First, the general situation and characteristics of the project.
1) Overview of the project.
1. Construction unit: north**.
2. Design unit: **
3. Project management company: **
4. Supervision unit: **
5. Construction unit: **
6. Project construction area, height and structure type:
7. Foundation form: pile foundation + raft plate.
8. Floor area:
9. Total amount of steel:
10. Project nature: office + hotel (commercial).
11. Project address: southwest corner of Guomao Bridge, Jianguomenwai Street, Chaocheng District, Beijing.
2) Project characteristics.
1. The four underground floors of the hotel tower are steel-reinforced concrete frame shear structures, the inner cylinder of the 62 floors above ground is a steel structure, the outer cylinder is an all-steel structure, and the floor slab is a profiled steel plate-concrete composite floor slab. The 3 floors of the office building and below are reinforced concrete frame shear structures, the columns on the ground are steel concrete, the floor beams between the 5 floors and above are steel beams, and the floor slabs are profiled steel plates-concrete composite floor slabs. The inner tube structure is a reinforced concrete shear wall.
2. The steel used in this project:
1) Q345GJZ-C: beams and conversion members used for connecting steel columns, support rods, outrigger truss rods and damping supports. The thickness of the plate is t, 40 t 60mm is Z15, and t is greater than 60mm is Z25.
2) Q345GJZ-D: steel columns, steel beams and structural components connected with lanterns for lanterns.
3) Q345GJZ-C: used for the main beam and secondary beam of each floor.
4）q345gjb
3. Steel columns: 1) Underground part:
The inner cylinder of the hotel tower: box-shaped steel columns, welded HH-shaped steel columns, plate thickness 40 100mm.
The outer cylinder of the hotel tower: box-shaped steel columns, cross-shaped steel columns, with a plate thickness of 20 100mm.
East and West Office Building Inner Tube:
Outer cylinder of the east and west office buildings: cross-shaped steel columns, (from B2) plate thickness 50mm.
2) Above-ground parts:
4. Steel beam: 1) Underground part:
Hotel tower outer tube skirt beam: plate thickness 16 40mm.
Inner skirt beam of the hotel tower: plate thickness 10 65mm.
2) Above-ground parts:
Plate thickness: steel beam 20 100mm.
5. Most of the steel component connection methods are bolt welded connections, and in the construction of column and beam, beam and beam connection, the sequence is the first initial screwing of the composite plate high-strength bolt connection, and the final screwing of the flange weld of the welded beam.
6. Difficulties of this project:
1) High building height: high accuracy in the production and installation of steel components is required.
2) Difficulty in welding thick plates: steel components are required to strengthen the management and monitoring of welding in the process of production and installation, control all factors that produce cold cracks in welding, and adopt a reasonable welding sequence to avoid welding deformation.
Second, the basis for compilation.
a) Contracts. 1. General contract for the construction of Beijing Silver Pump Center.
2. Beijing Silver Pump Center Construction Project Construction Subcontract.
3. Beijing Silver Pump Center Construction Project Entrusted Supervision Contract.
b) Miscellaneous. 1. Regulations for the Supervision of Construction Projects (DBJ01-41-2002).
2. Construction drawings and design descriptions of the steel structure design of the project.
3. The project has been approved by the supervision planning and construction organization design.
4. Code for acceptance of construction quality of steel structure engineering (GB50205-2001).
Third, the quality control of steel structure engineering.
1) Quality control in the construction preparation stage.
1. The main content of steel structure production and installation quality control.
1) Review of engineering and technical documents:
1) Familiar with relevant technical documents;
2) Familiar with the review of construction drawings;
3) Check the compliance of the detailed design and processing drawings with the construction drawings (resident supervisors);
4) Review the various processes (processing schemes) of the processing of components in the steel structure processing plant;
5) Review the construction organization design (construction plan) of on-site installation.
