Step 1: Cutting
Cut steel plate into pieces and connections by flame cutting machines (CNC, Semi-automatic flame cutting machines). Long strips will be used as web and flange plate, connections will be used as connected, reinforced or stiffening plate.
Step 2: Assembly
Combine web and flange plate together through H-beams assembly machine, make tack welding. Keep the web plate in the middle line, do not be off the center line.
Step 3: Gantry automatic submerged arc welding
Make welding by gantry submerged arc welding machine. Make sure the welding sequence and reduce the welding deformation.
Step 4: Flange plate of straightening
Start straightening on welding-finished H steel beams by straightening machine.
Step 5: Connections process
Make holes on connected pieces by drilling machines. Make sure the hole size and precision.
Step 6: Welding
Welding with CO2. Make sure the weld quality without welding flaw.
Step 7: Shot blasting
Make shot blasting on steel profiles. Make sure the blasting grade and quality.
Step 8: Spray painting
Painting or other anti-corrosion surface treatment.
Step 9: Package & Loading
Pack steel structure profiles on steel pallet, which will be easy for loading, transportation and unloading jobs.
Industrial steel building is easy to move and recycle without pollution. These are stronger than traditional workshops, and the walls of the steel structure workshops can also be filled with bricks, which are completely load-bearing. All future plant constructions will be steel structure plants. Here we are going to introduce the steps of installing Industrial steel building.
What are the raw materials used in industrial steel building?
What is the main installation process of industrial steel building?
What is the production and installation process of industrial steel building?
In addition to iron and carbon, the raw materials of industrial steel building also contain other elements. Divided into permanent elements; occasional elements; hidden elements and alloying elements. The common elements are manganese, silicon, sulfur, and phosphorus. Incidental elements are due to the different origins of ore (there are intergrowth ore mixed with iron) and scrap steel as raw materials, such as copper, titanium, vanadium, rare earth elements, etc., are brought into steel during smelting and process operations. The cryptic elements refer to non-metal elements with a small atomic radius, such as oxygen and hydrogen. Alloying elements refer to elements specially added to change the composition, such as chromium, nickel, tungsten, molybdenum, vanadium, etc.
Carbon steel (referred to as carbon steel) is an iron-carbon alloy with a carbon content of more than 0.0218% and less than 2.11%. Because carbon steel has good mechanical properties and process properties, and is large in output and low in price, it is a metal material that is widely used in mechanical engineering. However, carbon steel also has some shortcomings, such as low hardening energy, poor temper softening resistance, and low yield ratio. The strength potential of carbon steel cannot be fully utilized even after heat treatment. In order to meet the continuous development of modern industry and science and technology, alloy steel was developed.
Foundation → production and installation foundation is divided into (foundation ground survey → foundation excavation → embedded screws → foundation casting → later foundation grouting → outdoor water dispersion → outdoor drainage ditch (some factory design indoor drainage ditch or cable ditch suggestion Completed simultaneously with installation)→Enclosure masonry→tiling tiles, etc.)
The production and installation are divided into (processing production→component painting→structural pre-assembly→steel component hoisting→main structure adjustment→purlin installation→door and window column installation→gutter downpipe installation→steel component painting (some are fireproof, some are Anti-corrosion, according to design requirements) → roof panel (some with steel mesh, some with insulation layer, completed at the same time) → wall panel installation → door and window installation → water supply and drainage installation → electrical equipment installation)
Qingdao Xinguangzheng Steel Structure Co., Ltd., as a Chinese pioneer in producing Industrial steel buildings, can ensure the products’ quality and the after-sales service.
Steel building accessories has the advantages of overall light weight, saving foundation, less materials, low cost, short construction period, large span, safety and reliability, beautiful appearance and stable structure. Steel structure workshop is widely used in construction industries such as long-span industrial workshop, warehouse, cold storage, high-rise building, office building, multi-storey parking lot and residential house.
How to use the machine to remove the rust spots on the surface of Steel building accessories?
What are the main Steel building accessories?
How to remove the rust spots on the surface of Steel building accessories?
For Steel building accessories that have been used for a period of time, there are inevitably some attachments on the surface, such as rust, dirt, dust, old paint film, etc. Before painting the surface of Steel building accessories, if these attachments are not completely removed, although they can be temporarily covered after painting, they play a role of isolation, which makes the coating and the component substrate bond If the strength is severely reduced, the paint film will fall off prematurely, which will eventually reduce the corrosion resistance of the surface coating and fail to play the protective role of the coating. Therefore, before painting the surface of the component, the attachments on the surface of Steel building accessories should be thoroughly cleaned.
