Fuzzy safety factor

Safety factor approach for reliability of structures is established in the framework of fuzzy number theory. A simple structure is studied to describe the procedure, where geometrically and material nonlinear behaviors are taken into account. Nonlinear springs with limited ductility are considered. Two performance limits are set, material failure and instability failure. Applied axial and transverse loads are defined through fuzzy numbers. Defuzzification by center of gravity method is performed to obtain a crisp value to be compared with the required safety factor. Reinforcement to satisfy a minimum safety requirement is discussed