2) Review the contractor's quality management system and quality assurance measures:
1) The establishment of the organizational structure and the implementation of the division of responsibilities of personnel;
2) management personnel and operators holding certificates, the technical person in charge should have intermediate or above professional titles, professional quality inspectors should have quality inspector certificates, welders in addition to the certificate, should also have the qualification certificate of the additional examination of the welder of the project, non-destructive testing personnel above the second level of qualification, surveyors should have intermediate titles or above (installation unit), preheating, post-heating and gas cutting personnel should have the on-the-job operation certificate;
3) It should have a sound quality management system.
3) Review and inspect engineering materials
1) Steel;2) Welding materials;
3) High-strength bolt connection pair;
4) Profiled steel plates, coating materials, etc.
4) Additional examination and process test for welders:
1) Review the welder additional examination plan, and supervise the implementation, the implementation of the side station;
2) Review the welding process qualification plan and supervise the implementation;
3) Review the re-inspection plan of high-strength bolt connection and supervise the implementation, and implement the side station;
4) Review the anti-slip coefficient inspection (re)inspection plan of the friction surface of high-strength bolt connection, and supervise the implementation, and implement the side station.
5) Review the qualifications of suppliers and laboratories;
1) Business licenses and qualifications of steel, welding consumables, high-strength bolt joints, profiled steel plates and coating materials, etc
2) Laboratory qualifications related to the above tests and re-testing of engineering materials.
6) Review the equipment readiness of the contractor:
1) The construction equipment is in good condition to have a certificate;
2) All kinds of experimental and inspection instruments are in good condition, and the inspection must be within the validity period
3) The measuring instruments are qualified and within the validity period, the accuracy of the measuring instruments used by the component processing, installation, quality inspection and project supervision department has been passed, and the error is in accordance with the regulations
4) The process equipment has been fully configured according to the contract, and is in good condition, with qualified spots.
7) Others: 1) The preparation of the production and installation schedule has been completed, and has been approved by the project supervision department and the construction unit
2) The safety production management system and safety production measures have been compiled, and the institutions and personnel have been put in place
3) The production and installation of sub-divisions of the sub-project inspection batch has been clarified, the quality inspection method and form have been clarified, and the supervision review and approval.
After the completion of the above work, the construction unit fills in the "construction site quality management inspection record", and after the supervision inspection and approval, fill in the "steel structure production (installation) project construction application form" to apply for starting, and the project supervision department and the construction unit review and consent before starting construction.
2. Quality control of several important links.
1) Quality control of several important engineering materials.
1) Steel: The contractor shall provide the following information to the project supervision department as the basis for steel quality control:
a. Steel production and inspection standards in the steel supply contract
b. Supply steel mill business license, qualification and other information.
Review the quality certificate of the steel mill and inspect all of them
Review of steel re-inspection plans and schemes:
a. In the following cases, the steel should be sampled for re-inspection:
a. Imported steel from abroad;
b. Mixed batches of steel;
c. The thickness of the plate is 40mm, and the thick plate is designed with Z-direction performance requirements
d. The safety level of the building structure is a level, and the steel used in the main stressed components of the long-span steel structure;
e. The design has the steel requirements for re-inspection;
f. Steel with doubts about quality.
b. Re-inspection items:
According to the requirements of the technical conditions in the steel order contract, the current national standards, the design requirements of the project or the construction, design, supervision and other requirements of the contractor and other mutually agreed projects.
In general, the following items should be included:
a. Tensile test of steel, test yield strength, tensile strength and elongation, and calculate yield strength;
b. Impact toughness of steel (20,0,-20) test;
C, Z-direction performance (Z15, Z25, Z35);
D. Chemical composition analysis: C, Mn, Si, P, S In addition to the above five elements, some should add Cr, Ni, Cu, V, Nb, Ti, Mo, Al and other elements, and calculate CEQ (%
e. Full inspection: non-metallic slag inclusions, ferrite grain size;
f. Ultrasonic inspection.