In order to improve the quality of rust removal and work efficiency. To improve the working conditions of construction workers, the current Steel building accessories derusting work has adopted a large number of wind-driven or electric small equipment. The main rust removal methods using equipment are:
(1) Angle grinder: This small pneumatic equipment is mainly used to clean flat areas. It can use sandpaper, grinding wheels and wire brushes as needed.
(2) Needle Bundle Derusting Machine: This kind of small pneumatic equipment is generally equipped with 30-40 needle bundles, which can be adjusted with different working surfaces, which are mainly suitable for curved, narrow, uneven and cracked places.
(3) Single-head cold air gun: This small pneumatic equipment is also called zinc knocking. It uses the impact of the knocking head to remove rust. The diameter of the shovel head is generally 25-40mm, and it can impact 1000 to 6000 times per minute. Suitable for relatively narrow places.
1. Two-hole connection accessories
One of the main accessories of Steel building accessories is the double-hole connection accessory, which is mainly used to connect with the corners. The corners on both sides of the right-angle connection can reduce the pressure on the alloy. At the same time, the recesses of the building materials can be based on the aluminum alloy frame.
2. Single hole connector
Steel building accessories also has an important accessory, the single-hole connector, which has a completely different function from the double-pipe connector. It is mainly used for the affinity connection between the aluminum alloy frame and the ground in the ground installation. Therefore, the single-hole connector has The role of anchor bolts.
The Steel building accessories have been widely used in daily life and industrial production. Qingdao Xinguangzheng Steel Structure Co., Ltd. can provide the best Steel building accessories for their customers.
Residential steel building has entered a new stage of development. Relevant specifications and design standards have been issued and implemented one after another. In addition, the supply of steel is sufficient. A batch of Residential steel building trial construction experience and scientific and technological achievements continue to be presented. The development of Residential steel building Have a good material and technical foundation
How will Residential steel building develop in the future?
What should be considered before building Residential steel building?
What are the issues that need to be considered when constructing Residential steel building?
Due to the flexibility of Residential steel building design, in addition to high-rise buildings, low- and multi-storey residential buildings also have good adaptability for the residential system. At the same time, the development of villas in low- and multi-storey houses can use light steel structures such as cold-formed C-shaped steel or Small hot-rolled steel forms a keel structure system; high-rise buildings can use hot-rolled H-shaped, welded H-shaped, welded box-shaped, cold-formed thin-walled square steel pipe filled with concrete, round steel pipe filled with concrete, etc. to form a steel frame body and steel support frame system , Steel frame concrete shear wall system, etc.; while building villas and rural buildings, wall column systems can be used.
1. The cooperation between building equipment and Residential steel building is the first problem encountered by residents. Therefore, how to use advanced technology to develop various equipment suitable for steel structure residence is a problem we must solve.
2. The cost of Residential steel building is the most concerned issue of real estate developers. Steel structure residence should be located in medium and high-grade residence. Steel structure residence building is a systematic project. Management and coordination should be strengthened from the links of design, manufacturing, transportation, installation, maintenance and management, so as to reduce costs and improve comprehensive economic benefits.
1. Selection and development of exterior wall panels for Residential steel building is one of the key issues in the promotion of steel structure residential buildings. In addition to meeting the technical requirements of exterior wallboards, it is also necessary to make wallboard raw materials suitable for local conditions, work-oriented production, transportation, installation and connection.
2. The structure of Residential steel building should be safe and reasonable, the node structure should be convenient and reliable, and create conditions for component production, transportation and hoisting.
3. The seismic performance of Residential steel building has a lot to do with the regularity of structural layout. The structure layout is irregular, it is easy to be damaged during an earthquake, and in addition to the elastic design, the elasto-plastic layer displacement check calculation is also required. Therefore, we should try our best to make the structural layout meet the regularity requirements.
Overall, the important role of Residential steel building in our daily lives is perceived by more and more people. Qingdao Xinguangzheng Steel Structure Co., Ltd. strives to offer high quality Residential steel building at reasonable prices, efficient production times and the most professional customer service.
