a reinforced concrete shear wall (1), characterized in that: The wall of the reinforced concrete shear wall (1) is provided with a post-cast strip (2), and the top of the reinforced concrete shear wall (1) is cast with an overhanging eave (3) and a gutter (4), and the gutter (4) is located at the upper end of the overhanging eave (3); When the reinforced concrete shear wall (1) is cast, a combined steel frame-wood formwork assembly is constructed. The combined steel frame-wood formwork assembly comprises a composite wood formwork, a square steel inner keel and a channel steel outer keel. The formwork and the keel of the combined steel frame-wood formwork assembly are connected and fixed by tension bolts. The post-cast strip (2) is arranged in the middle of the wall. During the casting process, the post-cast strip (2) is isolated from the shear wall bodies on both sides by a galvanized corrugated steel plate mesh.

2. The firewall of a UHV converter station according to claim 1, characterized in that: The reinforced concrete shear wall (1) comprises a low-end fire wall and a high-end fire wall; The width of the post-cast strip (2) is 800-1000 mm. When pouring the post-cast strip (2), an independent formwork is built. The thickness of the galvanized corrugated steel mesh used in the formwork on both sides is 0.5-0.7 mm, and the mesh size is 3-5 mm. The strength grade of the shrinkage compensating concrete is C35, and the expansion rate is limited to ≥0.025%. The pouring time of the post-cast strip (2) is 45-50 days after the main structure concrete of the reinforced concrete shear walls (1) on both sides is cured. The reinforced concrete shear wall (1) has a combined steel frame-wood formwork assembly constructed when the wall is cast, and a PE rubber cotton strip is embedded in the formwork joint; the square steel inner keel is arranged vertically and fixed to the formwork by countersunk self-tapping screws, the spacing between the square steel inner keels is 230-270 mm, and the spacing between the screws is 150-200 mm; the channel steel outer keel is arranged horizontally and connected to the scaffolding by short steel pipes and right-angle fasteners, and the spacing between the channel steel outer keels is 350-450 mm; The tension bolts are M20 high-strength bolts with a horizontal spacing of 350-450mm and a vertical spacing of 2400-2600mm. The two ends of the tension bolts are threadedly connected with double nuts for locking, and the bolt ends are sleeved with PVC sleeves. The bolt tensile strength design calculation formula is: N = 0.95 × m × n × S 承 ≤ N t b Among them, S 承 is the design value of the lateral pressure; A drip line is arranged at the end of the eaves (3), and the drip line is 45-55 mm away from the edge of the wall; and the eaves (3) are supported by steel pipe diagonal braces, and the bottom is anchored at the tension bolts; A downpipe opening is pre-buried at the bottom of the gutter (4).