C. Requirements: a. Before the steel re-inspection, the contractor shall prepare the steel re-inspection plan, determine the re-inspection project, the proportion of spot checks, etc., and submit it to the design, supervision and construction unit for review and confirmation, (agreed at the meeting).
b. After the retest, the contractor shall submit the retest report to the project supervision department for review and approval.
c. The contractor submits the qualification of the steel retest experimental unit in advance to the project supervision department for review.
d. Review the steel management system of the contractor, and check the management, storage, distribution, use, quality and traceability measures of the steel.
e. Check the batch number and steel number of the furnace according to the quality certificate for the steel that is fully qualified for the quality certification documents, and check the thickness of the steel plate and the specifications and sizes of the section steel according to each variety, with the same specification 5 places, and check the appearance quality, pitting and end edges.
2) Welding consumables (including welding rods, welding wires, fluxes, shielding gases, welding nozzles for melt resistance electroslag welding, etc.):
The contractor shall provide the following information to the project supervision department:
a. The relevant production and inspection standards in the order contract;
b. Business license, qualification and other information of the welding consumables production unit.
Inspect the quality certificate of welding consumables and check all of them.
Review the re-inspection plan and scheme of welding consumables:
a. The number of re-inspection shall be approved or the number of random inspections shall be jointly agreed upon by the construction, design, supervision and contracting units;
b. The re-inspection project shall be in accordance with the requirements of the technical conditions in the order contract, corresponding to the current national standards, the design requirements of the project or the project agreed upon by the construction, design, supervision and contracting unit.
Review the qualifications of the welding consumables re-inspection laboratory.
Review the welding consumables management system of the contractor, check the management, storage, distribution, use and quality of materials, and check the baking records and baking conditions of welding consumables.
The quality certification documents are qualified to enter the welding consumables spot check, the welding rod should not have defects such as peeling off the coating, rusting of the welding core, the flux should not be damp and agglomerating, and the specifications and deviations of the welding nails and welding porcelain rings should comply with the provisions of GB10433
a. Welding nails: 16 035、ф19±0.42、ф22±0.42；
b. Porcelain ring: The dimensional tolerance of the porcelain ring should be able to ensure the interchangeability of welding nails of the same specification.
Random inspection is 1% of the quantity, and not less than 10 packages (sets).
If there is a quality problem after unpacking (bag) that has not been spot-checked, it cannot be used to clear the site.
3) High-strength bolt connection pair;
a. The production and inspection standards of high-strength bolt joints in the order contract;
b. Business license, qualification and other information of high-strength bolt connection sub-production unit.
High-strength bolted joints (bolts, nuts, washers) should be supplied in boxes, and the factory certificate, quality certificate and quality inspection report should be inspected. Large hexagonal head high-strength bolt connection pair, focusing on the inspection of torque coefficient inspection report;Torsional shear high-strength bolt connection pair, focusing on the inspection report of fastening axial force.
Review the qualification of the re-inspection test unit of high-strength bolt joints.
Review the re-inspection plan and plan of high-strength bolted joints.
We review the storage system of high-strength bolted joints.
The quality certification documents are qualified to enter the high-strength bolt connection pair according to the packing box spot check 5%, and 3 boxes, should not appear rusty, dirty, threads should not be damaged, the surface is oiled protection.
4) Profiled metal plate:
Review the business license, qualification and other information of the profiled steel plate production unit.
All quality certification documents, Chinese marks and inspection reports should be inspected, and should meet the design requirements.
The specification size and allowable deviation of the profiled metal plate, the surface quality should meet the design requirements, 5% of each random inspection, and 3 pieces.
5. Coating materials:
Review the business license, qualification, production license and other materials of the coating material production unit.
The contractor shall provide the relevant technical conditions and production and inspection standards in the order contract.
Review the variety, specification and performance of anticorrosive coatings, thinners and curing agents and other materials in line with the current national product standards and design requirements. All quality certificates and inspection reports are inspected.