Qingdao Activa Group is the largest outdoor leisure products R & D and production enterprise in the world. It has established factories and branches in 14 countries and regions. Currently, it has five hundred year brands in its industry, and 1820 patents at home and abroad. The first phase project of Qingdao Activa Group, which is contracted by our company, has a total construction area of over 80000, which is the general contracting project.
The development of residential steel building conforms to the industrial technology policy of protecting arable land and saving energy, and is also one of the production methods for realizing residential industrialization. The development of steel structure housing is the general trend.
What is the layout of the residential steel building?
What issues should be paid attention to when designing residential steel building?
Why pay attention to the design of residential steel building?
residential steel building’s column grid layout should be regular, and it is advisable to use residential units or sleeves as the unit to achieve modularity. The modular flat connection, wrong connection and symmetrical concave (convex) connection and other splicing adapt to changes in the overall layout .
When the residential steel building module adopts small column net, it should be combined with the floor and pipeline design; when the module adopts large column net, the facility pipeline should be designed as a fixed-positioned tube bundle, and the electrical and communication lines can be along the cavity and skirting of the partition wall. , Mirror hanging line or top line arrangement.
The kitchen and bathroom are located close to the concrete core tube or concrete shear wall, and avoid steel structure load-bearing components to facilitate the fire prevention and anti-corrosion treatment of steel components.
Vertical pipelines are centrally arranged in pipeline wells or pipeline walls, or installed on site using factory prefabricated tube bundles.
The toilet is drained on the same floor. Use a double pipe system for centralized heating, and use a temperature control valve and a heat meter. Use the equipotential characteristics of the steel structure to make a natural ground connection.
residential steel building should be dominated by construction and design, and other professions should interact closely with each other. In addition to following the general principles of residential building design, residential steel building must also focus on solving:
(1) How to make use of the advantages of steel structure? The beam span can be enlarged, the bays can be more flexible, and more space can be created for residents. But how to avoid the flatness and monotonous facade of the building caused by the steel structure.
(2) It is necessary to solve the fire protection and anti-corrosion problems of steel structure residential buildings. Especially in rainy areas, the quality of anti-corrosion and anti-rust work directly affects the promotion of steel structure housing.
The cost of residential steel building is the most concerned issue of real estate developers. Steel structure residences should be positioned in middle and high-end residences. Steel structure residences are a systematic project. Management and coordination should be strengthened from design, manufacturing, transportation, installation, maintenance and management, so as to reduce costs and improve overall economic benefits. the goal of.
Qingdao Xinguangzheng Steel Structure Co., Ltd. strives to provide top-quality residential steel buildings with reasonable prices, efficient production time, and the most professional customer service.
Prefab House only prefabricates some parts, and it must be poured in the same way as traditional buildings on the construction site. It is not "building blocks" as imagined. Therefore, no difference can be seen from the appearance of the house after it is built. Here we are going to introduce the Prefab House.
What are the reasons why people choose Prefab House?
What are the advantages of steel structure prefabricated houses?
What are the advantages of Prefab House for building plant?
1. Prefab House is of great benefit to energy conservation and environmental protection. Through factory production and on-site assembly construction, it can greatly reduce construction waste and construction sewage, reduce construction noise, reduce harmful gas and dust emissions, and reduce on-site construction and management personnel. Generally, it can save 20% of materials and about 60% of water.
2. The housing industrialization of Prefab House is not only beneficial to the capital flow of development enterprises, but can also increase the speed of housing listing, so it can greatly alleviate the current situation of insufficient market supply and adjust the supply relationship. After large-scale promotion, construction costs can be reduced, and it will also play a role in restraining housing prices.
3. Comprehensive cost accounting shows that the construction cost of Prefab House is higher than that of traditional construction methods, but after large-scale promotion, construction costs can be reduced.
First, the components of prefabricated houses can be industrialized in factories. The components are equivalent to standard products and can be installed directly after being transported to the site. It can be said to be convenient and fast. The construction field during the construction period, especially the unparalleled advantages.
prefabricated houses with steel structure are more stable than those made of welded frame steel. In addition, it is cheaper and more economical. Long service life, 50-70 years. Locked with bolts, it can be used repeatedly without any maintenance.
1. Large span: such Prefab House can realize single span or multi span, and the maximum span without center column is 36m.
2. Low cost: according to the requirements of customers, the unit price of Prefab House ranges from $150 / m2 to $300 / m2.
