Steel structure corridor construction process

Steel structure corridor construction process

Steel structures should study high-strength steel to greatly increase its yield point strength; in addition, new types of steel should be rolled, such as H-shaped steel (also Wide flange steel) and T-shaped steel and profiled steel plates to meet the needs of long-span structures and super high-rise buildings. Below I will share with you the construction plan process of the steel structure corridor. You are welcome to read and browse.

Steel structure corridor construction method 1

Comprehensive description and project overview

This indoor cantilevered steel structure corridor is located in the boiler room of Huaneng Nong'an Biothermal Power Plant Inside, in order to facilitate the opening and closing of windows, cantilevered steel structure corridors on the east and west sides are added. The length of the corridor is approximately 35.00 meters, the overhang width is 0.9 meters, the bottom elevation of the corridor is 21.00 meters, and the construction area of ??the corridor is approximately 63.00㎡ (see the attached picture for the method). The safety level of this steel structure corridor is Level 2, the fire resistance level is Level 2, and the main components are made of Q345 and Q235 steel. The original fixed glass windows on the west side of the boiler room at an altitude of 21.8 meters and on the east side at an altitude of 21.8m and 18.8m were removed and replaced with 90 series plastic steel gauze sliding windows (see the 07J604 standard atlas for practice). The area of ??the gauze plastic steel windows is approximately It is 129.6㎡.

Construction preparation

1. Organize relevant project management and technical personnel to conduct a joint review of the drawings. For areas where the drawings are not clear and where there are difficulties in construction, change verification procedures must be carried out.

2. Based on the construction drawings and the unit’s equipment and technical conditions, formulate a construction plan for the project and propose a material plan.

3. Inspect the performance of machinery and testing equipment used in steel structures and plastic steel window projects to ensure that various equipment are in good working condition and have complete functions during the construction process.

4. In addition to having quality certificates, the materials used in steel structures and plastic steel window projects should also be retested in accordance with the provisions of current national standards. They can only be used if they meet the standards.

5. Before the construction of steel structures and plastic steel windows, necessary on-the-job training should be provided to construction personnel in each process, and technical, quality, and safety briefings should be conducted to prevent safety and quality accidents.

6. When the steel structure plastic windows enter the site, the components must be inspected and reasonably stacked to facilitate smooth installation of the components after entering the site.

Construction schedule

Based on the conditions of Huaneng Nong'an Biothermal Power Plant and the actual difficulty of the project. The specific arrangement and node progress control are as follows:

2 days for construction preparation - 5 days for material procurement and processing factory cutting and production - 2 days for on-site scaffolding - on-site assembly and welding of the corridor 5 days - 6 days for the production and installation of the plastic steel windows on the corridor, and 20 days for full delivery.

Labor force plan

Based on the actual situation of the project, the on-site labor force will be deployed in a timely manner, and the staff will be fully equipped according to the type of work, level and project content. The overall plan to dispatch the labor force of each type of work is as follows:

There are 4 cutting workers, 4 assemblers, 2 welders, 3 shelf workers, 2 painters, and 4 door and window installers.

Main construction machinery preparation

Drilling machines, automatic profile steel assembly machines, band saws and other large-scale production machines are all equipped and used in the processing plant.

The site is equipped with an arc welding machine, a set of oxygen welding and cutting equipment, and a 25-ton crane. A rocking drill, a hand-held electric drill, and a grinding wheel cutting machine.

Steel structure corridor production and installation construction methods

1. Steel structure corridor production:

1. The steel selected for this structure must be factory-qualified certificate and original data, and it is also required that the steel entering the factory must pass the retest before it can be used.

2. Choose processing equipment with good performance and full functions.

3. The welding rod should have a factory certificate or material report. It is required that the welding rod should be dried in a drying oven before use. The welding wire and flux selected for submerged arc welding must match the base metal used.

4. This steel component needs to be shot blasted and derusted after it is completed. It is required to apply primer within 24 hours after derusting. The primer should be sprayed. It is required to ensure that the paint film thickness meets the design. Require.

5. All operators must strictly follow the technical, quality and safety briefings, and welding personnel must hold certificates to work.

6. The butt welds required for this steel structural steel must undergo ultrasonic flaw detection testing, and the testing level is Level 2.

7. In order to improve the accuracy of hole making, drill molding is used to make holes in the steel structure. The drill sleeve is made of medium carbon steel and must be quenched. The diameter of the inner hole of the drill mold should be 0.3MM larger than the designed hole diameter. The thickness of the drill mold should not be too large, generally about 15MM.

8. In order to ensure the manufacturing accuracy, the shrinkage amount must be pre-shrunk when cutting steel components. The pre-shrinkage amount depends on the size of the workpiece. Generally, the workpiece is 40-60mm. Important, large and long workpieces must be pre-shrunk. Put 80-100mm.

9. It is essential to formulate a reasonable welding sequence. When several types of welds are to be welded, the transverse seams with larger shrinkage and deformation should be welded first, and then the longitudinal welds, or welded first. Butt welds and then fillet welds.

10. The main weld of welded steel should be welded before assembling the stiffening floor parts. The welding sequence of the main welds should be staggered according to the need for post-weld deformation.

