ÖNORM EN 1998-4

1.1 Scope of prEN 1998-4 (1) This document is applicable to the seismic design of on-ground and elevated silos, on-ground, elevated and underground tanks, above-ground and buried pipeline systems, towers, masts and chimneys and ancillary elements attached to the aforementioned structures or in industrial facilities. (2) Unless specifically stated, EN 1998-1-1:— 2, and EN 1998-5:—4 apply. (3) prEN 1998-4 is applicable in complement to the other relevant Eurocodes. NOTE This document contains only those provisions that, in addition to the provisions of the other relevant Eurocodes, are used for the design of new structures, as listed in (1), in seismic regions. prEN 1998-4 complements in this respect the other Eurocodes. 1.2 Assumptions (1) The assumptions of EN 1998-1-1:— 2, 1.2, are assumed to be applied. (2) It is assumed that the changes in a) and b) will not take place during the construction phase or during the subsequent life span for all structures covered by prEN 1998-4, unless proper justification and verification is provided: a) substantial changes in the structural systems, supporting structures or attached ancillary elements listed in 1.1 (1); b) substantial changes of masses or mass distribution. This includes, in particular, changes in production, such as specific changes of filling loads, filling states and ancillary elements.