The construction period of steel structure is short, the building span is large, the space utilization rate is high, the steel is light in weight, high in strength, toughness and plasticity, and colleagues also have the advantages of good seismic performance, convenient and diverse shapes, and high degree of factory manufacturing. Widely used in prefab steel warehouse, especially large span warehouses.Prefab warehouse is structural steel frame usually design by H steel beam, H steel column, C purlins, Z section, galvanized steel sandwich panel roof and wall.