What is the test process in steel structure construction?

<> is of great significance to ensure the quality and progress of steel structure engineering. The inspection content of the steel structure production and installation unit mainly includes: enterprise qualification, production scale, number of technical personnel, professional titles and resumes, number of skilled workers and qualifications, machinery and equipment, and performance level.

The construction organization design is an important comprehensive technical document prepared by the contractor to guide the activities of the whole process of project construction, and careful review of the construction organization design is an important part of the pre-control and active control of the supervision work. Steel structure engineering should be prepared for the production stage and the installation stage respectively for the production process and installation construction organization design, the production process content should include the production stage of each process, the quality standards of each sub-item, technical requirements, as well as to ensure the quality of the product and the development of specific measures, such as the processing method of key parts, the main components of the process, technological measures, the use of processing equipment, process equipment, etc.

<> generally do steel structure raw material retest (including steel plate and profile Beijing raw material retest only do room temperature tensile and bending), bolt connection pair, anti-slip, flaw detection. Some engineering requirements are stricter, and chemical analysis of welding consumables and steel plates are also performed, and these experiments are divided into witness sampling and non-witness sampling. Steel structure engineering is a structure mainly made of steel, which is one of the main types of building structures.

Steel structure is one of the more common structural forms in modern construction engineering. China is the first country to use iron to make load-bearing structures, and has used iron to make simple load-bearing structures, while Western countries only began to use metal load-bearing structures in the 17th century. We know that the construction of steel structure engineering has to go through two stages: factory production and on-site installation, which can be completed by one construction unit, but sometimes it may also be completed by two units separately (subcontracted).

Effectively do a good job in the inspection and selection of steel structure production units and installation units.

When connecting the steel structure, the main use is to connect or weld the connectors, which mainly include anchor bolts, ordinary bolts and high-strength bolts. In the connection of connectors, the main testing standard is that the performance, specifications and varieties of connectors meet the requirements of relevant standard design regulations. The material used for the components of the steel structure mainly refers to the load-bearing material of the steel structure, according to the corresponding quality acceptance specifications, for the testing of raw materials, there should be a certificate of quality, which is in line with the requirements of the design, if there is any doubt about the quality of the steel, the steel should be sampled and inspected according to the relevant national standards.

It is necessary to further pay attention to the strict quality inspection of the steel structure building, which is of great significance for protecting people's lives and property safety, and should pay attention to the control points of the engineering quality of the steel structure in the specific testing process, so that the inspection of the engineering quality is more meticulous. Testing, certificate, tensile and bending tests related to steel raw materials; Welding process qualification test; Non-destructive testing of welds, ultrasonic, X-ray or magnetic particles, etc.; High strength bolt torque coefficient or pretension test; Detection of anti-slip coefficient of high-strength bolted connection surface; Bearing capacity test of steel grid joint; performance test of fire retardant coating for steel structure, etc. Testing of steel raw materials related items, welding process qualification test, weld nondestructive testing (ultrasonic, X-ray, magnetic particle, etc.), high-strength bolt torque coefficient or pre-tension test, high-strength bolt connection surface anti-slip coefficient test, steel grid node bearing capacity test, steel structure fireproof coating performance test, etc.

Steel structure is a structure that is mainly composed of steel materials and is one of the main types of building structures. The structure is mainly composed of steel beams, steel columns, steel trusses and other components made of section steel and steel plates, etc., and the components or components are usually connected by welds, bolts or rivets. Because of its light weight and simple construction, it is widely used in large-scale factories, venues, super high-rise buildings and other fields.

1. The quality of steel structure protective coatings should be tested according to the current national relevant product standards for coating quality;

2. The coating thickness of different types of coatings should be tested by the following methods: the thickness of the paint film can be detected by the paint film thickness gauge, and the number of sampling components should not be less than the minimum capacity of Class A test samples in the standard table, nor should it be less than 3 pieces; Each piece is measured in 5 places, and the value at each point is the average of the dry paint film thickness of 3 measurement points 50mm apart.

3. The detection of the steel grid can be divided into the bearing capacity, weld, size and deviation of the node, the unevenness of the rod and the deflection of the steel grid.

4. The wall thickness of the steel pipe members of the steel grid can be detected by ultrasonic thickness gauge, and the finishing layer should be removed before testing.

5. The irregularity of the rod axis in the steel grid can be detected by the method of pulling wire, and its irregularity shall not exceed one thousandth of the length of the rod.

1. Structure. For the detection and accounting of the slenderness ratio of steel structure members, the size of the rods can be determined according to the regulations, and the slenderness ratio of the rods should be calculated based on the actual size; The connection of the steel structure support system can be tested according to the regulations; The size of the support system components can be measured according to the regulations of the sail training; It should be verified or evaluated according to the design drawings or corresponding design specifications.

2. Painting. The quality of steel structure protective coatings should be tested in accordance with the current national relevant product standards for coating quality; The derusting grade of the steel surface can be determined by the current national standard "Rust Grade and Derusting Grade of Steel Surface Before Coating" GB8923.