Review the varieties and technical properties of fireproof coatings to meet the design requirements, and should be tested by qualified testing units, meet the specifications of current national standards, and fully check quality certification documents, Chinese marks, inspection reports and type approval and other information.
Check that the physical object is consistent with the quality certification documents within the validity period, and 5% of the barrels shall be randomly inspected, and there shall be no less than 3 barrels, and there shall be no crusts, agglomerations, gels, etc.
6) Anchor bolts:
Anchor bolts should generally be processed by the steel component manufacturer or installation unit, in addition to which the business license and qualification of the processing unit should be reviewed.
When the anchor bolt burial construction unit fills in the "Engineering Materials Entry Inspection Form", it should have effective drawings for the processing of anchor bolts, steel quality certificates, steel re-inspection reports and hand-copies of materials, factory certificates and self-inspection records. The project supervision department will conduct spot checks on Anhui specifications.
2) Welder qualification review.
1) Before the contractor declares the construction organization design (at the latest at the same time), the list of welders participating in the construction of the project and the projects that meet the requirements of the project, the valid welder certificate and the approval documents of the welder examination committee shall be submitted to the project supervision department for verification.
Verify the seal and approval documents of the issuing unit of the welder's certificate of conformity;
Review whether the qualified items of the welder certificate meet the requirements of this project and JGJ81-2002;
Check whether the relevant qualification items of the welder's certificate are within the validity period.
2) Review and test the qualifications of the test board experimental unit for the welder examination.
3) Review the contractor's declaration of the "Welder Additional Examination Plan and Program":
The list of welders who participate in the additional examination and attach the qualification certificate with the basic skills of the corresponding project, all welders who participate in the construction of the project participate in the examination;
The content of the additional examination should meet the requirements of the project, the welding method selected is used in the construction, and the selected node form and welding position are representative in the project
Welding process instruction;
The inspection items, methods and qualification standards shall conform to JBJ81-2002 No. 94.Article 3;
Schedule and organization.
4) The project supervision department should send supervisors to stand next to the welder additional examination process and supervise.
5) According to the welder certificate submitted by the contractor and the certificate of passing the additional examination, the project supervision department confirms the welders who participate in the construction of the project.
Note: Welders include manual welders and automatic operation welders. Among them, manual welders include manual welders of welding rods, automatic CO2 gas shielded welders and positioning manual welders, and automatic operation welders include automatic submerged arc welders, electroslag welders and bolt welders. Only manual welders (excluding positioning welders) are required for the additional examination of welders, and the rest can have corresponding valid welder certificates.
3) Welding process qualification.
The qualified result of welding process qualification is the basis for the formulation of welding process documents. The steel structure production and installation unit is required to carry out welding process evaluation according to the steel, welding materials, welding methods, welding positions, nodes and grooves selected in the engineering design drawings before welding construction.
1) Review the existing welding process qualification report declared by the contractor to be used in this project.
2) Review the welding process qualification plan and plan that need to be supplemented by the contractor.
According to the construction drawings or steel component processing details, according to the requirements of JGJ81-2002;
Welding method, the steel components of this project are made by manual welding of welding rods, semi-automatic CO2 gas shielded welding, automatic submerged arc welding, fused electroslag welding (or non-dissolving nozzle electroslag welding) and non-penetrating bolt welding. The steel structure is installed by manual welding of welding rods, semi-automatic CO2 gas shielded welding, and penetrating nail welding
Steel, this project with Q345B, Q345GJ-C, Q345GJ-D, Q345GJZ15-C, Q345GJZ25-C, according to the steel quality grade and Z-direction performance requirements are selected, the test plate is inspected and re-inspected according to the requirements of the material
Joint form and welding position, steel component production, there are cross-shaped joints, T-joints, corner joints and butt joints, except for the electroslag welding vertical welding position, are flat;
The thickness of the steel plate is 20 100mm, and the entire project should be covered according to various types of joints and other conditions
After the welding consumables are selected, they will be inspected and re-inspected according to the requirements of the materials
The size of the groove shall be reviewed according to the fourth chapter of JGJ81-2002.
