Accumulated damage evaluation for a piping system by the response factor on non-stationary random process (2nd report, A two-degree-offreedom system).

Abstract

This paper shows that the average and variance of the accumulated damage caused by earth-quakes on the piping system attached to a building are related to the seismic response factor λ. The earthquakes refered to in this paper are of a non-stationary random process kind. The average is proportional to λ2 and the variance to λ4. The analytical values of the average and variance for a single-degree-of-freedom system are compared with those obtained from computer simulations. Here the model of the building is a single-degree-of-freedom system. Both average of accumulated damage are approximately equal. The variance obtained from the analysis does not coincide with that from simulations. The reason is considered to be the forced vibration by sinusoidal waves, and the sinusoidal waves included random waves. Taking account of amplitude magnification factor, the values of the variance approach those obtained from simulations.