Application of the Ritz Averaging Method in the Analysis of the Seismic Performance of Piping Systems

Abstract

The Ritz averaging method is utilized to reduce the nonlinear characteristics of piping system supports (snubbers) to equivalent linear support stiffnesses during seismic excitation. The equivalent snubber support stiffnesses are used in seismic modal analyses of two piping systems. The analyses are performed in order to determine the effect that high snubber lockup velocities have on piping system stresses. The results show that the lockup velocity of snubbers in the systems analyzed can be safely allowed to increase above normal limits without any significant increase in nodal stresses.