... and neat. (2)Quick construction speed. (3)Earthquake proof. China steel structure workshopMaterialSteel frames:Q235 Q345, etc.hot roll H-style ... span, single floor, double floors!3) Base: Cement and steel foundation bolts4) Column and beam: Material Q345(S355JR)or Q235(S235JR ... ) steel, all bolts connection! Straight cross-section or Variable ...