The combination of the above conditions must cover the entire project node.
Due to the existence of part of the project while the construction side of the design, so the welding process assessment is difficult to be in place before the start of the project, after the follow-up construction drawings are sent down, pay attention to the node form and plate thickness, the welding process assessment that has been done before can not cover the nodes in the follow-up drawings, and must be supplemented immediately to avoid missing items.
Review the welding process instructions for each assessment item;
Review the inspection items of each assessment item and the standards for the implementation of the test method;
Review the welding process qualification schedule and organization.
3) Review and inspect the experimental qualifications of welding process evaluation samples.
4) The project supervision department of the welding process qualification process sends supervision personnel to supervise the implementation of the program.
5) Witness sampling and sample delivery test:
The blanking and numbering of the welding test plate should be consistent with the welding process instruction;
Processing of specimens, transplantation of specimen numbers, marking and saving of specimen remnants;
The specimen is witnessed and sent to the laboratory and the test process is stationed.
The contractor fills in the "Engineering and Technical Document Application Form" to declare the welding process assessment report, and the supervision and review it is signed.
4) Inspection (re)inspection and review of anti-slip coefficient of friction surface of high-strength bolt connection.
1) Review the qualification of anti-slip coefficient test of friction surface.
2) Review the anti-slip coefficient test scheme and plan of the friction surface
According to the steel structure production batch for the unit of anti-slip coefficient test, 2000t for a batch, less than 2000t as a batch, according to this provision according to the project layer by layer steel converted into a batch of columns. Less than 2000t below plus or minus zero can be counted according to the eye batch;
The steel structure fabrication plant and the installation unit are inspected and re-inspected in batches respectively
The anti-slip coefficient test specimen and its representative steel components should be the same material, the same friction surface treatment process, each batch of factory processing six groups, three of which by the factory commissioned inspection, the other three groups by the installation unit commissioned by the re-inspection;
The requirements, dimensions and test methods of the friction surface between the specimen and the representative component shall be in accordance with Appendix B. of GB502050.Provisions of 5:
Schedule. 3) The anti-slip coefficient test and re-inspection of the friction surface shall be supervised by the side station.
2) Quality control of the construction process.
According to the provisions of the Code for Acceptance of Construction Quality of Steel Structure Engineering (GB50205-2001), in the construction process, in addition to controlling the quality according to the inspection batch of each sub-project, some items in the inspection batch of some sub-projects involving structural safety and life and related technical documents, personnel and equipment should be strictly controlled in the process of steel structure production and installation.
1. Steel component production.
1) Review of engineering and technical documents:
1) Welding H-shaped steel, cross-shaped steel, box-shaped and other more complex component assembly process;
2) Welding process of H-shaped steel, cross-shaped steel, box-shaped and other components;
3) Deformation correction process instruction for parts and components;
4) Pre-spelling scheme;
5) Anti-corrosion coating process instruction.
2) Check the technical quality management measures of the steel component manufacturing plant
1) Quality assurance system;
2) The construction process of construction equipment, instruments, meters and measuring instruments shall be kept in good condition, and the failure shall be repaired and replaced immediately after passing the verification and inspection.
3) Steel component production and construction quality process control
1) Steel parts and steel parts processing sub-project control points:
The acceptance of steel entering the site shall comply with the provisions of the relevant items mentioned above in these Rules;
After the steel line is drawn, the part number should be checked before cutting, and the material of the steel used should be fully inspected
The steel cutting surface should be free of cracks, slag inclusions, delamination, etc., and should be fully inspected
Check the heating temperature of hot processing correction and forming of parts, the correction should not exceed 900, the forming heating temperature is 900 1000, and the carbon structural steel and low-alloy steel will end the processing before the temperature drops to 700 and 800 respectively. Low-alloy steel should be naturally cooled, inspected, and all construction records should be checked.
