(1) This part provides general principles and actions for the structural design of silos for the storage of particulate solids and tanks for the storage of fluids and shall be used in conjunction with EN 1990, other parts of EN 1991 and EN 1992 to EN 1999. (2) This part includes some provisions for actions on silo and tank structures that are not only associated with the stored solids or liquids (e.g. the effects of thermal differentials, aspects of the differential settlements of batteries of silos). (3) The following geometrical limitations apply to the design rules for silos: - the silo cross-section shapes are limited to those shown in Figure 1.1d, though minor variations may be accepted provided the structural consequences of the resulting changes in pressure are considered; - the following dimensioanl limitations apply: hb/dc < 10 hb < 100 m dc < 60 m - the transition lies in a single horizontal plane (see Figure 1.1a); - the silo does not contain an internal structure such as a cone or pyramid with its apex uppermost, cross-beams, etc. However, a rectangular silo may contain internal ties.