ABSTRACT
This chapter focuses on optimum design of nondeterministic structures with consideration of safety levels of a system with respect to its various failure modes, uncertainties in the dead and live loads as well as seismic forces, and random parameters in responses and resistances. Reliability is a measure of the probability of structural survival during a structure's lifetime. The derivations of reliability and probability of failure are based on a single failure mode with a single structural response and resistance case. Structures may be subjected to dead loads due to the weights of the structural and permanent fixtures; live loads due to the maximum total loads of occupancy and movable furniture; and lateral loads due to earthquakes. In a structural design, one requires the probabilities of a desired response failure are less than the allowable probabilities of failures or the safety factors for those failures greater than the allowable values.