3. Construction process of a firewall for an UHV converter station, including the firewall for an UHV converter station according to any one of claims 1 to 2, characterized in that, The construction process comprises the following steps: S1. Construction section division: According to the height of the firewall, the location of the structural variable section and the construction load transfer path, the principle of "vertical segmentation and horizontal continuity" is adopted to reduce the impact of construction joints on integrity. The low-end firewall is divided into 9 sections and the high-end firewall is divided into 13 sections. The height of the first floor is 1.6m, the middle layer is 2.5m, and the top layer is 1.15m to 1.35m. The low-end firewall adopts the "two-shift" mode, and the construction period of each section is 5 days. The high-end firewall is inserted into the construction of the low-end to the 4th section, and the tower crane is used to transport materials vertically. The construction period of each section is extended to 6 days to ensure that there is no conflict in the connection of the process. The horizontal construction joint is left at the top of each section. S2. Scaffold installation. The formwork bent is used as the construction operation scaffold for the erection of the scaffold body. Steel pipe fastener scaffolds are adopted and are erected in a closed manner along the perimeter of the firewall. On the side of the valve hall of the back wall of the high-end firewall, double-row double vertical poles are used, with an erection height of 31 m; on the side of the converter transformer of the back wall, triple-row double vertical poles are used, with an erection height of 32 m; for the partition wall, double-row single vertical poles are used, with an erection height of 13 m; on the side of the valve hall of the back wall of the low-end firewall, double-row single vertical poles are used, with an erection height of 21 m; on the side of the converter transformer of the back wall, triple-row single vertical poles are used, with an erection height of 22 m; for the partition wall, double-row single vertical poles are used, with an erection height of 13 m; S3. Formwork installation, axis and elevation control. The total station is used to review the axis, which is surveyed from the reference control network; the level is used to set the elevation, and elevation control points are set at the top of each section. When assembling the formwork, the construction is carried out in the order of panel assembly, inner keel fixation, outer keel installation, and internal corner reinforcement. The assembled formwork is connected and fixed by tie bolts; S4. Concrete pouring. C30 fiber concrete is adopted and is advanced from Axis 2 to Axis 8 along the length of the firewall. The layered thickness is 450 - 500 mm, the slope gradient is 1:6 - 1:8, the vibrating rod is inserted 50 - 55 mm into the lower layer of concrete, and the top layer is vibrated again within the range of 450 - 500 mm; S5. Firewall maintenance. After form removal, a cement-based penetrating crystalline protective liquid is sprayed, and plastic film is covered for moisture conservation maintenance for ≥14 days, with a humidity of ≥90%; S6. Post-cast strip construction. Galvanized corrugated steel mesh is installed on both sides of the post-cast strip and is fixed by welding with the main structure through steel bars; a temporary wooden formwork support is set outside the steel mesh to prevent deformation caused by the lateral pressure of the concrete. After pouring, plastic film + cotton felt is covered for heat preservation maintenance for 28 days, and water is sprinkled ≥4 times a day in the first 7 days.

4. The construction process according to claim 3, characterized in that: In the above S2, the parameters of the scaffold are as follows: The longitudinal spacing of the vertical poles is 1.5 m, the transverse spacing is 0.9 m, and the step distance is 1.8 m; The connecting members are arranged according to "two steps and three spans", with a horizontal spacing of 3 m and a vertical spacing of 2.5 m; The diagonal braces cover every 4 spans and ≥6 m, and the angle with the ground is 45° - 60°; The scaffold boards are 50 mm thick bamboo stringer boards, and the ends are fixed with Φ3.2 mm galvanized iron wire.

5. The construction process according to claim 3, characterized in that: In the above S3, the specific formwork assembly includes: For panel assembly: 3 pieces of 2440 mm × 1220 mm composite wood formworks are pre-assembled on the ground into a 3660 mm × 2440 mm large formwork. The joints are sealed with double-sided tape, and the nail holes are filled with automotive putty; For inner keel fixation: The 40×80×4 mm square steel is vertically arranged at 250 mm and is connected to the formwork by Φ5 mm countersunk head self-tapping screws for 200 mm, and the screws sink into the formwork surface by ≤1 mm; For outer keel installation: The channel steel is horizontally arranged at 400 mm and is connected to the double-row scaffold vertical poles by Φ48×3.5 mm short steel pipes and right-angle fasteners, and the node spacing is ≤500 mm; For internal corner reinforcement: L-shaped wooden corner forms are set at the intersection of the longitudinal and transverse walls, and 80×40×4 mm square steel diagonal braces are welded on the back, with a spacing of ≤600 mm; When the tie bolts are connected and fixed, the bolt holes are pre-drilled, and Φ20 mm HPB300 bolts and PVC sleeves are inserted. The two ends of the sleeves protrude from the formwork surface by ≤5 mm; Partition bar installation: Embed a 100mm×10mm flat iron at the template joint. After removal, a groove is formed, and gray epoxy resin sealant is applied in the groove.

6. The construction process according to claim 5, characterized in that: Before assembling the panel, apply salad oil release agent, spray evenly without running; the initial tightening torque is 85 - 90N·m, and after correcting the verticality, re-tighten to 100 - 110N·m; the partition bar is made of 10mm thick flat iron, and after removal, a 100×10mm decorative groove is formed.