3. Convenient installation and short construction time: save manpower and cost for customers.
4. Prefab House has a long service life: up to 50 years
5. Environmental protection: such buildings are free of harmful substances.
6. Structural stability: earthquake resistance, wind resistance and snow resistance.
7. Others such as waterproof, heat insulation and energy saving.
The Prefab House produced by Qingdao Xinguangzheng Steel Structure Co., Ltd. has been exported to several countries. And there are several offices in the country, which is convenient for domestic customers to maintain. Based on technological innovation, their company constantly improves product quality and provides you with professional Prefab House.
Ⅰ. Steel column installation for steel structure construction
1. Installation sequence of steel column:
① Foundation setting out → ② binding → ③ hoisting → ④ correction → ⑤ final fixation
2. Installation method of steel column:
(1) Setting out:
A. Elevation control:
In this structural steel construction project, iron parts and "middle bars" are controlled according to the depth of concrete cup mouth, the elevation of steel column bottom and the embedded elevation in the center of the bottom of the cup mouth during the construction of concrete foundation (φ30 steel bars), the elevation of top surface of "middle reinforcement" is based on the elevation of steel column bottom, and the elevation error of iron parts is controlled in ± Within 1mm.
To ensure the steel column is embedded in the foundation accurately and firmly φ On the 30 "middle reinforcement", weld a steel plate with thickness of 20 at the bottom of H-shaped steel column, as shown in the figure below.
When installing structural steel column, clean the foundation cup mouth first, and check the embedded elevation control "middle reinforcement" in the foundation（φ The actual height of 30 steel bars) is not necessary because the elevation embedded in the foundation construction has been controlled precisely, and no additional iron pad is needed. The method is simple, fast and efficient for the treatment of steel column feet. The construction is fast and the force is reasonable. When the column is lifted, it can be adjusted freely in several directions when the elevation is unchanged.
B. Before installation, the vertical and horizontal axis reference lines of the foundation plane shall be placed on the top of the cup mouth by woodworking ink bucket as the installation and positioning line of steel column.
(2) Column binding and hoisting:
A. after the steel column enters the site, the steel column shall be arranged according to the position of the lifting plan, and the model and number shall be checked to see if they are correct. The plane position of steel column after entering the site is shown in the following figure.
B. Before the column is lifted, a horizontal line shall be drawn with red oil paint 2300mm upward from the bottom of the column, so as to recheck the plane elevation datum before and after the installation and fixation.
C. the column installation belongs to vertical hoisting. In order to keep the suspended column drooping and facilitate the positioning, the binding point is determined at the lower part of the bracket. In order to prevent the sharp edges and corners of the column edge from damaging the lifting rope during hoisting, the rubber belt of the old car is used to separate and cover the edge and corner lifting rope. Pay attention to binding firmly and easy to remove.
D. temporary steel ladder and high-strength bolt installation fixture of working platform shall be bound on the steel column.
E. in order to avoid the free swing of the suspended column, hemp rope should be used to tie the upper part of the column bottom as a restraint rope and adjust the direction.
F. according to the site conditions, the rotation method is adopted for hoisting
After the preparations before hoisting are ready, the trial hoisting shall be carried out first. When the height of the steel column is 200 mm above the ground, the hoisting shall be stopped to check whether the rigging is firm and whether the crane is stable. After confirming that there is no problem, the crane can be directed to slowly lift, rotate to the top of the cup mouth, and then slowly descend. When the distance between the bottom of the column and the design position is 40-100 mm, adjust the two datum lines of the column body and the foundation to reach the accurate position, direct the crane to descend to the position, and temporarily fix the column with steel wedge (or wood wedge) and wind rope to remove the hook.
• Key points of rotation method:
The method of lifting the column by rotating the column around the column base is called rotation method, as shown in figure a below. When the column is hoisted by rotation method, in order to improve the hoisting efficiency, when the steel column enters the site, the binding point of the column, the center of the column base and the center of the cup foundation should be placed on the arc with the crane stop point as the center and the distance from the stop point to the binding point (i.e. the turning radius of the column), as shown in Figure B below.
The steel column hoisting is shown in the figure below:
(3) Preliminary correction of column:
The column should be corrected on the side with large deviation first, and then on the side with small deviation.
A. The correction of column generally includes plane position, elevation and perpendicularity.
B. When the steel column is hoisted in place, it is one-time alignment, and generally it does not need plane re correction. For the elevation of the column, it has been used before hoisting φ The embedded "middle reinforcement" can accurately control the elevation. Generally, it only needs to be checked, and it does not need to be corrected. Therefore, the steel column correction is mainly to correct the verticality and recheck the elevation.