2) Welding sub-project control points:
Check whether the welded steel is consistent with the type, grade and specification of the welding consumables used according to the welding process documents, and check the full inspection
The acceptance of welding consumables shall be in accordance with the relevant provisions of the above detailed rules;
Check the baking condition of the welding consumables and check the baking records in full;
Inspect the use of welding rod insulation cylinder;
Check that the assembly size of the joint should comply with the provisions of the process documents, and the groove and the area on both sides should be free of water, rust, oil, oxide scale, and no defects such as interlayer and cracks on the groove surface
Check the installation of the lead and extinguishing plate;
Check the appearance of the positioning weld is not allowed to have cracks, slag inclusion and other defects, and the preheating temperature should be higher than the preheating temperature of the formal weld when welding
During welding, the welding parameters are inspected, the preheating, interlayer and post-heating temperatures and holding time, the welding sequence, and the key parts are stationed
Weld internal defect inspection, weld flaw detection inspection 24 hours after the completion of welding of low-alloy steel, flaw detection report full inspection;
When the weld is repaired, the side station supervises;
11. Immediately check the construction records and the weld registration form of each welder.
3) High-strength bolt connection sub-project control points:
The friction panel surface of the high-strength bolt connection should be flat without warping, and the position and angle should meet the requirements of the drawings after the gusset plate and the component are welded
The friction surface should be free of paint, oil, scale, weld spatter, flash and burrs.
4) Steel component assembly sub-control points:
End milling plane:
Flatness: 03mm；
Perpendicularity to the axis: l 1500mm.
Allowable deviation of the installation weld bevel:
Bevel angle: 5°;
Blunt edges: 10mm。
Allowable deviation of steel member dimensions:
Column milling plane to the first mounting hole distance: 10mm；
Distance from the outermost mounting holes at both ends of the solid web beam: 30mm；
Cross-sectional geometry at the member connection: 30mm；
Web centerline offset at column and beam connections: 20mm；
The bending vector height of the compression member (member): l 1000, and should not be greater than 100mm。The distance from the center of the bolt hole of the corbel gusset plate to the center of the column meets the design requirements.
5) Steel component pre-assembly sub-project control points:
The supporting stool or platform used in pre-assembly should be measured and leveled, and all temporary fixtures should be removed during inspection
The multi-layer plate stack of high-strength bolts and ordinary bolts should be checked by a hole tester
When: D hole tester = D bolt hole -1 85% pass rate per set of holes;
D hole tester = D bolt + 1 pass rate of each group of holes = 100%;
Interface cross-section misalignment 2.
6) Steel structure anti-corrosion coating sub-control points (steel reinforced concrete steel components are not painted, rust should be removed):
The acceptance of materials shall comply with the relevant provisions of the above detailed rules;
The following environmental conditions should be suitable for painting:
Temperature 5 30
Humidity 85%.
There is no condensation on the surface before painting, and it is free of rain for 4 hours after painting
The rust removal grade of the painted surface should meet the design requirements, SA2Level 5;
The anti-corrosion coating should be uniform, without obvious wrinkles, falls, needle holes and pores, and all marks of the components should be clear after coating
The thickness of the coating should be in accordance with the design regulations (see steel structure design instructions).
2. Steel structure installation.
1) Review of engineering and technical documents:
1) Hoisting plan: It should include the preparation of hoisting, hoisting sequence, steel column hoisting, steel beam hoisting, steel frame and other contents.
2) Measurement scheme: It should include the establishment of the plane control network, the selection of reference points, the vertical transmission of the plane control network, the correction of the verticality of the steel column, the correction of the steel frame, the elevation control, and the regular measurement of the overall plane bending and overall verticality of the structure.
