Assessment of the vulnerability of RBMK fuel channels to loads produced bythe rupturing of one channel

The possibilities for a fuel-channel pipe in RBMK, with nominal parameters, to rupture under internal and external loading caused by the rupture of a neighboring damaged channel, which becomes overheated for a general reason, are analyzed. The deformation of the masonry and the loads on the pipes ar e calculated using the R_SPACE code. The stress state of the channel tube c losest to the rupture is estimated. It is established that the maximum stre sses on the inner surface of a channel tube as the result of the ruptured c hannel are reached at the first second primarily as a result of the interna l pressure and contact forces. On the inner surface of the convex part of t he tube, the largest stresses at the eleventh second are primarily due to t he internal pressure and the maximum deflection of the column. An estimate of the stressed state according to plasicity and strength criteria shows th at when one channel ruptures at the center of the core, secondary rupture o f the pipes in the surrounding channels, which are subject to the normal op erating conditions, will not occur.