عنوان مقاله [English]
Reliability is the probability that a system will perform its function over a specified period of time and under specified service conditions. Reliability theory was originally developed by maritime and life insurance companies in the 19th century to compute profitable rates to charge customers. An engineering structures response depends on many uncertain factors such as loads, boundary conditions, stiffness, and mass properties. Each of these requirements is termed as a limit-state or constraint. The study of structural reliability is concerned with the calculation and prediction of the probability of limit-state violations at any stage during a structures life. The probability of the occurrence of an event such as a limit-state violation is a numerical measure of the chance of its occurring. Once the probability is determined, the next goal is to choose design alternatives that improve structural reliability and minimize the risk of failure. Some of these uncertainties can be identified and others because of unknowing problems are not considered. One of these uncertainties in structures is column base connections. engineers in designing of a structure assume that column base connections been totally pinned or fixed and by using this assumptions the structures are designed, in result of this assumptions columns or beams in structures designed conservative. In present study by considering the sensitivity of mentioned in above, the effect of rotational stiffness and the strength capacity of a base connection evaluated by considering uncertainties in this connection. Results showed that change in parameters of column base connections depends on rotational stiffness and yield moment, also by considering uncertainties and Probabilistic Relations average of rotational stiffness and rotation with specific confidence estimated.