2. Installation of steel structure corridors:

1. The steel structure hoisting process strictly follows the "GB50205-95 Steel Structure Construction and Acceptance Specifications" and "GB50221-95 Steel Structure Engineering Quality" Inspection and Assessment Table Standards"

2. Before starting construction, the vertical and horizontal axes and horizontal elevations, the overall dimensions of steel components, and the welding quality must be re-inspected before construction.

3. Technical briefing must be conducted before construction.

4. Special personnel employed during construction must have an employment certificate issued by the Labor Bureau.

5. Measuring instruments must be qualified through metrological verification before they can be used.

6. Adhere to the three inspections (self-inspection, mutual inspection, professional inspection) system during construction and strictly inspect process quality.

Manufacturing and installation methods of plastic steel doors and windows

1. Profile blanking: The length should consider the welding allowance and need to be increased by 6mm. The length error is ±5mm and the angle error is ±5°.

2. Milling drainage holes and air pressure balance holes: Whether sliding windows, inward opening windows or outward opening windows should be equipped with drainage holes and air pressure balance holes. Drainage holes and air pressure balance holes cannot be opened at will. They must be opened according to the Specification requirements open. The size of the drainage hole is Φ×L (5mm×30mm); the size of the air pressure balance hole is Φ×L (4.5mm×30mm).

3. Mill the hardware mounting slots.

4. Cutting and assembly of reinforced steel: Function: Improve the rigidity and strength of doors and windows, prevent profile deformation; make the installed hardware stronger. Technical requirements: wall thickness ≥1.2mm, fit gap should be 1±0.5mm, reinforced steel requires smooth internal and external surfaces, no cracks, delaminations, lap welding defects are allowed; smooth appearance, clear edges and corners, and no burrs. Cutting and assembly of reinforced steel: Principles for additional installation:

a. Determined by calculation,

b. Frames, fans, and stiles that need to be installed with hardware;

c. When the length of the main profile is greater than 450mm. The distance between the reinforced steel and the end of the profile should not be greater than 15mm; the number of connecting fasteners used to fix each reinforced steel should not be less than 3, with a spacing of ≤300mm and a distance of ≤100mm from the end of the reinforced steel. The fixed reinforced steel shall not loosen.

5. Profile welding: mainly controls welding temperature, clamping pressure, melting pressure, butt pressure, melting time, butt time, etc.

6. Welding flash cleaning.

7. Installation of sealing strips: There are O-type and K-type sealing strips. O-type is used for sealing between the frame and the sash, and K-type is used for sealing between the glass and the bead; each The ends of the sealing strips in each frame should be located in the middle of the upper frame. The sealing strips at each corner should be cut with scissors to make the sealing strips flat at right angles. It is strictly prohibited to cut the strips. The strip should be smooth without curling or slipping.

8. Selection and installation of hardware accessories: Whether the opening and closing of doors and windows is tight and flexible depends on the quality of the installation of hardware, especially the installation of handles, lock points, and sliding braces. Stainless steel sliding stays must be connected with stainless steel screws.

9. Glass assembly: It is recommended that the glass be edged to prevent the glass from breaking during production, transportation and use. The ambient temperature of glass installation should be above 15C. Glass spacers must be added when installing glass, and the glass must not be in direct contact with the frame or fan; the cutting length of the glass beading should be accurate to ensure that the corner joints are ≤ 1mm.

10. Installation of window frames: The position of the fixed points of the window frame is a=150~200mm from the corners of the door and window, the middle mullion frame, and the middle horizontal frame. The spacing between the fixed points is l≤600mm. The fixed points must not be The piece (expansion bolt) is directly installed on the end of the middle horizontal frame or middle mullion frame. A 10mm gap should be left between the window frame and the attached frame. The gap between the window frame and the attached frame should be sealed with foam glue to ensure the thermal insulation performance of the plastic steel window and its ability to expand and contract freely when the temperature changes. The lower frame should be fixed using fixing pieces as much as possible to reduce the risk of water leakage.

11. Note on foam glue and sealant: The gap between the window frame and the opening must be sealed with polyurethane foam glue. The foam glue filling should be even and dense; before construction, it should first be filled with polyurethane foam glue. The baffle blocks the outside of the gap, and foam is applied inside. After 10 to 15 minutes, the overflowing foam is flattened into the frame. Do not cut it with a knife. After the temporarily fixed wooden wedges are removed, they must also be sealed with foam glue. . The injection of sealant should be done by experienced personnel and should be smooth and flat.

Safety construction measures

1. Set up a safety foreman at the construction site to implement and manage on-site safety measures, and conduct unified management of on-site construction personnel, on-site machinery and equipment, and on-site electricity consumption. Special agents required to participate in construction must be trained and certified. Conduct safety technical briefings for all construction personnel before construction. Personnel entering the construction site must wear safety helmets and non-slip shoes. Electricians and electrical welders should wear insulating shoes, and safety belts must be fastened when working at heights.

2. The tools, machinery, and equipment used should be inspected before work, and the safety devices should be complete and effective.

