The roof support system uses hot-dip galvanized carbon steel brackets, and the components are installed on aluminum alloy purlins using back plates or clamps. Fasteners are made of stainless steel. The support system is designed to withstand winds of 30 meters per second, ensuring long-term outdoor use.
I. Material and Performance Requirements:
1. Material requirements: The main steel structure material selected is Q235B, and the welding rod is E43 series welding rod.
2. Mechanical performance requirements: The tensile strength, elongation, yield point, cold bending test and other mechanical performance requirements of the selected steel structural materials must comply with the relevant provisions of "Carbon Structural Steel" (GB/T700-2007).
3. Chemical composition requirements: The content of chemical elements such as carbon, sulfur, and phosphorus in the main steel structure materials selected must comply with the relevant provisions of "Carbon Structural Steel" (GB/T700-2007).
II. Rust removal methods and rust removal grade requirements:
1. Steel components must undergo surface treatment. The rust removal method and rust removal grade shall comply with the relevant provisions of the current national standard "Rust Grades and Rust Removal Grades of Steel Surfaces Before Painting" (GB8923-88).
2. Rust removal methods: Steel components can be rust removed by sandblasting or shot blasting. If chemical rust removal is used, a treatment liquid with two or more functions such as rust removal, phosphating and passivation should be selected, and its quality should meet the requirements of the current national standard "General Technical Conditions for Multifunctional Steel Surface Treatment Liquid" (GB/T 12612-2005).
3. Rust removal grade: The rust removal grade should meet the Sa2 1/2 requirement.
III. Corrosion prevention requirements:
1. Steel components are protected against corrosion using a metal protective layer. All steel structure supports are hot-dip galvanized. The hot-dip galvanizing must meet the relevant requirements of "Technical Requirements and Test Methods for Hot-Dip Galvanized Coatings of Steel Components with Metallic Coatings" (GB/T13912-2002), and the thickness of the galvanized layer shall not be less than 80μm.
2. Zinc plating thickness inspection: The zinc plating thickness shall be inspected in accordance with the methods provided in "Technical Requirements and Test Methods for Hot-dip Galvanized Coatings of Steel Components".
3. Hot-dip galvanizing anti-deformation measures: Adopt a reasonable anti-deformation galvanizing scheme to prevent the components from undergoing significant deformation after hot-dip galvanizing.
Aluminum alloy material
a. Material requirements: The material is generally selected from 6061 or 6063, etc.
b. Mechanical performance requirements: The quality of the base material, chemical composition, and mechanical properties of the selected aluminum profiles must comply with the relevant provisions of GB5237.1.
c. Surface treatment must meet the technical requirements and comply with GB5237.2-2004 "Aluminum Alloy Building Profiles Part 2: Anodized and Colored Profiles".
d. The appearance quality of the profiles shall conform to the requirements of GB5237.2-2004. The surface of the profiles shall be clean and smooth, and serious defects such as cracks, peeling, corrosion and bubbles shall not be allowed.
