Analysis and Design of RCC Silo Structure Considering Indian Seismic Zone

The study concludes that single and double hopper silo configurations show different stress, moment and dynamic behaviours under self-weight, stored material pressure and seismic loading. In this study single and double hopper steel silos is analyzed under the influence of self-weight, pressure on vertical wall and seismic load. It was observed that maximum displacement along X-direction and Z-direction is reduced by 15-20% in single hopper silo. But displacement along in Y-direction i.e. along gravity direction 20 % less in double hopper silo as compare to single hopper silo. However nodal rotation are remain nearly same indicates that the torsion movement due to accidental eccentricity will be same in both cases. Natural frequency for first three modes is considerably 17% less and hence time period is more for double hopper steel silo. The numerical results further show that double hopper arrangement reduces absolute stress and X-direction shear and moment, but increases Y-direction shear and moment demand. The soil condition study confirms that soft soil is the most critical condition for silo response. The circular hopper comparison shows lower shear and moment values than the rectangular hopper, making circular geometry more favourable for seismic and stored material pressure resistance. Overall, finite element modelling in STAAD.Pro is effective for identifying critical stress zones and for improving the safety and reliability of silo structures under Indian seismic zone conditions.

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