3) Welding process and scheme: It should include all kinds of welding process and related welding process qualification report, technical measures to ensure the quality of the weld, measures to ensure the reduction of welding deformation, the welding sequence of each joint of each frame unit column and column, column and beam and the overall welding sequence of all interfaces in order to control the overall deformation of the structure, preheating and post-heating operation instructions, etc.
4) High-strength bolt connection scheme: It should include the re-inspection scheme of high-strength bolt connection pair, the re-test scheme of anti-slip rent multi-coefficient of friction surface, the determination of construction torque, the calibration system of torque wrench, the screwing sequence of high-strength bolt pair on a single gusset plate, the screwing sequence of all nodes of the unit steel frame as a whole, the treatment of friction surface and bolt hole defects, and other technical measures to ensure the quality of high-strength bolt connection.
2) Check the technical quality management measures of the installation unit
1) Quality assurance system;
2) Construction equipment, instruments, meters and measuring instruments should be kept in good condition during the construction process, and should be repaired and replaced immediately after failure, and should be used after passing the verification and inspection.
3) Steel structure installation and construction quality process control
1) Key points of foundation handover acceptance (inspection) control:
Review the strength of the foundation concrete, which should comply with the design regulations;
The positioning axis of the building, the plane closure angle, the positioning axis and elevation of the foundation column should meet the design requirements, and the allowable deviation should meet the following provisions when the design is not required
Building positioning axis: l 20000, and 30mm
Positioning axis of the foundation column: 10mm
Base column elevation: 20mm
Anchor bolt center displacement: 20mm
The allowable deviation of the size of the anchor bolt shall comply with the following provisions:
Bolt exposed length: 0 30mm
Thread length: 0 30mm
2) Key points of quality inspection and control of incoming components:
The acceptance of the entry data should be signed by the resident supervisor:
The inspection of appearance quality mainly checks the component number, marking, deformation, surface rust, coating, friction surface, etc.;
The inspection of the external dimensions mainly focuses on the length, the size of the external connection and the welding groove to be installed.
3) Key points of quality control of steel structure hoisting measurement:
Frequent patrol for the protection of the reference point;
Permissible deviation of steel column installation:
The bottom axis of the bottom steel column is offset from the positioning axis: 30mm
Column positioning axis: 10mm
Perpendicularity of a single section column: the contract stipulates h 1000, and 60mm
The connection of the upper and lower columns is wrong: 30mm
The height difference between the top of each column of the same layer column: 50mm
Allowable deviation of steel main beam, secondary beam and compression member:
Perpendicularity: H 250, and 150mm
Sagittal height of lateral curvature: l 1000 at l 30m, and 100mm
The same height difference between the top surfaces of the two ends of the beam according to the beam: l 1000, and 100mm
The surface height difference between the main beam and the secondary beam: 2mm
The overall verticality of the main structure of the steel structure and the allowable deviation of the bending of the structural plane:
Perpendicularity: h 2500+100, and 500mm
Plane bending: l 1500, and 250mm
Allowable deviation of the total height of the main structure:
Relative elevation. The design elevation is between h 1000 and -30 30mm
Instantly check the construction records of the installation of each column of the steel structure.
4) High-strength bolt column connection sub-project control points:
Check the test of electric wrenches and torque wrenches;
Check the friction surface of the high-strength bolt joint;
Check the handling of unqualified items of high-strength bolt connection (friction surface, bolt hole dislocation), inspection and side station;
Check the screwing sequence of high-strength bolts and the initial and final screwing marks, patrol inspection and side station;
Check the final torque of the high-strength bolted joint;
Instant inspection of high-strength bolted joint construction records.