3. The coating thickness of different types of coatings should be tested by the following methods:

1) The thickness of the paint film can be detected by the paint film thickness gauge, and the number of sampling components should not be less than the minimum capacity of Class A test samples in the standard table, nor should it be less than 3 pieces; Each piece is measured in 5 places, and the value at each point is the average of the dry paint film thickness of 3 measurement points 50mm apart.

2) The coating thickness of thin fireproof coatings can be detected by coating thickness tester, and the measurement method should comply with the provisions of the Technical Regulations for the Application of Fireproof Coatings for Steel Structures.

3) The thickness of the thick fireproof coating should be detected by stylus and steel ruler, and the measurement method should be in line with the provisions of the "Technical Regulations for the Application of Fireproof Coatings for Steel Structures". The thickness value and deviation value of the coating should be determined in accordance with the provisions of the Code for Acceptance of Construction Quality of Steel Structure Engineering. The appearance quality of the coating can be tested and evaluated according to the provisions of the "Code for Acceptance of Closed Oak Construction of Steel Structure Engineering Next to the Car" according to different materials.

What is the specific content of the test requirements related to the processing and production of <> steel structure, and the following Zhongda Consulting will answer for you.

1) Steel re-inspection.

When the steel belongs to one of the following conditions, it should be re-inspected before processing and cutting:

imported steel from abroad;

Mixing of different batches of steel.

Steel with doubts about quality:

The thickness of the plate is greater than or equal to 40mm, and it bears the tensile force action along the direction of the plate thickness, and the required thick plate is designed;

The safety level of the building structure is level 1, and the steel used in the main stressed components of the long-span steel structure, steel grid and steel truss structure;

The steel varieties not included in the current design specifications and the steel designed with re-inspection requirements.

2) Re-inspection of the connecting material.

1) Welding materials: The welding materials used in large, heavy and special steel structures should be sampled and inspected, and the results should meet the design requirements and the provisions of the current national standards.

3) Process tests can generally be divided into three categories:

1) Welding test.

Steel weldability test, welding process test, welding process qualification test, etc. are all weldability tests, and welding process qualification test is the most commonly encountered test in the production of various projects. Welding process qualification is the verification of welding process, is an important basic technical data to measure whether the manufacturing unit has production capacity, welding methods and technical coefficients without welding process qualification can not be used in engineering construction.

2) Anti-slip coefficient test of friction surface peib.

When the connection of the steel structure components is connected by friction type high-strength bolts, the connecting surface should be treated, and the Fan Wei shift coefficient of the connecting surface can reach the value specified in the design with the ballast spike. The technical treatment of the connecting surface is Wanyun He: stir-frying or shot peening, pickling, grinding wheel grinding, comprehensive treatment, etc.

3) Manufacturability test.

For components with complex structures, if necessary, manufacturability tests should be carried out before formal production. The manufacturability test can be a single process, or several processes or all processes; It can be individual parts, entire components, or even a single mounting unit or all mounting components.

1. Testing of steel raw materials related items, certificates, tensile and bending tests;

2. Welding process qualification test;

3. Non-destructive testing of welds, ultrasonic, X-ray or magnetic particles, etc.;

4. High-strength bolt torque coefficient or pretension test;

5. Detection of anti-slip coefficient of high-strength bolt connection surface;

6. Bearing capacity test of steel grid joint;

7. Performance test of fire retardant coating for steel structure, etc.

The retest of raw materials includes steel plates, steel rods, high-strength bolts, weld flaw detection, and the local testing center will know about the retest.

1. Testing of steel raw materials related items, certificates, tensile and bending tests;

2. Welding process qualification test;

3. Non-destructive testing of welds, ultrasonic, X-ray or magnetic particles, etc.;

4. High-strength bolt torque coefficient or pretension test;

5. Detection of anti-slip coefficient of high-strength bolt connection surface;

6. Bearing capacity test of steel grid joint;

7. Performance test of fire retardant coating for steel structure, etc.

<> generally do steel structure raw material retest (including steel plate and profile Beijing raw material retest only do room temperature tensile and bending), bolt connection pair, anti-slip, flaw detection.

Some engineering requirements are stricter, and chemical analysis of welding consumables and steel plates are also performed, and these experiments are divided into witness sampling and non-witness sampling.

The mechanical properties of steel are generally used for tensile tests and welding performance tests.

The inspection items to assess the performance of angle steel are mainly tensile test and bending test. The indicators include yield point, tensile strength, elongation and bending qualification.

Steel structure engineering generally needs to do steel structure raw material (steel plate) test, welding flaw detection test, weld no damage test, welding ball and screw rough training without bolt ball test, fireproof coating test, deflection test is about the same.

The high-strength bolt connection test should be done, and the anchor collapse bolt needs to be tested by Yanna.

1. Testing of steel raw materials related items, certificates, tensile and bending tests;

2. Welding deficit mountain connection process qualification test;

3. Nondestructive testing of welds.

Ultrasound, X-ray.

or magnetic particles, etc.; 4. High-strength bolts.

torque coefficient or pre-tension test;

5. Detection of anti-slip coefficient of high-strength bolt connection surface;

6. Bearing capacity test of steel grid joint;

7. The performance test of fire retardant coating for steel rental structure is medium.