4.3　Raw Materials

Ⅰ　Dominant Items

4.3.1　The model，specifications，quality，quantity and performance of process structural steelwork，raw materials and standard pieces shall meet the requirements in design documents and current national standards for products.All these shall be inspected and the acceptance records shall be taken when they are delivered.

Check quantity:full check for quality certificate documents.1% random check for physical goods and at least 5 pieces are required.Re-inspect if required by the design document or relevant national standards.

Check method:check the quality certificate documents，review report and acceptance records，visual check or actual measurement.

4.3.2　The type，specifications and performance of welding materials shall meet the requirements in design documents or current national standard of JGJ 81 Technical Specifications for Welding of Steel Structure of Building.The electrode，flux，solder wire，consumable nozzle and so on shall be baked and stored according to the product instructions and welding procedure documents before use.

Check quantity:full check.

Check method:check the quality certificate documents and baking records of electrode.

4.3.3　The type，specifications and performance of high-strength bolts shall meet the requirements in design documents or current national standards.The torque coefficient of high-strength hexagon bolt shall be re-inspected before work.The pre-tension force（axial force）of torsional shear type high-strength bolt shall be re-inspected.The result shall be in accordance with relevant provisions in current national standard GB 50205 Code for Acceptance of Construction Quality of Steel Structures.

Check quantity:random check for bolts to be install，8 connecting pair in each batch.

Check method:check the quality certificate documents and re-inspection report.

4.3.4　Any one of the following steel shall be randomly re-inspected，and the re-inspection result shall meet the requirements in national current standards for products and design documents.

1　Imported steel.

2　Mixed lot of steel.

3　Steel slab with a thickness 40mm or above and performance requirement in Z-axis，or steel plate with thickness and performance requirements in design documents.

4　Steel with quality in doubt.

5　Steel with re-inspection requirements in design.

Check quantity:full check.

Check method:check the re-inspection report.

Ⅱ　General Items

4.3.5　The thickness of steel plate，specifications and allowable deviation of section steel shall meet the requirements in current national standards.

Check quantity:random check for 5 points for steel plate or section steel of each type，specification.

Check method:check with a steel ruler and vernier caliper.

4.3.6　In addition to current relevant national standards，the appearance quality of steel shall also be in accordance with the followings:

1　When there is rust，pitting or scratch on the surface of steel，its dept shall not exceed 1/2 of the negative allowable deviation for the thickness of steel.

Check quantity:full check.

Check method:observe and check with a steel rule and vernier caliper.

2　The rusting grade on surface of steel shall reach Class C or above in current national standard GB 8923 Rust Grades and Preparation Grades of Steel Surfaces before Application of Paints and Related Products；

Check quantity:full check.

Check method:check with a shovel and check with photo comparison according to current national standard GB 8923 Rust Grades and Preparation Grades of Steel Surfaces before Application of Paints and Related Products.

3　The steel shall have no defect no end or cut，e.g.crack，slag inclusion and so on.

Check quantity:full check.

Check method:visual check or check with a magnifier.