... structural steel: Q235, Q345, etc. High-strength low-alloy structural steel High quality carbon structural steel,special purpose steel 2 ... your requirements. 1.processing properties, Welding2.resistance to dynamic load, Fatigue3.corrosion resistance, reasonable price4.Toughness, durability, ... be out.4. Local climate: wind speed, snow load, earthquake (take any other serious weather into account)Further ...