Supporting system with ring beam resting on tie beam is commonly adopted system as it offers more stiffness, shorter load paths , resistance against torsion and lateral loads.
Loads acting on silo
- Bin wall
- Horizontal Load (Ph) – creates Hoop Tension on the sides of wall
- Vertical Load (Pv) – acts on the cross sectional area of the bin filling and creates pressure on the bottom of silo.
- Frictional Wall load (Pw) due to the friction between material and wall which adds to the Weight of the Silo and acts on the wall.
- Cone wall
- The hopper is designed for hoop (Th) and meridional (Tl) tension forces generated due to the vertical loads
- Ring beam
- Load acting on ring beam = Pw + SW of bin wall + Pv + Load from cone
Junction of bin and cone
- The cone plate and bin plates are generally welded together with the help of stiffener plate.
- Bearing stiffeners are generally preferred when a high concentrated load (load from bin and cone) applied to either the top or bottom flange( I- section, box section generally preferred as resistance against torsion) exceeds the local yielding, crippling, or sideway buckling capacity of the web or plate (in box section).
- To protect the web or plate, from the direct compressive loads, bearing stiffeners are generally provided.
- Hence, Option 2 is generally adopted.
- The bearing stiffener is generally checked for outstand core as per Clause 8.7.1.2, buckling as per Clause 8.7.1.5, bearing strength of stiffener, torsional resistance provided as per Clause 8.7.9
JCJ 