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Steel structure truss is a kind of steel structure with large rigidity, good integrity, strong seismic ability and high structural safety. Light dead weight, save steel, small structure height, can effectively use the building space. Large adaptability, suitable for large, medium and small spans and various plane forms of buildings, convenient materials, material cross section forms, can be used to achieve large span buildings with small size material cross section, uniform material specifications, suitable for factory production, effectively improve the project progress, and can be repeatedly dismantled and reused.