C. In this project, the perpendicularity of the column is observed, and two theodolites are used for measurement and correction.
• First, place the theodolite on one side of the column, align the longitudinal center wire with the baseline of the column base, and then fix the screws of the horizontal plate.
• Measure the center line of the column and observe from bottom to top. If the vertical center line is aligned, that is, the column is vertical. If it is not aligned, the column shall be adjusted until it is aligned with the longitudinal center line of theodolite.
• Measure the horizontal line in the same way so that the center line of the other side of the column is perpendicular to the horizontal axis of the baseline. After the column is accurately positioned, the column can be fixed.
• Verticality correction of steel column: distance adjusting screw rod and steel wedge are used. Due to the small contact surface of the long side of the column, the base plate is set during the construction. The details are as follows.
The manufacturing dimension of steel wedge is shown in the figure below:
(4) Final alignment and fixation of steel columns:
After the steel column is hoisted in place, the column correction mainly involves the adjustment of elevation and the correction of verticality; The correction method can use tools such as wind rope, Jack, crowbar and steel wedge (or wooden wedge) to apply vertical force and lateral force of pulling, jacking, supporting and prying to the steel column.
Adjust the verticality, positioning axis and elevation of the column. After confirming the correctness, the gap between the steel column and the foundation cup mouth shall be poured with C40 fine stone concrete. The expansive high strength grouting material is preferred.
Ⅱ Protection of site components:
1) The unloading of components shall be careful to prevent damage and prevent collision and extrusion between members.
2) The members shall be stacked in order at the designated site, and the number of layers stacked by steel beams shall not exceed 3 layers to prevent the members from squeezing and deformation.
3) Before hoisting, oil, sediment and dust on the surface of the components shall be cleaned.
Ⅲ The placement of components and the requirements for the site
1) When unloading, the components are unloaded directly near the installation position and within the radius of rotation of the crane. Mark the number clearly with a clear color pen to facilitate lifting.
2) The components are placed in order in the site, and a certain gap is reserved between adjacent components to facilitate binding.
3) The site shall be solid and flat, and the components shall not be polluted due to rain and snow, and the vehicle with 30 ton level can be walked.
Ⅳ Steel structure building installation
Preparation before hoisting of steel column:
Before hoisting the steel column, the cable wind rope shall be tied to the column body. The lifting point shall be at the bracket position, and the double wire rope shall be set up and down, and the snap ring can be checked to be qualified before entering the next work. Before hoisting the steel column, the positioning axis, foundation axis and elevation, cup opening size and the height of the bottom standard of the steel column must be inspected and handed over and accepted. The number, outline dimension, screw hole position and diameter of the steel column shall be comprehensively reviewed. After confirming that it meets the requirements of design drawings, draw out the installation center line and the lower end elevation line of the steel column.
Ⅴ Steel column hoisting
(1) installation method of steel column
Before lifting the steel column, the wooden board shall be fixed at the column foot to prevent damage to the column foot and other structures.
Special hoisting steel wire rope is used for steel column binding. Wood or rubber sheet shall be used to prevent damage to the steel column.
The steel column is installed by a 25t truck crane. When the steel column is lifted, the crane shall hook and rotate the arm while lifting the steel column to make the steel column vertical away from the ground.
(2) positioning adjustment and temporary fixation
When the steel column is lifted to 200mm above the base cup mouth, it will be stable, and it will fall slowly at the base cup mouth. Avoid hitting the concrete edge of the foundation cup mouth during falling. After implementation, use special angle ruler to check, adjust the steel column to make its positioning line coincide with the foundation positioning axis. Three people are required to operate the adjustment, one person moves the steel column, one person helps to stabilize and the other person conducts the test. The positioning error is controlled within 2mm.
(3) when adjusting the elevation of the steel column, place the pad iron at the bottom of the cup foundation, use the level to super level the bottom plate elevation of the steel column as the top elevation of the pad iron, so that the elevation after the steel column is in place can meet the design elevation requirements, mark the elevation datum point on the column body, and then use the level to measure the installation elevation after it is installed in place.
