The concept of the global resistance factors may enable non-linear and dynamic structural analysis and significantly simplify reliability verification of reinforced concrete structures. The design value of a structural resistance can be determined directly from the resistance determined from the mean or characteristic values of basic variables and appropriate global resistance factors. Presented theoretical procedures for determining the global resistance factors, are based on the principles of current European standards EN 1990 (2002) and EN 1992-1-1 (2004) and on the probabilistic theory of structural reliability. It appears that the global resistance factors depend generally on the type of concrete members and on the reinforcement ratio. General procedures are illustrated by simple examples of a beam exposed to bending and short column under compression. For the beam and target reliability index 3.8, the global resistance factor related to the characteristic value is about 1.2, the global factor related to the mean resistance is about 1.4; the approach provided in EN 1992-2 (2005), based on a reduced concrete strength and the mean of steel strength, results in the global factors decreasing with increasing reinforcement ratio from about 1.4 to 1.2. For the column, the global factors related to the mean resistance appear to attain values within the interval from 1.6 up to 1.8 depending on reinforcement ratio.
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