Calculating the reliability of single-source networks by the source head method

This paper proposes two new reliability measures that, for small networks in particular, are easy to understand and interpret and straightforward to calculate. The measures fully recognise the pressure dependency of demand and are fully capable of quantifying partial failure. The methodology is based on a recent parameter referred to as the notional net source head to fully satisfy all nodal demands. An important feature of the present formulation consists of a subtle reversal of the roles of normal and subnormal service, wherein lies the key to the proper quantification of partial failure. The final component of the methodology is a probabilistic analysis which addresses the random nature of component failures or unavailability. The final result is a sufficiently meaningful and accurate reliability measure. Damage tolerance is also characterised and quantified. The efficacy of the reliability and damage tolerance measures are highlighted using a numerical demonstration. Finally, despite the overall simplicity of the proposed approach, it is computationally efficient. (C) 1998 Elsevier Science Limited and Civil-Comp Limited. All rights reserved.