Reducing bulk pressures and improving bulk material flow in silos: Fid-Bau Portal

Reducing bulk pressures and improving bulk material flow in silos

Kobielak, S. / Klimek, A.

Two innovative designs of silos with flexible walls allow both pressure reduction on silo walls for cohesionless, free flowing material as well as an improvement in flow for difficult flow materials. The concept of silos with prefabricated flexible walls consists of using wire sections fixed in the pilasters by means of springs which enable the pressure reduction and has the advantage in bulk solids flow. The prototype silo, which is 4 m high with a diameter of 1.5 m, consists of eight reinforced concrete prefabricates with a wall thickness of 3.5 cm, and steel pillars in which fixing strings are anchored by means of springs. Changing the spacing of the fixing strings results in different values of silo wall flexibility. The second version of a prefabricated silo with flexible walls consists of cylindrical elements with upward decreasing diameters. It contains a discharge hopper under the bottom segment and is surrounded by a supporting structure. The segments are made of vertical prefabricated elements, coupled with steel strings anchored in the pillars by means of springs. The results of calculations of flexible wall silo loads are represented in a graph, showing the obtainable pressure reduction depending on the number of working compression strings per metre of wall height. The graph implies that the value of the obtainable pressure reduction by applying flexible walls is about 20 %.