3. The operating surface should have a reliable platform to protect the body, and the operation should be carried out after inspection. The binding method of components should be correct, and anti-slip measures should be taken at lifting points. Tools and materials used for high-altitude operations should be placed in a safe place and are not allowed to be placed casually.

4. When lifting steel components, the lifting or lowering should be smooth and avoid emergency braking or impact. Dedicated personnel are responsible for command, and the signals are clear, loud, and unambiguous. Illegal operations are strictly prohibited. After the components are installed, their quality must be checked to ensure that they are safe and reliable before being unfastened. Work must reach a safe position every day before calling it a day.

5. The mechanical and electrical equipment, gate boxes, and welding machines at the construction site should have reliable rainproof measures. The operation of electrical appliances must be carried out by professionals, and operation by non-professionals is strictly prohibited. The electric welding machine uses strict safety operating procedures. The primary wire must not exceed 2 meters, and the secondary wire must not be broken or exposed.

6. Safety facilities are set up uniformly by dedicated personnel in accordance with regulations, and others are not allowed to dismantle them at will. When it needs to be dismantled due to work needs, permission must be obtained from the relevant personnel. It must be restored in a timely manner afterwards and safety personnel must carefully inspect it.

7. Ensure safe use of electricity. Professional electricians are responsible for the removal of all electrical equipment and on-site lighting. All power tools used must be equipped with leakage protectors.

8. Focus on controlling high-altitude operations. Drinking and joking are strictly prohibited during work. Hand-held tools should be fastened with safety lanyards to avoid straight and vertical crossing operations.

9. Fire prevention must be ensured, and all operations should be used correctly and in accordance with regulations.

10. When installing the roof, a safety net should be arranged and railings should be installed.

11. Adhere to the pre-shift safety meeting system and explain the day’s work arrangements and safety precautions.

12. Conduct regular safety inspections to prevent and control unsafe factors in accidents.

13. Lifting instructions must be decisive and instructions must be concise and clear.

14. Strengthen on-site security and pay attention to fire and theft prevention.

15. A safety cordon is set up within the hoisting operation range, and non-operators are prohibited from entering.

16. All safety activity records and documents must be complete

On-site civilized construction measures

1. Internal industry requirements for various information and accounts (construction plans, Safety education, safety briefings, safety inspections, electrician daily inspection records, pre-shift speech records, ledgers, etc. are complete and neat, and the records are realistic. Special operations must be carried out with certificates, and safety responsibilities are clearly divided.

2. Wear a safety helmet when entering the site and wear a safety belt when working at heights. The safety net is tightly supported in accordance with regulations. There are protective sheds at the entrance and exit, and there are safe passages in small sites.

3. Electrical equipment should be equipped with three levels of control and two levels of protection (main gate box, distribution box, switch box, and matching electric shock protectors in the distribution box and switch box). The gate boxes should be standardized and the lines should be standardized. There are records of electrician inspections and side shaking.

4. This project is equipped with colored fences to carry out civilized construction management on site. There are clear publicity slogans on site and standard color signs hung at dangerous locations.

5. The site has flat and clean channels that are not blocked or accumulate water, and construction wastewater is properly discharged through drainage ditches.

6. Civilized construction will not disturb residents, strictly control construction noise, and stop construction after 10 p.m.

7. Do not occupy roads illegally, do not pile objects illegally, do not cause fires or traffic accidents, do not damage public facilities in violation of regulations, do not pollute the environment, and do a good job with relevant departments inside and outside the site. Cooperate.

Construction process flow of lattice columns

Operation process:

1. Staking out and numbering of lattice columns: The grids shall be constructed in accordance with the design requirements. Clean the raw materials before cutting, reserve appropriate welding shrinkage allowance and cutting allowance, and save materials as much as possible.

2. Assembling and welding of lattice columns: If the lattice columns are long and difficult to transport, the lattice columns should be assembled and welded in sections. Ensure the verticality of the lattice columns.

3. Hoisting, transportation and stacking of lattice columns: Use a crane to lift steel lattice columns, and lift them slowly and with care.

4. Installation and positioning of lattice columns: After the lattice columns are hoisted into the pile holes, they are firmly welded to the steel cage. The welding between the main bars of the steel cage and the lattice columns must be reliable and firm, and the overlap length must be in accordance with the specifications. The welding requirements are consistent with those of engineering piles and must meet specification requirements.

Quality requirements:

1. Raw materials: angle steel and steel plates for lattice columns must be purchased in strict accordance with the drawings and specifications, and must have factory certificates and test reports.

2. Welding requirements: The welding requirements for lattice columns are relatively high. The weld surface should be uniform and smooth, without wrinkles, interruptions and incomplete welds, and should be smoothly connected to the base metal. Cracks, slag inclusions, etc. are strictly prohibited. Defects such as welding flash, burn through, arc craters, needle holes and fusion spatter.

3. Quality points of installation: In order to ensure the verticality of the steel columns, the verticality of the lattice columns must be monitored during installation. The steel columns must have reliable connections with the steel cages and the pipes must be connected with the pile construction technology. Carry out concrete pouring for columns. ;