7. The construction process according to claim 3, characterized in that: In S4, the pouring of C30 fiber concrete specifically includes: Use a concrete pump truck with a 46m boom length, the pump pipe diameter is 125mm, and the outlet pressure ≥ 12MPa; first pour 50mm thick cement mortar with the same mix ratio at the bottom of each section; use a ZN50 inserted vibrator, the moving spacing ≤ 400mm, and the distance from the formwork ≤ 150mm; the vibration time is 20 - 30 seconds per point, based on the concrete surface showing slurry and no air bubbles, over-vibration or missed vibration is strictly prohibited; in the top 500mm range, perform secondary vibration before the initial setting to eliminate the water seepage channel; control the concrete pouring temperature within 5 - 30℃, cover with wet gunny bags in summer to cool down, and use heated mixing water in winter; immediately cover with plastic film + geotextile after final setting to prevent surface water evaporation, and external loads are prohibited during the curing period; The mix ratio of C30 fiber concrete is: Cement: Ordinary Portland Cement P.O42.5, dosage 380 - 420 kg / m 3 ; Aggregate: Medium sand fineness modulus 2.3 - 3.0, mud content ≤ 1%; crushed stone particle size 5 - 21.5mm, mud content ≤ 0.5%; Admixtures: The dosage of UF500 anti-cracking fiber is 0.9 kg / m 3 , and the dosage of water reducer is 1.2% - 1.5%; Slump: 160 - 180mm, initial setting time ≥ 4 hours.

8. The construction process according to claim 3, characterized in that: In S5, the curing of the firewall specifically includes: Form removal time: Remove the side formwork after the concrete strength ≥ 1.2MPa, and remove the bottom formwork when the strength ≥ 100% of the design value; Maintenance method: Spraying cement-based penetrating crystalline protective liquid, dosage ≥ 1.5 kg / m 2 , interval time 4 - 6 hours; Environmental control: During curing, the humidity ≥ 90%, the temperature is 5℃ - 35℃, and cover with a rainproof cloth in case of rain or snow; Within 3 days after form removal, set up a protective railing 1m away from the wall to prevent mechanical collision; Seal the holes of the tie bolts: Fill with 1:2.5 dry hard mortar in three times, with an interval of 24 hours each time, and the surface is polished to be flush with the wall.

9. The construction process according to claim 3, characterized in that: In S6, the construction of the post-cast strip specifically includes: Pouring of compensating concrete: Mix ratio: C35 concrete is added with HEA expansion agent, and the restricted expansion rate ≥ 0.025%; Pouring time: 45 days after the completion of the main structure construction; Vibration requirements: Use a combined vibration of an attached vibrator + an inserted vibrator to ensure the density behind the steel mesh.

10. The construction process according to claim 3, characterized in that: The construction process also includes safety control of the construction area, quality acceptance standards, intelligent monitoring and BIM collaborative monitoring, and construction environmental protection measures; specifically: a. Safety control of the construction area includes: Risk grading: Evaluate using the LEC method, the risk value of scaffold collapse D = 126, and the risk of object hitting D = 54; Emergency treatment: Set up a warning area, equipped with anti-falling devices, safety nets and fire extinguishers, and the emergency plan covers scenarios of collapse, fire, and high-altitude fall; Personnel qualifications: Scaffolders, welders, and crane operators hold special operation certificates, and the signature rate of technical disclosure is 100%; b. Quality acceptance standards include: Formwork installation: Axial displacement ≤ 4mm, cross-sectional dimension deviation ± 4mm, surface flatness ≤ 3mm; Reinforcement works: The spacing of main reinforcement bars is ±10 mm, the deviation of the cover thickness is ±3 mm, and the torque value of the straight thread connection is ≥260 N·m; Concrete strength: The 28-day compressive strength is ≥34.5 MPa, and the carbonation depth is ≤2.0 mm. c. Intelligent monitoring and BIM collaborative monitoring include: Using a total station to monitor the axis deviation and elevation error of the formwork in real time; The BIM model simulates the construction process to optimize the material transportation path and tower crane positioning; The unmanned aerial vehicle inspects the wall verticality, and the data is uploaded to the cloud analysis platform; d. Construction environmental protection measures include: The recovery rate of concrete waste is ≥85%, and the sewage is discharged after being treated up to standard in the sedimentation tank; During construction, the noise level should be ≤70 dB during the day and ≤55 dB at night, and the concentration of PM10 dust should be ≤0.5 mg / m 3 ; The waste formwork and steel bars are classified and recycled, and the comprehensive utilization rate is ≥90%.

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