LOAD BEARING CAPACITY OF AN INTACT AND A DEGRADED PIPE SYSTEM UNDER REPEATED SIMULATED EARTHQUAKE LOADING

A series of experiments were performed at the German HDR-test-facility to assess the behaviour and the reserves in load-carrying capacity of an unflawed and a degraded pipe system when subjected to repeated simulated earthquake loading. In the case of a specially designed flexible support configuration the unflawed pipe system could be loaded up to eight times the required safe shutdown earthquake load level without any problem. The functional viability of different support configurations and support components was comprehensively tested. The load carrying capacity margins of a pipe system containing degraded components and under operating conditions were demonstrated for earthquake type loads even when these were excessive and repeatedly applied. No noticeable crack growth occurred for a single earthquake-like loading.