5) Welding sub-project control points:
Check whether the welded steel is consistent with the type, grade and specification of the welding consumables used according to the welding process documents, and check the full inspection
The acceptance of welding consumables shall be in accordance with the relevant provisions of the above detailed rules;
Check the baking condition of the welding consumables and check the baking records in full;
Inspect the use of welding rod insulation cylinder;
Check that the assembly size of the joint should comply with the provisions of the process documents, the groove and the area on both sides should be free of water, rust, oil, and oxide scale, and the groove surface should be free of defects such as interlayers and cracks
Check the installation of the lead and extinguishing plate;
Check the appearance of the positioning weld and do not allow cracks, slag inclusion and other defects, the preheating temperature should be higher than the preheating temperature of the formal weld during welding, inspection and side station;
During welding, inspect the welding parameters, preheating, interlayer and post-heating temperature and holding time, whether the welding sequence meets the requirements of the process documents, and stand next to the key parts
Inspection of internal defects of welds, weld flaw detection, full inspection, and full inspection of flaw detection reports 24 hours after the completion of welding of low-alloy steel;
Rework welds, repair station supervision;
11. Immediately check the construction record and the registration form of each welder's welding position (weld).
6) The key points of sub-control of the welding sub-control of the laying of profiled steel plates and studs:
The anchor support length of the medium-pressure steel plate of the composite floor slab and the main structure (beam) should meet the design requirements, and should not be less than 50mm, the end anchor connection should be reliable, and the setting position should meet the design requirements
After the bolt is welded, the bending test is checked, the bending is 30°, there should be no cracks in the weld and the heat-affected zone, the welding angle is uniform, 10% of each batch of similar components are randomly checked, and 10 pieces, among the components of the spot check, 1% of the number of welding nails is checked for each piece, but there should be 1.
7) Steel structure coating sub-project control points (steel reinforced concrete components are not painted to remove rust):
The entry of materials shall comply with the provisions of the foregoing relevant items of these Rules;
Painting should be carried out under the following environmental conditions;
Temperature 5 30
Temperature: 85%;
There is no condensation on the surface before painting, and it is free of rain for 4 hours after painting
The installation interface removes the surface dirt and repaints the anti-corrosion coating, and the thickness is according to the design requirements
Check before applying the fire retardant coating, and the anti-rust primer should meet the design requirements;
The adhesive strength and compressive strength of the fireproof coating should meet the design requirements
The bonding strength and compressive strength of the fireproof coating should meet the design requirements, and the bonding strength and compressive strength should be sampled every 500t
Check the thickness of the coating, 80% and above the area should meet the design requirements, the thinnest point should not be less than 85% of the design requirements, 10% according to the same kind of components, and 3 pieces;
Check the surface quality of the coating should not be misapplied, missing, and the coating has no defects such as delamination, hollowing, obvious depression, loose chalking and obscene slurry, and all are inspected.
5. Concealed works.
1) Steel component production part.
1. The partition plate of the box-shaped column;Studs inside box columns;
2. The part that is tightened when the components are assembled;
3. Before the coating of steel components, check the rust removal on the surface of the components.
2) Steel component installation part.
1. Check the weld surface of the top surface of the flange surface on the front beam or truss when the profiled steel plate is laid;
2. Inspection of bolt welding before the slab steel bar bundle hoop;
3. Cleaning and rust removal of burned coatings on both sides of welded joints on the construction site;
4. Fastening of steel column anchor bolts.
Sixth, the side station.
1) Steel component production part.
1. The first part of the key parts.
First and second level welds;
2. The pre-assembly process of components;
3. Re-inspection of steel and welding consumables;
4. Additional examination for welders;
5. Welding process qualification;
6. Anti-slip coefficient test of friction surface of high-strength bolt connection;
7. The weld of the repair part.
2) Steel component installation part.
1. Re-inspection of welding consumables;
2. Additional examination for welders;
3) Welding process qualification.
4. Re-inspection of high-strength bolt connection pairs;
5. Re-check the anti-slip coefficient of the friction surface of high-strength bolt connection;
6. The connection of the first batch of partial columns and high-strength bolts of the skirt beam;
7. The joints of the first batch of columns and columns, and the joints of columns and skirt beams are welded
8. Reworked welds.