(4) the verticality of the steel column shall be preliminary adjusted by the level ruler. Then two theodolites are used to observe from both sides of the column at the same time, and the adjustment is carried out by relying on the cable wind rope. As shown in the figure below:
Diagram of verticality adjustment of steel column
(5) after the adjustment, use eight iron wedges to position the gap between the bottom of the steel column and the base of the cup mouth, and then spot weld the column to make it stable.
Ⅵ Steel beam installation
Steel beams must be stacked in order on site for this steel work in construction. Sleepers must be placed in the middle of each layer of steel beams. Two lifting points for steel beam hoisting are selected on both sides of the center of gravity of the steel beam. The two lifting points should be 800mm away from the support and the middle of the span, and the distance between the two lifting points should be increased according to the length of the steel beam.
To ensure safety and prevent the sharp edge of the steel beam from cutting the steel wire rope, the steel wire rope shall be protected, the angle of the sling shall not be less than 450, and the steel beam shall be directly tied and rolled with the steel wire rope or lifted with a special fixture.
Before hoisting the steel beam, install the safety rope on the steel beam. When hoisting, hang two sliding ropes at both ends of the steel beam. Two people pull two sliding ropes respectively. The hoisting speed of the steel beam must be slow. In order to ensure safety, personnel should not stand directly under the beam. The cloth bags specially used for placing high-strength bolts are put on both ends of the steel beam. When the steel beam is hoisted above the position, the steel beam is put in place. The falling speed of the steel beam is controlled at 3m / min. two installers are arranged at both ends of the steel column head to prepare for the installation of the steel beam. When the steel beam is close to the in place position, two installers should hold the upper flange of the steel beam with their hands respectively, drag the steel beam to the in place position, and prepare to install the high-strength bolts.
Ⅶ Installation of retaining structure and support corner brace
1) Installation of roof purlin: when the main structural steel forms a frame section, the roof purlin is hoisted to the main beam of the roof with a crane and installed manually. The purlin can also be manually pulled onto the roof with a white synthetic rope for installation. After the installation of purlin, the purlin support is installed in time.
2) Wall purlin installation: when the main structure forms a frame section, the construction personnel stand on the scaffold platform and pull the wall purlin to the installation position with white comprehensive rope.
3) Corner brace installation: after the main body is welded, the corner brace is connected.
Ⅷ Measurement and correction of steel column
Verticality correction of steel column
When the steel column is installed and corrected, two theodolites are set up on the control line with 90 degree translation of 1 meter each other, and the theodolite operators observe the small steel ruler on the top of the column, measure the deviation of the steel column and direct the correction.
A. Control the verticality of the steel column between the first hoisting joints.
B. Steel column calibration is divided into four steps:
initial calibration during initial tightening; Re-calibration before final tightening; Tracking and monitoring during welding process; Final result measurement after welding.
The perpendicularity can be roughly controlled with a long level before the initial tightening, and it can be accurately corrected after the frame is formed. After welding, retest shall be carried out, and the measurement results shall be compared with those at final tightening, so as to be the basis for the next construction.
C. Verticality measurement method of C steel column
Initial correction: the perpendicularity of the steel column is preliminary adjusted with a level ruler.
Accurate correction of steel column perpendicularity: one column grid is used as an installation section for the hoisting of the main frame until the hoisting of three continuous complete sections is completed
After the whole is formed, the measurement correction can be inserted. Two theodolites are used to observe from both sides of the column at the same time, and the wind rope is used for correction and adjustment.
Ⅸ Steel structure survey
2) Elevation control of steel column
Based on the elevation reference point of the plane layer where the steel column is located, the deviation value of the horizontal elevation of the steel column is measured with the level gauge and the correction is directed.
3) Steel beam measurement
After the steel column is hoisted and corrected, the +1.00m control point shall be measured to each steel column according to the site level as the basis for vertical transfer of elevation and the elevation of beam installation; Pop up the center line of the steel beam on the surface of the steel beam.
The control axis is measured to the column body to control the beam position offset; The accuracy of beam elevation is controlled according to the control point of column elevation. Set up theodolite on the floor platform, and then look at the cross angle to the axis of the corresponding beam. Aim at the center line of the upper surface of the beam to the other end with theodolite to see if the number coincides with the axis of the beam.
Calculation of survey and lofting data
In this project, the computer automatic query method is used to calculate the survey and lofting data. The specific steps are as follows:
1) The establishment of data model
Firstly, according to the design coordinates and the dimension relationship of each building in the design drawing, the building, building axis, control line to be lofted and so on are drawn in AutoCAD according to the proportion, and the data model is established.
