Fixed roof tanks are widely used in the petroleum and chemical industries.Engineer or tank designer who do the preliminary and detail design are normally not familiar. Their designs are basically based on the code and standard requirements and basic theory from reference book. There is limited procedure and rules in design the fixed roof, these had resulted lots of fixed roof failure in the industry It is essential for the engineers or tank designer to know how and what effects each interdiscipline's design would have on one's tank that affected the tank integrity, and taking all these consideration into his design, which shows the importance of the structural design , Structural design is the methodical investigation of the stability, strength and rigidity of structures. The basic objective in structural analysis and design is to produce a structure capable of resisting all applied loads without failure during its intended life.