ABSTRACT
Silos used for coal, grain and other products also need to be designed in earthquake-endangered areas. During such loadings, the silo walls experi ence additional stresses resulting from unsymmetrical pressure distributions in the silo. These pressure arrangements can lead to ovalization of the silo wall, especially for silos with a diameter to height ratio equal to or less than one. Later, the dynamic loads lead to compactions of the bulk material as well as changes of material parameters such as the angle of internal friction. In standard silo design, wall pressures from such effects are not usually taken into account. Instead, the system is reduced to a cantilever beam with several point masses being situated on top of each other to calculate appro priate additional static horizontal loads (ACI 313-77, 1983; DIN 4149, 1981; Hampe, 1991; Martens, 1988; Safarian and Harris, 1985). This procedure is in accordance with the codes of practice, where earthquake loads are covered only in a general way. Certainly one cannot be satisfied with the current situation. The following contribution deals with the bulk material-structure interaction in a silo under earthquake excitation and may in this way help to solve the problem.