2) Survey and lofting data query
After drawing the survey loft data model, the survey loft data such as the angle and distance between the known basis (axis control pile, lofted axis, etc.) and the control line to be lofted are queried by using the command of dist of AutoCAD.
3) Advantages of computer automatic query
The method of computer automatic query is used to obtain the required measurement and positioning data. It is not only convenient to calculate, but also has high precision. The distance precision can be set to 0.1mm, 0.01mm, and the angle precision to 0.0 ", 0.00" or higher according to the actual situation.
Ⅹ Construction of high strength bolt
1. Preparation before installation
1) Test and inspection of high strength bolt
Anti slip coefficient test
The project adopts class 10.9 large hexagon high-strength bolts. The anti slip coefficient test of high-strength bolts shall be conducted by taking the most representative thickness of the plate in the project for test, and three groups shall be made.
The size of the specimen plate is as follows:
Axial force test
Randomly select the bolts to be installed at the construction site, and 8 sets of bolt pairs are selected for re inspection in each batch.
2) Transportation and storage of high strength bolts
The form, size and technical conditions of high-strength bolt connecting pair shall be manufactured and supplied by the manufacturer according to batch, with factory certificate and high-strength bolt connection pair, which shall conform to the provisions of national standards gb1228-1231-84 and gb3632-3633-83. High strength bolts with large hexagon for steel structure
The connecting pair consists of a bolt, a nut and two washers. The combination of use shall meet the national standards, and the high-strength bolt connection pair shall be supplied with storage and transportation in the same batch.
The high-strength bolt connecting pair shall be installed and placed lightly during loading, unloading, transportation and storage to prevent the packing box from being damaged or damaged.
Storage of high strength bolt warehouse
1. the high-strength bolt connection pair shall be cleaned according to the specification, batch number and supply date of the packing box, and shall be kept in the indoor warehouse, and the accumulation shall not be higher than 3 layers. The indoor moisture-proof, long-term dry, rust and dirt contamination shall be prevented, and torque coefficient shall be prevented from changing. The bottom layer shall be more than 300mm above the ground level.
2. when installing on site, the quantity of high-strength bolts required on the day shall be issued. The rest should be kept properly. Do not put it in disorder, damage the thread, and be contaminated with dirt.
3. before using the long-term storage high-strength bolt connection pair, a comprehensive quality inspection shall be conducted again. If any abnormal phenomenon is found after unpacking, the inspection standard shall be conducted according to the relevant provisions of national standards gb1228-1231-84 and gb3632-3633-83. It can be used after being qualified.
3) Construction management of high strength bolts
1. Construction Manager
When carrying out the construction of this high-strength bolt, the high-strength bolt manager shall be determined first to be responsible for the project management, quality management and guidance of the construction personnel.
2. weather management (climate conditions)
In principle, no operation shall be carried out during rainfall and snowfall. If rain or snow fall occurs during operation, the speed shall be accelerated to lock the unfinished ones
3. friction surface management
Before tightening, the friction surface shall be inspected first. If there are any attachments to reduce bearing capacity of friction surface, such as rust, oil, paint and residue, metal brush, sandpaper and oxygen acetylene flame shall be used for removal.
4) Construction of high strength bolts
1. final tightening of temporary bolts
Before inserting high-strength bolts, temporary bolts shall be used to tighten the connection tightly, if the materials of the connection parts are bent or warped, they shall be corrected.
If the difference of holes is within 2mm, it can be corrected by cutter.
If the difference of holes exceeds 2mm, reasonable treatment methods such as replacement of panel shall be adopted based on consultation with management personnel, and gas cutting and reaming are not allowed.
2. high strength bolt insertion
The nut and gasket of high-strength bolt shall pay attention to the installation direction, and install according to the following figure.
When inserting bolts, pay attention not to attach rust, dust, oil, etc. to the bolts. In addition, do not force into the bolt hole during construction to avoid damaging the thread.
3. initial tightening
After the temporary fixing bolts are locked, confirm the compactness of the components.
After initial tightening, mark with white marker through bolt nut, gasket and component.
When using the inspection wrench, although the torque value can be confirmed by the contact sound, it is easy to over tighten if the mechanism continues to apply force, so it should be noted.
4) Final tightening
After initial tightening, use special fastening wrench to lock until the neck is broken.
In principle, the bolts inserted on the same day shall be screwed out on the same day.